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1
Chiladze, Izolda. "Factor Analysis Aspects of the Enterprise’s Operating Leverage." Applied Finance and Accounting 3, no. 1 (January 22, 2017): 75. http://dx.doi.org/10.11114/afa.v3i1.2050.
Повний текст джерелаАнотація:
The aim of the research is to selection general coefficient of operating leverage of enterprise and to great factor model of this.The subject of the research is operating risk of enterprise. Accordingly had study coefficients operating leverage, the fixed and variable costs, the conception of marginal profit and break-even points.Had mace comparative analysis of well-known coefficients of enterprise operating leverage in the article. Here are discussed relationship between coefficients of Operating Leverage, Marginal Profit, Break-even point, the production Margin of Safety and structure of costs.Generally accepted methods of analysis are used in the paper, such as analysis and synthesis, induction and deduction, quantitative and qualitative analysis methods, traditional analysis methods.Results of research had proofed that fixed costs and operating profit ratio can be recognition with General Coefficient of Operating Leverage of enterprise. Had great four-factors model of this indicator too, whose practical use will help the management of enterprises to explore positive and negative factors through the traditional analytical methods and to the adequate decisions will making.
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LASTINAWATI, ENDANG. "ANALISIS TITIK IMPAS DAN RESIKO PENDAPATAN USAHA TERNAK ITIK PETELUR DI DESA SUGIH WARAS KECAMATAN BELITANG MULYA KABUPATEN OGAN KOMERING ULU TIMUR." Jurnal Social Economic of Agriculture 5, no. 1 (May 3, 2016): 1. http://dx.doi.org/10.26418/j.sea.v5i1.15054.
Повний текст джерелаАнотація:
This study aimed to analyze the break even point and the risk of laying ducks farm income in Sugih Waras Village, Belitang Mulya Subdistrict, Ogan Komering Ulu (OKU) Timur District. The research location is determined on purposive and make all laying duck farmers using cages 15 x 5 m and 15 x 6 m or raising ± 150 laying ducks in Sugih Waras Village as the respondents of this study (census methods). The results showed that laying ducks farmers in Sugih Waras Village reach the break even point at the time of production by 740 egg per month with a price is Rp 1.111.675,13 per egg. Laying ducks farm in Sugih Waras Village likely losses indicated by the variation coefficient of 1,026 and the lower limit revenue of -1.380.102,9.Keywords : break even point, the risk of income, laying ducks
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Kotowicz, Janusz, and Sylwia Berdowska. "The influence of selected parameters on the efficiency and economic charactersistics of the oxy-type coal unit with a membrane-cryogenic oxygen separator." Archives of Thermodynamics 37, no. 1 (March 1, 2016): 73–85. http://dx.doi.org/10.1515/aoter-2016-0005.
Повний текст джерелаАнотація:
AbstractIn this paper a 600 MW oxy-type coal unit with a pulverized bed boiler and a membrane-cryogenic oxygen separator and carbon capture installation was analyzed. A membrane-cryogenic oxygen separation installation consists of a membrane module and two cryogenic distillation columns. In this system oxygen is produced with the purity equal to 95%. Installation of carbon capture was based on the physical separation method and allows to reduce the CO2emission by 90%. In this work the influence of the main parameter of the membrane process – the selectivity coefficient, on the efficiency of the coal unit was presented. The economic analysis with the use of the break-even point method was carried out. The economic calculations were realized in view of the break-even price of electricity depending on a coal unit availability.
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Kulkarni, Raghavendra G. "Insert a Root to Extract a Root of Quintic Quickly." Annales Mathematicae Silesianae 33, no. 1 (September 1, 2019): 153–58. http://dx.doi.org/10.2478/amsil-2018-0013.
Повний текст джерелаАнотація:
AbstractThe usual way of solving a solvable quintic equation has been to establish more equations than unknowns, so that some relation among the coefficients comes up, leading to the solutions. In this paper, a relation among the coefficients of a principal quintic equation is established by effecting a change of variable and inserting a root to the quintic equation, and then equating odd-powers of the resulting sextic equation to zero. This leads to an even-powered sextic equation, or equivalently a cubic equation; thus one needs to solve the cubic equation.We break from this tradition, rather factor the even-powered sextic equation in a novel fashion, such that the inserted root is identified quickly along with one root of the quintic equation in a quadratic factor of the form, u2− g2 = (u + g)(u − g). Thus there is no need to solve any cubic equation. As an extra benefit, this root is a function of only one coefficient of the given quintic equation.
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Gnenny, Oleg, Stasys Dailydka, and Vytautas Lingaitis. "DEFINITION OF LIQUIDATION PROPERTY VALUE." Business, Management and Education 11, no. 1 (June 19, 2013): 19–33. http://dx.doi.org/10.3846/bme.2013.02.
Повний текст джерелаАнотація:
The article examines the interrelation of market and liquidation value of the appraisal subject. It was established that the approach of “break-even” sale of a subject at liquidation value, which is predominating in the literature sources, shows the results essentially different from the ratio of the prices of free and accelerated sales that can be observed on the market. The article offers an alternative approach to definition of market value coefficient, which considers switching to liquidation value. This approach is based on functional dependence of the coefficient on the ratio of limited and unlimited period of exposition.
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Wang, Peng, Fei Yan Ye, Guo Rong Cao, Zheng Ling Wang, Feng Xian Qiu, and Lin Zhuang. "Preparation of New Azo Benzene Polyurethane and its Thermo-Optical Properties." Advanced Materials Research 905 (April 2014): 181–84. http://dx.doi.org/10.4028/www.scientific.net/amr.905.181.
Повний текст джерелаАнотація:
The new azo benzene polyurethane (CAPU) was synthesized by diazo coupling reaction with 1,4-Diaminobenzene, sodium nitrite, and R(-)-3-chloro-1,2-propanediol. The solubility was measured with several organic solvents. Some mechanical properties of CAPU, such as tensile strength and ratio of elongation at break, were investigated. The good thermal stability of the CAPU was shown by its absorption spectrum characterized by UV-Vis spectroscopy and its melting point of 113.5°C. Moreover, the refractive index of CAPU was obtained by the attenuated total reflection (ATR) method at different temperature and wavelength, by which the materials thermo-optic coefficient was calculated. It is shown that the material has a large thermo-optic coefficient and an obvious birefringence phenomena. And the dispersion coefficient was also calculated by the Sellmeyer equation. Because of thermo-optical properties mentioned above, the CAPU could be used to design and generate the thermo-optic switch and even all-optical switch.
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Kreckel, Holger, Annemieke Petrignani, Oldřich Novotný, Kyle Crabtree, Henrik Buhr, Benjamin J. McCall, and Andreas Wolf. "Storage ring measurements of the dissociative recombination of H 3 +." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1978 (November 13, 2012): 5088–100. http://dx.doi.org/10.1098/rsta.2012.0019.
Повний текст джерелаАнотація:
The dissociative recombination (DR) of is a key process in interstellar chemistry. More than 30 experimental studies of the DR process have been published in the literature. The DR rate coefficient results obtained from these measurements, however, have not always been consistent. The outcome seems to depend on the experimental method, on the exact measurement procedure and sometimes even on the interpretation of the experimental data. In the past two decades, heavy-ion storage rings have become the working horse for DR measurements, as they provide a direct measurement of the DR products. Furthermore, storage ring measurements yield energy-resolved rate coefficients with unprecedented resolution that allow for detailed comparison with theory. DR results from different storage ring facilities have shown a remarkable consistency throughout the years and they provide additional information on break-up dynamics and internal excitation. In this study, we will review the storage ring DR measurements that have been carried out for .
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Chao, John C. "PANEL STRUCTURAL MODELING WITH WEAK INSTRUMENTATION AND COVARIANCE RESTRICTIONS." Econometric Theory 30, no. 4 (April 23, 2014): 839–81. http://dx.doi.org/10.1017/s0266466613000492.
Повний текст джерелаАнотація:
This paper considers estimating a panel data simultaneous equations model under both coefficient and covariance matrix restrictions in a scenario where one or the other set of identifying restrictions may be invalid or may hold only weakly. We study the limiting properties of various estimators in an asymptotic framework, which takes both the cross-sectional dimensionNand the time dimensionTto infinity. In this setting as in the pure cross-sectional setup, the performance of the 2SLS estimator depends on the strength of the identifying conditions imposed on the coefficients of the model, and it fails to be consistent once these conditions break down sufficiently resulting in instruments that are too weakly correlated with the endogenous regressors. On the other hand, the between-group (BG) estimator is consistent and asymptotically normal even when coefficient restrictions fail, but it has the shortcoming that its precision depends only on variations in the cross-sectional dimension; and, hence, it is less efficient and has slower rate of convergence than alternatives, which make better use of the large time dimension. A GMM estimator, which combines the moment conditions of theBGestimator with that of the within-group IV estimator, is more robust to instrument weakness than 2SLS and is more efficient than theBGestimator, but it has a second-order bias even under strong instruments if the assumed covariance restrictions do not hold. To remedy the deficiency of the aforementioned estimators, we propose in this paper two new model averaging estimators, which are weighted averages of the GMM estimator and a bias-corrected GMM estimator. The two proposed estimators have weighting functions that depend on alternative transformations of the Bayesian Information Criterion (BIC), which is employed here to assess the validity of the covariance restrictions. We show that these new estimators have some nice robustness properties against possible failure of either the coefficient restrictions or the covariance restrictions.
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Berneckė, Vaida, Kazimieras Pukėnas, and Marius Brazaitis. "SEX DIFFERENCES IN RELIABILITY OF TESTS TO ASSESS COGNITIVE FUNCTION." Baltic Journal of Sport and Health Sciences 2, no. 101 (2016): 17–25. http://dx.doi.org/10.33607/bjshs.v2i101.51.
Повний текст джерелаАнотація:
Background. The purpose of this study was to identify whether the learning effect, fatigue, motivation, effort and/or sex-specific neural, physiological and morphological factors influenced the results of the test–retest reliability of tests to assess cognitive function. Methods. The sample included ten men (age 21.2 ± 0.4 years; body mass 79.5 ± 8.3 kg) and ten women (age 22.0 ± 1 years; body mass 60.0 ± 10.0 kg). Participants accomplished six tests (three for memory and three for attention) four times, i.e. two times (with 24 hours’ break) on successive days (teaching) and two times (with 48 hours’ break) on the third and fifth days (re-testing to assess the reliability). The reliability was assessed by calculating the average of the population, standard deviation, and intraclass correlation coefficient (ICC). Results. In males and females, measurements of attention function were highly reliable over time (ICC > .84). The ICCs for volume of spatial memory were above .79, for memory of even number recognition above .57 for both genders and for memory of figure recognition .00 for males and .79 for females. Conclusion. In young healthy males and females, measurements of attention function were highly reliable over time. Meanwhile, reliability for volume of spatial memory was good/high for both sexes, but reliability of memory for even number recognition was insufficient for both sexes and results from memory of figure recognition showed good reliability for women and insufficient reliability for men.
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Sikora, Janusz W., Łukasz Majewski, and Andrzej Puszka. "Modern Biodegradable Plastics—Processing and Properties Part II." Materials 14, no. 10 (May 12, 2021): 2523. http://dx.doi.org/10.3390/ma14102523.
Повний текст джерелаАнотація:
Four different plastics were tested: potato starch based plastic (TPS-P)–BIOPLAST GF 106/02; corn starch based plastic (TPS-C)–BioComp BF 01HP; polylactic acid (polylactide) plastic (PLA)—BioComp BF 7210 and low density polyethylene, trade name Malen E FABS 23-D022; as a petrochemical reference sample. Using the blown film extrusion method and various screw rotational speeds, films were obtained and tested, as a result of which the following were determined: breaking stress, strain at break, static and dynamic friction coefficient of film in longitudinal and transverse direction, puncture resistance and strain at break, color, brightness and gloss of film, surface roughness, barrier properties and microstructure. The biodegradable plastics tested are characterized by comparable or even better mechanical strength than petrochemical polyethylene for the range of film blowing processing parameters used here. The effect of the screw rotational speed on the mechanical characteristics of the films obtained was also demonstrated. With the increase in the screw rotational speed, the decrease of barrier properties was also observed. No correlation between roughness and permeability of gases and water vapor was shown. It was indicated that biodegradable plastics might be competitive for conventional petrochemical materials used in film blowing niche applications where cost, recyclability, optical and water vapor barrier properties are not critical.
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Fathurrohman, Yusuf Enril. "ANALISIS KELAYAKAN DAN RISIKO USAHATANI KENTANG DI DESA KUTABAWA KECAMATAN KARANGREJA KABUPATEN PURBALINGGA." Agritech: Jurnal Fakultas Pertanian Universitas Muhammadiyah Purwokerto 22, no. 2 (December 24, 2020): 127. http://dx.doi.org/10.30595/agritech.v22i2.8989.
Повний текст джерелаАнотація:
This study aims to determine the feasibility of potatoes farming in Kutabawa Village, Karangeja District, Purbalingga Regency, and farming risks such as production, price, and income. The method used in this research is the descriptive analysis method with 30 respondents who were taken through the survey method. The results showed that the feasibility study was obtained by an R / C ratio of 2.33 or> 1 which indicated that potatoes farming in Kutabawa Village, Karangreja District, Purbalingga Regency were feasible with an average income of IDR 50,633,333 and a total cost of IDR 21,744,673. In terms of production and income, it has a high risk because it has a variation coefficient of more than 0.5 (0.7945 for production and 1.00895177 for income) and also a lower limit of production of -4123 kg and a lower limit of income of - Rp.29,405. 870 where it is less than 0. Whereas seen from the price aspect it has a coefficient of variation less than 0.5 (0.206965 <0.5) and also a lower limit of production of IDR 4253.71 where the farm will always profit or break even with an increase in the price of Rp. IDR 4253.71.
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Ovanesyan, Sergey. "Alternative Method of Assessing Factors Influencing Economic System Indices." Bulletin of Baikal State University 31, no. 2 (July 9, 2021): 208–15. http://dx.doi.org/10.17150/2500-2759.2021.31(2).208-215.
Повний текст джерелаАнотація:
The article deals with developing determination methods of coefficient parameters influencing economic system indices. It is necessary to assess how economic indices respond to external and internal disturbance while making reasonable managerial decisions within economic systems. The research aims to develop a tool alternative to flexibility, as the use of the latter is not comfortable when assessing economic systems performance due to the need to present influence factors variations in percentage terms. It is based on the sensitivity theory that resides in the fact that sensitivity functions are used to assess system responses following by calculating influence coefficients related. The developed theory and method can be used in different cost management tasks and break-even operations at enterprises and allow to carry out system analysis of different situations within an economic system at a micro-level. The article illustrates the suggested tool applied to the present value, which is one of the most important issues in economic theory. It should be noted that the article searches both the influence of separate factors such as annual rate, the number of years, expected value on the present value cost and the combined influence of the mentioned above on the cost, return rate and return value.
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Hoque, M. A., and M. R. Karim. "Upscaling and Evaluation of BARI Inclined Plate Planter." Agriculturists 13, no. 2 (January 30, 2016): 1–8. http://dx.doi.org/10.3329/agric.v13i2.26582.
Повний текст джерелаАнотація:
The BARI inclined plate planter was developed for one pass tillage and seeding operation. But the planter was not capable of planting small seeds as seeds were entering between the plate and base. So, six additional MS base plates were incorporated in the planter. Three plates were redesigned and fabricated for maize seed (9 cells); for wheat, mungbean, lentil, jute, etc (32 cells) and for rice seed (11 cells). Changing of inclination of the plate is needed to use same (32 seed cell) plates for different crops and to calibrate the planter for 10% more or less seed than the predefined rates. Field test of BARI developed inclined plate planter was conducted in Gazipur, Pabna, and Barisal and its performance were evaluated. The planter was tested for sowing maize, wheat and mungbean during 2011-12. Effective field capacity and field efficiency were 0.17 ha/h and 75%, respectively. Coefficient of seed distribution uniformity and coefficient of planting depth uniformity were 97 and 94%, respectively. Time and cost saving to complete land preparation and planting of maize by inclined plate planter were 90 and 86%, respectively than conventional hand planting. The payback period of the BARI planter is 1.20 year. Break-even use time is 97 hours.The Agriculturists 2015; 13(2) 01-08
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Pimont, François, Jean-Luc Dupuy, Rodman R. Linn, and Sylvain Dupont. "Validation of FIRETEC wind-flows over a canopy and a fuel-break." International Journal of Wildland Fire 18, no. 7 (2009): 775. http://dx.doi.org/10.1071/wf07130.
Повний текст джерелаАнотація:
The wildfire model FIRETEC simulates the large coherent eddies of the wind-flows induced by the canopy. It has been qualitatively validated in its ability to simulate fire behavior, but there is still a need to validate physical submodels separately. In the present study, the dynamics and turbulence of the flow simulated by FIRETEC are validated in a manner similar to other air-flow models without fire, through comparison with measurements associated with flows within continuous and discontinuous forests captured through in situ and wind-tunnel experiments with neutral thermal stratification. The model is shown to be able to reproduce accurately all essential features of turbulent flow over both forests. Moreover, a short sensitivity study shows that the model is not very sensitive to uncertain parameters such as vegetation drag coefficient. Finally, it is shown in the discontinuous forest case that wind gusts on fuel-breaks can be very strong and significantly higher than in surrounding canopies, even if their directions are more stable. These results and others briefly reviewed in the present paper allow better understanding of wind-flow perturbations induced by fuel-breaks. This new validation added to previous ones confirms the ability of FIRETEC for investigating effects of fuel-break design on fire propagation.
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Assadi, Morteza Khalaji, Hamidreza Akhavan Armaki, and Mahmoud Zendeh Del. "Technical-Economic Analysis of Steam Double Effect Absorption Chiller-Heaters Equipped with Solar Heat Pipe System." Applied Mechanics and Materials 465-466 (December 2013): 327–34. http://dx.doi.org/10.4028/www.scientific.net/amm.465-466.327.
Повний текст джерелаАнотація:
The aim of this research is to indicate a steam double effect chiller-heater equipped with solar heat pipe in a certain space with the area of 975 m2 located in Tehran, which is currently equipped with a direct-fired single effect absorption chiller-heater. Thereafter , the most obvious differences of the two chiller-heater systems are compared: the solar cooling system increases coefficient of performance as high as 0.54, decreases CO2 dissemination by 829 tons in each year, and reduces energy consumption by 1552.42 MWh/Yr. Economic analysis of the two systems using break-even-point showed that the use of solar system is attractive in applications that have excess thermal energy, and the conversion of this energy to higher value energy markets is to be more profitable than absorption gas-fired system from 13th year on. Keywords: Technical-economic analysis, energy optimization, solar chiller, absorption chiller-heater, solar heat pipe.
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Mace, R. L., M. A. Hellberg, R. Bharuthram, and S. Baboolal. "Electron-acoustic solitons in a weakly relativistic plasma." Journal of Plasma Physics 47, no. 1 (February 1992): 61–74. http://dx.doi.org/10.1017/s0022377800024089.
Повний текст джерелаАнотація:
Weakly relativistic electron-acoustic solitons are investigated in a two-electron-component plasma whose cool electrons form a relativistic beam. A general Korteweg-de Vries (KdV) equation is derived, in the small-|ø| domain, for a plasma consisting of an arbitrary number of relativistically streaming fluid components and a hot Boltzmann component. This equation is then applied to the specific case of electron-acoustic waves. In addition, the fully nonlinear system of fluid and Poisson equations is integrated to yield electron-acoustic solitons of arbitrary amplitude. It is shown that relativistic beam effects on electron-acoustic solitons significantly increase the soliton amplitude beyond its non-relativistic value. For intermediate- to large-amplitude solitons, a finite cool-electron temperature is found to destroy the balance between nonlinearity and dispersion, yielding soliton break-up. Also, only rarefactive electronacoustic soliton solutions of our equations are found, even though the relativistic beam provides a positive contribution to the nonlinear coefficient of the KdV equation, describing relativistic, nonlinear electron-acoustic waves.
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Digdaha, Kostia, Rizal Syarief, and MH Bintoro Djoefrie. "Pengembalian Modal Usaha Program Komunitas Usaha Mikro Muamalat Berbasis Masjid Kota Bogor." MANAJEMEN IKM: Jurnal Manajemen Pengembangan Industri Kecil Menengah 11, no. 1 (August 10, 2016): 20–30. http://dx.doi.org/10.29244/mikm.11.1.20-30.
Повний текст джерелаАнотація:
In the process of eradicating poverty, Bank Muamalat with the collaboration with the Baitul Maal Muamalat (BMM), has undertaken the Mosque Based Micro Muamalat Community Program (KUM3). The problem identified in the program is that many members of KUM3 cannot make a capital return at the right time, causing them to fail in re-threading the capital. This study aims to determine the factors that affect the KUM3 member’s capital returns. Investigations carried out in four districts in Bogor City namely the Community of Loji, Pamoyanan, Pasar Anyar and Situ Gede. Eight factors that might affect the business capital was studied i.e. the value of social capital, the theory, the economy, the religion, marketing, finance, management and technical. The method used in analysing the data is the multiple logistic model . The analysis obtained a good results in the social value, theoretical value, the economy, the religion, marketing, finance, management , and technical for the KUM3 participants in Bogor City. The most influential factor in the return of capital is the social value. Two factors were studied in this value i.e. family factor and community factor. It has a tendency to break on time 6.46 times faster with the value of the regression coefficient 1.946 and value of -p 0.010 (<0.05) compared to the social disadvantage significance level of 5% . The good social value has a tendency to break even at 7,000 times compared to the less good social value. Based on the comparison between the family factor and the community factor, both have an impact on the capital returns
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Ursin, Bjørn, and Alexey Stovas. "Traveltime approximations for a layered transversely isotropic medium." GEOPHYSICS 71, no. 2 (March 2006): D23—D33. http://dx.doi.org/10.1190/1.2187716.
Повний текст джерелаАнотація:
We consider multiple transmitted, reflected, and converted qP-qSV-waves or multiple transmitted and reflected SH-waves in a horizontally layered medium that is transversely isotropic with a vertical symmetry axis (VTI). Traveltime and offset (horizontal distance) between a source and receiver, not necessarily in the same layer, are expressed as functions of horizontal slowness. These functions are given in terms of a Taylor series in slowness in exactly the same form as for a layered isotropic medium. The coefficients depend on the parameters of the anisotropic layers through which the wave has passed, and there is no weak anisotropy assumption. Using classical formulas, the traveltime or traveltime squared can then be expressed as a Taylor series in even powers of offset. These Taylor series give rise to a shifted hyperbola traveltime approximation and a new continued-fraction approximation, described by four parameters that match the Taylor series up to the sixth power in offset. Further approximations give several simplified continued-fraction approximations, all of which depend on three parameters: zero-offset traveltime, NMO velocity, and a heterogeneity coefficient. The approximations break down when there is a cusp in the group velocity for the qSV-wave. Numerical studies indicate that approximations of traveltime squared are generally better than those for traveltime. A new continued-fraction approximation that depends on three parameters is more accurate than the commonly used continued-fraction approximation and the shifted hyperbola.
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Xing, Tong, Qingfeng Song, Pengfei Qiu, Qihao Zhang, Xugui Xia, Jincheng Liao, Ruiheng Liu, et al. "Superior performance and high service stability for GeTe-based thermoelectric compounds." National Science Review 6, no. 5 (April 10, 2019): 944–54. http://dx.doi.org/10.1093/nsr/nwz052.
Повний текст джерелаАнотація:
ABSTRACT GeTe-based compounds have been intensively studied recently due to their superior thermoelectric performance, but their real applications are still limited so far due to the drastic volume variation that occurs during the rhombohedral–cubic phase transition, which may break the material or the material/electrode interface during service. Here, superior performance and high service stability for GeTe-based thermoelectric compounds are achieved by co-doping Mg and Sb into GeTe. The linear coefficient of thermal expansion before phase transition is greatly improved to match that after phase transition, yielding smooth volume variation around the phase transition temperature. Likewise, co-doping (Mg, Sb) in GeTe successfully tunes the carrier concentration to the optimal range and effectively suppresses the lattice thermal conductivity. A peak zT of 1.84 at 800 K and an average zT of 1.2 in 300–800 K have been achieved in Ge0.85Mg0.05Sb0.1Te. Finally, a Ni/Ti/Ge0.85Mg0.05Sb0.1Te thermoelectric uni-leg is fabricated and tested, showing quite good service stability even after 450 thermal cycles between 473 K and 800 K. This study will accelerate the application of GeTe-based compounds for power generation in the mid-temperature range.
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Guo, William. "The Laplace transform as an alternative general method for solving linear ordinary differential equations." STEM Education 1, no. 4 (2021): 309. http://dx.doi.org/10.3934/steme.2021020.
Повний текст джерелаАнотація:
<p style='text-indent:20px;'>The Laplace transform is a popular approach in solving ordinary differential equations (ODEs), particularly solving initial value problems (IVPs) of ODEs. Such stereotype may confuse students when they face a task of solving ODEs without explicit initial condition(s). In this paper, four case studies of solving ODEs by the Laplace transform are used to demonstrate that, firstly, how much influence of the stereotype of the Laplace transform was on student's perception of utilizing this method to solve ODEs under different initial conditions; secondly, how the generalization of the Laplace transform for solving linear ODEs with generic initial conditions can not only break down the stereotype but also broaden the applicability of the Laplace transform for solving constant-coefficient linear ODEs. These case studies also show that the Laplace transform is even more robust for obtaining the specific solutions directly from the general solution once the initial values are assigned later. This implies that the generic initial conditions in the general solution obtained by the Laplace transform could be used as a point of control for some dynamic systems.</p>
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Mohan, R., S. Raja, G. Saraswathy, and B. N. Das. "SURFACE MODIFICATION OF TPR SOLE: AN APPROACH TO IMPROVE SLIP RESISTANCE ON QUARRY AND CERAMIC TILES." Rubber Chemistry and Technology 88, no. 1 (March 1, 2015): 163–75. http://dx.doi.org/10.5254/rct.14.85965.
Повний текст джерелаАнотація:
ABSTRACT Human slip on smooth surfaces is a common accident, even though the footwear soling materials are designed with cleats and treads to provide more friction with the floor. About 20% of footwear is made with thermoplastic rubber (TPR; styrene-butadiene-styrene) soles. The slip resistance property under wet-flooring conditions of this kind of sole is poor because of the nonionic nature of the polymer. Chemical surface modification can be exploited to improve the slip-resistance property of TPR soles. The surface is chemically modified with trichloroisocyanuric acid in a methyl ethyl ketone medium (TCI/MEK; at 1, 2, and 3%) to introduce chlorinated and oxidized moieties to the rubber surface. The extent of surface modification produced in TPR with this change can be tested using attenuated total reflectance–Fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle and surface roughness measurements. The improvement in slip resistance can be evaluated by measuring the coefficient of friction using a dynamic slip-resistance tester. The extent of the change in the functional physical properties, such as surface roughness, contact angle, work adhesion, in slip resistance can be improved by optimizing the concentration of trichloroisocyanuric acid. Physicomechanical properties of unmodified and modified soles that are essential for wear performance can be tested and compared. Quantitative changes on the surface of modified rubber soles increases surface roughness, reduces contact angles, and increases work energy, so there is a considerable increase in the coefficient of friction, especially under wet floor conditions. The chemical surface treatment tends to reduce the bulk mechanical properties, such as tensile strength, elongation at break, and abrasion resistance, because cyanuric acid attacks the sole. The coefficient of friction produces a positive trend at 1 and 2% TCI/MEK treatments, but the trend is negative at a 3% concentration. The optimum surface treatment level for surface modification to enhance the slip resistance of TPR is 2% TCI/MEK.
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Di Berardino, Claudio, Giuseppe Mauro, Davide Quaglione, and Alessandro Sarra. "Structural change and the sustainability of regional convergence: Evidence from the Italian regions." Environment and Planning C: Politics and Space 35, no. 2 (July 26, 2016): 289–311. http://dx.doi.org/10.1177/0263774x16655800.
Повний текст джерелаАнотація:
Empirical studies on economic convergence have typically paid poor attention to the role played by the structural characteristics of the economy. Using OECD data for the period 1995–2007, the relationship between structural change and the convergence process of the Italian regions is analysed by integrating two approaches. A modified version of shift-and-share analysis is first used in order to break the average growth rate of labour productivity into its infra-sectoral and structural components. The existence of a relationship between the components of the growth rate and the presence of regional convergence is then assessed econometrically. Unlike in most studies reported in the literature, the regression coefficient is broken up in two separate parts to assess how much of the observed regional growth can be referred to the infra-sectoral and the structural components. The empirical results confirm the existence of a (slow) convergence, but also that only structural change has played a statistically significant support role. The regional disparities are, in most cases, unchanged or even worsened when the infra-sectoral productivity growth is considered. In terms of policy implications, strong emphasis must remain on sectoral policies: ‘place-based’ and ‘sectoral smart specialisation’ policies are crucial for the convergence process to be sustainable in the long term.
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Luna, Carlos Bruno Barreto, Edson Antonio dos Santos Filho, Danilo Diniz Siqueira, Edcleide Maria Araújo, Emanuel Pereira do Nascimento, and Tomás Jeferson Alves de Mélo. "Influence of Small Amounts of ABS and ABS-MA on PA6 Properties: Evaluation of Torque Rheometry, Mechanical, Thermomechanical, Thermal, Morphological, and Water Absorption Kinetics Characteristics." Materials 15, no. 7 (March 29, 2022): 2502. http://dx.doi.org/10.3390/ma15072502.
Повний текст джерелаАнотація:
In this work, polyamide 6 (PA6) properties were tailored and improved using a maleic anhydride-grafted acrylonitrile-butadiene-styrene terpolymer (ABS-MA). The PA6/ABS-MA blends were prepared using a co-rotational twin-screw extruder. Subsequently, the extruded pellets were injection-molded. Blends were characterized by torque rheometry, the Molau test, Fourier transform infrared spectroscopy (FTIR), impact strength, tensile strength, Heat Deflection Temperature (HDT), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Contact Angle, Scanning Electron Microscopy (SEM), and water absorption experiments. The most significant balance of properties, within the analyzed content range (5, 7.5, and 10 wt.%), was obtained for the PA6/ABS-MA (10%) blend, indicating that even low concentrations of ABS-MA can improve the properties of PA6. Significant increases in impact strength and elongation at break have been achieved compared with PA6. The elastic modulus, tensile strength, HDT, and thermal stability properties of the PA6/ABS-MA blends remained at high levels, indicating that maleic anhydride interacted with amine end-groups of PA6. Torque rheometry, the Molau test, and SEM analysis suggested interactions in the PA6/ABS-MA system, confirming the high properties obtained. Additionally, there was a decrease in water absorption and the diffusion coefficient of the PA6/ABS-MA blends, corroborating the contact angle analysis.
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DERZHO, OLEG, and ROGER GRIMSHAW. "On vorticity waves propagating in a waveguide formed by two critical layers." Journal of Fluid Mechanics 629 (June 15, 2009): 161–71. http://dx.doi.org/10.1017/s002211200900696x.
Повний текст джерелаАнотація:
A theoretical model for long vorticity waves propagating on a background shear flow is developed. The basic flow is assumed to be confined between two critical layers, respectively, located near the lower and upper rigid boundaries. In these critical layers even small disturbances will break, and eventually a thin zone of mixed fluid will appear. We derive a nonlinear evolution equation for the amplitude of a wave-like disturbance in this configuration, based on the assumption that the critical layers are replaced by thin recirculation zones attached to the lower and upper rigid boundaries, where the flow is very weak. The dispersive and time-evolution terms in this equation are typical for Korteweg–de Vries theory, but the nonlinear term is more complicated. It comprises nonlinearity associated with the shear across the waveguide, and the nonlinearity due to the flow over the recirculation zones. The coefficient of the quadratic nonlinear term may change sign, depending on the presence or otherwise of recirculation zones at the upper or lower boundary of the waveguide. We then seek steady travelling wave solutions, and show that there are no such steady solutions if the waveguide contains no density stratification. However, steady solutions including solitary waves and bores can exist if the fluid between the critical layers is weakly density stratified.
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McKenney, Daniel W., Denys Yemshanov, Glenn Fox, and Elizabeth Ramlal. "Using bioeconomic models to assess research priorities: a case study on afforestation as a carbon sequestration tool." Canadian Journal of Forest Research 36, no. 4 (April 1, 2006): 886–900. http://dx.doi.org/10.1139/x05-297.
Повний текст джерелаАнотація:
We have developed a spatial cost–benefit afforestation model that includes the tracking of five carbon pools. In this application we represent three possible afforestation strategies that could be implemented in Canada using plantations of hybrid poplar, hardwoods, and softwoods with average expected growth rates of 12–14, 5–7, and 5–7 m3· ha–1·year–1 respectively. The model provides spatially explicit insights into the cost effectiveness of afforestation as a carbon sequestration tool. Here we develop an elasticity metric and experiment to assess model sensitivity and use the results to make recommendations about research priorities. The most important biological variables across all scenarios include site suitability, which is related to refining the spatial estimates of potential yields, biomass to carbon ratios, and wood density. The most important economic variables include refinement and lowering of establishment costs and agricultural opportunity costs. Parameters that have a low impact on the break-even carbon price, suggesting refinements in knowledge in these areas would be relatively less beneficial, include decay rates for forest products, stand senescence age (the age when stand mortality reaches its maximum), bioenergy and pulpwood prices, and mean residual time for leaf litter. Less importance was also placed on the proportions of forest products in the total harvest and refining a fossil fuel substitution coefficient.
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Antypas, Imad R., and Alexey G. Dyachenko. "Modeling, Studying and Manufacturing a Cultivator Rack from Composite Materials." Mordovia University Bulletin 28, no. 3 (September 20, 2018): 366–78. http://dx.doi.org/10.15507/0236-2910.028.201803.366-378.
Повний текст джерелаАнотація:
Introduction. The composite materials have not been widely used in the Russian economy (especially in agriculture) until recently. It is relevant to use them for manufacturing some parts of agricultural machinery, for example, racks of cultivator paws. These parts often break down because of stress concentration in the places where their thickness changes during the time of plowing. The stress can be decreased by using com- posite materials. Materials and Methods. This paper presents the study results on the use of composite materials for manufacturing of cultivator racks with the appropriate selection of the volume ratio of fibers in each of the layers of fabric and layers of binder. Results. Based on the results, the design safety factor was calculated to be equal to 2. It should be noted that the values of the mechanical characteristics of the material changed because of the presence of a porosity coefficient, which was 11.6 %, while the allowable value was 4%. Field tests have shown the durability of a new composite material, even under severe operating conditions, compared to a conventional rack made of alloy steel. Conclusions. Studying the mechanical behavior of the rack geometric model and modeling a material with high mechanical properties, which later was used for manufacturing a composite material, we could get the minimum safety factor of 4, with the maximum safety factor for workers – 15. The racks from composite material are economically feasible as less expensive than used steel racks.
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Vanheukelom, Martijn, Rajarshi Das, Hervé Degée, and Bram Vandoren. "Experimental Characterization of the Initial Shear Strength of Composite Masonry including AAC Blocks and DPC Layers." Sustainability 13, no. 22 (November 18, 2021): 12749. http://dx.doi.org/10.3390/su132212749.
Повний текст джерелаАнотація:
Modern masonry structures, apart from having a load-bearing function, are more and more subjected to additional non-structural requirements related to, e.g., thermal insulation and moisture control. This has respectively led to the introduction of thermal break layers, in practice often executed using autoclaved aerated concrete (AAC) blocks, and damp proof courses (DPC) in masonry walls. These modifications have an impact on the mechanical characteristics of the masonry, such as the shear strength. In this paper, an extensive experimental campaign is therefore conducted on masonry triplets to investigate the initial shear strength of concrete block and clay brick masonry, including AAC blocks. The impact of the the presence of a polyethylene DPC layer is also studied. Moreover, the position of the DPC membrane is varied, i.e., directly on top of the brick (which is generally not recommended yet common in construction practice) and in the middle of the mortar joint. In total, 138 shear tests were performed according to the EN 1052-3 standard, with low to moderate precompression levels. The test results focus on the differences in friction angle, shear modulus, and friction coefficient. It is concluded that the presence of an AAC block decreases the initial shear strength to a value which is lower than the one assumed by Eurocode 6. Moreover, when adding a DPC membrane, the shear strength is reduced even further to almost zero, in particular when the membrane is not put in the middle of the mortar joint.
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Porozova, S. E., V. B. Kul’met’eva, T. Yu Pozdeeva, and V. O. Shokov. "Role of nanopowder agglomerates in forming the structure and properties of ceramic materials." Izvestiya vuzov. Poroshkovaya metallurgiya i funktsional’nye pokrytiya, no. 4 (December 15, 2020): 4–13. http://dx.doi.org/10.17073/1997-308x-2020-4-4-13.
Повний текст джерелаАнотація:
A comparative analysis of agglomerates obtained by spray drying and granulation methods and consolidated materials based on them was carried out. The paper provides the results obtained when studying zirconia nanopowders granulated in water medium with an agar agar additive obtained by chemical precipitation with zirconia partially stabilized by yttrium oxide (2.5 mol.%), and TZ-3Y-E powder manufactured by Tosoh Corp. (Japan) that was prepared by spray drying. Agglomerates as well as microsections and fractures of samples were studied by scanning electron, optical, atomic force microscopy, and Raman spectroscopy. The crack resistance coefficient (K1с) of samples was determined by indenting the polished surface of microsections with a Vickers pyramid. The specific surface of the powders measured by nitrogen thermal desorption during granulation remains unchanged indicating a significant open porosity of agglomerates obtained. With increasing compacting pressure under conditions of semi-dry compaction with an aqueous solution of PVA as a binder, agglomerates and even aggregates of granulated powders are destroyed, K1с increases with increasing compaction pressure and the accompanying material microstructure grinding. Powders agglomerated using spray drying break up much less intensively, K1с does not change with increasing pressure. The studies conducted allow us to agree with the authors pointing to the fractal nature of agglomerates obtained from chemically precipitated nanopowders without the use of spray drying. The use of granulated nanopowders in semi-dry compaction with the application of high pressures makes it possible to destroy not only agglomerates, but also aggregates, and to obtain nanostructured ceramics with grain sizes close to the size of initial particles.
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Kumar, Anil, Nadeem Ahmed Malik, S. Mukesh, Vijaya Rani, and Nitin Kadwasra. "Sugarcane trash chopper cum spreader-A viable machine to avoid trash burning." Journal of Applied and Natural Science 8, no. 2 (June 1, 2016): 1075–79. http://dx.doi.org/10.31018/jans.v8i2.923.
Повний текст джерелаАнотація:
Trash burning is a major problem in sugarcane to overcome this, a sugarcane trash chopper cum spreader was tested at farmer’s field for its performance and economic feasibility. The chopper cum spreader was tested at five levels of moisture content of trash (13.2, 14, 15.15, 16.6, and 18.8% db) and five levels of operationalspeed (2.6, 2.8, 2.9, 3.1, and 3.4 km/h). The performance of the sugarcane trash chopper cum spreader heavily depends on moisture content and speed of operation. The maximum field capacity (0.43ha/h) was obtained at a speed of 3.2 km/h, but maximum shredding efficiency (90.40%) was found at a speed of 2.9 km/h. Maximumuniformity coefficient (0.95) and shredding capacity (4.31 t/h) was obtained at a speed of 2.9 km/h and at a moisture content of 13.13%. Maximum trash lifting efficiency (93.95%) was observed at a speed of 2.76 km/h and at a moisture content of 13.13%. The cost of operation was Rs. 2015/ha with B: C ratio of 1.5. The break-even point ofthe chopper cum spreader was 17.7 ha and payback of the machine was 1.3 years if operated for 250 h/year. The energy consumption of machine was calculated to be 1327.7 MJ ha-1. The optimum performance of sugarcane trash chopper cum spreader was obtained at a moisture content of 13.13% (M5) and forward speed of 2.9 km h-1 (V3). The sugarcane trash chopper cum spreader may be recommended for chopping of sugarcane trash for mulching to avoid burning of trash and conserving natural resources.
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KNEISLER, Olha, and Lesia SHUPA. "OPTIMIZATION PRICING IN THE MARKET FOR VOLUNTARY HEALTH INSURANCE." WORLD OF FINANCE, no. 3(52) (2017): 7–18. http://dx.doi.org/10.35774/sf2017.03.007.
Повний текст джерелаАнотація:
Introduction. The modern market of voluntary health insurance is not able to cover a significant number of insurers. This means that insurance companies seek to attract a client among people at risk lower than the average, and, accordingly, reject the proposals for the insurance coverage of applicants with a risk level that is higher than the average. Purpose. In connection with the stated actual task the question arises the formation of scientifically-based insurance tariffs, which will ensure both the break-even activity of the insurance company, and the availability of insurance services for the largest possible population. Results. The question of the use of reasonable pricing in view of determining the correct and flexible cost of treatment and health rehabilitation, is a complex and important task for each insurer. Tariffs offered by insurers on the market should be calculated both from the actuarial and from the marketing point of view. Formation of optimal, scientifically substantiated and practically verified flexible pricing for voluntary medical insurance will improve the quality of medical care of the population, the creation of guarantees of reliable insurance protection and state interests. Conclusion. In order to optimize pricing a scientific and methodical approach to the formation of a flexible system of insurance tariffs with the use of the reliability theory of computational results modeled by Bülman-Straub is proposed. It is proved that the Bülman-Straub model, based on the determination of the confidence coefficient Z, allows us to assess the reliability of statistical information in the calculations and to determine the optimal amount of the insurance tariff for voluntary health insurance.
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Szewczak, Kamil, Helena Łoś, Rafał Pudełko, Andrzej Doroszewski, Łukasz Gluba, Mateusz Łukowski, Anna Rafalska-Przysucha, Jan Słomiński, and Bogusław Usowicz. "Agricultural Drought Monitoring by MODIS Potential Evapotranspiration Remote Sensing Data Application." Remote Sensing 12, no. 20 (October 17, 2020): 3411. http://dx.doi.org/10.3390/rs12203411.
Повний текст джерелаАнотація:
The current Polish Agricultural Drought Monitoring System (ADMS) adopted Climatic Water Balance (CWB) as the main indicator of crop losses caused by drought conditions. All meteorological data needed for CWB assessment are provided by the ground meteorological stations network. In 2018, the network consisted of 665 stations, among which in only 58 stations full weather parameters were registered. Therefore, only these stations offered a possibility to estimate the exact values of potential evapotranspiration, which is a component of the CWB algorithm. This limitation affects the quality of CWB raster maps, interpolated on the basis of the meteorological stations network for the entire country. However, the interpolation process itself may introduce errors; therefore, the adaptation of satellite data (that are spatially continuous) should be taken into account, even if the lack of data due to cloudiness remains a serious problem. In this paper, we involved the remote sensing data from MODIS instrument and considered the ability to integrate those data with values determined by using ground measurements. The paper presents results of comparisons for the CWB index assessed using ground station data and those obtained from potential evapotranspiration as the product from Moderate Resolution Imaging Spectroradiometer (MODIS) remote sensing instrument. The comparisons of results were performed for specific points (locations of ground stations) and were expressed by differences in means values. Analysis of Pearson’s correlation coefficient (r), Mann–Kendal trend test (Z-index), mean absolute error (MAE) and root mean square error (RMSE) for ten years’ series were evaluated and are presented. In addition, the basic spatial interpretation of results has been proposed. The correlation test revealed the r coefficient in the range from 0.06 to 0.68. The results show good trend agreement in time between two types of CWB with constantly higher values of this index, which is estimated using ground measurement data. In results for 34 (from 43 analyzed) stations the Mann–Kendal test provide the consistent trend, and only nine trends were inconsistent. Analyses revealed that the disagreement between the two considered indices (determined in different ways) increased significantly in the warmer period with a significant break point between R7 and R8 that falls at the end of May for each examined year. The value of MAE varied from 80 mm to 135 mm.
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Schmidt, Philip, Marita Krause, Volker Heesen, Aritra Basu, Rainer Beck, Theresa Wiegert, Judith A. Irwin, et al. "CHANG-ES." Astronomy & Astrophysics 632 (November 26, 2019): A12. http://dx.doi.org/10.1051/0004-6361/201834995.
Повний текст джерелаАнотація:
Context. Cosmic-ray electrons (CREs) originating from the star-forming discs of spiral galaxies frequently form extended radio haloes that are best observable in edge-on galaxies, where their properties can be directly investigated as a function of vertical height above the disc. Aims. For the present study, we selected two nearby edge-on galaxies from the Continuum Halos in Nearby Galaxies – an EVLA Survey (CHANG-ES), NGC 891 and 4565, which differ largely in their detectable halo extent and their star-formation rates (SFRs). Our aim is to figure out how such differences are related to the (advective and/or diffusive) CRE transport in the disc and in the halo. Methods. We use wide-band 1.5 and 6 GHz Very Large Array (VLA) observations obtained in the B, C, and D configurations, and combine the 6 GHz images with Effelsberg observations to correct for missing short spacings. After subtraction of the thermal emission, we investigate the spatially resolved synchrotron spectral index distribution in terms of CRE spectral ageing. We further compute total magnetic field strengths assuming equipartition between the cosmic-ray (CR) energy density and the magnetic field, and measure synchrotron scale heights at both frequencies. Based on the fitted vertical profiles of the synchrotron intensity and on the spectral index profile between 1.5 and 6 GHz, we create purely advective and purely diffusive CRE transport models by numerically solving the 1D diffusion–loss equation. In particular, we investigate for the first time the radial dependence of synchrotron and magnetic field scale heights, advection speeds, and diffusion coefficients, whereas previous studies of these two galaxies only determined global values of these quantities. Results. We find that the overall spectral index distribution of NGC 891 is mostly consistent with continuous CRE injection. In NGC 4565, many of the local synchrotron spectra (even in the disc) feature a break between 1.5 and 6 GHz and are thus more in line with discrete-epoch CRE injection (Jaffe–Perola (JP) or Kardashev–Pacholczyk (KP) models). This implies that CRE injection time-scales are lower than the synchrotron cooling time-scales. The synchrotron scale height of NGC 891 increases with radius, indicating that synchrotron losses are significant. NGC 891 is probably dominated by advective CRE transport at a velocity of ≳150 km s−1. In contrast, NGC 4565 is diffusion-dominated up to z = 1 kpc or higher, with a diffusion coefficient of ≥2 × 1028 cm2 s−1.
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Flanagan, Timma, Meagan Wengrove, and Bryson Robertson. "Coupled Wave Energy Converter and Nearshore Wave Propagation Models for Coastal Impact Assessments." Journal of Marine Science and Engineering 10, no. 3 (March 5, 2022): 370. http://dx.doi.org/10.3390/jmse10030370.
Повний текст джерелаАнотація:
Future nearshore wave energy converter (WEC) arrays will influence coastal wave and sediment dynamics, yet there are limited numerical methodologies to quantify their possible impacts. A novel coupled WEC-Wave numerical method was developed to quantify these possible influences on the nearshore coastal wave climate. The power performance of an Oscillating Surge Wave Energy Converter (OSWEC) array was simulated to quantify the wave energy dissipation due to the array. The OSWEC’s effect on the local wave climate was quantified by a novel coupling of two numerical models, WEC–Sim and XBeach. WEC–Sim characterizes the power extraction and wave energy transmission across the OSWEC, while XBeach captures the change in wave dynamics due to the WEC and propagates the waves to shore. This novel methodology provides the ability to directly quantify the impact of the effect of a WEC array on the local wave climate. Three case studies were analyzed to quantify the impact of a single WEC on breaking conditions and to quantify the impact of number of WECs and the array spacing on the local nearshore wave climate. Results indicate that when the WEC is placed 1100 m offshore, one WEC will cause a 1% reduction in wave height at the break point (Hsbp). As the WEC is placed further offshore, the change in Hsbp will become even smaller. Although the change in wave height from one WEC is small, WEC arrays magnify the cross–shore extent, area of influence and the magnitude of influence based on the spacing and number of WECs. For arrays with 10 or 15 WECs, the cross–shore extent was on average 200–300 m longer when the WECs were placed one to two WEC widths apart, compared with being spaced three or four widths apart. When the spacing was one WEC width apart (18 m), there was a 30% greater spatial impact on the nearshore region than arrays spaced three or four widths apart. The trend for the average transmission coefficient is within 5% for a 5, 10 or 15 WEC array, with a cumulative average of 78% transmission across all conditions.
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Wegener and Basse. "The Stability of Factor Sensitivities of German Stock Market Sector Indices: Empirical Evidence and Some Thoughts about Practical Implications." Journal of Risk and Financial Management 12, no. 3 (August 29, 2019): 140. http://dx.doi.org/10.3390/jrfm12030140.
Повний текст джерелаАнотація:
This empirical study estimates 18 single and 18 three-factor models and then tests for structural change. Break dates are identified where possible. In general, there is some empirical evidence for parameter instabilities of the estimated beta coefficients. In most cases there is no or one break point, and in some cases, there are two structural breaks examining the three factor models. The estimated factor sensitivities of single beta models seem to be even less strongly affected by structural change. Consequently, beta factors are probably more stable than some observers might believe. The break dates that have been identified generally seem to coincide with crises or recoveries after stock market slumps. This empirical finding is compatible with the point of view that bull-markets or bear-markets could matter when estimating beta coefficients. In general, the timing of structural change often seems to coincide with either the bursting of the dot-com bubble or the recovery of stock prices thereafter. The banking industry is the most notable exception. In this sector of the German economy, the global financial meltdown and the sovereign debt crisis in Europe have been of high relevance. Consequently, the internet hype of the late 1990s and the early 2000s seems to be more important for the German stock market than the US subprime debacle and the accompanying European sovereign debt crisis.
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Harianto, Eko. "Kinerja Produksi Pembesaran Ikan Lele Sangkuriang Clarias gariepinus var sangkuriang Desa Pudak Kecamatan Muaro Kumpeh Kabupaten Muara Jambi." Jurnal Akuakultur Sungai dan Danau 1, no. 1 (December 14, 2016): 32. http://dx.doi.org/10.33087/akuakultur.v1i1.10.
Повний текст джерелаАнотація:
AbstractAfrican catfish is a commodity that has prospective market and economic value. Grow out techniques are relatively simple allowing implementation of this technique on swamp land with high productivity. This study aimed to give specific information about fish productivity and its economic analysis. The study was conducted from May to August 2016 in the Pudak Village, District of Muara Kumpeh Muara Jambi. Sangkuriang fry from BPBAT Sungai Gelam with an average length of 2.3-2.7 cm and weight of 0.150-0.1725 gram were reared for 90 days using in 200×300×150 cm3 hapa nets with a density of 250 fish/m2. Fry were fed at satiation three times daily (08.00; 17.00; 21.00) with commercial pellet feed (CP 32-35%). Productivity offish reared by farmers in this swamp area show good result with survival rate, specific growth rate, feed conversion, and the coefficient of variationis 93.78%; 7.75%; 1.03; and 0.02 respectively. Average weight of fish catfish in each sampling during rearing period is 0.0150 g, 60.067 g, 101.233 and 124.567 gr. Value of R/C, breakeven point (BEP), BEP in volume is 1.46, Rp4,121,656.371 and 94.97 kg/cage respectively with production cost per kg is Rp. 10,968. Keywords: African catfish, grow out, productivity AbstrakIkan lele termasuk komoditas yang memiliki peluang pasar yang prospektif dan bernilai ekonomis tinggi. Aplikasi teknik pembesaran yang relative sederhana memungkinkan penerapan teknologi pembesaran pada lahan rawa dengan produktivitas yang tinggi. Penelitian ini bertujuan untuk Informasi spesifik kinerja produksi pembesaran ikan lele sangkuriang dan análisis ekonomi dalam usaha budidaya tersebut. Penelitian ini dilaksanakan pada bulan Mei-Agustus 2016 di Desa Pudak Kecamatan Muaro Kumpeh Kabupaten Muara Jambi Provinsi Jambi. Ikan yang digunakan dalam penelitian ini adalah benih lele Sangkuriang dengan panjang rata-rata 2,3-2,7 cm dan bobot rata-rata 0,150-0,1725 gram, berasal dari pemijahan induk BPBAT Sungai Gelam. Pemeliharaan benih lele sangkuriang menggunakan wadah hapa berukuran 200 cm x 300 cm x 150 cm. Pemeliharaan dilakukan selama 90 hari. Benih dipelihara dengan kepadatan 250 ekor/m2. Pakan yang diberikan berupa pelet komersil kadar protein pakan 32-35%, pemberian pakan dilakukan 3 kali dalam sehari yaitu pukul 08.00, pukul 17.00, dan pukul 21.00 dengan cara ad satiation (sekenyangnya). Kinerja produksi Ikan Lele Sangkuriang (Clarias gariepinus var sangkuriang) yang dipeliharan oleh pembudidaya di daerah penelitian pada daerah rawa menunjukkan hasil yang baik untuk kategori budidaya pembesaran ikan, nilai derajat kelangsungan hidup, laju pertumbuhan spesifik, konversi pakan, dan koefisien keragaman masing-masing sebesar 93,78% ; 7,75%; 1,03; dan 0.02. Pada akhir pemeliharaan bobot rata-rata ikan lele sangkuriang selama empat kali periode sampling masing masing sebesar 0,0150 gr, 60,067 gr, 101,233 gr dan 124,567 gr. Nilai R/C sebesar 1,46, Break even point (BEP) pada usaha pembesaran ikan lele sangkuriang di Desa Pudak ini sebesar Rp 4.121.656,371, BEP berdasarkan volum penjualan dalam bentuk ekor diperoleh nilai BEP sebesar 94.97 kg/karamba, Harga pokok penjualan yaitu Rp 10,968/kg.Kata kunci : Ikan lele sangkuriang, Kinerja produksi, Pembesaran ikan, Pertumbuhan
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Lu, Kunquan, Zexian Cao, Meiying Hou, Zehui Jiang, Rong Shen, Qiang Wang, Gang Sun, and Jixing Liu. "The mechanism of earthquake." International Journal of Modern Physics B 32, no. 07 (March 5, 2018): 1850080. http://dx.doi.org/10.1142/s0217979218500807.
Повний текст джерелаАнотація:
The physical mechanism of earthquake remains a challenging issue to be clarified. Seismologists used to attribute shallow earthquake to the elastic rebound of crustal rocks. The seismic energy calculated following the elastic rebound theory and with the data of experimental results upon rocks, however, shows a large discrepancy with measurement — a fact that has been dubbed as “the heat flow paradox”. For the intermediate-focus and deep-focus earthquakes, both occurring in the region of the mantle, there is not reasonable explanation either. This paper will discuss the physical mechanism of earthquake from a new perspective, starting from the fact that both the crust and the mantle are discrete collective system of matters with slow dynamics, as well as from the basic principles of physics, especially some new concepts of condensed matter physics emerged in the recent years. (1) Stress distribution in earth’s crust: Without taking the tectonic force into account, according to the rheological principle of “everything flows”, the normal stress and transverse stress must be balanced due to the effect of gravitational pressure over a long period of time, thus no differential stress in the original crustal rocks is to be expected. The tectonic force is successively transferred and accumulated via stick-slip motions of rock blocks to squeeze the fault gouge and then exerted upon other rock blocks. The superposition of such additional lateral tectonic force and the original stress gives rise to the real-time stress in crustal rocks. The mechanical characteristics of fault gouge are different from rocks as it consists of granular matters. The elastic moduli of the fault gouges are much less than those of rocks, and they become larger with increasing pressure. This peculiarity of the fault gouge leads to a tectonic force increasing with depth in a nonlinear fashion. The distribution and variation of the tectonic stress in the crust are specified. (2) The strength of crust rocks: The gravitational pressure can initiate the elasticity–plasticity transition in crust rocks. By calculating the depth dependence of elasticity–plasticity transition and according to the actual situation analysis, the behaviors of crust rocks can be categorized in three typical zones: elastic, partially plastic and fully plastic. As the proportion of plastic portion reaches about 10% in the partially plastic zone, plastic interconnection may occur and the variation of shear strength in rocks is mainly characterized by plastic behavior. The equivalent coefficient of friction for the plastic slip is smaller by an order of magnitude, or even less than that for brittle fracture, thus the shear strength of rocks by plastic sliding is much less than that by brittle breaking. Moreover, with increasing depth a number of other factors can further reduce the shear yield strength of rocks. On the other hand, since earthquake is a large-scale damage, the rock breaking must occur along the weakest path. Therefore, the actual fracture strength of rocks in a shallow earthquake is assuredly lower than the average shear strength of rocks as generally observed. The typical distributions of the average strength and actual fracture strength in crustal rocks varying with depth are schematically illustrated. (3) The conditions for earthquake occurrence and mechanisms of earthquake: An earthquake will lead to volume expansion, and volume expansion must break through the obstacle. The condition for an earthquake to occur is as follows: the tectonic force exceeds the sum of the fracture strength of rock, the friction force of fault boundary and the resistance from obstacles. Therefore, the shallow earthquake is characterized by plastic sliding of rocks that break through the obstacles. Accordingly, four possible patterns for shallow earthquakes are put forward. Deep-focus earthquakes are believed to result from a wide-range rock flow that breaks the jam. Both shallow earthquakes and deep-focus earthquakes are the energy release caused by the slip or flow of rocks following a jamming–unjamming transition. (4) The energetics and impending precursors of earthquake: The energy of earthquake is the kinetic energy released from the jamming–unjamming transition. Calculation shows that the kinetic energy of seismic rock sliding is comparable with the total work demanded for rocks’ shear failure and overcoming of frictional resistance. There will be no heat flow paradox. Meanwhile, some valuable seismic precursors are likely to be identified by observing the accumulation of additional tectonic forces, local geological changes, as well as the effect of rock state changes, etc.
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Ghodoosipour, Stolle, Nistor, Mohammadian, and Goseberg. "Experimental Study on Extreme Hydrodynamic Loading on Pipelines Part 2: Induced Force Analysis." Journal of Marine Science and Engineering 7, no. 8 (August 9, 2019): 262. http://dx.doi.org/10.3390/jmse7080262.
Повний текст джерелаАнотація:
Adequate design of pipelines used for oil, gas, water, and wastewater transmission is essential not only for their proper operation but particularly to avoid failure and the possible extreme consequences. This is even more drastic in nearshore environments, where pipelines are potentially exposed to extreme hydrodynamic events, such as tsunami- or storm-surge-induced inundation. The American Society of Civil Engineers (ASCE), in its ASCE7 Chapter 6 on Tsunami Loads and Effects which is the new standard for tsunami impacts and loading, specifically stresses the need to study loads on pipelines located in tsunami-prone areas. To address this issue, this study is the first of its kind to investigate loading on pipelines due to tsunami-like bores. A comprehensive program of physical model experiments was conducted in the Dam-Break Hydraulic Flume at the University of Ottawa, Canada. The tests simulated on-land tsunami flow inundation propagating over a coastal plain. This allowed to record and investigate the hydrodynamic forces exerted on the pipe due to the tsunami-like, dam-break waves. Different pipe configurations, as well as various flow conditions, were tested to investigate their influence on exerted forces and moments. The goal of this study was to propose, based on the results of this study, resistance and lift coefficients which could be used for the design of pipelines located in tsunami-prone areas. The values of the resistance and lift coefficients investigated were found to be in the range of 1 < CR<3.5 and 0.5 ≤ CL<3, respectively. To that end, the study provides an upper envelope of resistance and lift coefficients over a wide range of Froude numbers for design purposes.
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Agiotis, Leonidas, and Michel Meunier. "Nonlinear thermal lensing of high repetition rate ultrafast laser light in plasmonic nano-colloids." Nanophotonics 11, no. 5 (January 18, 2022): 1051–62. http://dx.doi.org/10.1515/nanoph-2021-0775.
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Abstract We report on experimental observations of phenomenological self-trapping in plasmonic colloids of varying plasmon peaks in the visible/near infrared. A femtosecond (fs) oscillator is used in both pulsed (35 fs, 76 MHz) and continuous wave (cw) operation for comparison. We show that for both modes and for all examined colloids (and under typically applied external focusing conditions in self-trapping studies in colloidal media) nonlinear propagation is governed by thermal defocusing of the focused beam, which precedes the steady-state regime reached by particle diffusion, even far from the plasmon resonance (or equivalently for non-plasmonic colloids, even for low absorption coefficients). A strategy for the utilization of high repetition fs pulses to mitigate thermal lensing and promote gradient force-induced self-trapping is discussed. Notably, nonlinear thermal lensing is further accompanied by natural convection due to the horizontal configuration of the setup. Under resonant illumination, for both fs and cw cases, we observe mode break-up of the beam profile, most likely due to azimuthal modulation instability. Importantly, time-resolved observations of the break-up indicate that in the fs case, thermal convection heat transfer is reduced in magnitude and significantly decoupled in time from thermal conduction, presumably due to temperature increase confinement near the particles. We anticipate that our findings will trigger interest toward the use of high repetition fs pulses for self-channeling applications in nano-colloids.
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Demetrescu, Matei, and Uwe Hassler. "(WHEN) DO LONG AUTOREGRESSIONS ACCOUNT FOR NEGLECTED CHANGES IN PARAMETERS?" Econometric Theory 32, no. 6 (July 13, 2015): 1317–48. http://dx.doi.org/10.1017/s0266466615000225.
Повний текст джерелаАнотація:
To construct forecasts for time series exhibiting breaks, the paper examines long autoregressions, where the number of lags is growing with T, and possible breaks are simply ignored. The paper shows that the OLS estimators are still elementwise consistent for the true autoregressive coefficients when neglecting a break in mean, but the sum of the estimators converges to unity. Thanks to this unit-root like behavior of the fitted model, the resulting conditional forecasts are consistent for the true values. As long as the dynamic structure is invariant, the robustness property of the forecasts holds a) under data-dependent lag length selection, b) for a piecewise smoothly varying mean function, and c) under general autoregressive dynamics of possibly infinite order including stationary long memory. Under breaks in the dynamic structure, however, estimators are asymptotically biased, and the forecasts from long autoregressions are biased themselves even in the limit.
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Nakamura, Yusuke, Yoshiyuki Kuno, Daiki Kanazawa, Kosuke Iwasaki, Tomomi Takeshima, and Kenta Takashima. "PP014 Will A Proposed Policy In Japan, Health Gold License, Work?" International Journal of Technology Assessment in Health Care 33, S1 (2017): 74. http://dx.doi.org/10.1017/s0266462317002069.
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INTRODUCTION:Mr. Shinjiro Koizumi and some younger members of Japan's National Diet suggested a new policy, “Health Gold License” which would introduce financial incentives to encourage population health management, with people receiving medical checkups receiving a reduction in coinsurance from the current 30 percent to 20 percent. In this research, to evaluate the policy, we adjusted confounding factors of those insured who receive medical checkups (Medical-Checkup Group) and those who do not (Non-Medical-Checkup Group) using claims data, and estimated the effect of medical checkups on medical costs.METHODS:We analyzed Japanese employee-based claims data provided by the Japan Medical Data Center Co. Ltd. for the 3 million insured from January 2005 to December 2015. Two regression models were developed. Under model A, explanatory variables were year, age, dummy variables for various hierarchical condition categories and for medical checkups. Under model B, explanatory variables were estimated medical costs per patient per month (PMPM) in 2012 and a dummy variable for medical checkups. We also simulated the financial impact if Japan introduced Health Gold License for all insured.RESULTS:The coefficients of medical checkups in model A and in model B were -JPY4,816 PMPM and -JPY8,735 PMPM, respectively. The gap of medical costs between the Medical-Checkup Group and Non-Medical-Checkup Group was JPY4,588 PMPM, without any adjustment. If all of those insured received medical checkups, the breakeven coinsurance would be 27.2 percent.CONCLUSIONS:The Medical-Checkup Group is less expensive than Non-Medical-Checkup Group by at least 30%, therefore, the break-even coinsurance for them would be 0 percent. However, because most of those insured have already gone to medical check-ups every year, if the coinsurance were reduced from 30 percent to 20 percent for all insured, the finance would be largely negative. The break-even as 27.2 percent, we believe, would not incentivize the Non-Medical-Checkup Group to receive medical checkups. Therefore, the coinsurance reduction proposed under Health Gold License is not fully justified financially.
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Lee, Sangeun, Toshio Okazumi, Youngjoo Kwak, and Kuniyoshi Takeuchi. "Vulnerability proxy selection and risk calculation formula for global flood risk assessment: a preliminary study." Water Policy 17, no. 1 (June 30, 2014): 8–25. http://dx.doi.org/10.2166/wp.2014.158.
Повний текст джерелаАнотація:
By using the data from 15 countries in Asia, this study aims to improve the current global flood risk assessment methods in the aspects of vulnerability proxy selection and a risk calculation formula. In estimating global flood risk, the current methods treat vulnerability in a very simplistic manner. Based on recent literature and empirical findings, this study classifies vulnerability into susceptibility (in terms of marginalized groups, unplanned urbanization, and weak governance), and coping capacity. Each of the four components is, in light of global data availability, expressed by eight proxies, namely, age-related dependency ratio, undernourishment prevalence, urbanization growth rate, deforestation, corruption perceptions index, and three core scores from the Hyogo Framework for Action. Regarding the risk calculation formula, this study tries to break through the limitations of the multiple regression, which is commonly used for estimating coefficients and parameters, by applying the partial least squares regression (PLSR) method. The PLSR method makes it possible to include many proxies in the formula without lowering the explanatory power, even when the proxies are highly correlated.
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Jochmans, Koen, and Vincenzo Verardi. "A portmanteau test for serial correlation in a linear panel model." Stata Journal: Promoting communications on statistics and Stata 20, no. 1 (March 2020): 149–61. http://dx.doi.org/10.1177/1536867x20909695.
Повний текст джерелаАнотація:
We introduce the command xtserialpm to perform the portmanteau test developed in Jochmans (2019, Cambridge Working Papers in Economics No. 1993, University of Cambridge, Faculty of Economics). The procedure tests for serial correlation of arbitrary form in the errors of a linear panel model after estimation of the regression coefficients by the within-group estimator. The test is designed for short panels and can deal with general missing-data patterns. The test is different from the related portmanteau test of Inoue and Solon (2006, Econometric Theory 22: 835–851), which is performed by xtistest (Wursten, 2018, Stata Journal 18: 76–100), in that it allows for heteroskedasticity. In simulations documented below, xtserialpm is found to provide a more powerful test than xthrtest (Wursten 2018), which performs the test for first-order autocorrelation of Born and Breitung (2016, Econometric Reviews 35: 1290–1316). We also provide comparisons with xtistest and xtserial (Drukker, 2003, Stata Journal 3: 168–177). These tests perform well under stationarity but break down under even mild forms of heteroskedasticity.
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Rascón-Solano, Joel, Jesús M. Olivas-García, Oscar A. Aguirre-Calderón, Javier Hernández-Salas, Marcos Portillo-Vázquez, Samuel A. García-García, and Viridiana S. Galván-Moreno. "Industrial investment project: An alternative for community development in the forest of Basihuare ejido, Chihuahua, Mexico." Revista Chapingo Serie Ciencias Forestales y del Ambiente 28, no. 2 (April 30, 2022): 169–87. http://dx.doi.org/10.5154/r.rchscfa.2020.12.070.
Повний текст джерелаАнотація:
Introduction: To strengthen production chains in the state of Chihuahua, it is necessary to evaluate the feasibility of establishing sawmills in forest communities and ejidos. Objective: To formulate a sawmill investment project for the Basihuare ejido, Guachochi, Chihuahua, and to evaluate its viability by estimating financial and economic indicators. Materials and methods: Projections of supply from 2020 to 2024 were made based on the records of roundwood inputs of the Pinus genus from 2015 to 2019. Sawmilling coefficients, sawn timber grade distribution and market price were determined with historical information from a private industry located in Guachochi. Feasibility was evaluated by estimating the income tax established according to income. Results and discussion: A net present value of 16 194 605 MXN at a discount rate of 12 %, an internal rate of return of 78.69 % and a benefit/cost relationship of 1.25 were estimated. A break-even point of 1 520 255 bf produced, a payback period of 2.07 years and an economic profitability of 61.14 % were also determined. Conclusion: The indicators were positive in all cases, which shows that the project is financially viable. The methodology used for the formulation and evaluation of investment projects in the forestry sector can be replicated and adapted by different agrarian nuclei
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Lee, Jungeun Olivia, L. John Horwood, Woo Jung Lee, Daniel A. Hackman, Geraldine Fh McLeod, and Joseph M. Boden. "Social Causation, Social Selection, or Common Determinants? Examining Competing Explanations for the Link Between Young Adult Unemployment and Nicotine Dependence." Nicotine & Tobacco Research 22, no. 11 (August 13, 2019): 2006–13. http://dx.doi.org/10.1093/ntr/ntz131.
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Abstract Introduction Unemployment has been related to smoking, yet the causal nature of the association is subject to continued debate. Social causation argues that unemployment triggers changes in smoking, whereas the social selection hypothesis proposes that pre-existing smoking behavior lowers the probability of maintaining employment. The present study tested these competing explanations while accounting for another alternative explanation—common liability. Methods Data were from the Christchurch Health and Development Study, a longitudinal cohort followed from birth to age 35. Odds were generated for having nicotine dependence in models for social causation and being unemployed in models for social selection. These models were extended to include possible common liability factors during childhood (eg, novelty seeking) and young adulthood (eg, major depression). Results In the model testing social causation, coefficients representing the impacts of unemployment on nicotine dependence remained statistically significant and robust (odds ratio [OR] = 1.55; 95% confidence interval [CI] = 1.20, 2.00), even after accounting for common determinant measures. In contrast, a reverse social selection model revealed that coefficients representing the impacts of nicotine dependence on unemployment substantially attenuated and became statistically nonsignificant as childhood factors were added (OR = 1.14; 95% CI = 0.90, 1.45). Conclusions Unemployment may serve as inroads to nicotine addiction among young adults, not the other way, even in the context of nicotine dependence, a more impaired form of smoking that may arguably hold higher potential to generate social selection processes. This social causation process cannot be completely attributable to common determinant factors. Implications It is critical to clarify whether unemployment triggers changes in smoking behaviors (ie, social causation) or vice versa (ie, social selection)—the answers to the question will lead to public health strategies with very different intervention targets to break the linkage. The current study findings favor social causation over social selection, regardless of gender, and support a needed shift in service profiles for unemployed young adults—from a narrow focus on job skills training to a more holistic approach that incorporates knowledge from addiction science in which unemployed young adults can find needed services to cope with job loss.
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Zinchenko, Alexander Z., and Robert H. Davis. "General rheology of highly concentrated emulsions with insoluble surfactant." Journal of Fluid Mechanics 816 (March 8, 2017): 661–704. http://dx.doi.org/10.1017/jfm.2017.91.
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A general constitutive model is constructed and validated for highly concentrated monodisperse emulsions of deformable drops with insoluble surfactant through long-time, large-scale and high-resolution multidrop simulations. There is the same amount of surfactant on each drop, and the linear model is assumed for the surface tension versus the surfactant concentration. The surfactant surface transport is coupled to multidrop hydrodynamics through the convective–diffusive equation and the interfacial stress balance. Only the limit of small surfactant diffusivities is addressed, when this parameter does not affect the rheology. An Oldroyd constitutive equation is postulated, with five variable coefficients depending on one instantaneous flow invariant (chosen as the drop-phase contribution to the dissipation rate). These coefficients are found by fitting the model to five precise rheological functions from two steady base flows at arbitrary deformation rates. One base flow is planar extension (PE) ($\dot{\unicode[STIX]{x1D6E4}}x_{1},-\dot{\unicode[STIX]{x1D6E4}}x_{2},0$), the other one is planar mixed flow (PM) ($\dot{\unicode[STIX]{x1D6FE}}x_{2}$, $\dot{\unicode[STIX]{x1D6FE}}\unicode[STIX]{x1D712}x_{1}$, 0) with $\unicode[STIX]{x1D712}=0.16$. A small but finite $\unicode[STIX]{x1D712}$ (a precise choice in the range $\unicode[STIX]{x1D712}\sim 0.1$ is unimportant) provides a necessarily perturbation to exclude severe ergodic difficulties and abnormal, kinked behaviour inherent in simple shear for high drop volume fractions $c$, especially at small capillary numbers $Ca$ and small drop-to-medium viscosity ratios $\unicode[STIX]{x1D706}$. The database rheological functions are obtained for $c=0.45{-}0.6$, $\unicode[STIX]{x1D706}=0.25{-}3$ and surfactant elasticities $\unicode[STIX]{x1D6FD}=0.05{-}0.2$ (based on the equilibrium surfactant concentration) from long-time simulations by a multipole-accelerated boundary-integral code with $N=100{-}200$ drops in a periodic cell and 2000–4000 boundary elements per drop. The code is an extension from Zinchenko & Davis (J. Fluid Mech., vol. 779, 2015, pp. 197–244) to account for surfactant transport and Marangoni stresses. Massive drop cusping or (sometimes) drop break-up limit the range of $Ca$ from above in the base flows, but there is no substantial lower limitation owing to the absence of phase transition difficulties. At small $\unicode[STIX]{x1D706}$, even minimal surface contamination may have a strong effect on the rheology. The simulations remain accurate for quite strong drop interactions, when the PE emulsion viscosity is nine times that for the carrier fluid. The model validation against a steady PM flow with a different $\unicode[STIX]{x1D712}=0.5$ shows a very good agreement for various $Ca$, $c$ and $\unicode[STIX]{x1D706}$. In the three PE and PM time-dependent flow tests, the quasi-steady approximation is found to predict stresses poorly. In contrast, the combination of the steady-state results for PE and PM used in the present method to generate the Oldroyd parameters gives a model with much better predictions for these time-dependent flows.
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Oliynyk, Oleksandr, Olena Skoromna, Oleksandr Gorokh, Vitaliya Mishchenko, and Maryna Yevdokimova. "New approach to risk assessment of certain agricultural products." Agricultural and Resource Economics: International Scientific E-Journal, March 20, 2021, 44–57. http://dx.doi.org/10.51599/are.2021.07.01.03.
Повний текст джерелаАнотація:
Purpose. The main purpose of the research is to substantiate a new approach to assessing the risk of production and sales of certain types of the agricultural products.
Methodology / approach. The abstract-and-logical method (systematization of publications on risk assessment of the risk level); the economic and statistical one (determination of root-mean-square deviation (δ), the coefficient of variation (v), and the coefficient of residual variation); the marginal analysis (determination of the break-even level of production of certain types of the products) have been used.
Results. The methodological approach that allows determining the risk level of certain types of the products has been developed and it has been proposed to determine not only with the help of the break-even point, but also to supplement the following indicators – determining the reserve of safety and the reserve of financial strength. It is proved that similar obtained assessments of the certain product type production risk level using the analysis of variation indices can be reached by examining the break-even point indices, financial safety margin and the margin of safety. Research results show that unlike variation indices, the break-even point index, the financial safety margin index and the margin of safety index show the maximum amount of possible net income reduction.
Originality / scientific novelty. The methodical approach to the assessment of the risk level of agricultural production at the given level of profitability, which is based on the comparison of the levels of production intensity of certain types of the products, that ensures their break-even point, has been substantiated.
Practical value. The application of the proposed methodological approach allows the managers to determine how much to reduce the amount of the net income or the level of production intensity, but not to fall into the zone of loss.
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Yoon, Sungho, Eric Curtis, John Denton, and John Longley. "The Effect of Clearance on Shrouded and Unshrouded Turbines at Two Levels of Reaction." Journal of Turbomachinery 136, no. 2 (September 26, 2013). http://dx.doi.org/10.1115/1.4023942.
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In this paper, the effect of seal clearance on the efficiency of a turbine with a shrouded rotor is compared with the effect of the tip clearance when the same turbine has an unshrouded rotor. The shrouded versus unshrouded comparison was undertaken for two turbine stage designs one having 50% reaction, the other having 24% reaction. Measurements for a range of clearances, including very small clearances, showed three important phenomena. Firstly, as the clearance is reduced, there is a “break-even clearance” at which both the shrouded turbine and the unshrouded turbine have the same efficiency. If the clearance is reduced further, the unshrouded turbine performs better than the shrouded turbine, with the difference at zero clearance termed the “offset loss.” This is contrary to the traditional assumption that both shrouded and unshrouded turbines have the same efficiency at zero clearance. The physics of the break-even clearance and the offset loss are discussed. Secondly, the use of a lower reaction had the effect of reducing the tip leakage efficiency penalty for both the shrouded and the unshrouded turbines. In order to understand the effect of reaction on the tip leakage, an analytical model was used and it was found that the tip leakage efficiency penalty should be understood as the dissipated kinetic energy rather than either the tip leakage mass flow rate or the tip leakage loss coefficient. Thirdly, it was also observed that, at a fixed flow coefficient, the fractional change in the output power with clearance was approximately twice the fractional change in efficiency with clearance. This was explained by using an analytical model.
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Berneckė, Vaida, Nerijus Eimantas, Henrikas Paulauskas, Beata Skaisgirytė, Justas Kudrevičius, and Marius Brazaitis. "Assessment of The Reliability of Cognitive (Attention and Memory) Tests." Baltic Journal of Sport and Health Sciences 3, no. 86 (October 19, 2018). http://dx.doi.org/10.33607/bjshs.v3i86.263.
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Research background and hypothesis. Special neuropsychological tests, which are used to assess cognitive functions in clinical practice, are often complicated, time-consuming, demanding special knowledge and expensive; therefore, cognitive functions frequently remain insufficiently assessed. For this reason, our selected and validated tests intended for the assessment of short-term memory and attention could be successfully applied in sports and clinical rehabilitation. Research aim. The aim of this study was to assess the reliability of the tests of cognitive functions (memory and attention). Research methods. The reliability of the tests was assessed using the intraclass correlation coefficient (ICC) and variation coefficient (VC). Young and healthy students (n = 41), aged from 18 to 30 (24.6 ± 2.3), participated in the research. The participants accomplished the tests 4 times, i. e. 2 times (with a one-hour break) on the first day (teaching) and 2 times (with a one-hour break) on the second day (reliability testing). Research results. The results of testing the volume of spatial memory and even number recognition ranged from high to very high reliability of the tests. The results of ICC single of testing memory for figure recognition demonstrated low reliability, whereas ICC average proved average reliability. The results of complex reaction assessment, search for image samples and attention transfer ranged from high to a very high reliability of the tests. Discussion and conclusions. The reliability of the tests of memory and attention assessment is high (with the exception of figure recognition tests, the reliability of which is average/low); therefore, the tests are suitable to be used in sport and clinical rehabilitation practice, aiming at determining the changes in cognitive functions under the influence of external factors, e. g. cold, heat, etc.Keywords: brain functions, validity, stability, testing.
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Glatz-Reichenbach, Joachim, and Ralf Strümpler. "The influence of filler properties on the strong PTC effect of resistivity in polymer based conducting composites." MRS Proceedings 699 (2001). http://dx.doi.org/10.1557/proc-699-r9.3.
Повний текст джерелаАнотація:
AbstractPolymer based composites are very attractive materials for a plurality of technical applications. For electrical purposes the resistivity of such materials can be tuned over many orders of magnitude from highly insulating (1014&cm) to well conducting (10-3&cm) states. One particular class of polymer based composites even show a strong non-linear reversible change in resistivity with temperature between conduction and insulation. Such a pronounced effect of positive temperature coefficient of resistivity (PTCR) can be technically used, for example, in self regulating heating devices, for temperature sensing or, as a very challenging and important task, for current (i.e. over- as well as short-circuit currents) limiting and interrupting devices. The PTCR-devices act similar like fuses but repetitively, which offers technical and economical benefits.In the present work we investigate how the physical properties of the conducting filler influence the switching characteristics of the PTC material. Experimental results on resistivity and its change under active heating by Joule's losses during current flow are presented and discussed for different composites, compounded with fillers like carbon black, Ni/Ag, TiB2 or WC/Co. The strong resistance change caused by break-off and separation of particle-particle micro-contacts is driven by the very different thermal expansion coefficients of filler and matrix. It is in particular demonstrated how the heat capacity of filler-particles influences the dynamics of the micro-contact separation.
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Naufal, Ismah, Atikah Nurhayati, Achmad Rizal, Ine Maulina, and Asep Agus Handaka Suryana. "Feasibility Analysis of Seaweed, Gracilaria sp., Cultivation in Polyculture System In Ponds: A Case Study From Domas Village, Pontang Serang Banten, Indonesia." Asian Journal of Fisheries and Aquatic Research, January 5, 2022, 1–11. http://dx.doi.org/10.9734/ajfar/2022/v16i130361.
Повний текст джерелаАнотація:
This research aims to analyze business feasibility of cultivation of seaweed, Gracilaria sp., and factors that affect farmers' income in Domas Village, Pontang District, Serang Banten Regency. This research was conducted from April 2021 to June 2021 in Domas Village, Pontang Subdistrict, Serang Regency, Banten and was conducted by survey method. Location determination was done by the census sampling method. Sampling was conducted for 35 seaweed farmers in Domas Village. The data analysis used was a business feasibility analysis that includes income analysis, R/C ratio, Payback period, Break event point, sensitivity analysis, and multiple linear regression analysis. The result of the business feasibility analysis obtained was the profit value of Gracilaria sp., cultivation in Domas Village, which was 115,168,232 / year, R / C of 1.32% means that the business was worth running, the payback period value was 1.51 years since the company was established. The product's BEP (kg) value in this study was 1,320 kg. Meaning that the break-even point will be reached if the cultivation produces Gracilaria sp. So that the business can be developed. As for the sensitivity, the value increases acceptable operating costs by 5%. In addition, the calculation of sensitivity to the decline in selling value is known to be a very sensitive variable because it’s 3% decrease will lower the of R / C value to less than 1. This indicates that variable selling prices are more sensitive to investment value than operating costs. Factors that affect the income of cultivators in Domas Village of Pontang Subdistrict are Modal (X1), Total Production (X2), Gracilaria sp. (X5), and Bandeng Fish Seedlings (X6) with a coefficient of determination of 91.8%.