Journal articles on the topic 'Lag order selection'
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Butler, Ronald, and Marc Paolella. "Autoregressive Lag—Order Selection Using Conditional Saddlepoint Approximations." Econometrics 5, no. 3 (September 19, 2017): 43. http://dx.doi.org/10.3390/econometrics5030043.
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Morales, Marco. "Lag order selection for an optimal autoregressive covariance matrix estimator." Journal of Applied Statistics 37, no. 5 (March 23, 2010): 739–48. http://dx.doi.org/10.1080/02664760902873969.
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Kapetanios, George. "Incorporating lag order selection uncertainty in parameter inference for AR models." Economics Letters 72, no. 2 (August 2001): 137–44. http://dx.doi.org/10.1016/s0165-1765(01)00433-5.
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Jia, Guijin, Youqing Wang, and Biao Huang. "Dynamic higher-order cumulants analysis for state monitoring based on a novel lag selection." Information Sciences 331 (February 2016): 45–66. http://dx.doi.org/10.1016/j.ins.2015.10.029.
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Cavaliere, Giuseppe, Luca De Angelis, Anders Rahbek, and A. M. Robert Taylor. "DETERMINING THE COINTEGRATION RANK IN HETEROSKEDASTIC VAR MODELS OF UNKNOWN ORDER." Econometric Theory 34, no. 2 (September 20, 2016): 349–82. http://dx.doi.org/10.1017/s0266466616000335.
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We investigate the asymptotic and finite sample properties of a number of methods for estimating the cointegration rank in integrated vector autoregressive systems of unknown autoregressive order driven by heteroskedastic shocks. We allow for both conditional and unconditional heteroskedasticity of a very general form. We establish the conditions required on the penalty functions such that standard information criterion-based methods, such as the Bayesian information criterion [BIC], when employed either sequentially or jointly, can be used to consistently estimate both the cointegration rank and the autoregressive lag order. In doing so we also correct errors which appear in the proofs provided for the consistency of information-based estimators in the homoskedastic case by Aznar and Salvador (2002, Econometric Theory 18, 926–947). We also extend the corpus of available large sample theory for the conventional sequential approach of Johansen (1995, Likelihood-Based Inference in Cointegrated Vector Autoregressive Models. Oxford University Press) and the associated wild bootstrap implementation thereof of Cavaliere, Rahbek, and Taylor (2014, Econometric Reviews 33, 606–650) to the case where the lag order is unknown. In particular, we show that these methods remain valid under heteroskedasticity and an unknown lag length provided the lag length is first chosen by a consistent method, again such as the BIC. The relative finite sample properties of the different methods discussed are investigated in a Monte Carlo simulation study. The two best performing methods in this study are a wild bootstrap implementation of the Johansen (1995, Likelihood-Based Inference in Cointegrated Vector Autoregressive Models. Oxford University Press) procedure implemented with BIC selection of the lag length and joint IC approach (cf. Phillips, 1996, Econometrica 64, 763–812) which uses the BIC to jointly select the lag order and the cointegration rank.
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Takeyasu, Kazuhiro. "Brand Selection and Its Matrix Structure―Expansion of its Block Matrix to the Third Order Lag―." Business and Management Research 5, no. 4 (November 25, 2016): 31. http://dx.doi.org/10.5430/bmr.v5n4p31.
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Focusing that consumers’ are apt to buy superior brand when they are accustomed or bored to use current brand, new analysis method is introduced. Before buying data and after buying data is stated using liner model. When above stated events occur, transition matrix becomes upper triangular matrix. In this paper, equation using transition matrix stated by the Block Matrix is expanded to the third order lag and the method is newly re-built. These are confirmed by numerical examples. S-step forecasting model is also introduced. This approach makes it possible to identify brand position in the market and it can be utilized for building useful and effective marketing plan.
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Liao, Zhipeng, and Peter C. B. Phillips. "AUTOMATED ESTIMATION OF VECTOR ERROR CORRECTION MODELS." Econometric Theory 31, no. 3 (March 13, 2015): 581–646. http://dx.doi.org/10.1017/s026646661500002x.
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Model selection and associated issues of post-model selection inference present well known challenges in empirical econometric research. These modeling issues are manifest in all applied work but they are particularly acute in multivariate time series settings such as cointegrated systems where multiple interconnected decisions can materially affect the form of the model and its interpretation. In cointegrated system modeling, empirical estimation typically proceeds in a stepwise manner that involves the determination of cointegrating rank and autoregressive lag order in a reduced rank vector autoregression followed by estimation and inference. This paper proposes an automated approach to cointegrated system modeling that uses adaptive shrinkage techniques to estimate vector error correction models with unknown cointegrating rank structure and unknown transient lag dynamic order. These methods enable simultaneous order estimation of the cointegrating rank and autoregressive order in conjunction with oracle-like efficient estimation of the cointegrating matrix and transient dynamics. As such they offer considerable advantages to the practitioner as an automated approach to the estimation of cointegrated systems. The paper develops the new methods, derives their limit theory, discusses implementation, reports simulations, and presents an empirical illustration with macroeconomic aggregates.
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Zhang, Bingkai, Benzhong Dai, Li Zhang, Jiali Liu, and Zhen Cao. "The Correlated Multi-color Optical Variations of BL Lac Object S5 0716+714." Publications of the Astronomical Society of Australia 27, no. 3 (2010): 296–301. http://dx.doi.org/10.1071/as09086.
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AbstractS5 0716+714 is a well-studied BL Lac object in the sky. Verifying the existence of correlations among the flux variations in different bands serves as an important tool to investigate the emission processes. To examine the possible existence of a lag between variations in different optical bands on this source, we employ a discrete correlation function analysis on the light curves. In order to obtain statistically meaningful values for the cross-correlation time lags and their related uncertainties, we perform Monte Carlo simulations called ‘flux redistribution/random subset selection’. Our analysis confirms that the variations in different optical light curves are strongly correlated. The time lags show a hint of the variations in high frequency band leading those in low frequency band of the order of a few minutes.
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Pinho, João Pedro, Bruno Mezêncio, Desidério Cano Porras, Julio Cerca Serrão, and Alberto Carlos Amadio. "Relationship Between Knee Extensors Power Output and Vastus Lateralis EMG Activation in Elderly Women: Influence of Mother Wavelet Selection." Open Sports Sciences Journal 10, no. 1 (December 29, 2017): 263–71. http://dx.doi.org/10.2174/1875399x01710010263.
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Purpose:The main objective of this study was to compare frequency parameters produced by six mother wavelets pinpointing the most feasible to investigate electromyographic (EMG) parameters while producing knee extension power in elderly women. The influence of different load conditions in mother wavelet selection and power output were also analyzed.Methods:Thirteen sedentary elderly women (69.3 ± 4.1 years) took part in the study. Participants executed 6 repetitions of 3 load condition (30%, 50% and 70% of the maximal) with the concentric phase of the knee extension movement as quickly as possible. Kinematic data obtained by video analysis, an anthropometric model and Newtonian mechanics were used to calculate knee extensors’ power. A continuous wavelet analysis was used as a time-frequency transformation strategy of vastus lateralis and biceps femoris EMG data and six different mother wavelets were selected: Morlet; 4th, 8th and 44th order Daubechie, 4th order Coiflet and 5th order Symlet.Results:44th order Daubechie showed the highest maximal cross correlation value and no differences were seen between different mother wavelets and cross correlation at zero lag and in the lag variable. Although increased knee extensors peak power at higher loads were seen, no differences in vastus lateralis or biceps femoris root mean square values were obtained.Conclusion:44th order Daubechie mother wavelet was pinpointed as the most suitable to obtain EMG time-frequency parameters. We have also seen that different load conditions do not seem to have an influence on mother wavelet selection.
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Papoulias, Fotis A. "On the Nonlinear Dynamics of Pursuit Guidance for Marine Vehicles." Journal of Ship Research 37, no. 04 (December 1, 1993): 342–53. http://dx.doi.org/10.5957/jsr.1993.37.4.342.
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A theoretical analysis of the nonlinear dynamic phenomena involved in pure pursuit guidance of marine vehicles is performed. Nomoto's model (Crane et al 1989) is used to provide the basis for the main vehicle turning lag. Results obtained in closed-form expressions demonstrate the existence of bifurcations to periodic solutions. The center manifold of the system is evaluated to within a third-order approximation. Third-and fifth-order expansions are utilized in order to provide information on limit cycle existence and stability. Recommendations regarding the appropriate selection of control design parameters are provided.
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Jin, Shanhai, Ryo Kikuuwe, and Motoji Yamamoto. "Parameter Selection Guidelines for a Parabolic Sliding Mode Filter Based on Frequency and Time Domain Characteristics." Journal of Control Science and Engineering 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/923679.
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This paper presents the results of quantitative performance evaluation of an authors’ new parabolic sliding mode filter, which is for removing noise from signals in robotics and mechatronics applications, based on the frequency and time domain characteristics. Based on the evaluation results, the paper presents selection guidelines of two parameters of the filter. The evaluation results show that, in the frequency domain, the noise removing capability of the filter is almost the same as that of the second-order Butterworth low-pass filter (2-LPF), but its phase lag is smaller (maximum 150 degree) than that of 2-LPF (maximum 180 degree). Moreover, the filter produces smaller phase lag than a conventional parabolic sliding mode filter with appropriate selection of the parameters. In the time domain, the filter produces smaller overshoot than 2-LPF and the conventional one, while maintaining short transient time, by using an appropriately selected parameter. The presented parameter selection guidelines state that the values of the parameters should be chosen according to some estimated characteristics of the input and some desired characteristics of the output. The effectiveness of the filter and the presented guidelines is validated through numerical examples and their application to a closed-loop, force control of a robot manipulator.
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Xaba, Diteboho, Ntebogang Dinah Moroke, Johnson Arkaah, and Charlemagne Pooe. "A Comparative Study Of Stock Price Forecasting Using Nonlinear Models." Risk Governance and Control: Financial Markets and Institutions 7, no. 2 (2017): 7–17. http://dx.doi.org/10.22495/rgcv7i2art1.
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This study compared the in-sample forecasting accuracy of three forecasting nonlinear models namely: the Smooth Transition Regression (STR) model, the Threshold Autoregressive (TAR) model and the Markov-switching Autoregressive (MS-AR) model. Nonlinearity tests were used to confirm the validity of the assumptions of the study. The study used model selection criteria, SBC to select the optimal lag order and for the selection of appropriate models. The Mean Square Error (MSE), Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) served as the error measures in evaluating the forecasting ability of the models. The MS-AR models proved to perform well with lower error measures as compared to LSTR and TAR models in most cases.
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Wen, Yan, Ziliang Zou, Hongshun Li, Zhonghuai Xiang, and Ningjia He. "Analysis of codon usage patterns inMorus notabilisbased on genome and transcriptome data." Genome 60, no. 6 (June 2017): 473–84. http://dx.doi.org/10.1139/gen-2016-0129.
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Codons play important roles in regulating gene expression levels and mRNA half-lives. However, codon usage and related studies in multicellular organisms still lag far behind those in unicellular organisms. In this study, we describe for the first time genome-wide patterns of codon bias in Morus notabilis (mulberry tree), and analyze genome-wide codon usage in 12 other species within the order Rosales. The codon usage of M. notabilis was affected by nucleotide composition, mutation pressure, nature selection, and gene expression level. Translational selection optimal codons were identified and highly expressed genes of M. notabilis tended to use the optimal codons. Genes with higher expression levels have shorter coding region and lower amino acid complexity. Housekeeping genes showed stronger translational selection, which, notably, was not caused by the large differences between the expression level of housekeeping genes and other genes.
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Silva, Fabrício Drummond, Alcione Miranda dos Santos, Rita da Graça Carvalhal Frazão Corrêa, and Arlene de Jesus Mendes Caldas. "Temporal relationship between rainfall, temperature and occurrence of dengue cases in São Luís, Maranhão, Brazil." Ciência & Saúde Coletiva 21, no. 2 (February 2016): 641–46. http://dx.doi.org/10.1590/1413-81232015212.09592015.
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Abstract This study analyzed the relationship between rainfall, temperature and occurrence of dengue cases. Ecological study performed with autochthonous dengue cases reported during 2003 to 2010 in São Luís, Maranhão. Data of rainfall and temperature were collected monthly. The monthly incidence of dengue cases was calculated by year/100,000 inhabitants. In order to identify the influence of climate variables and dengue cases different distributed lag models using negative binomial distribution were considered. Model selection was based on the lowest AIC (Akaike Information Criterion). Thirteen thousand, four hundred forty-four cases of dengue between 2003 and 2010 were reported, with peaks in 2005, 2007 and 2010. The correlation between rainfall and the occurrence of dengue cases showed increase in the first months after the rainy months. Occurrence of dengue cases was observed during all the period of study. Only rainfall-lag per three months showed a positive association with the number of cases dengue. Thus, this municipality is considered as an endemic and epidemic site. In addition, the relation between rainfall and dengue cases was significant with a lag of three months. These results should be useful to the future development of politics healthy for dengue prevention and control.
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Herwartz, Helmut, Simone Maxand, Fabian H. C. Raters, and Yabibal M. Walle. "Panel Unit-root Tests for Heteroskedastic Panels." Stata Journal: Promoting communications on statistics and Stata 18, no. 1 (March 2018): 184–96. http://dx.doi.org/10.1177/1536867x1801800111.
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In this article, we describe the command xtpurt, which implements the heteroskedasticity-robust panel unit-root tests suggested in Herwartz and Siedenburg (2008, Computational Statistics and Data Analysis 53: 137–150), Demetrescu and Hanck (2012a, Economics Letters 117: 10–13), and, recently, Herwartz, Maxand, and Walle (2017, Center for European, Governance and Economic Development Research Discussion Papers 314). While the former two tests are robust to time-varying volatility when the data contain only an intercept, the latter test is unique because it is asymptotically pivotal for trending heteroskedastic panels. Moreover, xtpurt incorporates lag-order selection, prewhitening, and detrending procedures to account for serial correlation and trending data.
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Hill, Jonathan B., and Kaiji Motegi. "A MAX-CORRELATION WHITE NOISE TEST FOR WEAKLY DEPENDENT TIME SERIES." Econometric Theory 36, no. 5 (May 12, 2020): 907–60. http://dx.doi.org/10.1017/s0266466619000367.
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This article presents a bootstrapped p-value white noise test based on the maximum correlation, for a time series that may be weakly dependent under the null hypothesis. The time series may be prefiltered residuals. The test statistic is a normalized weighted maximum sample correlation coefficient $ \max _{1\leq h\leq \mathcal {L}_{n}}\sqrt {n}|\hat {\omega }_{n}(h)\hat {\rho }_{n}(h)|$, where $\hat {\omega }_{n}(h)$ are weights and the maximum lag $ \mathcal {L}_{n}$ increases at a rate slower than the sample size n. We only require uncorrelatedness under the null hypothesis, along with a moment contraction dependence property that includes mixing and nonmixing sequences. We show Shao’s (2011, Annals of Statistics 35, 1773–1801) dependent wild bootstrap is valid for a much larger class of processes than originally considered. It is also valid for residuals from a general class of parametric models as long as the bootstrap is applied to a first-order expansion of the sample correlation. We prove the bootstrap is asymptotically valid without exploiting extreme value theory (standard in the literature) or recent Gaussian approximation theory. Finally, we extend Escanciano and Lobato’s (2009, Journal of Econometrics 151, 140–149) automatic maximum lag selection to our setting with an unbounded lag set that ensures a consistent white noise test, and find it works extremely well in controlled experiments.
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Aisien, Leonard Nosa. "The Impact of Exchange Rate on Foreign Private Investment in Nigeria." Asian Finance & Banking Review 2, no. 2 (November 17, 2018): 19–32. http://dx.doi.org/10.46281/asfbr.v2i2.208.
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The study examined the impact of exchange rate on foreign private investment using quarterly time series date from Nigeria for the period 2007 to 2017. Foreign private investment in the study was disaggregated into foreign direct investment and foreign portfolio investment in order to ascertain their separate reactions to changes in the exchange rate of the naira against the US dollars. The empirical analysis was based on the VAR estimation procedure using three lagged periods adopted on the basis of various lag order selection criteria. The empirical result revealed that devaluation/depreciation of the naira adversely affects foreign direct investment and foreign portfolio investment in Nigeria. Increased in the size of the domestic market and development of the financial sector were found to stimulate foreign private investment while high inflation rate in the domestic economy discourages foreign private investment in Nigeria. The study, therefore, recommended among others that the Central Bank of Nigeria should continue to initiate more proactive policy intervention policies to stabilize the exchange rate of the naira in order to stimulate more foreign private investment in Nigeria.
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Piao, Chang Hao, Yu Sheng Li, Hong Tao Qiao, and Cong Teng. "The Study of Digital DC-DC Converter of Electric Vehicles." Applied Mechanics and Materials 224 (November 2012): 466–69. http://dx.doi.org/10.4028/www.scientific.net/amm.224.466.
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This paper presents a two-stage DC-DC converter for electric vehicles that controlled by using a digital MCU with a lag algorithm. Because the fuel vehicle causes many environmental issues, the electric vehicle becomes a new tendency in vehicle fields. The voltage of power battery is very high and can’t charge for lead-acid battery directly, so DC-DC converter is an essential device. In order to absorb the advantage of digital converter and meet the requirement of widely range input voltage, a digital DC-DC converters for electric vehicle is proposed. The BUCK and half bridge topology was analysis in detail and chosen for the DC-DC converter. A digital DC-DC converter system which includes the hardware and software was designed. The sample circuit, driven circuit and how to make the power transformer is described in detail in hardware design. The software mainly consist the voltage regulate program and CAN communication program. A lag compensator was designed for the voltage regulate. A prototype was made and test in the charge of the lead-acid battery. The result shows the correctness of the topology selection and circuit design. It proved that the DC-DC converter can charge the lead-acid battery within working voltage of power battery and meet the specification basically.
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Maszczyk, Adam, Robert Roczniok, Przemysław Pietraszewski, Arkadiusz Stanula, Adam Zając, and Artur Gołaś. "Time Series Approach To Athletes Motor Potential." Polish Journal of Sport and Tourism 19, no. 2 (November 1, 2012): 103–6. http://dx.doi.org/10.2478/v10197-012-0010-5.
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AbstractIntroduction. The aim of this study was to determine the dynamics of changes in selected motor abilities of javelin throwers and to determine predictors of javelin throw distances. Material and methods. Research material included the results obtained from a group of 60 competitors from the Silesia Region of Poland, aged 14 - 15 years. In order to answer the research question, the following statistical analysis were employed: Pearson's linear correlation coefficients, vectors R0 and R1, time series analysis, distributed lag analysis and Almon distributed lag analysis and coefficient of concordance φ2Results. The correlation analyzes allowed for a selection of two variables for further analyses: specific strength of arms and trunk (SSAT) and specific strength of shoulders girdle and trunk (SSGT). Calculated indexes revealed that the level of SSAT showed a constant upward tendency (+15%). The highest rise in SSAT level was recorded in the 4th and 5th quarter (+9%). The level of SSGT showed an upward tendency nearly (+6%). In this case, the highest rise was observed in the 7th and 8th quarter (+4.5%). Conclusions. The standardized regression analysis revealed that the variable of specific power of arms and trunk (SOBT) is the most important predictor for javelin throw distance with a full approach run.
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Klepáč, Václav, and David Hampel. "Prediction of Bankruptcy with SVM Classifiers Among Retail Business Companies in EU." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 64, no. 2 (2016): 627–34. http://dx.doi.org/10.11118/actaun201664020627.
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Article focuses on the prediction of bankruptcy of the 850 medium-sized retail business companies in EU from which 48 companies gone bankrupt in 2014 with respect to lag of the used features. From various types of classification models we chose Support vector machines method with linear, polynomial and radial kernels to acquire best results. Pre-processing is enhanced with filter based feature selection like Gain ratio, Chi-square and Relief algorithm to acquire attributes with the best information value. On this basis we deal with random samples of financial data to measure prediction accuracy with the confusion matrices and area under curve values for different kernel types and selected features. From the results it is obvious that with the rising distance to the bankruptcy there drops precision of bankruptcy prediction. The last year (2013) with avaible financial data offers best total prediction accuracy, thus we also infer both the Error I and II types for better recognizance. The 3rd order polynomial kernel offers better accuracy for bankruptcy prediction than linear and radial versions. But in terms of the total accuracy we recommend to use radial kernel without feature selection.
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Quero, David, Pierre Vuillemin, and Charles Poussot-Vassal. "A Generalized State-Space Aeroservoelastic Model Based on Tangential Interpolation." Aerospace 6, no. 1 (January 15, 2019): 9. http://dx.doi.org/10.3390/aerospace6010009.
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In this work, a new approach for the generation of a generalized state-space aeroservoelastic model based on tangential interpolation is presented. The resulting system of differential algebraic equations (DAE) is reduced to a set of ordinary differential equations (ODE) by residualization of the non-proper part of the transfer function matrix. The generalized state-space is of minimal order and allows for the application of the force summation method (FSM) for the aircraft loads recovery. Compared to the classical rational function approximation (RFA) approach, the presented method provides a minimal order realization with exact interpolation of the unsteady aerodynamic forces in tangential directions, avoiding any selection of poles (lag states). The new approach is applied first for the generation of an aerodynamic model for the bidimensional unsteady incompressible flow in the time domain. Next, an application on the generation of an aeroservoelastic model for loads evaluation of the flutter reduced order assessment (FERMAT) model under atmospheric disturbances is done, showing an excellent agreement with the reference model in the frequency domain. The proposed aeroservoelastic model of minimal order is suited for loads analysis and multivariable control design, and an application to a gust loads alleviation (GLA) strategy is shown.
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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.
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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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Dobrzański, Przemysław, and Witold Oleksiak. "Design and Analysis Methods for Composite Bonded Joints." Transactions on Aerospace Research 2021, no. 1 (March 1, 2021): 45–63. http://dx.doi.org/10.2478/tar-2021-0004.
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Abstract A literature review on existing design and analysis methods for composite adhesively bonded joints has been conducted. Methods that might form a basis for development of practical engineering methodology for adhesively bonded joints were selected and described. Starting from the simplest and the fastest analytical methods (closed-form solutions): average shear stress, shear lag model and adhesive beam model through more complex and more time consuming numerical methods supported by finite element analysis: global models, local models, cohesive zone models. Assumptions and applicability of each method was discussed. Simple and fast methods in order to be reliable have to include many conservative assumptions and therefore may lead to over-designed structure (weight penalty). Structural optimization and weight reduction require the usage of more complex and time consuming methods. Therefore, selection of adequate methods should always be balanced against strength, durability, costs and weight.
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Rahmati, Omid, Zahra Kalantari, Mahmood Samadi, Evelyn Uuemaai, Davoud Davoudi Moghaddam, Omid Asadi Nalivan, Georgia Destouni, and Dieu Tien Bui. "GIS-Based Site Selection for Check Dams in Watersheds: Considering Geomorphometric and Topo-Hydrological Factors." Sustainability 11, no. 20 (October 13, 2019): 5639. http://dx.doi.org/10.3390/su11205639.
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Check dams are widely used watershed management measures for reducing flood peak discharge and sediment transport, and increasing lag time and groundwater recharge throughout the world. However, identifying the best suitable sites for check dams within the stream networks of various watersheds remains challenging. This study aimed to develop an open-source software with user-friendly interface for screening the stream network possibilities and identifying and guiding the selection of suitable sites for check dams within watersheds. In this developed site selection software (SSS), multi-criteria decision analysis (MCDA) was integrated into geographic information systems (GIS), which allowed for numerous spatial data of the multiple criteria to be relatively simply and visually processed. Different geomorphometric and topo-hydrological factors were considered and accounted for to enhance the SSS identification of the best locations for check dams. The factors included topographic wetness index (TWI), terrain ruggedness index (TRI), topographic position index (TPI), sediment transport index (STI), stream power index (SPI), slope, drainage density (DD), and stream order (SO). The site identification performance of the SSS was assessed using the receiver operating characteristic (ROC) curve method, with results for the case study example of the Poldokhtar watershed in Iran showing excellent performance and identifying 327 potential sites for efficient check dam construction in this watershed. The SSS tool is not site-specific but is rather general, adaptive, and comprehensive, such that it can and should be further applied and tested across different watersheds and parts of the world.
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Takeyasu, Kazuhiro. "Analysis of the Preference Shift of Customer Brand Selection and its Matrix Structure : Expansion of its Block Matrix to the Third Order Lag and Compression of the Variables." Industrial Engineering & Management Systems 17, no. 3 (September 30, 2018): 434–43. http://dx.doi.org/10.7232/iems.2018.17.3.434.
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Pont, Adam R., Anna R. Charron, Roselyn M. Wilson, and Rhonda M. Brand. "Effects of active sunscreen ingredient combinations on the topical penetration of the herbicide 2,4-dichlorophenoxyacetic acid." Toxicology and Industrial Health 19, no. 1 (February 2003): 1–8. http://dx.doi.org/10.1191/0748233703th172oa.
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Sunscreen use can reduce the incidence of certain skin cancers. However, a number of commercially available formulations have been shown to enhance the transdermal penetration of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). Most of the active ingredients used in these compounds can individually act as penetration enhancers. Commercial sunscreens frequently contain multiple active ingredients in order to provide broad sunscreen protection. The purpose of this study was therefore to examine the effect of these active ingredient combinations on the transdermal absorption of 2,4-D in vitro. All six of the combinations tested resulted in increased cumulative penetration ( P <0.01) and faster lag times ( P <0.05). The 2,4-D cumulative penetration in the presence of the OFF! Deepwoods combination was significantly greater than the absorption with either the individual ingredients or their average ( P <0.05). A systematic study designed to isolate the chemicals responsible for this enhancement demonstrated that with UV absorbers DEET synergistically increased the 2,4-D penetration and that DEET’s cumulative enhancement properties correlate with its concentration. By contrast, octocrylene significantly slowed the lag time when used in combinations and was the only active ingredient that showed any antagonistic effects on 2,4-D penetration. Because none of the active ingredient combinations were able to inhibit dermal uptake of 2,4-D, it seems that proper selection of inert ingredients may be the most feasible solution for reducing penetration enhancement.
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Geng, Ruibin, Shichao Wang, Xi Chen, Danyang Song, and Jie Yu. "Content marketing in e-commerce platforms in the internet celebrity economy." Industrial Management & Data Systems 120, no. 3 (January 6, 2020): 464–85. http://dx.doi.org/10.1108/imds-05-2019-0270.
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Purpose With the popularity of social media and, recently, live streaming, internet celebrity endorsements have become a prevalent approach to content marketing for e-commerce sellers. Despite the widespread use of social media and online communities, empirical studies investigating the economic value of user-generated content (UGC) and marketer-generated content (MGC) still lag behind. The purpose of this paper is to contribute both theoretically and practically to capture both first-order effects and second-order effects of internet celebrity endorsements on marketing outcomes in an e-commerce context. Design/methodology/approach This study conducts a cross-sectional regression to evaluate the economic value of internet celebrity endorsement, and a panel vector autoregressive model is adopted to examine the relationship between celebrities’ and consumers’ content marketing behaviors and e-commerce sales performance. The authors also adopt look-ahead propensity-score matching technique to correct for selection bias. Findings The empirical results show that the content generation efforts of marketers and the interaction behaviors between marketers and consumers will significantly influence the e-commerce sales, which refers to the first-order effects of internet celebrity endorsement. Moreover, interactions within the fan community exert second-order effects of content marketing on sales performance. Originality/value This paper provides new insights for e-commerce retailers to evaluate the economic values of internet celebrity endorsement, a new content marketing practice in e-commerce platform.
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Moreno-Andrade, I., and G. Buitrón. "Influence of the origin of the inoculum on the anaerobic biodegradability test." Water Science and Technology 49, no. 1 (January 1, 2004): 53–59. http://dx.doi.org/10.2166/wst.2004.0017.
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Five different sources of inocula were studied to determine its influence on biodegradability tests. Inocula were characterized determining granulometry, specific methanogenic activity, solids content, and volumetric sludge index. Also, the fermentative, aceticlastic, hydrogenophilic, OPHA, and sulfate-reducing groups were determined by the most probable number technique. Anaerobic biodegradability tests were conducted with two different substrates, one easy to degrade (glucose) and a toxic one (phenol). The best performance, in terms of percent of biodegradation and lag time, for both substrates, was obtained with the inoculum from a brewery industry UASB. The results can be explained in terms of the initial activity of the inoculum. The influence of the significant variations found in the specific methanogenic activity of the five inocula studied is discussed, in terms of the microbial composition of the samples. The results emphasized the importance of the selection of an appropriate source of inoculum in order to obtain reliable results.
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Trang, Michael, Justin C. Bader, Eric A. Ople, William G. Kramer, Michael R. Hodges, Sujata M. Bhavnani, and Christopher M. Rubino. "1340. Population Pharmacokinetic (PK) Analysis of APX001 Using Phase 1 Data." Open Forum Infectious Diseases 5, suppl_1 (November 2018): S409—S410. http://dx.doi.org/10.1093/ofid/ofy210.1172.
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Abstract Background APX001 is a novel antifungal agent which is rapidly converted to the active metabolite APX001A. APX001A exhibits in vitro activity against many clinically important yeast and fungi, including echinocandin- and azole-resistant Candida species. Given this activity, intravenous (IV) and oral (PO) formulations of APX001 are being developed for the treatment of patients with candidemia or invasive candidiasis. Phase 1 data were used to develop a population PK (PPK) model to describe the time-course of APX001A in plasma. Methods The PPK model was developed using 3,736 plasma PK samples collected from 128 healthy subjects who received APX001 single and multiple IV and PO doses ranging from 10 to 1,000 mg. Instantaneous conversion was assumed by scaling input doses by the molecular weight ratio of APX001A to APX001. After development of the structural PK model, stepwise forward and backward selection procedures were used to identify significant covariate relationships. Model qualification included standard goodness-of-fit metrics and prediction-corrected visual predictive check (PC-VPC) plots. Results A two-compartment model with zero-order IV input, or first-order PO absorption with lag time to account for the apparent delay in oral absorption, best described APX001A plasma PK. Exponential error models were used to estimate interindividual variability (IIV) for all parameters. Interoccasion variability was estimated for the absorption rate constant, bioavailability, and lag time. Body weight was identified as a statistically significant predictor of the IIV on the volume of the central and peripheral compartments. The PPK model provided an accurate and unbiased fit to the plasma data based on individual- and population-predicted concentrations (r2 = 0.977 and 0.873, respectively). The PC-VPC plots for the final PPK model (Figure 1) demonstrated good alignment between observed concentrations and the model predicted 5th, 50th, and 95th percentiles. Conclusion A PPK model describing APX001A plasma PK following IV or PO doses was successfully developed. This model will be useful for generating simulated APX001A exposures for use in pharmacokinetic–pharmacodynamic target attainment analyses to support APX001 dose selection. Disclosures M. Trang, Amplyx Pharmaceuticals, Inc.: Research Contractor, Research support. J. C. Bader, Amplyx Pharmaceuticals, Inc.: Research Contractor, Research support. E. A. Ople, Amplyx Pharmaceuticals, Inc.: Employee, Salary. W. G. Kramer, Amplyx Pharmaceuticals, Inc.: Scientific Advisor, Consulting fee. M. R. Hodges, Amplyx Pharmaceuticals, Inc.: Employee, Salary. S. M. Bhavnani, Amplyx Pharmaceuticals, Inc.: Research Contractor, Research support. C. M. Rubino, Amplyx Pharmaceuticals, Inc.: Research Contractor, Research support.
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Vinayagathasan, T., and R. Ramesh. "Do Governance Indicators Matter for Economic Growth? The Case of Sri Lanka." Indian Journal of Public Administration 65, no. 2 (June 2019): 430–50. http://dx.doi.org/10.1177/0019556119844616.
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This study attempts to identify the impact of governance indicators on economic growth using time series data for Sri Lanka from 1996 to 2016 published by the World Bank. The Phillips–Perron (PP) unit root test confirmed that all the variables are integrated in order one and suggested the use of cointegration technique to identify the long-run relationship between the variables. All the lag length selection criteria except Schwarz Information Criterion (SIC) advocated the use of one lag as an optimal lag length for this study. Johansen cointegration method detected three cointegrating relationships among the variables. Further, this technique identified a significant and positive relationship between government effectiveness (GE) and gross domestic product per capita (GDPPC) in the long run. This result is in contrast to all the three traditional approaches, such as correlation test, scatter plot and ordinary least squared (OLS), in which they do not identify any clear relationship between them. Moreover, Johansen test found a negative and statistically significant link between political stability and absence of violence (PSAV) and GDPPC in the long run, while all three traditional approaches identified a positive correlation between them. The findings of this study indicate a negative association between rule of law (ROL) and GDPPC in the long run, which coincides with theory, some of the empirical studies and with findings of all three traditional approaches used in this study. Even though OLS did not identify a significant relationship between control of corruption (COC) and GDPPC, Johansen test, correlation test and scatter plot detected a significant and negative correlation between them in the long run as expected by the theoretical evidence. Granger’s causality test identified the bidirectional causality between GE and ROL and unidirectional causality between ROL and COC. However, relationship between governance variables and GDPPC vary based on the estimation methods. These findings suggest that the policymakers need to take considerable attention on the above when they formulate and implement policy to improve GE.
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Pang, Xun. "Modeling Heterogeneity and Serial Correlation in Binary Time-Series Cross-sectional Data: A Bayesian Multilevel Model with AR(p) Errors." Political Analysis 18, no. 4 (2010): 470–98. http://dx.doi.org/10.1093/pan/mpq019.
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This paper proposes a Bayesian generalized linear multilevel model with apth-order autoregressive error process to analyze unbalanced binary time-series cross-sectional (TSCS) data. The model specification is motivated by the generic TSCS data structure and is intended to handle the associated inefficiency and endogeneity problems. It accommodates heterogeneity across units and between time periods in the form of random intercepts and random-effect coefficients. At the same time, itspth-order autoregressive error process, employed either by itself or in concert with other dynamic methods, adequately corrects serial correlation and improves statistical inference and forecasting. With a stationarity restriction on the error process, the model can also be used as a residual-based cointegration test on discrete TSCS data. This is especially valuable because cointegration testing on discrete TSCS data is methodologically challenging and rarely conducted in practice. To handle the estimation difficulties, I developed an efficient Markov chain Monte Carlo (MCMC) algorithm by orthogonalizing the error term with the Cholesky decomposition and adding an auxiliary variable. The parameter expansion method, that is, partial group move—multigrid Monte Carlo updating (PGM-MGMC), is employed to further improve MCMC mixing and speed up convergence. The paper also provides a computational scheme to approximate the Bayes's factor for the purposes of serial correlation diagnostics, lag order determination, and variable selection. Simulated and empirical examples are used to assess the model and techniques.
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Rekwot, Grace Zibah, Anosike Francis Ugo, and Oke-Egbodo Brenda Engo. "Climate Variability and Livestock Production in Nigeria: Lessons for Sustainable Livestock Production." Agricultura Tropica et Subtropica 49, no. 1-4 (December 1, 2016): 30–37. http://dx.doi.org/10.1515/ats-2016-0004.
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Abstract The study examined the relationship between climate variability and livestock production and the lessons that can be drawn for achieving sustainable livestock production in Nigeria. The study employed time series data on annual rainfall and livestock production given by index of the aggregate livestock production over the period of 1970 to 2008. The data were obtained from various publications of the Central Bank of Nigeria and the Nigerian Meteorological Agency. The data were analyzed through the instrumentality of econometric tools such as Augmented Dickey Fuller (ADF) test, Vector auto regression (VAR) lag order selection test and Pairwise granger causality. The results of the data analysis revealed the existence of unidirectional causality from climate variability to livestock production in Nigeria and this implies that climate variability has been significant in influencing livestock production over the period under study. Based on the foregoing, it is recommended as a matter of urgency that government should continually sensitize farmers on the challenges of climate change and feasible adaptation measures that they can adhere to in order to avert the detrimental effects of climate change on sustainable livestock production. In other words, implementation of the policy thrust on climate smart agriculture should be pursued vigorously.
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Lang, K. M., and R. A. Spritz. "In vitro splicing pathways of pre-mRNAs containing multiple intervening sequences?" Molecular and Cellular Biology 7, no. 10 (October 1987): 3428–37. http://dx.doi.org/10.1128/mcb.7.10.3428.
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We analyzed the in vitro splicing pathways of three multi-intervening-sequence (IVS) pre-mRNAs: human beta-globin, which contains two IVSs (K. M. Lang, V. L. van Santen, and R. A. Spritz, EMBO J. 4:1991-1996, 1985); rat alpha-lactalbumin, which contains three IVSs; and murine interleukin-3, which contains four IVSs. We found that there are highly preferred pathways of IVS removal from these multi-IVS pre-mRNAs in vitro. The three IVSs of rat alpha-lactalbumin pre-mRNA were excised sequentially from 5' to 3'; in most molecules, IVS1 was removed first, followed by IVS2 and finally by IVS3. The splicing pathway of interleukin-3 pre-mRNA in vitro was more complex. The four IVSs were excised in a highly preferred temporal order, but the order was not strictly sequential or directional. In most molecules, IVS1 and IVS4 were removed first, either simultaneously or in rapid succession. Subsequently, IVS2 was excised, followed by IVS3. The observed splicing pathways apparently resulted from differences in lag times and maximum excision rates of the different IVSs. We detected no exon skipping during splicing of these transcripts in vitro. These observations have implication for proposed models of splice site selection.
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Lang, K. M., and R. A. Spritz. "In vitro splicing pathways of pre-mRNAs containing multiple intervening sequences?" Molecular and Cellular Biology 7, no. 10 (October 1987): 3428–37. http://dx.doi.org/10.1128/mcb.7.10.3428-3437.1987.
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We analyzed the in vitro splicing pathways of three multi-intervening-sequence (IVS) pre-mRNAs: human beta-globin, which contains two IVSs (K. M. Lang, V. L. van Santen, and R. A. Spritz, EMBO J. 4:1991-1996, 1985); rat alpha-lactalbumin, which contains three IVSs; and murine interleukin-3, which contains four IVSs. We found that there are highly preferred pathways of IVS removal from these multi-IVS pre-mRNAs in vitro. The three IVSs of rat alpha-lactalbumin pre-mRNA were excised sequentially from 5' to 3'; in most molecules, IVS1 was removed first, followed by IVS2 and finally by IVS3. The splicing pathway of interleukin-3 pre-mRNA in vitro was more complex. The four IVSs were excised in a highly preferred temporal order, but the order was not strictly sequential or directional. In most molecules, IVS1 and IVS4 were removed first, either simultaneously or in rapid succession. Subsequently, IVS2 was excised, followed by IVS3. The observed splicing pathways apparently resulted from differences in lag times and maximum excision rates of the different IVSs. We detected no exon skipping during splicing of these transcripts in vitro. These observations have implication for proposed models of splice site selection.
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Oyakhilomen, Oyinbo. "Causality of Interest Rate Policy and Agricultural Production in an Atmosphere of Economic Deregulation in Nigeria." Agricultura Tropica et Subtropica 47, no. 2 (June 1, 2014): 68–71. http://dx.doi.org/10.2478/ats-2014-0009.
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Abstract This study was carried out to examine the causal relationship between interest rate policy and agricultural production in a deregulated economic setting in Nigeria using time series data covering 1987 to 2011. The data utilized include data on interest rate and agricultural production which were obtained from various publications of central bank of Nigeria. Augmented Dickey Fuller (ADF) test, Vector autoregression (VAR) lag order selection test and granger causality test were employed in the data analysis and the result indicated that market driven interest rate was not significant in influencing agricultural production over the period of deregulation and this was attributed to the substantial volatility and high market driven interest rate leading to limited accessibility to credit facilities by small scale farmers. It is recommended that the central bank of Nigeria should strongly exercise some measure of interest rate control that favours investment friendly interest rate policy that is supportive of credit mobilization for sustainable agricultural production and also the realization of the goal of Agricultural Transformation Action Plan (ATAP) in Nigeria
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Wang, Cheng-Chi, Cheng-Hung Lee, Ning-Chien Chin, Kun-Hui Chen, Chien-Chou Pan, and Kuo-Chih Su. "Biomechanical analysis of the treatment of intertrochanteric hip fracture with different lengths of dynamic hip screw side plates." Technology and Health Care 28, no. 6 (November 17, 2020): 593–602. http://dx.doi.org/10.3233/thc-202248.
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BACKGROUND: Dynamic hip screw (DHS) is a common implant used to treat stable-type intertrochanteric hip fractures. There are many factors that can affect the success rate of the surgery, including the length of side plates. It is therefore important to investigate the biomechanical effect of different DHS side plates on bones. OBJECTIVE: In order to reduce the likelihood of an implant failure, the aim of this study was to use finite element analysis (FEA) to investigate and understand the effect of side plates with different lengths in DHS. METHODS: In this FEA study, a 3D model with cortical bone, cancellous bone, side plate, lag screw, and cortical screws to simulate the implantation of DHS with different lengths of side plate (2-hole, 4-hole, and 6-hole) for intertrochanteric hip fractures was constructed. The loading condition was used to simulate the force (400 N) on the femoral head and the stress distribution on the lag screw, side plate, cortical screws, and femur was measured. RESULTS: The highest stress points occured around the region of contact between the screw and the cortical bones. The stress on the femur at the most distal cortical screw was the greatest. The shorter the length of the side plate, the greater the stress on the cortical screws, resulting in an increased stress on the femur surrounding the cortical screws. CONCLUSIONS: The use of DHS with 2-hole side plate may increase the risk of side plate pull-out. The results of this study provide a biomechanical analysis for selection of DHS implant lengths that can be useful for orthopaedic surgeons.
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Ryabchikov, M. Yu, E. S. Ryabchikova, and S. A. Filippov. "A Fuzzy Logic-Based System for Controlling the Temperature of Steam Exiting a Superheater for the Purpose of Preemptive Perturbation Compensation." Mekhatronika, Avtomatizatsiya, Upravlenie 22, no. 4 (April 5, 2021): 181–90. http://dx.doi.org/10.17587/mau.22.181-190.
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This paper discusses the issue of adjusting the temperature of steam exiting a superheater in an environment that is affected by perturbations due to the sudden and significant fluctuations in the inlet steam temperature. Using the superheater at the Magnitogorsk Iron & Steel Works as an example, we highlight that a slow response to the aforementioned perturbations in the systems that adjust for deviations leads to undesired rises and drops in the outlet steam temperature. We review the current suggestions on adjusting the temperature of steam exiting a superheater and determine the main reasons behind the drop in adjustment quality. These reasons are related to a significant lag and the variability of the control object’s features, which make preemptive perturbation control difficult. In order to control such environments, we propose a system with two degrees of freedom, which combines a proportional-integral controller and a fuzzy logic-based controller. In the system that we are proposing, the changes in the controlled parameter (depending on the input value) are adjusted within the main loop that has a standard controller and negative feedback, while the perturbations are removed by using a secondary loop, which also has negative feedback, a fuzzy logic-based controller, and a simulation of the object without the component that accounts for the lag. For situations when the information on the object’s features is precise, we describe the specifics of the loops’ interaction, specifically in cases when the task processing loop does not respond to the perturbations in the inlet steam temperature, thus allowing for setting up the loops’ controllers separately. In situations when the inlet steam temperature is experiencing perturbations, the impact of the lag on adjustment quality only becomes evident when the trajectory of the transition process shifts along the time scale by a lag value, which is completely in line with the Smith predictor principles. The system is focused on synthesizing the fuzzy logic rules and refining the parameters of the simulation used for adjustment purposes, based on the results of automated computer-aided control simulation. We propose a structural modification of the control system that makes it possible to compensate for any residual control errors caused by the non-linear structure of the fuzzy controller; this reduces the number of requirements for those set-up parameters where the value selection is based on the needs of simulation modeling, which requires a lot of computing resources. We demonstrate the results of simulation experiments that compare the efficiency of control using the system suggested and the efficiency of control using a system with a standard controller only. The computer simulation was performed in the MATLAB Simulink environment. We reaffirm that a combined control system performs better when adjusting the steam temperature.
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Parveen, Shabana, Bibi Aisha Sadiqa, Sher Ali, and Farrah Yasmin. "Impact of Private Investment, Economic Growth and Financial Development on Environmental Degradation: Evidence from Pakistan." Review of Economics and Development Studies 7, no. 1 (March 20, 2021): 13–24. http://dx.doi.org/10.47067/reads.v7i1.313.
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Private investment plays an important role in the process of economic growth and also impact natural environment of a country. The main purpose of the present study is to empirically analyze the impact of private investment and other macro economic variables on environmental degradation of Pakistan. For the purpose, time series data is collected for the years 1975 to 2017. The study used Linear regression model for analyzing the impact of private investment, energy consumption, financial development and economic growth on environmental degradation. Augmented Dickey Fuller (ADF) test and Phillips Perron (PP) test is used for identifying the unit root of the variables; first with an intercept then, with an intercept and a linear deterministic trend. Akaike Information Criterion (AIC) is used for selection of optimum lag whereas Johansen cointegration test is adopted for analyzing long run association in the variables. The results of linear regression model show that energy consumption and economic growth have a positive and statistically significant impact on CO2 emissions whereas the impact of private investment on CO2 emissions is negative. It means that in Pakistan, private investment is environment friendly. Based on study results, it is recommended that when formulating policies for economic growth and development, motivation should be given to private inverters in order to increase private investment.
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Hartbauer, M., L. Haitzinger, M. Kainz, and H. Römer. "Competition and cooperation in a synchronous bushcricket chorus." Royal Society Open Science 1, no. 2 (October 2014): 140167. http://dx.doi.org/10.1098/rsos.140167.
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Synchronous signalling within choruses of the same species either emerges from cooperation or competition. In our study on the katydid Mecopoda elongata , we aim to identify mechanisms driving evolution towards synchrony. The increase of signal amplitude owing to synchronous signalling and the preservation of a conspecific signal period may represent cooperative mechanisms, whereas chorus synchrony may also result from the preference of females for leading signals and the resulting competition for the leader role. We recorded the timing of signals and the resulting communal signal amplitudes in small choruses and performed female choice experiments to identify such mechanisms. Males frequently timed their signals either as leader or follower with an average time lag of about 70 ms. Females selected males in such choruses on the basis of signal order and signal duration. Two-choice experiments revealed a time lag of only 70 ms to bias mate choice in favour of the leader. Furthermore, a song model with a conspecific signal period of 2 s was more attractive than a song model with an irregular or longer and shorter than average signal period. Owing to a high degree of overlap and plasticity of signals produced in ‘four male choruses’, peak and root mean square amplitudes increased by about 7 dB relative to lone singers. Modelling active space of synchronous males and solo singing males revealed a strongly increased broadcast area of synchronous signallers, but a slightly reduced per capita mating possibility compared with lone singers. These results suggest a strong leader preference of females as the ultimate causation of inter-male competition for timing signals as leader. The emerging synchrony increases the amplitude of signals produced in a chorus and has the potential to compensate a reduction of mating advantage in a chorus. We discuss a possible fitness benefit of males gained through a beacon effect and the possibility that signalling as follower is stabilized via natural selection.
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Kettunen, Pyry. "Experiment on People’s Selection of Route Landmarks from Different Types of Geospatial Pictures." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-172-2019.
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<p><strong>Abstract.</strong> Different types of geospatial pictures, such as maps and aerial imagery, have varying potential to provide spatial knowledge for the viewers. Our earlier review has assessed different common types of geopictures with regard to their support for acquiring different types of spatial knowledge (Kettunen et al., 2012). The assessment was based on previous literature about geopicture experiments as well as analytical itemization of the information available on the pictures as a function of picture characteristics, namely vantage point, number of visible vertical features, and visual realism. In addition to the actual assessment, the review concluded that there is an important shortage of empirical evaluations on spatial knowledge acquisition from geopictures, which lag we are addressing with the experiment described here.</p><p>The aim of the experiment is to find out what kind of geospatial features, or landmarks (see Presson and Montello, 1988; Richter and Winter, 2014), people read from geopictures, does reading differ between pictures, and how does it differ. For the experimental task, we chose a common map activity of planning navigation for walking through an urban route. The stimuli are five different types of common geopictures with both aerial vertical and aerial oblique vantage points as well as with both abstract and photorealistic levels of visual realism (Figure 1). Five routes are to be planned in different areas of city of Helsinki so that a different geopicture type is shown for each route. The pictures are shown as corridors surrounding the shortest walking route.</p><p>The participants have been recruited from expert and non-expert social media groups and e-mail lists, being called to be over 18 years old. The background questionnaire has asked about their age, gender, possible visual disorders, and frequency of use for each type of map in the experiment.</p><p>The experimental design for measuring the effect of geopicture type was built randomized and between-participants so that each participant completes series of five pictures, each of different type, in randomized order, and from different geographical areas. Two rounds of five pictures are shown: first, to measure the actual selection of landmarks, and second, to investigate the level of recall of the selected landmarks later. The procedure of the experiment is the following (Figure 2): 1) Introduction, 2) Consent to participate, 3) Training trial of the landmark selection task (1 picture), 4) Testing trials of the landmark selection task (5 pictures), 5) Training trial of the selection recall task (1 picture), 6) Testing trials of the landmark selection task (5 pictures), 7) Background questionnaire, and 8) Thanks and feedback. The Start and End points of the routes are drawn on the pictures (Figure 1) and the participants are asked to plan the shortest route between the points along roads and paths, to point 3–7 features along the route in navigation route for being able to navigate the route, and to enter common names for the features after pointing each feature. Response times, pointed coordinates, and feature names are recorded in order to analyze the participants’ answers.</p><p>The presentation at the ICC2019 conference will introduce preliminary results of the conducted experiment, reflect them on the previous studies on maps and routing and discuss their implications on the design of map contents from the viewpoint of route planning. The results will build empirical foundation about differences in reading of geospatial picture types, and for selecting appropriate features to be drawn on maps.</p>
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Hassani, Hossein, and Mohammad Reza Yeganegi. "Selecting optimal lag order in Ljung–Box test." Physica A: Statistical Mechanics and its Applications 541 (March 2020): 123700. http://dx.doi.org/10.1016/j.physa.2019.123700.
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Сенина, E. Senina, Прохорцов, A. Prokhortsov, Ивахно, N. Ivakhno, Федоров, and S. Fedorov. "Method for Registering Movement of the Chest at the Diagnosis of the Sleep Apnea." Journal of New Medical Technologies 21, no. 4 (October 8, 2014): 133–37. http://dx.doi.org/10.12737/7286.
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The paper considers the actual problem of the development of instrumental methods of examination and diagnostics of carotid apnea. These methods don’t require the constant presence of health personnel and the expensive equipment. The authors proposed a method of registering movement of the chest using a micromechanical accelerometer with extremely small dimensions, low weight, power consumption and cost, along with sensor control oro-nasal flow and pulse oximeter, it allows the recognition of the type of apnea. During experimental studies, the accelerometer was placed on the chest, measuring the total vector acceleration due to the movement of the chest and the acceleration of free fall. Mathematical modeling of signal processing has allowed the optimal lowpass filter Butterworth 6th order, ensuring the selection of the useful signal. The article presents the results of measuring the acceleration along the x-axis and z-axis with continuous breathing and temporary stop. The results of measuring acceleration along three axes showed that the most significant for registration are the x-axis and z-axis. The use of proposed method of measuring the motion of the thorax by means of accelerometers allows to detecting the cessation of breathing, the time lag isn’t more than 0.5 seconds. This method can be used in addition to the pulse oximeter sensors and oro-nasal flow, which will provide registration apnea.
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Lu, Yanhui, Vineet Goti, Ayyappa Chaturvedula, Jessica E. Haberer, Michael J. Fossler, Mark E. Sale, David Bangsberg, Jared M. Baeten, Connie L. Celum, and Craig W. Hendrix. "Population Pharmacokinetics of Tenofovir in HIV-1-Uninfected Members of Serodiscordant Couples and Effect of Dose Reporting Methods." Antimicrobial Agents and Chemotherapy 60, no. 9 (June 27, 2016): 5379–86. http://dx.doi.org/10.1128/aac.00559-16.
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ABSTRACTAntiretroviral preexposure prophylaxis (PrEP) with once-daily dosing of tenofovir and tenofovir-emtricitabine was shown to be effective for preventing HIV-1 infection in individuals who had HIV-1-seropositive partners (the Partners PrEP Study). We developed a population pharmacokinetic model for tenofovir and investigated the impacts of different dose reporting methods. Dosing information was collected as patient-reported dosing information (PRDI) from 404 subjects (corresponding to 1,280 drug concentration records) from the main trial and electronic monitoring-based adherence data collected from 211 subjects (corresponding to 327 drug concentration records) in an ancillary adherence study. Model development was conducted with NONMEM (7.2), using PRDI with a steady-state assumption or using PRDI replaced with electronic monitoring records where available. A two-compartment model with first-order absorption was the best model in both modeling approaches, with the need for an absorption lag time when electronic monitoring-based dosing records were included in the analysis. Age, body weight, and creatinine clearance were significant covariates on clearance, but only creatinine clearance was retained in the final models per stepwise selection. Sex was not a significant covariate on clearance. Tenofovir population pharmacokinetic parameter estimates and the precisions of the parameters from the two final models were comparable with the point estimates of the parameters, differing from 0% to 35%, and bootstrap confidence intervals widely overlapped. These findings indicate that PRDI was sufficient for population pharmacokinetic model development in this study, with a high level of adherence per multiple measures.
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Tasman, Abel. "Capital Buffer dan Faktor Penentunya di Indonesia." Jurnal Inovasi Pendidikan Ekonomi (JIPE) 10, no. 2 (November 30, 2020): 132. http://dx.doi.org/10.24036/011098000.
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Capital buffer is defined as the difference between the bank's capital ratio and the capital adequacy ratio (Capital Adequacy Ratio) or CAR imposed by the Central Bank. Capital buffers can be used as capital reserves in times of various economic shocks so as to minimize risks faced by banks. A bank that has a high capital buffer reflects a high CAR as well, while a CAR that is too high is also not profitable for the bank, because this capital should be used for lending and investing in an effort to maximize profits. This study aims to determine the determinants of going public banking capital buffer in Indonesia for the period 2014 to 2018. The sample selection is based on purposive. Acting as the dependent variable is the capital buffer and the independent variables are ROE, NPL, Lag of capital buffer (〖BUFF〗 _ (t-1)), Size and GDP. This study used multiple regression analysis. The results of this study indicate that the selected determinants of the capital buffer of going public banking in Indonesia are adjustment costs and the business cycle. Adjustment costs have a positive and significant effect on the capital buffer of going public banking in Indonesia and the business cycle has a negative and significant effect on the capital buffer of go public banking. public in Indonesia. Thus, the sample companies can optimize their capital buffer which can be ideal in order to maximize profits by considering the two factors above.
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MATARAGAS, M., E. H. DROSINOS, P. SIANA, P. SKANDAMIS, and I. METAXOPOULOS. "Determination of the Growth Limits and Kinetic Behavior of Listeria monocytogenes in a Sliced Cooked Cured Meat Product: Validation of the Predictive Growth Model under Constant and Dynamic Temperature Storage Conditions." Journal of Food Protection 69, no. 6 (June 1, 2006): 1312–21. http://dx.doi.org/10.4315/0362-028x-69.6.1312.
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To describe the growth limits of Listeria monocytogenes NCTC10527 in a sliced vacuum-packaged cooked cured meat product, the binary logistic regression model was used to develop an equation to determine the probability of growth or no growth of L. monocytogenes as a function of temperature (from 0 to 10°C) and water activity (from 0.88 to 0.98). Two inoculum concentrations were used (10 and 104 CFU g−1), and the growth limits for the two inocula were different. The kinetic behavior of L. monocytogenes as a function of temperature (4, 8, 12, and 16°C) on the same meat product at the lower concentration (10 CFU g−1) was also studied. The Baranyi model appeared to fit the overall experimental data better than did the modified Gompertz and the modified logistic models. Maximum specific growth rate (μmax), lag phase duration (LPD), and maximum cell concentration (Nmax) derived from the primary model were modeled using the square root function (μmax and LPD) and a second order polynomial (Nmax) (secondary models). The selection of the best model (primary or secondary) was based on some statistical indices (the root mean square error of residuals of the model, the regression coefficient, the F test, the goodness of fit, and the bias and accuracy factor). The developed kinetic behavior model was validated under constant and dynamic temperature storage conditions. This prediction of L. monocytogenes growth provides useful information for improving meat safety and can be used for in-depth inspection of quality assurance systems in the meat industry.
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Shabana Parveen, Abdul Qayyum Khan, and Sohail Farooq. "The Causal Nexus of Urbanization, Industrialization, Economic Growth and Environmental Degradation: Evidence From Pakistan." Review of Economics and Development Studies 5, no. 4 (December 31, 2019): 721–30. http://dx.doi.org/10.26710/reads.v5i4.883.
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The paper analyzes the causal relation between eeconomic growth, urbanization, industrialization and environmental degradation of Pakistan. The study used time series data for the sample span of 1975-2017, retrived from World Bank Development Indicators (WDI, 2017). Vector Auto Regressive (VAR) model is used for analyzing the causal link amongst the variables, namely economic growth, urbanization, industrialization and environmental degradation. The Granger causality test is used for identifying the order of the causal association. Before estimating VAR, Augmented Dickey Fuller (ADF) as well as Phillips Perron (PP) tests are used for confirming the stationarity characteristic of all variables, first with intercept and then, with intercept along with a linear deterministic trend. Akaike Information Criterion (AIC) is used for selection of optimum lag. The Johansen Cointegration test is adopted for identifying long run associations. The result of the VAR model reveals, If any innovation of one standard deviation from outside the model occurred, it will take about 13 years for CO2, 19 years for urbanization,16 years for industrialization and about 12 years for economic growth in adjustment. These results further indicate that most of the variation in all variables is explained in their own. The study confirmed two unilateral causalities, that is runs from CO2 to urbanization as well as economic growth. The findings of the research work propose that policy makers required to develop policy helpful to the environment which will encourage verifiable economic growth in Pakistan. The policy makers need to plan for environmental issue while making policies regarding urbanization, industrialization and economic growth.
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Manoharan J, Samuel. "Flawless Detection of Herbal Plant Leaf by Machine Learning Classifier Through Two Stage Authentication Procedure." June 2021 3, no. 2 (June 22, 2021): 125–39. http://dx.doi.org/10.36548/jaicn.2021.2.005.
Full textAbstract:
Herbal plants are crucial to human existence for medical reasons, and they can also provide free oxygen to the environment. Many herbal plants are rich in therapeutic goods and also it includes the active elements that will benefit future generations. Many valuable plant species are being extinguished and destroyed as a result of factors such as global warming, population growth, occupational secrecy, a lack of government support for research, and a lack of knowledge about therapeutic plants. Due to the lag of dimensional factors such as length and width, many existing algorithms fail to recognize herbal leaf in all seasons with the maximum accuracy. Henceforth, the proposed algorithm focuses on the incomplete problems in the datasets in order to improve the detection rate for herbal leaf identification. The inclusions of dimension factors in the datasets are performing good results in the image segmentation process. The obtained result has been validated with a machine learning classifier when combined with ex-or gate operation is called deep knowledge-based identification. This two-stage authentication (TSA) procedure is improving the recognition rate required for the detection of herbal leaf. This fusion of image segmentation with machine learning is providing good robustness for the proposed architecture. Besides, intelligent selection of image segmentation techniques to segment the leaf from the image is improving the detection accuracy. This procedure is addressing and answering the drawbacks associated with the detection of the herbal leaf by using many Machine Learning (ML) approaches. Also, it improves the rate of detection and minimizes the classification error. From the results, it is evident that the proposed method has obtained better accuracy and other performance measures.
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Grinchel, Boris, and Evgeniya Nazarova. "Competitive Attractiveness of Regions as a Target of Development Strategies." Regionalnaya ekonomika. Yug Rossii, no. 1 (April 2021): 42–53. http://dx.doi.org/10.15688/re.volsu.2021.1.4.
Full textAbstract:
The article discusses the competitive attractiveness and improvement of the characteristics of the regions’ social and economic space that may attract resources and consumers. Competitiveness in such progress ensures the acceleration of the overall development of the country and individual territories. The article substantiates and tests by data from the Russians regions of the Southern Federal District the hypothesis that an increase in certain characteristics of competitive attractiveness in areas which are relevant for a given region and currently in demand by external and internal consumers can be identified and selected as the goals of strategic plans the achievement of which can be controlled and monitored. The aim of the study is to develop and test a methodology for assessment and analysis of the competitive attractiveness of the regions for the selection of their target development priorities. The goal is implemented by means of developing methodological tools and testing through the analysis of the competitive potential of territories. The methodology is based on a set of social and economic factors such as economy, innovation and quality of life. In order to take into account the interdependence of factors while developing strategic plans, the authors provide a matrix of correlations of estimates according to the innovation factor of the competitive potential with the estimates of other factors and an integrated assessment of the factors mentioned above. The analysis of the assessments of regions’ competitive attractiveness made it possible to come to the conclusion that the greatest lag and differentiation in terms of indicators among territories is observed in the regions of the South of Russia from the point of view of the innovation potential and innovative attractiveness. Regional authorities can take into account the results of this research while developing strategies for the regions.
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Hasan, Arshad, and Zafar Mueen Nasir. "Macroeconomic Factors and Equity Prices: An Empirical Investigation by Using ARDL Approach." Pakistan Development Review 47, no. 4II (December 1, 2008): 501–13. http://dx.doi.org/10.30541/v47i4iipp.501-513.
Full textAbstract:
The relationship between macroeconomic variables and the equity prices has attracted the curiosity of academicians and practitioners since the publication of seminal paper of Chen, et al. (1986). Many empirical studies those tested the relationship reveal that asset pricing theories do not properly identify macroeconomic factors that influence equity prices [Roll and Ross (1980); Fama (1981); Chen, et al. (1986); Hamao (1986); Faff (1988); Chen (1991); Maysami and Koh (2000) and Paul and Mallik (2001)]. In most of these studies, variable selection and empirical analyses is based on economic rationale, financial theory and investors’ intuition. These studies generally apply Eagle and Granger (1987) procedure or Johanson and Jusilieus (1990, 1991) approach in Vector Auto Regressor (VAR) Framework. In Pakistan, Fazal (2006) and Nishat (2001) explored the relationship between macroeconomic factors and equity prices by using Johanson and Jusilieus (1990, 1991) procedure. The present study tests the relationship between macroeconomic variables such as inflation, industrial production, oil prices, short term interest rate, exchange rates, foreign portfolio investment, money supply and equity prices by using Auto Regressive Distributive Lag (ARDL) bounds testing procedure proposed by Pesaran, Shin, and Smith (1996, 2001). The ARDL approach in an errorcorrection setting has been widely applied to examine the impact of macroeconomic factors on economic growth but it is strongly underutilised in the capital market filament of literature. This methodology has a number of advantages over the other models. First, determining the order of integration of macroeconomic factors and equity market returns is not an important issue here because the Pesaran ARDL approach yields consistent estimates of the long-run coefficients that are asymptotically normal irrespective of whether the underlying regressors are I(0) or I(1) and of the extent of cointegration. Secondly, the ARDL approach allows exploring correct dynamic structure while many econometric procedures do not allow to clearly distinguish between long run and short run relationships.
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Jha, Abhishek. "Identification of the Factors for the Selection of Cement Brands by Construction Companies and Selection of Optimal Cement Brand using TOPSIS for Kathmandu Valley along with the Physical Strength Comparison of Various Cement Brands." Journal of Advanced Research in Civil and Environmental Engineering 07, no. 3&4 (November 27, 2020): 1–16. http://dx.doi.org/10.24321/2393.8307.202004.
Full textAbstract:
Cement comprises major proportion in any construction materials and the right selection of cement is equally important for construction companies. The objective of this research is to find the criteria used by the construction companies in cement selection and using the required criteria adopt TOPSIS (Technique of Order Preference by Similarity to Ideal Solution) as Multi Criteria Decision Making method for the selection of optimal cement brand among various cement brands for the construction projects in Kathmandu. Another objective is to find the physical characteristics of the selected cement brands in laboratory. For the methodology, non-random sampling was adopted. Data were collected by questionnaire, semi-structured interviews, KII and Lab test. For physical characteristics comparison of cement brands, samples were collected from hardware shop and lab test were conducted in private lab. For the factors in cement selection quality, ex-factory rate, credit-terms, delivery-time, relationship, self-clinker production, production-capacity, technology and financial-conditions were identified and ranked in relevant order. Six factors were chosen for TOPSIS for the six cement brands for Kathmandu valley. From TOPSIS, it was foundSarbottam cement is best suited for projects in Kathmandu valley in terms of physical strength Hongshi had the highest 3 and 7 days of compressive strength where as Sarbottam had highest 28 days strength. Maruti cement had longest setting time whereas United cement had shortest setting time. 28 days strength of all the cement were as per the NS 49whereas except for Maruti and Shivam, all the brands had strength as per IS 8112 criteria.