Journal articles: 'Tightness of Performance'

1

Fletcher, James W. A., Lisa Wenzel, Verena Neumann, R. Geoff Richards, Boyko Gueorguiev, Harinderjit S. Gill, Ezio Preatoni, and Michael R. Whitehouse. "Surgical performance when inserting non-locking screws: a systematic review." EFORT Open Reviews 5, no. 1 (January 2020): 26–36. http://dx.doi.org/10.1302/2058-5241.5.180066.

Full text

Abstract:

Billions of screws are inserted by surgeons each year, making them the most commonly inserted implant. When using non-locking screws, insertion technique is decided by the surgeon, including how much to tighten each screw. The aims of this study were to assess, through a systematic review, the screw tightness and rate of material stripping produced by surgeons and the effect of different variables related to screw insertion. Twelve studies were included, with 260 surgeons inserting a total of 2793 screws; an average of 11 screws each, although only 1510 screws have been inserted by 145 surgeons where tightness was measured – average tightness was 78±10% for cortical (n = 1079) and 80±6% for cancellous screw insertions (n = 431). An average of 26% of all inserted screws irreparably damaged and stripped screw holes, reducing the construct pullout strength. Furthermore, awareness of bone stripping is very poor, meaning that screws must be considerably overtightened before a surgeon will typically detect it. Variation between individual surgeons’ ability to optimally insert screws was seen, with some surgeons stripping more than 90% of samples and others hardly any. Contradictory findings were seen for the relationship between the tightness achieved and bone density. The optimum tightness for screws remains unknown, thus subjectively chosen screw tightness, which varies greatly, remains without an established target to generate the best possible construct for any given situation. Work is needed to establish these targets, and to develop methods to accurately and repeatably achieve them. Cite this article: EFORT Open Rev 2020;5:26-36. DOI: 10.1302/2058-5241.5.180066

APA, Harvard, Vancouver, ISO, and other styles

2

Curran, Hannah, and Stella Chapman. "Performance enhancing or unnecessary pressure?" Equine Health 2019, no. 47 (May 2, 2019): 26–31. http://dx.doi.org/10.12968/eqhe.2019.47.26.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Zheng, Xiao Tao, Jia Lin Zi Pan, and Jiu Yang Yu. "Effect of Gasket Compression Resilience on the Tightness of Bolted Flange System." Applied Mechanics and Materials 853 (September 2016): 328–34. http://dx.doi.org/10.4028/www.scientific.net/amm.853.328.

Full text

Abstract:

Gasket is an important sealing element of bolted flange connection structure. The nonlinear performance of the gasket material will make the flange angle and gasket compression force change. Therefore, it plays an important role in the tightness of bolted flange connection system. Apart from acknowledgment of this effect, there exists no established design calculation procedure that accounts for tightness. In this paper, the mechanical properties of the gasket at room temperature were studied, it is known that the rebound performance of the gasket is related to the initial preload. And the effect of the compressive resilience of the gasket on the tightness of the bolt flange system was discussed. The tightness of the bolt flange system can be achieved by adjusting the initial preload and working pressure of the gasket, it provides the basis for design and evaluate the tightness of bolted flange connection system.

APA, Harvard, Vancouver, ISO, and other styles

4

Kim, Hyun-Bae, Joo-Saeng Park, Jung-Pyo Hong, Jung-Kwon Oh, and Jun-Jae Lee. "Air Tightness Performance of Residential Timber Frame Buildings." Journal of the Korean Wood Science and Technology 42, no. 2 (March 25, 2014): 89–100. http://dx.doi.org/10.5658/wood.2014.42.2.89.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Zhang, Yan, Julien S. Baker, Xuejun Ren, Neng Feng, and Yaodong Gu. "Metatarsal strapping tightness effect to vertical jump performance." Human Movement Science 41 (June 2015): 255–64. http://dx.doi.org/10.1016/j.humov.2015.03.013.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Zhang, Zhixin, Qiang Guo, and Wei Liu. "Evaluation of Long-Term Tightness of the Coal Pillar Dam of Underground Reservoir and Protection Countermeasures." Energies 15, no. 19 (October 1, 2022): 7229. http://dx.doi.org/10.3390/en15197229.

Full text

Abstract:

The coal mine underground reservoir is an effective facility for mine groundwater utilization in water-deficient and ecologically fragile areas. Usually, the artificial reserved coal pillar is used as the dam of underground reservoir, and little research has been done on its tightness performance. Comsol software is used to simulate the leakage of underground reservoirs in Shendong area, in the western part of China, and the long-term tightness of coal pillar dam under different operation conditions is evaluated. The results show that: (1) When the underground reservoir is not connected with the upper water system, the coal pillar dam has good tightness performance. When they are connected, the leakage of reservoir increased due to the raised water level, and the deeper the burial depth, the greater the leakage amount. (2) When reservoir is pumping and storing water, the leakage is only half of that under constant water pressure storage, indicating that this operation mode is beneficial to the long-term tightness of a coal pillar dam. (3) With the increase of the permeability of a coal pillar dam, the leakage will be aggravated. It is suggested that the permeability of a coal pillar dam should not exceed 1 × 10−15 m2. (4) The tightness of the coal pillar dam damaged by brine immersion is greatly reduced. With only 3 m of soaking damage distance, the total leakage is twice that of the undamaged one. For a coal pillar dam with poor tightness, some protection countermeasures are proposed to reduce the reservoir water level or improve the anti-seepage performance of a coal pillar dam, so as to ensure the long-term tightness of the dam. This research can provide theoretical support and technical guidance for evaluating the seepage stability of a coal pillar dam in an underground reservoir and strengthening its seepage control.

APA, Harvard, Vancouver, ISO, and other styles

7

Cao, Shuanghua, Zhiliang Lou, Leheng Wang, and Minsi Li. "The Research of Building Air Permeability Based on Building Structural Tightness." Advanced Materials Research 594-597 (November 2012): 2142–45. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.2142.

Full text

Abstract:

The building air permeability plays a major role in both building energy performance and indoor air quality. The performance of structural tightness is set as an evaluation index of building air permeability, which is employed to analyze the relationship among building air permeability, building construction and window/door air permeability. Based on some assumptions, the coefficient of building structural tightness is established to summarize the influential factors on building air permeability, and the theory method is provided to improve the building air permeability. A model of air permeability for a small room is taken as an example. The results indicate that the building structural tightness coefficient is available to analyze the building air permeability.

APA, Harvard, Vancouver, ISO, and other styles

8

Dai, Li, and Yi Zhang. "The Influences of Material and Structure on the UV Protection of Summer Fabrics." Advanced Materials Research 298 (July 2011): 73–77. http://dx.doi.org/10.4028/www.scientific.net/amr.298.73.

Full text

Abstract:

Thin summer fabrics without anti-UV finishing were used as experimental samples and the influences of fabric thickness, tightness, structure and fiber on the anti-UV properties were observed carefully. The measured performance parameters were normalized, to make UV protection properties of different thickness, tightness, fabric structures and fiber materials are comparable. This investigation revealed that the dominant factors affecting fabric anti-ultraviolet property were fabric structure, thickness and fiber type. The anti-UV performance from strong to weak is satin, twill and plain weave in terms of fabric structure; and polyester, silk, hemp and cotton in terms of fiber material. In addition, the anti-UV performances of fabrics positively increase with their thickness, when the other parameters were kept the same.

APA, Harvard, Vancouver, ISO, and other styles

9

Cheatham, Scott W., Kyle R. Stull, Mike Fantigrassi, and Ian Montel. "Hip Musculoskeletal Conditions and Associated Factors That Influence Squat Performance: A Systematic Review." Journal of Sport Rehabilitation 27, no. 3 (May 1, 2018): 263–73. http://dx.doi.org/10.1123/jsr.2016-0246.

Full text

Abstract:

Context: The squat is a fundamental movement for weightlifting and sports performance. Both unilateral and bilateral squats are also used to assess transitional and dynamic lower-extremity control. Common lower-extremity conditions can have an influence on squat performance. Of interest are the effects of hip musculoskeletal conditions and associated factors, such as hip muscle pain, fatigue, and tightness, on squat performance. Currently, there has been no appraisal of the evidence regarding the association of these conditions and associated factors on squat performance. Objective: This study evaluated the current evidence regarding common hip musculoskeletal conditions and associated factors, such as hip muscle pain, fatigue, and tightness, on squat performance. Evidence Acquisition: A systematic review was conducted according to preferred reporting items for systematic reviews and meta-analyses guidelines. A search of PubMed, CINAHL, SPORTDiscus, ProQuest, and Google Scholar® was conducted in October, 2016 using the following keywords alone and in combination: hip, joint, arthritis, pain, range of motion (ROM), fatigue, tightness, pathology, condition, muscle, intraarticular, extraarticular, femoroacetabular impingement, single leg, bilateral, squat, performance, and technique. The grading of studies was conducted using the Physiotherapy Evidence Database scale. Evidence Synthesis: The authors identified 35 citations, 15 of which met the inclusion criteria. The qualifying studies yielded a total of 542 subjects (160 men and 382 women; mean age = 29.3 (5.9) y) and measured performance with either the barbell squat, step down, bilateral, or single-leg squat. Femoroacetabular impingement and hip arthroscopy were the only hip conditions found that affected the squat. Associated factors, such as muscle pain, fatigue, and tightness, also influenced squat performance. Conclusion: This review found that common hip conditions and associated factors and their effects on squat performance to be underinvestigated. Future research should focus on the association between common hip conditions and squat performance.

APA, Harvard, Vancouver, ISO, and other styles

10

Liu, Long Bin, Pan Pan Mi, Shuai Cao, and Ming Yun Lv. "Ground Simulation Method for Envelope Performance of Airship in near Space." Advanced Materials Research 989-994 (July 2014): 3473–76. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.3473.

Full text

Abstract:

Performing characteristics on envelope composite of near space airship (NSA) are quite different from that of the low altitude airship essentially. The NSA envelope material should meet excellent applicative characteristics including light weight, high strength, anti-aging, anti-ultraviolet radiation, gas-tightness, weather resistance. Ground simulation test is critical for the envelope design and development process of NSA, and the environmental features of near space is analyzed for NSA, then corresponding ground simulation test methods are proposed to involve mechanical strength of the ground test methods among the changing weather temperature and over pressure changes, materials weather resistance and air tightness test. Finally the coupling relationship between various mechanical test and environmental test methods is also investigated.

APA, Harvard, Vancouver, ISO, and other styles

11

Kulkarni, Swapnil G., Harshada R. Patil, and Akshay A. Chougule. "Effect of Muscle Energy Technique on Kicking Speed in Football Players with Hamstring Tightness - An Experimental Study." International Journal of Health Sciences and Research 11, no. 7 (July 12, 2021): 44–50. http://dx.doi.org/10.52403/ijhsr.20210707.

Full text

Abstract:

Background: Football is a dynamic sport that requires athlete to perform many different movements and skills such as rapid acceleration and deceleration, jumping, kicking, and sliding, quick changes of directions. Hamstring muscle injury being the commonest injury is due to hamstring tightness. Prevalence of hamstring injury is common in football players because of its tightness. Muscle energy technique helps in increasing Hamstring flexibility of football players with hamstring tightness. Purpose of Study: The purpose of this study was to find out the effect of Muscle energy technique on kicking speed in football players with hamstring tightness. The players were given 6 days Muscle energy technique on hamstring muscle to improve its flexibility. Kicking speed time was checked pre and post Muscle energy technique. Materials and Methodology: Football players with hamstring tightness [n=40] were included in this study. Muscle energy technique was given for hamstring tightness for 6 days. Pre and post kicking speed time of the players were noted. Result: There was decrease in kicking speed time of the players when compared with pre [0.785] and post [0.4450] Muscle energy technique was proved statistically significant [p=0.000]. Conclusion: It is concluded that Muscle energy technique helps in decreasing the kicking speed time i.e. the ball will cover the given distance in shorter period of time in football players with hamstring tightness and hence helps in bringing out their best performance on field. Key words: Muscle energy technique [MET], Hamstring tightness, kicking speed time.

APA, Harvard, Vancouver, ISO, and other styles

12

Teng, Yue, Ho Yeon Lee, Haesu Lee, and Yoon Ho Lee. "Effect of Sputtering Pressure on the Nanostructure and Residual Stress of Thin-Film YSZ Electrolyte." Sustainability 14, no. 15 (August 6, 2022): 9704. http://dx.doi.org/10.3390/su14159704.

Full text

Abstract:

Solid oxide fuel cells are energy conversion devices that contribute to carbon neutrality, with the advantages of high efficiency, clean emissions production, and distributed power generation. However, the high operating temperature of the solid oxide fuel cells causes system stability and material selection problems. In this study, we aimed to lower the operating temperature of a solid oxide fuel cell by reducing the thickness of the electrolyte via sputtering. The deposition process was conducted under various pressure conditions to find the optimal sputtering process for a gas-tight YSZ thin-film electrolyte. The gas-tightness of the YSZ electrolytes was evaluated by observing the nanostructure and cell performance. As a result, the YSZ thin-film deposited at 3 mTorr showed the best gas-tightness and cell performance. At 500 °C, 1.043 V of OCV and a maximum power density of 1593 mW/cm2 were observed. Then, X-ray diffraction was used to calculate the residual stress of the YSZ films. As a result, it was confirmed that the gas-tight film showed compressive residual stress. Through this study, we were successful in developing a room-temperature YSZ electrolyte fabrication process with excellent gas-tightness and performance. It was also proven that there is a strong relationship between the gas-tightness and residual stress. This study is expected to contribute to cost reductions and the mass production of solid oxide fuel cells.

APA, Harvard, Vancouver, ISO, and other styles

13

An, Junjie, Guang Li, Gang Liu, Cheng Xue, Dingge Hou, Shaolong Wang, Zhendi Wang, and Bin Li. "Research progress of tunnel air-tight concrete." E3S Web of Conferences 358 (2022): 02043. http://dx.doi.org/10.1051/e3sconf/202235802043.

Full text

Abstract:

With the quick development of transportation network construction, the tunnel construction has been an important part. During the tunnel construction process, especially in the gas zone, gas leaking has been a common problem. For avoiding gas leakage, it is necessary to enhance the air-tightness of the tunnel concrete, air-tight concrete is a kind of concrete with excellent air tightness performance. In this paper, we introduced the research progress of tunnel air-tight concrete, including the effect of mix ratio, composition on the air-tight performance of tunnel concrete and corresponding characterization methods.

APA, Harvard, Vancouver, ISO, and other styles

14

Wu, Xiaowei, and Zhaoxi Tang. "Influence of Silica Fume on the Performance of Moderately Weathered Phonolite Concrete." E3S Web of Conferences 293 (2021): 02032. http://dx.doi.org/10.1051/e3sconf/202129302032.

Full text

Abstract:

The effect of silica fume on the performance, mechanical properties, durability and air tightness of airtight concrete was studied. The results showed that with the increase of silica fume content, the concrete performance will decrease, the compressive strength of airtight concrete will increase first, and reach the highest when the silica fume content was 8%, and then it will decrease gradually. With the increase of silica fume content, the corrosion resistance coefficient of concrete increased gradually, then decreased. The permeability coefficient of concrete decreases with the increase of silica fume content, and the air tightness of concrete was improved obviously; In the project, it was advisable to use silica fume to prepare airtight concrete, and the amount of silica fume should be controlled at 4% - 8%.

APA, Harvard, Vancouver, ISO, and other styles

15

Brojan, Larisa, Ben Weil, and Peggi L. Clouston. "AIR TIGHTNESS OF STRAW BALE CONSTRUCTION." Journal of Green Building 10, no. 1 (April 2015): 99–113. http://dx.doi.org/10.3992/jgb.10.1.99.

Full text

Abstract:

Straw bale construction offers a renewable, sustainable and proven alternative to mainstream building methods; still, little is known about its airflow characteristics. To this end, the intent of this paper is to evaluate airtightness of fully constructed and plastered straw bale walls as well as individual plain straw bales. The first experiment entailed measuring the influence of straw bale orientation on airflow characteristics with the finding that straw bale considered alone has poor air flow-retarding characteristics and that plaster is the primary air barrier. A second experiment involved thirty plastered straw bale specimens using three different plaster types. From this experiment, a crack grading system was developed and is herein proposed as a tool to evaluate plaster performance as an air barrier. A third experiment validated the crack grade system through application on four fully constructed straw bale walls. Practical use of the crack grading system was demonstrated on a case study straw bale house in Radomlje, Slovenia, where the predicted air tightness results were validated through comparison to results of blower door tests.

APA, Harvard, Vancouver, ISO, and other styles

16

E, Khuluqo I., and Tenkahary C. M. "The Influence of Managerial Ability of School Principals and The Climate of School Organizations on Teacher Performance During The Covid-19 Pandemic." Journal of Education Technology 5, no. 1 (April 8, 2021): 145. http://dx.doi.org/10.23887/jet.v5i1.33629.

Full text

Abstract:

The role of school principals is very important in optimizing teacher performance during the Covid-19 pandemic. In addition, a conducive school organizational climate is able to provide solutions to teacher performance problems that arise during the Covid-19 pandemic. This study aims to analyze the effect of Principal Managerial Ability and School Organizational Climate on Teacher Performance During the Covid-19 Pandemic. This type of research is quantitative research. The research method used is a quantitative method. The population in this study amounted to 184. The sample in this study was 126 teachers. The technique used to collect data is interview and observation. The instrument used to collect data is a questionnaire. The results showed that the principal's managerial ability had an effect on teacher performance as indicated by the Fcount 92,102 (p <0.05) and had a strong tightness based on the correlation coefficient value of 0.653. Furthermore, the school organizational climate affects teacher performance as indicated by the Fcount 126,784 (p <0.05) and has a strong tightness based on the correlation coefficient of 0.711. In addition, the principal's managerial ability and school organizational climate simultaneously affect teacher performance based on the Fcount 75.497 (p <0.05) and has a strong tightness based on the R value of 0.742. It can be concluded that the principal's managerial ability and the school's organizational climate simultaneously affect teacher performance during the Covid-19 pandemic.

APA, Harvard, Vancouver, ISO, and other styles

17

Tuns, I., D. N. Isopescu, F. L. Tamas, and I. Boian. "The influence of waterproofing additives introduced into the mass of fresh concrete on the on the durability feature of the hardened concrete." IOP Conference Series: Materials Science and Engineering 789, no. 1 (March 1, 2020): 012059. http://dx.doi.org/10.1088/1757-899x/789/1/012059.

Full text

Abstract:

Abstract The constructions with fluid retention and storage in general, between which the water holds a significant weight, are permanently exposed of physical and mechanical actions of deposited agent, with the continuous manifestation of the exfiltration tendency, herby the requirement of performance at tightness becomes essential. If the constructions that fulfill this role are realized of reinforced concrete, the tightness at fluid in general and at water in particular of the elements which compose the storage space is insured in a significant proportion by the waterproofing qualities of the structural concrete put in place. When the process of waterproofing concrete is clean and environmentally friendly and leads to improvement of initial physical-mechanical characteristics, represents an essential element in the combined approach of the performance requirements regarding the tightness and resistance condition. In this paper is presented a research study concerning the positive influence of waterproofing additive “Penetron” introduced into the fresh concrete mass used to realization of structural elements, with the role of storage and treatment of waste water, to mechanical characteristics of concrete after hardening.

APA, Harvard, Vancouver, ISO, and other styles

18

Devkota, Prakash, and Joonam Park. "Air-tightness Performance Evaluation of Different Types of Concrete Tube Structures." Journal of the Korean Society for Railway 24, no. 9 (September 30, 2021): 810–17. http://dx.doi.org/10.7782/jksr.2021.24.9.810.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Li, Chengguang, and Michele J. Gelfand. "The influence of cultural tightness-looseness on cross-border acquisition performance." Journal of Economic Behavior & Organization 195 (March 2022): 1–15. http://dx.doi.org/10.1016/j.jebo.2022.01.004.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Üstün, Ferda, and Kemal Can Kılıç. "The effects of tightness-looseness in organizational culture on corporate entrepreneurship and firm performance: A regional study in Turkey." Journal of Human Sciences 14, no. 4 (November 28, 2017): 3866. http://dx.doi.org/10.14687/jhs.v14i4.4933.

Full text

Abstract:

In this study, the tightness-looseness dimension, suggested as a cultural dimension of community was examined at organizational level. Introducing the tightness-looseness dimension to the literature, and identifying the effects of the dimension on corporate entrepreneurship activities and firm performance, which poses great importance for organizations, were the main purposes of the study. In the study, the correlations between dependent and independent variables were examined through the hypotheses suggested, and the consistency level of the model was analyzed through the structural equation modeling. It was concluded from the study that there was a significant positive correlation between the tightness-looseness level and corporate entrepreneurship and firm performance. Coefficients of corporate entrepreneurship, proactivity, innovational orientation, and coefficients of firm performance, and coefficients concerning the profit, growth, and customer satisfaction seem to be statistically significant. Accordingly, the higher (or lower) the level of looseness is, the higher (or lower) the level of corporate entrepreneurship and firm performance will be. The validity of the model on the target sample has been discussed considering the compliance indices of the model proposed in the study on Turkey's leading industrial enterprises. As the results of the analysis of the constructed structural equation model gave the values of good and acceptance level goodness of fit (RMSEA <0.05, GFI and CFI> 0.95 and AGFI> 0.90), the model was found to be acceptable.

APA, Harvard, Vancouver, ISO, and other styles

21

Zhang, Yan, and He Hui Wang. "Emergency Stop and Drive Analysis of Bolted Flange Joints." Applied Mechanics and Materials 799-800 (October 2015): 585–88. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.585.

Full text

Abstract:

The strength and tightness of flange joints will be weaker due to the temperature fluctuations. There exists no mature calculation procedure that can accounts for the temperature fluctuations’ effect on the performance of flanged joint. Based on the finite element simulation of a flanged joint under emergency stop and drive condition using ANSYS, the strength integrity and sealing performance of it are evaluated according to code JB4732-2005. The results show that stress of every component increases after experiencing an emergency stop and drive, flange deflection is more serious, resulting in integrity and tightness failure and can’t meet the sealing requirements. Repeatedly stop and drive will lead to discontinuity and alternating loads for the flanged joints, which will increase the leakage trend.

APA, Harvard, Vancouver, ISO, and other styles

22

Liu, Dianbo, Alex Lamb, Xu Ji, Pascal Junior Tikeng Notsawo, Michael Mozer, Yoshua Bengio, and Kenji Kawaguchi. "Adaptive Discrete Communication Bottlenecks with Dynamic Vector Quantization for Heterogeneous Representational Coarseness." Proceedings of the AAAI Conference on Artificial Intelligence 37, no. 7 (June 26, 2023): 8825–33. http://dx.doi.org/10.1609/aaai.v37i7.26061.

Full text

Abstract:

Vector Quantization (VQ) is a method for discretizing latent representations and has become a major part of the deep learning toolkit. It has been theoretically and empirically shown that discretization of representations leads to improved generalization, including in reinforcement learning where discretization can be used to bottleneck multi-agent communication to promote agent specialization and robustness. The discretization tightness of most VQ-based methods is defined by the number of discrete codes in the representation vector and the codebook size, which are fixed as hyperparameters. In this work, we propose learning to dynamically select discretization tightness conditioned on inputs, based on the hypothesis that data naturally contains variations in complexity that call for different levels of representational coarseness which is observed in many heterogeneous data sets. We show that dynamically varying tightness in communication bottlenecks can improve model performance on visual reasoning and reinforcement learning tasks with heterogeneity in representations.

APA, Harvard, Vancouver, ISO, and other styles

23

Li, Chengguang, and Michele Joy Gelfand. "Culture's Price Tag in Cross-Border Acquisitions: How Tightness- Looseness Affects Performance." Academy of Management Proceedings 2019, no. 1 (August 1, 2019): 10027. http://dx.doi.org/10.5465/ambpp.2019.10027abstract.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Shutters, Shade T., Holger Seibert, Bastian Alm, and Keith Waters. "Industry Interconnectedness and Regional Economic Growth in Germany." Urban Science 6, no. 1 (December 21, 2021): 1. http://dx.doi.org/10.3390/urbansci6010001.

Full text

Abstract:

Urban systems, and regions more generally, are the epicenters of many of today’s social issues. Yet they are also the global drivers of technological innovation, and thus it is critical that we understand their vulnerabilities and what makes them resilient to different types of shocks. We take regions to be systems composed of internal networks of interdependent components. As the connectedness of those networks increases, it allows information and resources to move more rapidly within a region. Yet, it also increases the speed and efficiency at which the effects of shocks cascade through the system. Here we analyzed regional networks of interdependent industries and how their structures relate to a region’s vulnerability to shocks. Methodologically, we utilized a metric of economic connectedness called tightness which quantifies a region’s internal connectedness relative to other regions. We calculated tightness for German regions during the Great Recession, comparing it to each region’s economic performance during the shock (2007–2009) and during recovery (2009–2011). We find that tightness is negatively correlated with changes in economic performance during the shock but positively during recovery. This suggests that regional economic planners face a tradeoff between being more productive or being more vulnerable to the next economic shock.

APA, Harvard, Vancouver, ISO, and other styles

25

Cao, Cong, Ning Li, and Li Liu. "Do national cultures matter in the containment of COVID-19?" International Journal of Sociology and Social Policy 40, no. 9/10 (October 1, 2020): 939–61. http://dx.doi.org/10.1108/ijssp-07-2020-0334.

Full text

Abstract:

PurposeThis paper empirically investigates how cultural variations in individualism and tightness affected the containment of COVID-19 using data from 54 nations during a 30-day period of government intervention.Design/methodology/approachThe authors utilized the hierarchical regression approach to check the effects of three cultural variables – the individualism measure, taken from Hofstede’s six-dimension national culture index, and the measure of cultural tightness, based on the three tightness–looseness indexes calculated by Irem Uz (2015) and their interaction – on the changes in the prevalence rate (ΔPR) and crude mortality rate (ΔCMR) and case fatality rate (CFR) while controlling for the stringency of government responses to COVID-19, median age and population density.FindingsSignificant relationships were found between cultural variables and national performance in slowing the spread of the coronavirus, measured by ΔPR, ΔCMR and CFR. After controlling for the stringency of government responses, median age and population density, the authors found that cultural tightness and individualism as well as their interactions remain to be pivotal. Loose and individualistic cultures led to faster increases in PR and CMR and higher CFR. A four-quadrant conceptual framework is developed to categorize and discuss the national differences.Originality/valueThe paper integrated two constructs – cultural tightness–looseness and individualism–collectivism – to form a theoretical lens to guide the authors’ analyses while using the real-time COVID-19 data as a natural experiment for theorizing and testing. This study’s findings have significant policy implications in government responses, strategic planning, cultural adaptability and policy implementations for the world’s continuous battle against the pandemic.

APA, Harvard, Vancouver, ISO, and other styles

26

Arifin, Fransiscus, Timothy Sullivan, and Rajesh Dhakal. "Experimental investigation into the seismic fragility of a commercial glazing system." Bulletin of the New Zealand Society for Earthquake Engineering 53, no. 3 (September 1, 2020): 144–49. http://dx.doi.org/10.5459/bnzsee.53.3.144-149.

Full text

Abstract:

Good seismic performance of glazing systems is essential to maintaining building functionality and limiting repair costs in a post-earthquake scenario. This paper reports on experimental research into the seismic performance of a standard commercial glazing system used in New Zealand. The focus of the research is to provide information not only on the life-safety performance of glazing but also on the serviceability of glazing systems, considering post-earthquake weather-tightness. This paper first describes the experimental testing set-up developed at the University of Canterbury to achieve this, then details the damage observed and finally, fragility functions for different damage states are reported. Leakage of the glazing is seen to initiate at a median storey drift demand of only 0.35%, whereas glass breakage did not occur until a median drift storey demand of 5.0%. The results obtained from this research demonstrate that the life-safety risk posed by modern commercial glazing in earthquakes will typically be low but the serviceability performance, and in particular weather-tightness post-earthquake, should be improved.

APA, Harvard, Vancouver, ISO, and other styles

27

Lv, Xiang Kui, Jun Li, Xiao Ming Huang, and Guo Liang Xu. "Application of Orthogonal Experimental Method in the Sealing Design of a Bolted Flange Connections." Applied Mechanics and Materials 723 (January 2015): 104–9. http://dx.doi.org/10.4028/www.scientific.net/amm.723.104.

Full text

Abstract:

The paper aims to provide a theoretical method of multi-parameter optimization collocation for sealing structure design. Based on the tightness analysis method, the paper analyzed the effects of several major influence factors on the maximal gasket contact stress. Some sensitive parameters were chosen according to the tightness analysis results. Orthogonal experiment method was applied in the current work to find the optimum combination of parameters which will contribute to a better sealing performance of the connections. The theoretical way proposed in this paper can effectively shorten the design period and is helpful to improve the quality of the design and reduce the design cost.

APA, Harvard, Vancouver, ISO, and other styles

28

Damian, Lia-Raluca, Ramona Dumitrescu, Daniela Jumanca, Ruxandra Sava Rosianu, Anamaria Matichescu, Octavia Balean, Angela Podariu, Sebastian-Aurelian Stefaniga, and Atena Galuscan. "Clinical Study Regarding the Property of Composite Resin, Sealants, using VISTACAM iX." Materiale Plastice 56, no. 1 (March 30, 2019): 138–43. http://dx.doi.org/10.37358/mp.19.1.5139.

Full text

Abstract:

Purpose of the articleto carry out an epidemiological study on the use of sealing as a method of preventing dental caries and to assess the tightness and integrity over time of composite resins used to seal pits and fissures using the VistaCam iX intraoral fluorescence camera. Based on the premise that dentists do not have enough confidence in sealing pits and fissures as a method of preventing dental caries, we assessed if sealing is used in current practice as a prevention metod of tooth decay, and we measured, with high performance intraoral camera such as the VistaCam iX device, the tightness and integrity of composite resin seals.

APA, Harvard, Vancouver, ISO, and other styles

29

Sülar, Vildan, and Eren Oner. "Impact of Repeated Home Laundering on the Cyclic Deformation Performance of Elastane Knitted Sportswear Fabrics." Fibres and Textiles in Eastern Europe 27, no. 1(133) (February 28, 2019): 91–99. http://dx.doi.org/10.5604/01.3001.0012.7513.

Full text

Abstract:

After washing cycles, textiles having minimum deformation, maximum dimensional stability and the same performance of an unused product are major expectations of customers. This study examined the effects of washing cycles on the cyclic deformation of elastane knitted fabrics in detail. 12 knitted fabrics with two different linear densities of viscose yarn and three different polyamide/elastane gimped yarn of two different tightness levels (normal and tight) were used in the experiments. M&S P15A test method were used to evaluate the cyclic deformation of unwashed and washed fabrics (0, 5, 15 and 25 cycles) for four different recovery time periods (0 min, 2 min, 30 min and 24 h). Dimensional change, tightness factor and mass per unit area values were also examined in order to investigate the residual deformation of the fabrics after each washing stages. Consequently, it is determined that the fabrics having 21 tex viscose ground yarn and 78dtex20f elastane gimped yarn with higher setting show less residual extension (%). 5 and 15 washing cycles and a 30 min. recovery time are found significant for all repeated washings.

APA, Harvard, Vancouver, ISO, and other styles

30

Rana, Zaid Ashraf, Cheng Seong Khor, and Haslinda Zabiri. "Computational Experience with Piecewise Linear Relaxations for Petroleum Refinery Planning." Processes 9, no. 9 (September 9, 2021): 1624. http://dx.doi.org/10.3390/pr9091624.

Full text

Abstract:

Refinery planning optimization is a challenging problem as regards handling the nonconvex bilinearity, mainly due to pooling operations in processes such as crude oil distillation and product blending. This work investigated the performance of several representative piecewise linear (or piecewise affine) relaxation schemes (referred to as McCormick, bm, nf5, and nf6t) and de (which is a new approach proposed based on eigenvector decomposition) that mainly give rise to mixed-integer optimization programs to convexify a bilinear term using predetermined univariate partitioning for instances of uniform and non-uniform partition sizes. The computational results showed that applying these schemes improves the relaxation tightness compared to only applying convex and concave envelopes as estimators. Uniform partition sizes typically perform better in terms of relaxation solution quality and convergence behavior. It was also seen that there is a limit on the number of partitions that contribute to relaxation tightness, which does not necessarily correspond to a larger number of partitions, while a direct relationship between relaxation size and tightness does not always hold for non-uniform partition sizes.

APA, Harvard, Vancouver, ISO, and other styles

31

Song, Huiping, Chunhui Liu, Fangbin Xue, Xuhui Wen, and Fangqin Cheng. "Experimental Study on Coal Fly Ash-Based Gas-Sealing Coating Used for Coal Mine Roadway Walls." Coatings 10, no. 9 (September 6, 2020): 863. http://dx.doi.org/10.3390/coatings10090863.

Full text

Abstract:

Gas-sealing coatings on coal mine roadway walls can effectively repress gas emission and are of importance to the safe operation of coal mining. In this study, the performance of coal fly ash (CFA)-based gas-sealing coatings was investigated, including the aspects of drying time, air tightness, impermeability, flame retardancy and antistatic properties. The results show that coating No. 25 with 60 g ultrafine CFA and 50 g emulsion (curing at 22 °C) had the best air tightness, with a permeability coefficient of 2.95 × 10−13 cm2/(s·Pa). The data obtained through the self-developed air tightness test device agreed well with the detection results of the gas permeameter, thus verifying the accuracy and reliability of the device. The impermeability, flame retardancy and antistatic properties of coating No. 25 conformed the requirements of voluntary national standards GB/T 23445-2009 and coal industry standard MT113-1995, respectively. The CFA-based gas-sealing coating in the pilot test reduced the gas emission intensity by 40%–50%. It could have wide applications in coal mine roadway walls.

APA, Harvard, Vancouver, ISO, and other styles

32

Stano, Gianni, Luca Arleo, and Gianluca Percoco. "Additive Manufacturing for Soft Robotics: Design and Fabrication of Airtight, Monolithic Bending PneuNets with Embedded Air Connectors." Micromachines 11, no. 5 (May 9, 2020): 485. http://dx.doi.org/10.3390/mi11050485.

Full text

Abstract:

Air tightness is a challenging task for 3D-printed components, especially for fused filament fabrication (FFF), due to inherent issues, related to the layer-by-layer fabrication method. On the other hand, the capability of 3D print airtight cavities with complex shapes is very attractive for several emerging research fields, such as soft robotics. The present paper proposes a repeatable methodology to 3D print airtight soft actuators with embedded air connectors. The FFF process has been optimized to manufacture monolithic bending PneuNets (MBPs), an emerging class of soft robots. FFF has several advantages in soft robot fabrication: (i) it is a fully automated process which does not require manual tasks as for molding, (ii) it is one of the most ubiquitous and inexpensive (FFF 3D printers costs < $200) 3D-printing technologies, and (iii) more materials can be used in the same printing cycle which allows embedding of several elements in the soft robot body. Using commercial soft filaments and a dual-extruder 3D printer, at first, a novel air connector which can be easily embedded in each soft robot, made via FFF technology with a single printing cycle, has been fabricated and tested. This new embedded air connector (EAC) prevents air leaks at the interface between pneumatic pipe and soft robot and replaces the commercial air connections, often origin of leakages in soft robots. A subsequent experimental study using four different shapes of MBPs, each equipped with EAC, showed the way in which different design configurations can affect bending performance. By focusing on the best performing shape, among the tested ones, the authors studied the relationship between bending performance and air tightness, proving how the Design for Additive Manufacturing approach is essential for advanced applications involving FFF. In particular, the relationship between chamber wall thickness and printing parameters has been analyzed, the thickness of the walls has been studied from 1.6 to 1 mm while maintaining air tightness and improving the bending angle by 76.7% under a pressure of 4 bar. It emerged that the main printing parameter affecting chamber wall air tightness is the line width that, in conjunction with the wall thickness, can ensure air tightness of the soft actuator body.

APA, Harvard, Vancouver, ISO, and other styles

33

Li, Chenchen, and Chi Yue Chiu. "National Power Equality and Innovation Performance: The Moderating Role of Societal Tightness (WITHDRAWN)." Academy of Management Proceedings 2017, no. 1 (August 2017): 11127. http://dx.doi.org/10.5465/ambpp.2017.11127abstract.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Šadauskienė, Jolanta, Valdas Paukštys, Lina Šeduikytė, and Karolis Banionis. "Impact of Air Tightness on the Evaluation of Building Energy Performance in Lithuania." Energies 7, no. 8 (August 4, 2014): 4972–87. http://dx.doi.org/10.3390/en7084972.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Shekarchi, M., and G. Debicki. "Comportement thermohydrique d’une paroi en béton : influence du type de béton, influence du type de chargement." Canadian Journal of Civil Engineering 34, no. 10 (October 1, 2007): 1364–70. http://dx.doi.org/10.1139/l07-106.

Full text

Abstract:

Tests simulating “the accidental conditions” and the “test of heating,” without the contribution of humidity, have been carried out on test equipment that we designed and fabricated in the scope of this work. The tests have been carried out on laterally sealed and insulated cylindrical specimens of ordinary or high-performance concrete having a thickness of 1.3 m. Experimental results present temperature, pressure, and moisture distribution throughout the specimens and permit to characterize the hygrothermal behaviour of a concrete wall. The different aspects of the phenomena affecting a two-phase transfer (steam, water) in a porous medium are presented. Test results show that high-performance concrete exposed to an increase in temperature presents a particular hygrothermal behaviour, because of its microstructure, that is put into evidence, notably while looking at the role of the silica fume. The migration of water is not as rapid in high-performance concrete as in ordinary concrete, which is favourable for tightness. Numerical investigation consists of adapting a heat and mass transfer model, initially built for ordinary concrete, to the high-performance concrete used in this work.Key words: hygrothermal behavior, concrete wall, ordinary concrete, high-performance concrete, leak tightness, temperature distribution, pressure distribution, moisture distribution.

APA, Harvard, Vancouver, ISO, and other styles

36

Janoško, I., T. Polonec, and S. Lindák. "Performance parameters monitoring of the hydraulic system with bio-oil." Research in Agricultural Engineering 60, Special Issue (December 30, 2014): S37—S43. http://dx.doi.org/10.17221/32/2013-rae.

Full text

Abstract:

In environmental terms, hydraulic fluids used in the hydraulic system of municipal vehicles represent problems related to a potential leakage from the system into the environment and the subsequent contamination of groundwater and soil. More environment-friendly way is to use green hydraulic fluids that are biodegradable in accidents. This paper aims to investigate the possibilities of biodegradable oil application and its adaptation in the hydraulic systems of municipal vehicles by monitoring the impact of the bio-oil Mobil EAL 46 ESSO on the performance parameters as flow, efficiency, durability, etc. Hydraulic pump revolutions were measured using a non-contact sensor based on the principle of magnetic induction change. Method of tightness monitoring was used to achieve results for functionality and wear of the hydraulic system. During 600 h of the test period no significant deterioration of performance parameters was detected. Results are useful for companies involved in waste collection.

APA, Harvard, Vancouver, ISO, and other styles

37

Brynte, Lucas, Viktor Larsson, José Pedro Iglesias, Carl Olsson, and Fredrik Kahl. "On the Tightness of Semidefinite Relaxations for Rotation Estimation." Journal of Mathematical Imaging and Vision 64, no. 1 (October 7, 2021): 57–67. http://dx.doi.org/10.1007/s10851-021-01054-y.

Full text

Abstract:

AbstractWhy is it that semidefinite relaxations have been so successful in numerous applications in computer vision and robotics for solving non-convex optimization problems involving rotations? In studying the empirical performance, we note that there are few failure cases reported in the literature, in particular for estimation problems with a single rotation, motivating us to gain further theoretical understanding. A general framework based on tools from algebraic geometry is introduced for analyzing the power of semidefinite relaxations of problems with quadratic objective functions and rotational constraints. Applications include registration, hand–eye calibration, and rotation averaging. We characterize the extreme points and show that there exist failure cases for which the relaxation is not tight, even in the case of a single rotation. We also show that some problem classes are always tight given an appropriate parametrization. Our theoretical findings are accompanied with numerical simulations, providing further evidence and understanding of the results.

APA, Harvard, Vancouver, ISO, and other styles

38

Watanabe, Hiroyuki, Meguru Fujii, Masumi Yoshimoto, Hiroshi Abe, Naruaki Toda, Reiji Higashiyama, and Naonobu Takahira. "Pathogenic Factors Associated With Osgood-Schlatter Disease in Adolescent Male Soccer Players: A Prospective Cohort Study." Orthopaedic Journal of Sports Medicine 6, no. 8 (August 1, 2018): 232596711879219. http://dx.doi.org/10.1177/2325967118792192.

Full text

Abstract:

Background: A previous cross-sectional study reported that pathogenic factors associated with Osgood-Schlatter disease (OSD) in adolescent athletes include increased quadriceps muscle tightness, lower leg malalignment, and development of apophysitis in the tibial tuberosity. Purpose: To confirm these pathogenic factors associated with OSD in a longitudinal study with regard to physical function and performance. Study Design: Cohort study; Level of evidence, 2. Methods: In this study, 37 boys (mean age, 10.2 ± 0.4 years) were recruited from 2 soccer teams at an elementary school. This cohort study was conducted over an observation period of 1 year, with measurements recorded at baseline, followed by screening for OSD every 6 months. Variables evaluated at baseline included physical function (morphometry, joint flexibility, and lower extremity alignment), presence of Sever disease, and kicking motion. Results: Pathogenic factors associated with OSD in the support leg of adolescent male soccer players included height, weight, body mass index, quadriceps femoris muscle tightness in the kicking and support legs, and gastrocnemius muscle tightness, soleus muscle tightness, and medial longitudinal arch in the support leg. Additional factors included a diagnosis of Sever disease and distance from the lateral malleolus of the support leg’s fibula to the center of gravity during kicking. Conclusion: The onset of OSD was found to be affected by many factors, including developmental stage, physical attributes, and pre-existing apophysitis. In particular, a diagnosis of Sever disease and backward shifting of the center of gravity during kicking increased the risk of the subsequent onset of OSD, suggesting that these factors are very important as a possible focus for interventions.

APA, Harvard, Vancouver, ISO, and other styles

39

Andonov, Anton, Dimitar Stefanov, and Marin Kostov. "An Approach for Performance-Based Capacity Assessment of Prestressed Concrete Containment Vessels for Internal Accidents Application to VVER 1000 Containment Vessel." Journal of Disaster Research 5, no. 4 (August 1, 2010): 452–62. http://dx.doi.org/10.20965/jdr.2010.p0452.

Full text

Abstract:

A direct procedure is proposed for capacity assessment of prestressed concrete containment structures subjected to internal accident loads. The assessment procedure is based on graphical comparison between the structural capacity and the load intensity by plotting both parameters in the same “temperature gradient – overpressure” coordinate system. Furthermore, the capacity in terms of structural integrity and leak tightness is evaluated, corresponding to different limit states or performance levels. A new damage index is proposed in order to correlate the intensity of damages on the containment structure with the load intensity. The criteria for leak tightness and structural integrity are adopted for VVER-1000 containment structure. The ultimate pressure capacity, the failure mode and the capacity corresponding to different performance levels of the containment structure are assessed. The influence of the temperature load on the structure response is also studied. Conclusions are drawn on the VVER-1000 containment vessel overpressure capacity and its response to different design basis and severe accidents. The main failure mode and the critical zones of the structure are also determined.

APA, Harvard, Vancouver, ISO, and other styles

40

Nie, Wen, Duanyi Wang, Yangguang Sun, Wei Xu, and Xiaoquan Xiao. "Integrated Design of Structure and Material of Epoxy Asphalt Mixture Used in Steel Bridge Deck Pavement." Buildings 12, no. 1 (December 23, 2021): 9. http://dx.doi.org/10.3390/buildings12010009.

Full text

Abstract:

To comprehensively investigate the integrated structural and material design of the epoxy asphalt mixture used in steel bridge deck pavement, the following works have been conducted: 1. The strain level of steel bridge deck pavement was calculated; 2. The ultimate strain level of fatigue endurance for epoxy asphalt concrete was measured; 3. The effect of water tightness of epoxy asphalt mixture on the bonding performance of steel plate interface was tested. 4. For better performance evaluation, quantitative analysis of the anti-skid performance of epoxy asphalt mixture was carried out by testing the structure depth using a laser texture tester. Results show the following findings: 1. The fatigue endurance limit strain level of epoxy asphalt mixture (600 με) was higher than that of the steel bridge deck pavement (<300 με), indicating that the use of epoxy asphalt concrete has better flexibility and can achieve a longer service life in theory; 2. The epoxy asphalt concrete has significant water tightness to protect the steel plate interface from corrosion and ensure good bonding performance; 3. The porosity of epoxy asphalt mixture used in steel bridge deck paving should be controlled within 3%; 4. In terms of anti-skid performance of bridge deck pavement, the FAC-10 graded epoxy asphalt mixture is recommended when compared with EA-10C.

APA, Harvard, Vancouver, ISO, and other styles

41

Alexopoulos, T., E. N. Gazis, S. Maltezos, G. Koutelieris, S. Koutsoupi, P. Tzanis, S. Tzanos, and S. Vlachos. "Methods used for Gas Tightness Test and percent Oxygen Monitoring of the NSW Micromegas Detectors of LHC-ATLAS Experiment." Journal of Physics: Conference Series 2105, no. 1 (November 1, 2021): 012022. http://dx.doi.org/10.1088/1742-6596/2105/1/012022.

Full text

Abstract:

Abstract In the frame of the LHC-ATLAS Upgrade of phase I, the New Small Wheel detector system is under integration and commissioning at CERN Laboratories. One of the detector type, the Micromegas detectors, during their integration are tested in several stages for gas tightness validation. In particular, the novel method we are using for the gas tightness test, that we called “Flow Rate Loss”, has been realized in several semi-automatic fixed, portable and stand-alone setups for testing either the Micromegas Quads or the final Double Wedges. The obtained measurements up-to-date are presented as well as their obtained statistical distribution. Additionally, during the performance evaluation of the detectors, a percent oxygen monitoring is also performed in 24-hour base. The methods and techniques we developed and used are presented analytically in this work.

APA, Harvard, Vancouver, ISO, and other styles

42

Cai, Yun Tao, and Bo Qiang Shi. "Preparation Optimization Design of Tennis Ball Adhesive Formula." Applied Mechanics and Materials 401-403 (September 2013): 933–37. http://dx.doi.org/10.4028/www.scientific.net/amm.401-403.933.

Full text

Abstract:

The tennis ball adhesive formula is optimized by studying the impact of reinforcing system, tackifier, vulcanization system and solvent on the performance of NR-based tennis ball adhesive. The optimizing formula of rubber is: NR 100, Carbon Black N220 30, ZnO 8.3, Stearic Acid 2.2, Phenolic Tackifying Resin 3, Sulfur 3, Accelerator D0.5.The adhesive made through such optimizing formula shows good performance and the finished tennis ball has excellent adhesion and air tightness, satisfying the design requirements.

APA, Harvard, Vancouver, ISO, and other styles

43

Yang, Xu Dong, Xiao Hui Peng, Hong Hao Xu, and Xiong Yan. "Study on the Electromagnetic Shielding Performance of Wool/Stainless Steel Wire Worsted Fabric." Advanced Materials Research 821-822 (September 2013): 894–900. http://dx.doi.org/10.4028/www.scientific.net/amr.821-822.894.

Full text

Abstract:

Electromagnetic (EM) shielding effectiveness of fifteen woven fabrics which use different yarns as raw materials were evaluated and compared in this paper. Test samples were obtained through the change of yarn structure, the content of stainless steel filaments and process parameters. Fabric electromagnetic shielding effectiveness (SE) was analyzed in terms of the content of stainless steel filaments,fabric density and fabric tightness .The mechanism of electromagnetic shielding of worsted fabric with stainless steel filaments was further studied at different frequencies. The result has certain directive significance on developing high-performance woolen fabrics against electromagnetic radiation.

APA, Harvard, Vancouver, ISO, and other styles

44

Gu, Ling Ya, Fu Zhong Zhang, Xiao Fang Wang, and Xiao Lu Li. "Effect of Performance of Offset Paper on Ink Transfer." Applied Mechanics and Materials 731 (January 2015): 466–70. http://dx.doi.org/10.4028/www.scientific.net/amm.731.466.

Full text

Abstract:

In order to improve the printing quality, 10 kinds of different manufacturers, different gram weight offset paper are used in this title, measure the quantitative, thickness, gloss, K&N values, and roughness of those paper. Print papers through IGTAIC2-5, calculate the ink transfer rate and transfer parameters. Using SPSS to analysis relationship between the performance of paper and ink transfer rate, transfer parameter b, k, f ' by using mathematical methods. The research results show that the performance of the paper affect ink transfer rate and transfer parameter b, k, f '; The tightness, roughness ,glossiness and K&N value have notable effect on the ink transfer rate and transfer parameter k; transfer parameter b, f ' has no remarkable influence.

APA, Harvard, Vancouver, ISO, and other styles

45

Tacikowski, Michał, Janusz Kamiński, Krzysztof Rożniatowski, Marcin Pisarek, Rafał Jakieła, Paweł Marchlewski, and Tadeusz Wierzchoń. "Improving the Properties of Composite Titanium Nitride Layers on the AZ91D Magnesium Alloy Using Hydrothermal Treatment." Materials 14, no. 19 (October 8, 2021): 5903. http://dx.doi.org/10.3390/ma14195903.

Full text

Abstract:

Coating magnesium alloys with nitride surface layers is a prospective way of improving their intrinsically poor surface properties; in particular, their tribological and corrosion resistance. These layers are usually produced using PVD methods using magnetron sputtering or arc evaporation. Even though the thus-produced layers significantly increase the wear resistance of the alloys, their effects on corrosion resistance are unsatisfactory because of the poor tightness, characteristic of PVD-produced products. Tightness acquires crucial significance when the substrate is a highly-active magnesium alloy, hence our idea to tighten the layers by subjecting them to a post-deposition chemical-hydrothermal-type treatment. This paper presents the results of our experiments with a new hybrid surface engineering method, using a final tightening pressure hydrothermal gas treatment in overheated steam of the composite titanium nitride layers PVD, produced on AZ91D magnesium alloy. The proposed method resulted in an outstanding improvement of the performance properties, in particular resistance to corrosion and wear, yielding values that exceed those exhibited by commercially anodized alloys and austenitic stainless 316L steel. The developed hybrid method produces new, high-performance corrosion and wear resistant, lightweight magnesium base materials, suitable for heavy duty applications.

APA, Harvard, Vancouver, ISO, and other styles

46

Wang, He Hui, and Yan Zhang. "Creep Analysis of Combined Bolted Flange Joints under High Temperature." Applied Mechanics and Materials 624 (August 2014): 187–92. http://dx.doi.org/10.4028/www.scientific.net/amm.624.187.

Full text

Abstract:

The tightness of bolted flange joints will weaken due to the loss of bolt load as a result of creep under high temperature. There exists no mature calculation procedure that can accounts for creep. Based on the finite element simulation of a combined flanged joint under four various conditions, the strength integrity and sealing performance of it are evaluated according to the code JB4732-2005. The results show that the integrity and tightness of the combined flanged joint under pre-loading condition, pressure condition and operating condition (except local film stress) meet requirements. However, more than 50% of the bolt load relaxation is found due to creep, part of the gasket residual stress is lower than the required minimum sealing pressure. It can lead to leakage. Bigger bolt pre-tightening force, materials with good creep relaxation resistance and hot-tighting method are recommended to reduce the influence of creep.

APA, Harvard, Vancouver, ISO, and other styles

47

Hegishte, Atharva S., and Neeraj Kumar. "Effect of proprioceptive neuromuscular facilitation and dynamic stretching on flexibility, agility, and balance in hamstring tightness among collegiate level badminton players." International Journal of Research in Medical Sciences 11, no. 5 (April 29, 2023): 1758–63. http://dx.doi.org/10.18203/2320-6012.ijrms20231350.

Full text

Abstract:

Background: The development of muscular damage is typically attributed to intrinsic factors, such as muscle tension. Additionally, it has been demonstrated that muscular stiffness is the primary cause of the risk of pathological disorders of the knee and spine. Hamstring tightness leads to high risk of recurrent injury, decreases the performance in athletes, lead to post-exercise soreness and decreases coordination among athletes. Objectives of current study were to find out the effects of PNF and dynamic stretching on flexibility, balance, and agility among collegiate level badminton players having hamstring tightness. Methods: 110 participants were screened and 68 participants were recruited according to the selection criteria and were randomly allocated to Group A (PNF stretching) (N=34) and Group B (Dynamic Stretching) (N=34). The exercise program underwent training for 30 min, 3 times per week for 4 weeks. Results: Group A and Group B demonstrated significant improvement in Flexibility, Balance, and Agility (p<0.0001). Whereas, no significant difference was seen when intergroup comparison was done (p>0.005). Conclusions: The study concludes that there is significant improvement in the Flexibility, Balance, and Agility after implication of 4 weeks of PNF and Dynamic Stretching in Collegiate Level Badminton players having Hamstring tightness. This evidence substantiates that these exercises do recruit the Hamstring muscles and provides further insight into the role of the Hamstring muscles to keep the body flexible.

APA, Harvard, Vancouver, ISO, and other styles

48

Kim, Kyoung Sang, Yu Min Kim, Gyeong Seok Choi, and Jae Sik Kang. "Present Glazing Classification under the Energy Efficiency Labeling Program of Window System in Korea, South." Applied Mechanics and Materials 525 (February 2014): 435–38. http://dx.doi.org/10.4028/www.scientific.net/amm.525.435.

Full text

Abstract:

In order to prevent the large amount of energy use loss on the window system including the problematic condensation, poor indoor comfort, and the durability problem on the construction materials within the building enclosure system, the coverage for the high performance sustainable window system should be distributed excessively and encourage the industries willingly within any relevant industrial technologies. In this study, hence it is evaluated the performance distribution of the window system designing for the energy efficiency through the thermal and air-tightness performance evaluation based on the more than seven hundred sixty certified products in the Energy Efficiency Labeling Program.

APA, Harvard, Vancouver, ISO, and other styles

49

Arun, Korhan, Cem Şen, and Olcay Okun. "How does Leadership Effectiveness related to the Context? Paternalistic Leadership on non-financial Performance within a cultural Tightness- Looseness Model?" Journal of East European Management Studies 25, no. 3 (2020): 503–29. http://dx.doi.org/10.5771/0949-6181-2020-3-503.

Full text

Abstract:

Current emphasis in culture research focuses on how leaders might change the culture to improve organizational performance. However, how culture affects organizational performance under active leadership relations research has resulted in conceptual ambiguities, as well as contradictory empirical findings. We argue that organizational culture moderates the effectiveness of leadership on organizational performance. We used an ethical approach to generalize paternalistic leadership in moderating Turkish organizational culture. The results indicate that paternalistic leadership functions are divided into two dimensions: family relationships and non-work life involvement, and the overall effects of paternalistic leadership on non-financial performance are unconnected to organizational culture, namely cultural tightness-looseness (CTL).

APA, Harvard, Vancouver, ISO, and other styles

50

Czinkota, Michael R. "Executive Insights: A National Export Assistance Policy for New and Growing Businesses." Journal of International Marketing 2, no. 1 (March 1994): 91–101. http://dx.doi.org/10.1177/1069031x9400200106.

Full text

Abstract:

This article is based on a speech delivered by the author to the National Economic Council in Washington, D.C. The White House-based council is charged with strengthening the competitive performance of U.S. firms. The author highlights the need for clarity of purpose, tightness of focus, coordination of approaches, emphasis on strengths, targeting of crucial factors, and boldness of vision in shaping a new export assistance policy.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Tightness of Performance'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles