• Title/Summary/Keyword: importance sampling (IS)

검색결과 314건 처리시간 1.41초

NUCLEAR DATA UNCERTAINTY AND SENSITIVITY ANALYSIS WITH XSUSA FOR FUEL ASSEMBLY DEPLETION CALCULATIONS

  • Zwermann, W.;Aures, A.;Gallner, L.;Hannstein, V.;Krzykacz-Hausmann, B.;Velkov, K.;Martinez, J.S.
    • Nuclear Engineering and Technology
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    • 제46권3호
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    • pp.343-352
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    • 2014
  • Uncertainty and sensitivity analyses with respect to nuclear data are performed with depletion calculations for BWR and PWR fuel assemblies specified in the framework of the UAM-LWR Benchmark Phase II. For this, the GRS sampling based tool XSUSA is employed together with the TRITON depletion sequences from the SCALE 6.1 code system. Uncertainties for multiplication factors and nuclide inventories are determined, as well as the main contributors to these result uncertainties by calculating importance indicators. The corresponding neutron transport calculations are performed with the deterministic discrete-ordinates code NEWT. In addition, the Monte Carlo code KENO in multi-group mode is used to demonstrate a method with which the number of neutron histories per calculation run can be substantially reduced as compared to that in a calculation for the nominal case without uncertainties, while uncertainties and sensitivities are obtained with almost the same accuracy.

Characteristics of Benthic Chlorophyll a and Sediment Properties in the Tidal Flats of Kwangyang Bay, Korea

  • Sin, Yong-Sik;Ryu, Sang-Ock;Song, Eun-Sook
    • ALGAE
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    • 제24권3호
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    • pp.149-161
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    • 2009
  • Characteristics of benthic microalgae and sediment properties were investigated for the intertidal flats of Kwangyang Bay, Korea. Sampling stations were selected every 100 m in the intertidal flats from land-side to open ocean at two different sampling sites. Samples were collected in June 2004, July, September, November, February and May 2005. Sediments properties were measured including temperature, water contents, sediment bulk density, nutrient concentrations in porewater. Chlorophyll a concentrations in surface sediment (0.5 cm) were measured and relationships between the chlorophyll a and various sediment properties were analyzed to identify major mechanisms regulating biomass of benthic microalgae in the intertidal flats using simple linear regression analysis. Sediment chlorophyll a concentrations were maximum during winter and minimum during warm seasons ranging from 4.4 mg $m^{-2}\;to\;81.2\;mg\;m^{-2}$. No clear spatial variations were observed for the sediment chlorophyll a in the study sites. Results from regression analysis suggested that benthic microalgae biomass was affected by sediment temperature and nutrients especially ammonium and silicate. Grazing effect was estimated using chlorophyll: pheopigments ratio, indirect indicator of grazing activity, and the positive correlation of the ratio and chlorophyll a implied that microalgae biomass is affected by grazing of zoobenthos although direct measurement of grazing activity is required to determine the importance of top-down controls in the benthic microalgae dynamics.

Development of Face Tracking System Using Skin Color and Facial Shape (얼굴의 색상과 모양정보를 이용한 조명 변화에 강인한 얼굴 추적 시스템 구현)

  • Lee, Hyung-Soo
    • The KIPS Transactions:PartB
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    • 제10B권6호
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    • pp.711-718
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    • 2003
  • In this paper, we propose a robust face tracking algorithm. It is based on Condensation algorithm [7] and uses skin color and facial shape as the observation measure. It is hard to integrate color weight and shape weight. So we propose the method that has two separate trackers which uses skin color and facial shape as the observation measure respectively. One tracker tracks skin colored region and the other tracks facial shape. We used importance sampling technique to limit sampling region of two trackers. For skin-colored region tracker, we propose an adaptive color model to avoid the effect of illumination change. The proposed face tracker performs robustly in clutter background and in the illumination changes.

Customer Satisfaction towards ATM Services: A Case of Vietcombank Vinh Long, Vietnam

  • Giao, Ha Nam Khanh
    • The Journal of Asian Finance, Economics and Business
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    • 제6권1호
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    • pp.141-148
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    • 2019
  • This research proposes a model of SERVQUAL scale calibration and uses the SERVPERF model to study the relationship between quality of ATM service and customer satisfaction. The research uses the combination of qualitative and quantitative methodology with the Cronbach's alpha reliability analysis, Exploratory Factor Analysis (EFA) method; Confirmation Factor Analysis (CFA) and Structural Equation Modeling (SEM) through SPSS and AMOS 20.0 data analysis software. The survey was conducted with 800 questionnaires with the convenient sampling method. The number of remaining sample for analysis was 779 responses of individual customers using ATM card services of Bank for Foreign Trade of Vietnam (Vietcombank) Vinh Long. The results show that the satisfaction of customers using ATM cards of Vietcombank Vinh Long is influenced by 4 factors with the order of importance as follows: (1) Price; (2) Network; (3) Reliability; (4) Empathy. Thereby, the author suggests some managerial implications to Vietcombank Vinh Long management to enhance the ATM service quality, then improve customer satisfaction. This research still has some limitations: (1) The study does not investigate other influencing factors, (2) The convenient sampling method has not been generalized well, (3) The research is only conducted for Vietcombank.

Combating Poverty in Malaysia: The Role of Zakat

  • ZULKIFLI, Muhammad Faris;TAHA, Roshaiza;AWANG, Rohila @ Norhamizah;MOHD NOR, Mohd Nazli;ALI, Azwadi
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.505-513
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    • 2021
  • Poverty is often referred to as a phenomenon of scarcity, inadequacy or instability of income. Besides, poverty can also cause health issues, exacerbate social problems, leading to isolation, discrimination and loss of a bright future. Lately, the role of zakat (the compulsory giving of a set proportion of one's wealth to charity) as a useful tool in combating poverty has been highlighted since zakat collected will be distributed specifically to the poor and needy groups. This paper seeks to assess the role of zakat in combating poverty among recipients. A questionnaire was distributed to 300 participants selected from the list of recipients who received assistance from Zakat institutions. A cluster random sampling has been utilized to select sampling from the target population. The data were analyzed using SPSS to provide descriptive analysis. Past evidence has shown how zakat has able to transform the recipient into a payer especially through education or business assistance. Proper management of zakat institution is seen as a powerful mechanism to facilitate community development and to strengthen the Muslim economy. Results show the importance of zakat in the effort to eradicate poverty and further able to improve the asnaf's quality of life.

The Effect of Supply Chain Management on Stakeholder Engagement: Empirical Evidence from Indonesia

  • DARMASTUTI, Ismi;GHOZALI, Imam;DJASTUTI, Indi
    • The Journal of Asian Finance, Economics and Business
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    • 제8권4호
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    • pp.1013-1020
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    • 2021
  • This study examines the role of dynamic socio-emotional capabilities to increase proactive stakeholder engagement in family businesses. The research sample includes all furniture enterprises scattered in Jepara Regency sub-districts as many as 3,945 companies. The sampling in this research is purposive; as many as 210 respondents, 181 could be used. The sampling unit is the owners and managers, considering that most company owners are also company managers. This study examines how learning and supply chain management in the family business can be integrated to enable a set of resources and capabilities provided by the family to be developed to build closer relationships with stakeholders. The findings showed the importance of a family business's supply chain management perspective in the relationship between dynamic socio-emotional capabilities to mediate organizational learning to proactive stakeholder engagement significantly. Based on this study's results, companies can build dynamic socio-emotional capabilities through organizational learning to increase proactive stakeholder engagement. Dynamic socio-emotional capabilities proved to play a role as a mediator for organizational learning by family companies for proactive stakeholder engagement.

The Relationship between Organizational Culture, Job Characteristics and Job Continuance among Police Officers (경찰공무원의 조직문화와 직무특성 및 직무지속의지의 관계)

  • Kim, Chan sun;Park, Young Man
    • Convergence Security Journal
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    • 제14권6_2호
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    • pp.63-72
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    • 2014
  • The purpose of this study is to investigate the relationship between organizational culture, job characteristics and job continuance will among police officers. This study targets the police officers dispatched in the Seoul metropolitan area in 2012, and it uses judgment sampling method to analyze 187 samples. This study conducted the statistical analysis, including frequency analysis, factor analysis, reliability analysis and multiple regression analysis, by using SPSS WIN 18.0. The result is as follows. First, the organizational culture among police officers has effects on job characteristics. That is, the feedback increases as the organizational culture becomes more mutual development- or agreement-oriented, or as it becomes more hierarchical; on the other hand, the job importance increases as more hierarchical and rational a culture becomes. Also, self-determination increases as an organization becomes more mutual development- or agreement-oriented. Second, the organizational culture among police officers has effects on the job continuance will. That is, the expected satisfaction increases but intentional insincerity decreases as the organizational culture becomes more mutual development- or agreement-oriented. Also, risk-perceiving behavior increases as an organizational culture becomes more hierarchical. Third, police officers' job characteristics have effects on the job continuance will. That is, the feedback and job importance increases the expected satisfaction while reducing functional diversity. The feedback also reduces the contraction factor. The job importance increases intentional insincerity while reducing functional diversity. The functional diversity not only increase alternative expectation but also increases risk-perceiving factors.

Purchase Decision Factors on Clothing in Internet Shopping Mall (인터넷 쇼핑몰에서의 의류제품 구매결정요인)

  • Ji, Hye-Kyung
    • Journal of the Korea Fashion and Costume Design Association
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    • 제14권2호
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    • pp.185-198
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    • 2012
  • This study aims to find out the influential factors and the relative power of these factors on the clothing purchase decision in internet shopping mall. For this purpose, this study surveyed 500 male and female consumers in their 20's~40's for empirical analysis who have ever purchased clothing through internet shopping malls. Respondents are selected using the convenience sampling through internet survey in August 2011. For statistical analysis descriptive statistics, reliability analysis, factor analysis and regression analysis are carried out using SPSS for Windows 12.0. The results are as follows. First, purchase decision is significantly affected by the expressional/physical properties of the product and product pictures. Second, purchase decision is significantly affected by the usefulness of shopping mall and the importance of purchase. Third, in consumer related factors, product value awareness, reliability of shopping mall, clothing involvement, psychological/economical perceived risks and age affect purchase decision. Fourth, in the regression analysis of the above significant variables on purchase decision, the order of power of these influential factors is expressional/physical properties of product, the importance of purchase, product picture, age and clothing involvement. The results of this study will help internet fashion enterprises to handle the variables of product, shopping mall, and consumer related for enhancing the purchase rate.

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Compulsive Buying of Fashion Goods Purchasers on TV Home Shopping Shows (TV 홈쇼핑에서의 패션제품 구매자의 강박 구매)

  • 박혜정
    • Journal of the Korean Society of Clothing and Textiles
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    • 제27권5호
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    • pp.588-599
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    • 2003
  • The convenience of TV home shopping is known to provoke compulsive buying, which is chronic and repetitive purchasing behavior that comes about as a response to negative events or feelings. The purpose of this study was to identify whether there is a difference in the degree of compulsive buying between the purchasers of fashion goods and the purchasers of non-fashion goods on TV home shopping shows and the determinants of compulsive buying and their relative importance. Utilizing the convenient sampling method, the sample of the study was composed of women aged over 20 living in the Seoul metropolitan area. Out of 380 distributed questionnaires, 270 useful questionnaires were returned. The data were analyzed using t-test, Pearson correlation, and multiple regression. The results indicated that TV home shoppers who purchased fashion goods showed higher degree of compulsive buying than those who purchased non-fashion goods and the determinants of compulsive buying are sample's age, mean age of the sample's children, credit usage, expenditure on fashion goods, frequency of purchase of fashion goods on TV home shopping shows, and promotional tools used by TV home shopping retailers. Regarding the relative importance of the determinants, credit usage was the most influential factor followed by expenditure on fashion goods and the length of exposure to TV home shopping shows.

Sample thread based real-time BRDF rendering (샘플 쓰레드 기반 실시간 BRDF 렌더링)

  • Kim, Soon-Hyun;Kyung, Min-Ho;Lee, Joo-Haeng
    • Journal of the Korea Computer Graphics Society
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    • 제16권3호
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    • pp.1-10
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    • 2010
  • In this paper, we propose a novel noiseless method of BRDF rendering on a GPU in real-time. Illumination at a surface point is formulated as an integral of BRDF producted with incident radiance over the hemi-sphere domain. The most popular method to compute the integral is the Monte Carlo method, which needs a large number of samples to achieve good image quality. But, it leads to increase of rendering time. Otherwise, a small number of sample points cause serious image noise. The main contribution of our work is a new importance sampling scheme producing a set of incoming ray samples varying continuously with respect to the eye ray. An incoming ray is importance-based sampled at different latitude angles of the eye ray, and then the ray samples are linearly connected to form a curve, called a thread. These threads give continuously moving incident rays for eye ray change, so they do not make image noise. Since even a small number of threads can achieve a plausible quality and also can be precomputed before rendering, they enable real-time BRDF rendering on the GPU.