• Korean Management Science Review
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• v.29 no.1
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• pp.101-114
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• 2012

The demand for naval spare parts is intermittent and erratic. This feature, referred to as non-normal demand, makes forecasting difficult. Hierarchical forecasting using an aggregated time series can be more reliable to predict non-normal demand than direct forecasting. In practice the performance of hierarchical forecasting is not always superior to direct forecasting. The relative performance of the alternative forecasting methods depends on the demand features. This paper analyses the influence of the demand features on the performance of the alternative forecasting methods that use hierarchical and direct forecasting. Among various demand features variability, kurtosis, skewness and equipment groups are shown to significantly influence on the performance of the alternative forecasting methods.

• Fashion & Textile Research Journal
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• v.12 no.3
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• pp.372-380
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• 2010

The purpose of this study were to investigate a preference and demand performance of UV protective hat for outdoor sports activities. Data collected from 259 adults from survey were analyzed by frequence analysis, crosstabs, t-test, and ANOVA using SPSS 17.0. The results are as follows. A demand performanc of UV protective hats were a demand performance for designs, colors, fabrics, lightness, UV protection, and easy care. It showed that the respondents worn the hats for skin health and didn't wear for sun block. The demand performance of UV protective hat showed difference according to gender and age. The favorite type of UV protective hat was cap, and there was no difference between young and old age. Male preferred the cap styles, while female preferred the wide brim styles for UV protection. The preferred fiber contents of the respondents were cotton and functional fiber.

• The Research Journal of the Costume Culture
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• v.16 no.4
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• pp.681-695
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• 2008

This study was accomplished to investigate the preference of clothing materials and the clothing demand performance for underwear and everyday dress of atopic patients. As this study was the research study by a use of a questionnaire, the finally total 987 copies of the collected questionnaires were used to analyze the data. SPSS was used for the statistical analysis of data. To analyze the data, frequency analysis, percentage, $X^2$-test, reliability analysis, factor analysis, t-test, ANOVA and Duncan's multiple comparisons were used. The results obtained are as follows. In factor analysis for clothing materials and the demand performance which atopic patients favor, the preference factors for underwear materials were classified as pliability/a sense of weight, a sense of cold and warmth, tactility, and elasticity. Those for everyday wear were classified as pliability/surface roughness, a sense of cold and warmth, a sense of weight, and elasticity. And the demand performance factors for underwears were classified as thermophysiology, care convenience, and skin contact. Those for everyday wear were classified as comfortableness and care convenience. In the difference analysis for the preference and the demand performance, Both everyday wear and underwear showed a significant difference for the preference and the demand performance according to gender, age, income, education level, and occupation.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.18 no.3
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• pp.310-316
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• 2011

Purpose: In the present study, the difference in patients' nursing demands and nursing performance as perceived by the patients was examined. Methods: The participants were 272 patients on maintenance hemodialysis at five university hospitals. Nursing need and nursing performance were measured using the tool developed by Lee for this study. Results: The mean score for nursing demand was 3.35 points out of 4. The scores were higher for participants with middle school graduation or less, those not professing religion, and those whose medical insurance was of the medicaid type. The mean score for perceived nursing performance was 3.22 points out of 4. Nursing performance as perceived by hemodialysis patients was lower than nursing demand for 22 of 28 items. The item with the largest difference between nursing performance and nursing demand was 'Give a pain-free injection', followed by 'Explain about insurance benefits and supports' and 'Maintain quiet environment in the hemodialysis unit enabling rest during hemodialysis'. Conclusion: The results show that nursing performance as perceived by hemodialysis patients was lower than nursing demand. This result indicates a need to develop appropriate strategies to enhance nursing performance, especially for items that showed low nursing performance.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.2
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• pp.138-146
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• 2012

This paper studies the effect of information quality level and customer demand on performance measures in a supply chain. The information quality level compares 2 types, the information levels of a customer demand and a lead time. The customer demand process follows a general auto-correlated AR(1) process without seasonality. In the AR(1) process, ${\sigma}$ indicates the degree of demand fluctuation and ${\rho}$ means the trend of customer demand. ANOVA tests using a 5% significance level are performed in SPSS to examine significant performance changes among various cases.

• Steel and Composite Structures
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• v.37 no.2
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• pp.151-173
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• 2020

This paper aims to probabilistically evaluate performance of two types of I beam to box column (IBBC) connection. With the objective of considering the variability of seismic loading demand, statistical features of the inter-story drift ratio corresponding to the second, fifth and eleventh story of a 12-story steel special moment resisting frames are extracted through incremental dynamic analysis at global collapse state. Variability of geometrical variables and material strength are also taken into account. All of these random variables are exported as inputs to a probabilistic finite element model which simulates the connection. At the end, cumulative distribution functions of local seismic demand for each component of each connection are provided using histogram sampling. Through a parametric study on probabilistic local seismic demand, the influence of some geometrical random variables on the performance of IBBC connections is demonstrated. Furthermore, the probabilistic study revealed that IBBC connection with widened flange has a better performance than the un-widened flange. Also, a design procedure is proposed for WF connections to achieve a same connection performance in different stories.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.4
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• pp.225-233
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• 2010

In this paper, we try to improve the performance of the demand paging loader suggested to use the demand paging way that is not based on operating system. The demand paging switching strategy used in the existing operating system can know the recently used pages by running multi-processing. Then, based on it, some page switching strategies have been made for the recently used pages or the frequently demanded pages. However, the strategies based on operating system cannot be applied in single processing that is not based on operating system because any context switching never occur on the single processing. So, this paper is trying to suggest the demand paging switching strategies that can be applied in paging loader running in single process. In the Return-Prediction-Algorithm, we saw the improved performance in the program that the function call occurred frequently in a long distance. And then, in the Most-Frequently-Used-Page-Remain-Algorithm, we saw the improved performance in the program that the references frequently occurred for the particular pages. Likewise, it had an enormous effect on keeping the memory reduction performance by the demand paging and reducing the running time delay at the same time.

• Current Photovoltaic Research
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• v.5 no.3
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• pp.100-104
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• 2017

This paper analyzes the correlation between Net Benefit Test (NBT) and System marginal price (SMP), which has a significant impact on the allocation of demand response (DR) resources in resource scheduling and commitment (RSC) process, based on the performance data of the demand resource market which has been established in 2014. Demand resources compete with generation resources in the RSC process, and it is prescribed to use demand resources only when net benefit occurs. Analysis result shows that the larger the SMP than the Net Benefit Threshold Price (NBTP), the more the winning bid of demand response resource was. It is interpreted that the introduction of NBT in DR market is justified. The demand resource market has been steadily growing. It is required to expand the scope of resources up to the small-sized DR, and to expand the functionalities of demand resources not only in the current energy market but also in the reserve market in the future. In order for that, institutional improvements are required.

• Journal of the Earthquake Engineering Society of Korea
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• v.26 no.1
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• pp.31-38
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• 2022

Based on the nonlinear static analysis and the approximate seismic evaluation method adopted in "Guidelines for seismic performance evaluation for existing buildings, two methods to calculate strength demand for retrofitting individual structural walls in unreinforced masonry buildings are proposed." The displacement coefficient method to determine displacement demand from nonlinear static analysis results is used for the inverse calculation of overall strength demand required to reduce the displacement demand to a target value meeting the performance objective of the unreinforced masonry building to retrofit. A preliminary seismic evaluation method to screen out vulnerable buildings, of which detailed evaluation is necessary, is utilized to calculate overall strength demand without structural analysis based on the difference between the seismic demand and capacity. A system modification factor is introduced to the preliminary seismic evaluation method to reduce the strength demand considering inelastic deformation. The overall strength demand is distributed to the structural walls to retrofit based on the wall stiffness, including the remaining walls or otherwise. Four detached residential houses are modeled and analyzed using the nonlinear static and preliminary evaluation procedures to examine the proposed method.

• Research in Mathematical Education
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• v.16 no.3
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• pp.155-176
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• 2012

It is an important issue to explore classroom environments which are conducive to developing students' mathematical performance. This study explores the effects of different classroom environments (solution-demand and corresponding-time setting) on mathematical performances. Fourteen and eighteen prospective teachers were required to prove a task under different conditions respectively: a) Cognitive demand of multiple-solution corresponding time of three hours, and b) Cognitive demand of a right solution corresponding time of 20 minutes. We used SOLO as the assessment tool for mathematical performance from quality perspective. Significant differences were found in the quantity and quality of mathematical performance. The regular environment focusing on speed and accuracy were found to be directly linked to low levels of performance. The findings above provide implications to the cognitive benefits of multiple-solution demand and corresponding time setting.