• 한국주거학회:학술대회논문집
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• 한국주거학회 2003년도 정기총회 및 추계학술대회
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• pp.67-72
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• 2003

The present article evaluates a performance hall, which improves sound efficiency. In general, the sidewall of the music hall is plane circle. thus there happens a focus phenomenon. To overcome it. the music hall improves its sound efficiency by making its sidewall irregular. After measuring impulse response from the performance hall, evaluation indices on the temporal distribution of sound energy such as RT, EDT, D50, C80, RASTI and BR were obtained, and based on them, indoor acoustic characteristics and the generation of echoes were determined. According to the results, evaluation indices showed that the acoustic condition was satisfactory in general. This study is to provide fundamental data for acoustic design of music hall with round form by analyzing the room acoustic characteristics of music hall.

• 대한안전경영과학회지
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• 제16권4호
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• pp.417-426
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• 2014

Plant management have a greatest influence on the corporate variety of tasks such as production, quality, environment. So, various performance indices for plant management are operating. But plant management tasks can be carried out effectively, so that all of how to organize and efficiently manage indicators is lacking real condition In this paper, improved profitability, cost savings by applying the concept for the performance assessment, plant management services, such as the key indices for performance according to the objectives of the firm. Dashboard for plant management work using me to develop a system that manage.

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.165-172
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• 2003

This paper presents an operation scheme to enhance the power system security by applying FACTS on Power systems. Three main generic types of FACTS devices are suggested an illustrated. Flow congestions over lines have been solved by controlling active power of series-compensated FACTS devices and low voltages at buses have been solved by controlling reactive power of shunt-compensated FACTS devices. Especially, Especially, UPFC has been applied in both line congestion and low voltages. Two kinds of indices which indicate the power system security level related to line flow and bus voltage are utilized in this paper. They have been minimized to enhance the power system security level through the iterative method and the sensitivity vector of security index is derived to determine the direction to minimum. The proposed algorithm has been tested on the IEEE 57-bus system with FACTS devices in a normal condition and a line-faulted contingency.

• 대한기계학회논문집A
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• 제26권10호
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• pp.2060-2066
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• 2002

The closed-loop state and input observer is a pole-placement type observer and estimates unknown state and input variables simultaneously. Pole-placement type observers may have poor transient performance with respect to ill-conditioning factors such as unknown initial estimates, round-off error, etc. For the robust transient performance, the effects of these ill-conditioning factors must be minimized in designing observers. In this paper, the transient performance of the closed-loop state and input observer is investigated quantitatively by considering the error bounds due to ill-conditioning factors. The performance indices are selected from these error bounds and are related to the observer robustness with respect to the ill -conditioning factors. The closed-loop state and input observer with small performance indices is considered as a well-conditioned observer from the transient perspective.

• Structural Monitoring and Maintenance
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• 제9권4호
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• pp.373-388
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• 2022

A USW based diagnostic procedure is presented for estimating the depth of surface-breaking cracks. The diagnosis is demonstrated on seven lab-scale SFRC beam specimens, which are subjected to the CMOD controlled three-point bending test to create real bending cracks. Then, the recorded multiple ultrasonic signals are examined with the signal processing techniques, including wavelet transform and two-dimensional Fourier transform, to investigate the relationships between the crack depth and two diagnostic indices, namely the attenuation coefficient and dispersion index (DI). Finally, the reliabilities of these indices for depth estimation are verified with the visually measured crack depths as well as the crack features obtained with a digital image processing algorithm. It is found that the DI outperforms the attenuation coefficient in depth estimation, where this index displays good agreement with the visual inspection for 86% of the inspected specimens.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.199-204
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• 2012

This study was conducted to estimate climax index by eco-morphology for major 36 tree and sub-tree species in natural deciduous forests so as to interpret seral position of each species in the forest community. Fourteen eco-morphological characters which were considered to be associated with successional gradient in the forest were selected for the study. Four levels per character for each species were given on a standardized scale of increasing climax, and the index was computed by the proportion of the sum of total scores, expressed by percent values. With calculated mean value of 54.8 for all indices, Carpinus cordata had the highest index value of 90.5, and Populus davidiana recorded the lowest of 13.2. The most climax group, greater than 70 of the index, contained only 8 species, intermediate group, between 41 to 70 of the index, had 23 species, and the most pioneer group, less than 40 of the index comprised 5 species. The result has noticed that the large number of species would take advantage of most diverse resource and niche in the intermediate stage of the sere in the forest. By cluster analysis all 36 species were subjected to be classified into several species groups which had common similar eco-morphological characteristics. The indices were additionally plotted on the two dimensional graph to recognize the positions related to the light absorption factor and reproduction factor. The climax index of tree and sub-tree species developed by this study could be applied to understand the present status of successional stage on the basis of species composition by the method of summing up the indices. And comparison of forest successional stage among various forest communities could be done by summing up the climax indices of composed species in each community. However, this kind of applied methodology should be limited to the forest of similar species composition and site condition.

• 수산해양기술연구
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• 제23권2호
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• pp.47-53
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• 1987

충무권의 선로내에 관측선을 정하고 통항선박의 선적을 연속측정한 자료로서 항행중의 위험성과 조선상의 여유와 부담에 관하여 연구한 결과를 요약하면 다음과 같다. 1. 항행중의 위험성은 동항할 때 모두 항로의 동부보다 중앙부와 서부에서 비교적 높았다. 2. 조선상의 여유는 동항할 때는 선로의 서부, 서항할 때는 선로의 중앙부에서 가장 높았다. 그러나 서부입구에서는 동항할 때나 서항할 때 모두 가장 낮았다. 3. 조선상의 여유는 동항할 때나 서항할 때 모두 항로의 서부에서 높았고 동부에서 낮았다. 4. 조종성지수 T', K'는 모두 좌초위험지수 R에 영향을 미치나 T'가 K'보다 더 많은 영향을 미치는 것으로 나타났다

• 수산해양기술연구
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• 제23권2호
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• pp.1-1
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• 1987

충무권의 선로내에 관측선을 정하고 통항선박의 선적을 연속측정한 자료로서 항행중의 위험성과 조선상의 여유와 부담에 관하여 연구한 결과를 요약하면 다음과 같다. 1. 항행중의 위험성은 동항할 때 모두 항로의 동부보다 중앙부와 서부에서 비교적 높았다. 2. 조선상의 여유는 동항할 때는 선로의 서부, 서항할 때는 선로의 중앙부에서 가장 높았다. 그러나 서부입구에서는 동항할 때나 서항할 때 모두 가장 낮았다. 3. 조선상의 여유는 동항할 때나 서항할 때 모두 항로의 서부에서 높았고 동부에서 낮았다. 4. 조종성지수 T', K'는 모두 좌초위험지수 R에 영향을 미치나 T'가 K'보다 더 많은 영향을 미치는 것으로 나타났다

• 대한지역사회영양학회지
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• 제23권5호
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• pp.431-443
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• 2018

Objectives: Normal weight obesity (NWO) is defined as excessive body fat in the context of a normal body mass index (BMI). This condition carries a greater risk of developing noncommunicable chronic disease and has been associated with early inflammation. This study was conducted to compare the anthropometric measurements, eating behaviors, and blood clinical indices among four groups: underweight, normal, normal weight obesity and obesity. Methods: The subjects included 215 female college students. A questionnaire was administered regarding general characteristics, dietary behaviors, food consumption frequency. Anthropometric measurements and blood clinical indices were also investigated. Results: The average BMI, body fat percentage, waist circumference, fat-free mass, and muscle mass were highest in the obesity group (p<0.05). Most subjects had tried to lose weight and perceived that their health was worse than before they became college students. The ratio of students in the NWO group who thought their health was very poor was significantly higher than in the other three groups (p<0.05). The obesity and NWO groups seemed to eat more and their eating speed was significantly faster than the other groups (p<0.001). The consumption frequency of caffeinated beverages was significantly higher in the NWO group than in the other three groups (p<0.01). WBC was significantly higher in the obesity group (p<0.05). Serum levels of TG and total cholesterol were also significantly higher in the obesity group (p<0.05). Serum GPT was significantly higher in the obesity group (p<0.05) while BUN level was highest in the NWO group (p<0.05). Conclusions: The obesity group showed the most health problems while the NWO group seemed relatively healthy. However, NWO can lead to problems such as metabolic syndrome and cardiovascular disease in later life if poor dietary habits are maintained. Therefore, education in appropriate eating habits is needed for these subjects.

• 동의신경정신과학회지
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• 제22권4호
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• pp.87-100
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• 2011

Objectives : This study aims to evaluate the relationship between HRV indices and scores of emotional questionnaires and to find out the effective way to assess patients emotional and physical condition. Methods : We selected 144 patients who had both HRV data and BDI, STAI and STAXI scores on the chart among outpatients from July 2006 to December 2010. The relationship between the scores rated from the questionnaires and HRV indices are analyzed. And the HRV indices of patients included in the top 30 percent group and the bottom 30% group are compared. Results : 1. There were no significant correlations between HRV indices and scores of BDI, STAI and trait anger of STAXI. 2. SDNN and TP of HRV significantly decreased with higher state anger scores of STAXI. The top 30 percent group of state anger had lower SDNN, TP, LF, HF and HRV-index and higher pNN50 than the bottom 30 percent group. 3. RMSSD of HRV significantly decreased with higher anger-in scores of STAXI. The top 30 percent group of anger-in had lower RMSSD than the bottom 30 percent group. Conclusions : HRV can be used to evaluate emotional and physical changes related to state anger and inappropriate anger expression.