• Journal of Korean Association for Spatial Structures
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• v.9 no.4
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• pp.89-96
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• 2009

Apartment is the most favorite residential type which already occupies more than 50 percent of total number of housing unite in Korea. The interior space design shows various changes of trends within old and legal standard in terms of basic dimension. The most important function of housing means that Provides comfortable living spaces for a family and enjoying relaxation of stress form social activities. This residential space effects direct or indirect to each family members self-satisfaction and relationship. The basic factor for space design brings dimension which is enable space efficiency together with behavioral route, size of electronics and furnitures. Apartment dwelling type was introduced from out of countries. From the very beginning that inharmonious conflicts found and adjusted for several decades. But, the changes of body conditions of new generation has not considered as a dwelling space design yet. This research may call for attention of changing human scale standards for housing in various field of study.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.31 no.1
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• pp.237-255
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• 2020

Pareto principle states that, for many events, roughly 80% of the effects come from 20% of the causes. This study clarified if there is Pareto principle in Korean universities' academic information resource sharing network and calculates the Gini efficient about inequality in sharing academic resources. As a result, top 20% libraries led 80% of performance and inequality degree showed 0.8 as very serious condition. Relative Gini efficient which is recalculated considering scale of each libraries stay 0.7 that is adjusted slightly down. It means that such phenomenon is not caused by the difference of each universities scale with high contribution of big university and low contribution of small university. And in comparison of inequality between university's types, inequality between community colleges and private universities is more serious than four-year-course college and national university respectfully. Finally, as a result of visualizing the distribution of participating libraries, there were libraries with overwhelming contributions, and libraries with small but relatively high contribution levels were also distributed.

• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.501-508
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• 2003

Artificial coupling of one enzyme with another can provide an efficient means for the production of industrially important chemicals. Xylose reductase has been recently discovered to be useful in the reductive production of xylitol. However, a limitation of its in vitro or in vivo use is the regeneration of the cofactor NAD(P)H in the enzyme activity. In the present study, an efficient process for the production of xylitol from D-xylose was established by coupling two enzymes. A NADH-dependent xylose reductase (XR) from Pichia stipitis catalyzed the reduction of xylose with a stoichiometric consumption of NADH, and the resulting cofactor $NAD^+$ was continuously re-reduced by formate dehydrogenase (FDH) for regeneration. Using simple kinetic analyses as tools for process optimization, suitable conditions for the performance and yield of the coupled reaction were established. The optimal reaction temperature and pH were determined to be about $30^{\circ}C$ and 7.0, respectively. Formate, as a substrate of FDH, affected the yield and cofactor regeneration, and was, therefore, adjusted to a concentration of 20 mM. When the total activity of FDH was about 1.8-fold higher than that of XR, the performance was better than that by any other activity ratios. As expected, there were no distinct differences in the conversion yields of reactions, when supplied with the oxidized form $NAD^+$ instead of the reduced form NADH, as a starting cofactor for regeneration. Under these conditions, a complete conversion (>99%) could be readily obtained from a small-scale batch reaction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.1916-1922
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• 2009

Introducing distributed generators(DGs) to utility distribution system can cause malfunction of relay on the grid when ground faults or severe load unbalances are occurred on the system. Because DGs interconnected to the grid can contribute fault currents and make bidirectional power flows on the system, fault currents from DGs can cause an interference of relay operation. A directional over current relay(DOCR) can determine the direction of power flow whether a fault occurs at the source side or load side through detecting the phases of voltage and current simultaneously. However, it is identified in this paper that the contributed fault current(Ifdg) from the ground source when was occurred to contribute single-line-to-ground(SLG) fault current, has various phases according to the distances from the ground source. It means that the directionality of Ifdg may not be determined by simply detecting the phases of voltage and current in some fault conditions. The magnitude of Ifdg can be estimated approximately as high as 3 times of a phase current and its maximum is up to 2,000 A depending on the capacity of generation facilities. In order to prevent malfunction of relay and damage of DG facilities from the contribution of ground fault currents, Ifdg should be limited within a proper range. Installation of neutral ground reactor (NGR) at a primary neutral of interconnection transformer was suggested in the paper. Capacity of the proposed NGR can be adjusted easily by controlling taps of the NGR. An algorithm for unidirectional relay was also proposed to prevent the malfunction of relay due to the fault current, Ifdg. By the algorithm, it is possible to determine the directionality of fault from measuring only the magnitude of fault current. It also implies that the directionality of fault can be detected by unidirectional relay without replacement of relay with the bidirectional relay.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.6
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• pp.415-424
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• 2004

In this paper, we introduce and investigate a new category of rule-based fuzzy inference system based on Information Granulation(IG). The proposed rule-based fuzzy modeling implements system structure and parameter identification in the efficient form of “If..., then...” statements, and exploits the theory of system optimization and fuzzy implication rules. The form of the fuzzy rules comes with three types of fuzzy inferences: a simplified one that involves conclusions that are fixed numeric values, a linear one where the conclusion part is viewed as a linear function of inputs, and a regression polynomial one as the extended type of the linear one. By the nature of the rule-based fuzzy systems, these fuzzy models are geared toward capturing relationships between information granules. The form of the information granules themselves becomes an important design features of the fuzzy model. Information granulation with the aid of HCM(Hard C-Means) clustering algorithm hell)s determine the initial parameters of rule-based fuzzy model such as the initial apexes of the membership functions and the initial values of polynomial function being used in the Premise and consequence Part of the fuzzy rules. And then the initial Parameters are tuned (adjusted) effectively with the aid of the improved complex method(ICM) and the standard least square method(LSM). In the sequel, the ICM and LSM lead to fine-tuning of the parameters of premise membership functions and consequent polynomial functions in the rules of fuzzy model. An aggregate objective function with a weighting factor is proposed in order to achieve a balance between performance of the fuzzy model. Numerical examples are included to evaluate the performance of the proposed model. They are also contrasted with the performance of the fuzzy models existing in the literature.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.216-221
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• 1989

Soaking of soybeans and the subsequent effect on cooking kinetics were investigated by the means of puncture test and shear press with Instron universal testing machine. Soaked soybeans were water cooked at temperatures of $90{\sim}135^{\circ}C$ adjusted with oil bath. Instron puncture force of 0.15kg and shear force of 1.2kg/g-soybean were appeared as the eating soft texture by sensory evaluation. Softening activation energies of yellow soybeans for puncture and shear force were 14,540cal/g-mole and 21,374cal/g-mole. z-values were calculated as $42.1^{\circ}C$ and $37.4^{\circ}C$, respectively.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2477-2484
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• 1997

Best-first heuristic search algorithm, such as $A^{\ast}$ algorithm, are one of the most important techniques used to solve many problems in artificial intelligence. A common feature of heuristic search is its high computational complexity, which prevents the search from being applied to problems is practical domains such as route-finding in road map with significantly many nodes. In this paper, several heuristic search algorithms are concerned. A new dynamic weighting heuristic method called the pat-sensitive heuristic is proposed. It is based on a dynamic weighting heuristic, which is used to improve search effort in practical domain such as admissible heuristic is not available or heuristic accuracy is poor. It's distinctive feature compared with other dynamic weighting heuristic algorithms is path-sensitive, which means that ${\omega}$(weight) is adjusted dynamically during search process in state-space search domain. For finding an optimal path, randomly scattered road-map is used as an application area.

• Journal of the Korean Society of School Health
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• v.28 no.1
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• pp.1-9
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• 2015

Purpose: The purpose of this study is to examine the effect of sleep duration on suicidal ideation in Korean adolescents. Methods: This study used the data drawn from Korea Youth Risk Behavior Web-Based Survey in 2013. A total data of 63,301 adolescents were included in the analysis. Included variables were general characteristics, health status variables, hours of sleep, and suicidal ideation. For sample description weighted percentage and means were used. Rao-Scott ${\chi}^2$ test and simple and multiple logistic regression with dummy variables were conducted with use of SAS 9.2. Results: Among general characteristics and health status variables, gender, grade, school level, school achievement, family's economic status, living with parents, subjective health, happiness, stress, and feeling of despair were found to be significantly related to suicidal ideation. Rates of having suicidal ideation were 22.4% in the case of students with less than 5 hours of sleep and 12.9% in students with 8 or more hours of sleep. After controlling general characteristics and subjectively perceived variables, hours of sleep was still significantly related to suicidal ideation. That is, compared to adolescents with 8 hours or more of sleep, those with less than 5 hours of sleep showed significantly higher risk for having suicidal ideation (adjusted odds ratio: 1.20, p<.001). Conclusion: These findings suggest that short sleep has negative effects on psychological health in adolescents. Particularly, less than 5 hours of sleep has harmful effect on adolescents' increased risk for having suicidal ideation.

• Journal of Preventive Medicine and Public Health
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• v.42 no.6
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• pp.392-402
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• 2009

Objectives : The aims of this paper were to develop the composite deprivation index (CDI) for the sub-district (Eup-Myen-Dong) levels based on the theory of social exclusion and to explore the relationship between the CDI and the standardized mortality ratio (SMR). Methods : The paper calculated the age adjusted SMR and we included five dimensions of social exclusion for CDI; unemployment, poverty, housing, labor and social network. The proxy variables of the five dimensions were the proportion of unemployed males, the percent of recipients receiving National Basic Livelihood Security Act benefits, the proportion of households under the minimum housing standard, the proportion of people with a low social class and the proportion of single-parent household. All the variables were standardized using geometric transformation and then we summed up them for a single index. The paper utilized the 2004-2006 National Death Registry data, the 2003-2006 national residents' registration data, the 2005 Population Census data and the 2005-2006 means-tested benefit recipients' data. Results : The figures were 115.6, 105.8 and 105.1 for the CDI of metropolitan areas (big cities), middle size cities and rural areas, respectively. The distributional variation of the CDI was the highest in metropolitan areas (8.9 - 353.7) and the lowest was in the rural areas (26.8 - 209.7). The extent and relative differences of deprivation increased with urbanization. Compared to the Townsend and Carstairs index, the CDI better represented the characteristics of rural deprivation. The correlation with the SMR was statistically significant and the direction of the CDI effects on the SMR was in accordance with that of the previous studies. Conclusions : The study findings indicated mortality inequalities due to the difference in the CDI. Despite the attempt to improve deprivation measures, further research is warranted for the consensus development of a deprivation index.

• Journal of Preventive Medicine and Public Health
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• v.52 no.6
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• pp.355-365
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• 2019

Objectives: In rural areas of Korea, where public transportation infrastructure is lacking and alternative systems are poor, the elderly experience inconveniences in using healthcare, although their need is high. This study aimed to analyze the association between the convenience of transportation and unmet healthcare needs among the rural elderly. Methods: The data used were collected in the 2016 Community Health Survey among rural elderly individuals aged 65 or older. Dependent variable was the unmet healthcare needs, explanatory variable was the convenience of transportation. The elderly were divided into 3 groups: with no driver in the household, with a driver, and the elderly individual was the driver (the self-driving group). Covariates were classified into predisposing, enabling, and need factors. They included gender, age, education, income, economic activity, household type, motor ability, subjective health level, number of chronic diseases, anxiety/depression, and pain/discomfort. The data were analyzed using logistic regression and stratification. Results: A significant association was found between the convenience of transportation and unmet healthcare needs. When examined unadjusted odds ratio of the group with a driver in the household, using the group with no driver as a reference, was 0.61 (95% confidence interval [CI], 0.54 to 0.68), while that of the self-driving group was 0.34 (95% CI, 0.30 to 0.38). The odds ratios adjusted for all factors were 0.69 (95% CI, 0.59 to 0.80) and 0.79 (95% CI, 0.67 to 0.91). Conclusions: We confirmed a significant association between inconvenient transportation and unmet healthcare needs among the rural elderly even after adjustment for existing known factors. This implies that policies aimed at improving healthcare accessibility must consider the means of transportation available.