• Journal of the Korean Mathematical Society
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• v.55 no.3
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• pp.605-622
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• 2018

The original mixed multiplicity theory considered the class of mixed multiplicities concerning the terms of highest total degree in the Hilbert polynomial. This paper defines a broader class of mixed multiplicities that concern the maximal terms in this polynomial, and gives many results, which are not only general but also more natural than many results in the original mixed multiplicity theory.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.539-542
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• 2006

A volute (or scroll) of a centrifugal compressor collects the flows from impeller or diffuser, and passes it to a pipe at the exit. This flow still contains some kinetic energy which is not converted into pressure at diffuser, thus volute designer must concern the way to minimize losses. This study defines some variables which determine the shape of volute, and carry out computational analysis based on Design of Experiment to optimize the performance of volute.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.287-294
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• 2002

Underground flexible pipes for electric cables are subject to external loads and surrounding soil pressure. Particularly, strain of flexible pipes is of great concern in terms of safety and maintenance for electric cables. In this study, the actual size tests were carried out to investigate strain-deformation relation for underground flexible pipes subject to vehicle loads with various depths and degree of compaction.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.100-104
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• 2000

최근 인터넷의 사용이 폭증하며 기존 검색 엔진의 단점을 극복하고자 웹 에이전트 연구가 활성화 되고 있다. 이에 웹 에이전트의 구조에서 사용자의 관심, 비관심 문서의 분류 수집에 있어 직접적인 피드백에 의한 학습은 사용자에 부담과 불편을 제거하고자 간접적인 사용자 행위 분석에 의한 성향 학습 시스템을 제안한다.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.195-201
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• 1989

Voltage collapse is a serious concern to the electirc utility industry. It is common to associate steady-state stability with the ability of the transmission system to transport real power and to associate voltage collapse with the inability to provide reactive power at the necessary locations within the system. An algorithm to directly calculate the critical point of system voltage collapse was presented by the authors. The method (based on the ordinary power flow equations and explicit requirement of singularity of the Jacobian matrix) is basically one degree of freedom with proper load distribution factors. This paper suggests a modified algorithm to increase the degree of freedom, introducing the nonlinear programming technique. The objective function is a distance measure between the present operating point and the closest voltage collapse point. Knowledge of the distance and the most vulnarable bus from the voltage collapse point of view may be used as a useful index for the secure system operation.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.E
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• pp.1-11
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• 1992

Increasing national concern on nonpoint source pollution of surface and ground water Systems has led researchers and policy makers to develop certain agricultural Best Management Practices. As an initial step of broad study program above mentioned, this study reflected the effects of different tillage practice on bulk density and degree of saturation on two regional soils, namely Tama silt loam and Catlin silt loam. Results may help to clarify some of the conflicting findings on the impact of tillage systems on these parameters and it may also explain some of the reasons for specific role that different tillage systems play regarding nonpoint source pollution from agricultural fields.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.3
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• pp.177-188
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• 2019

Recently, citizens are feeling anxious as 'Motiveless Crime' increases. The quality of citizens life is degraded and the degree of crime fear is increasing. In this study, based on various variables related to crime other than actual crime occurrence status, crime occurrence points (point line polygon) felt by citizens are created by using mental map methodology. And the purpose of this study is to derive the area of concern for crime through spatial overlap analysis using kernel density estimation analysis. It also uses spatial overlay analysis using kernel density estimation to derive areas of concern for crime occurrence. As a result, the local residents' request point and the areas of concern for crime were overlapped. In addition, the mental map indicating the fear of crime was constructed by mapping mainly the areas between the facilities, the non-construction area such as the narrow area, the security CCTV, the streetlight. This study is meaningful in that it tried to derive a crime occurrence concern area by using mental map method unlike the previous study related to crime. The results of this study, such as mental map, could be used in various fields such as construction of fragile crime map, guideline of crime prevention through environment design.

• Journal of Nutrition and Health
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• v.35 no.3
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• pp.368-379
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• 2002

This study investigated the correlations among the health consciousness, nutrition knowledge, dietary habits and nutrition attitudes of school teachers. The subjects of this study were 75 male and 152 female leachers in elementary and middle schools in Masan city. The survey was conducted by using a questionnaire. Even though the average body mass index (BMI) and the obesity index were normal in both male and female subjects, 33.3% of the male subjects were overweight/obese, while 18.5% of the female subjects were underweight, according to the obesity index. The food components of most concern during mealtime were (in order of importance) salt, MSG and cholesterol by male subjects, and salt, fat and MSG by female subjects. The subjects considered self-relaxation as the most important factor in maintaining optimal health status, followed by resting, bathing or use ova sauna, moderation in diet, exercise, decreasing alcohol intake, and no smoking. Newspapers/magazines and TV/radio were the primary sources of nutrition and health information of the subjects. As the degree of health consciousness increased, scores of the dietary habits and nutrition attitudes increased. Nutrition knowledge scores and nutrition altitudes scores increased with subjects'increased level of perception of the importance of acquiring nutrition knowledge and nutrition information. There was a highly significant correlation between the degree of health consciousness and dietary habit score (${\gamma}$ : 0.3, p<0.001). The degree of health consciousness was also significantly correlated (${\gamma}$=0.6, p<0.001) with nutrition attitudes scores. But the correlation between the degree of health consciousness and nutrition knowledge was not statistically significant. The degree of the perception of the importance of nutrition knowledge showed a positive correlation with nutrition attitude (${\gamma}$:0.4, p<0.001) and dietary habit (${\gamma}$:0.3, p<0.001). The degree of perception about the importance of nutrition knowledge and nutrition information was positively correlated with nutrition knowledge (${\gamma}$:0.2, p<0.001) and nutrition attitudes (${\gamma}$:0.3, p<0.001).

• Journal of environmental and Sanitary engineering
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• v.21 no.1 s.59
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• pp.12-20
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• 2006

This paper was conducted concerning the degree of indoor air quality in public transport vehicles such as taxicabs, buses and subway trains, as sampled through the active participation of drivers and passengers in Seoul between 13th August 2005 and 2nd November 2005. The results were summarized as follows: 1. Among the measured substances especially respirable particulate matters ($PM_{10}$), total bacteria counts (TBC) and carbon dioxide ($CO_2$) exceeded the standard level of $150{\mu}g/m^3,\;800CFU/m^3$ and 1000ppm. 2. The concentration of carbon dioxide ($CO_2$) in taxi recorded 2491ppm, which is more than the standard amount of 1000ppm. This level was comparatively higher than all other public transportation methods. Total bacteria counts (TBC) in bus and subway recorded $1082CFU/m^3\;and\;1856CFU/m^3$, respectively. 3. The drivers who regularly work long hours showed the higher concern about contamination of the air inside the public transport vehicles and they considered it to be worse than the air outside. In contrast, the general public showed less concern about the air quality inside the public transport vehicles. However, they too acknowledged that the quality of the air inside the public transport vehicles was poor. In regards to the degree of indoor air quality in the public transport vehicles, a counterplan must be implemented urgently to effectively combat the excessive levels of $PM_{10}$, microorganism and $CO_2$. We need to gather more conclusive evidence pertaining to other possible contaminants and influencing factors.

• The Korean Journal of Community Living Science
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• v.25 no.3
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• pp.389-400
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• 2014

This study identified the mediating effect of the child's emotional expression on the relationship between the mother's empathy and the child's prosocial behavior. The participants included 310 mothers of children between the ages of 2 and 5 from two kindergartens and four day care centers located in Gyeonggi-do. The mother's empathy was measured using the Interpersonal Reactivity Index. The child's prosocial behavior was measured using the Preschoolers' Prosocial Behavior Index. The child's emotional expression was assessed using a questionnaire from previous research. First, older mothers and less educated mothers showed a higher level of empathy. Mothers over the age of 30 were more likely to have the ability to imagine other roles in movies or books, and to show empathic concern than those under 36. Mothers without a college degree showed a higher level of perspective-taking than those with a college degree. Second, girls were more likely to engage in prosocial behaviors and show emotional expressions than boys. Three-year-old children were more likely to share than two-year-old children, showed more initiative than two- and four-year-old children. Third, the mother's perspective-taking and empathic concern were significantly related to the child's prosocial behavior and emotional expression. The mother's personal distress was related to the child's control over emotions and awareness of other's emotion. Finally, the child's emotional expression had a mediating effect on the relationship between the mother's empathy and the child's prosocial behavior.