• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.1193-1198
• /
• 2007

The total number of passengers for Line $1{\sim}4$ operated by Seoul Metro among subways that act as foot of Seoul residents was 1.43116 billion passengers in 2006 and average of 3.921 million passengers per day. The results of analysis on safety accidents that occurred recently in subways show that various complaints on subways were reduced through the expansion of safety related facilities and training but accidents caused by negligent handling by employees including engineers are increasing on the contrary. At present time where various man-made accidents break out such as wrong handling and habits of engineers in charge of driving trains and momentary mistakes, there needs effort for active management and improvement to prevent and minimize accidents. Therefore, this study has drawn out problems through surveys on aptitude test system to engineers and compared with case studies in overseas. Thus, it attempted to minimize safety accidents in subways, and derived methods for improving safety management by focusing on improving the current aptitude test system for nurturing engineers suitable to handle railway driving in the future.

• Land and Housing Review
• /
• v.9 no.2
• /
• pp.21-31
• /
• 2018

The purpose of this study is to introduce the design and early implementation results of Choice Neighborhoods(Choice) initiative, which is the most recent version of public housing policies in the United States designed and implemented under the Obama administration. The Choice initiative aims to support a wide range of strategies locally driven to address problems in disadvantaged neighborhoods with an emphasis on a comprehensive approach to transforming those neighborhoods. In this study, first, I briefly review the history of public housing policies since 1937, particularly focusing on limitations of HOPE VI(Housing Opportunity for People Everywhere) projects to understand the context behind the advent of the program. Second, I introduce the overall design of the Choice program and point out how this programs' design differs from previous public housing programs by reviewing the literature on federal guidelines for the Choice program. This study particularly focuses on introducing social services given to existing residents in public housing and their neighborhoods in redevelopment processes. These social services are intended to address poverty-related problems that public housing residents often confront, to help them break out of the cycle of poverty, and to minimize the negative impacts of relocation triggered by redevelopment. Third, to examine how this program has been implemented and has revealed limitations so far, I review an interim evaluation report based on five cities. This study ends with discussing policy implications for public housing providers and housing policy-makers in South Korea.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.11
• /
• pp.3221-3224
• /
• 2010

This study investigates the requirements of lithium-air cathodes, which directly influence discharge capacity. The cathodes of Li-air cell are made by using five different carbon materials, such as Ketjen black EC600JD, Super P, Ketjen black EC300JD, Denka black, and Ensaco 250G. The Ketjen black EC600JD provides discharge capacity of 2600 mAh/g per carbon weight, while that of Ensaco 250G shows only 579 mAh/g. To figure out the differences of discharge capacity from carbon materials, their surface area and pore volume are analyzed. These are found out to be the critical factors in determining discharge capacity. Furthermore, carbon loading on Ni foam and amounts of electrolyte are significant factors that affect discharge capacity. In order to investigate catalyst effect, electrolytic manganese dioxide (EMD) is incorporated and delivered 4307 mAh/g per carbon weight. This infers that EMD facilitates to break $O_2$ interactions and leads to enhance discharge capacity.

• Nuclear Engineering and Technology
• /
• v.46 no.6
• /
• pp.817-824
• /
• 2014

To ensure the safety of research reactors, the water level must be maintained above the required height. When a pipe ruptures, the siphon phenomenon causes continuous loss of coolant until the hydraulic head is removed. To protect the reactor core from this kind of accident, a siphon breaker has been suggested as a passive safety device. This study mainly focused on two variables: the size of the pipe rupture and the timing of air entrainment. In this study, the size of the pipe rupture was increased to the guillotine break case. There was a region in which a larger pipe rupture did not need a larger siphon breaker, and the water flow rate was related to the size of the pipe rupture and affected the residual water quantity. The timing of air entrainment was predicted to influence residual water level. However, the residual water level was not affected by the timing of air entrainment. The experimental cases, which showed the characteristic of partical sweep-out mode in the separation of siphon breaking phenomenon [2], showed almost same trend of physical properties.

• Korean Journal of Psychosomatic Medicine
• /
• v.5 no.1
• /
• pp.129-134
• /
• 1997

The meddle years start when persons achieve maturity and end when they realize they are old, and we commonly call ages between thirty-live and sixty five the middle years. Thinking of life as a play, the middle years lead up to and away from the climax of the plot. In the early part of middle age, the man is the main support of his family, and is out to establish himself in his career. He is in a race toward success, and may acquire a sponsor who picks him out as a protege. In the middle part of middle age, the man is ready to come into his own and may break with his sponsor. Most persons are now at the height of their potential, know their areas of competence, and have the satisfaction of feeling in control in them. They need no longer prove themselves from day to day, for they are credited with past accomplishments. Some are caught in "promotion or success depression", and some continue to change jobs creating difficulties is readjustment. The more satisfactory changes usually occur within a career rather than through shifiting careers. In e later part of the middle age the man worries about his physical health, and experiences depression in facing the retirement. Woman frequently change the course of their lives some time between the ages of thirty-five and forty, and may resume their education or careers. Tee quarters of women are passing through "involutional melancholia".

• The Korean Journal of Food & Health Convergence
• /
• v.5 no.3
• /
• pp.7-20
• /
• 2019

The use of caffeine as a psychoactive stimulant in tea has been observed to have serious negative effects in humans' systems such as respiratory, nervous, cardiovascular, renal and skeletal systems. This study was carried out to assess the levels of caffeine in 10 different tea brands available in local market in Dutse, Jigawa State, Nigeria. Quantitative analysis of caffeine was performed by a simple and fast UV-Vis spectrophotometric methods using different solvents for extraction. The caffeine content in all the tea samples analyzed in this study were below the maximum allowable limits set by the USFDA. Tea have been associated with adverse health effects and the claims made by manufacturers about the benefits of tea do not highlight risks associated with excessive consumption of a combination of the ingredients contained in tea. Long term effects of tea consumption of children and young people have not been adequately studied. Therefore, it is recommended that further research be carried out on the adverse effects of energy drinks on children. Research is also needed to be done on the effects of the combination of ingredients on health and excessive consumption of those ingredients to children and adolescents. People need to be educated and given proper awareness on the health risks associated with caffeine containing beverages.

• The Journal of Information Systems
• /
• v.31 no.2
• /
• pp.1-18
• /
• 2022

Purpose Customer review is a major factor in choosing certain restaurants. This study investigates the key factors affecting customer's evaluation about restaurants. With the recent intensification of competition among restaurants in the service industry, the analysis results are expected to provide in-depth insights for enhancing customer experiences. Design/methodology/approach We collected information and reviews provided at the restaurants in the Kakao Map platform. The information collected is based on the information of 3,785 restaurants in Daegu registered on Kakao Map. Based on the information collected, seven independent variables, including number of rating registered, number of reviews, presence or absence of safe restaurants, presence or absence of a posting about holding facilities, presence or absence of a posting about business hours, presence or absence of a posting about hashtags, and presence or absence of break times, were used. Dependent variable is restaurant rating. Multiple regression between independent variables and restaurant rating was carried out. Findings The results of the study confirmed that number of rating registered, presence or absence of a posting about business hours, and presence or absence of a posting about hash tags have an positive effects on the restaurant rating. The number of reviews had a negative effect on the restaurant rating. In addition, in order to confirm the role of customer's reviews, we carried out LDA topic modeling. We divided the topics into the positive review and the negative reviews.

• Journal of the korean Society of Automotive Engineers
• /
• v.7 no.1
• /
• pp.48-54
• /
• 1985

One of the most probable reason of the apex seal damage in IR-2500 industrial Wankel (rotary) engine was believed to be the engine detonation. Both analytical and experimental studies were made with a view th find out engine detonation pressure. The stagnation detonation pressure $p_{03}$' was estimated based on the data from IR-2500 engine detonation tests, such as engine firing pressure, state of fresh charge at BDC and polytropic compression exponent. The estimated stagnation detonation pressure for the natural gas fueled IR-2500 engine was in excess of 3,700 psia. With natural gas liquid added to the natural gas the octane value of the fuel was lowered, thus, making the engine more prone to detonate. The estimated detonation pressure for the case with the mixed fuel was about 3,400 psia which was sufficiently high to break the apex seal. The subsequent engine lab tests performed on two identical engines with sole difference in the apex seal thickness between the two engines proved that the engine knock, in fact, was the villain of the apex seal failure.ilure.

• 보존과학연구
• /
• s.22
• /
• pp.81-92
• /
• 2001

The replica experiment of golden bell excavated from the East Three-Story Pagoda at the Gamunsa temple was carried out in order to know the handiwork technique of ancient granule. The size of 0.3mm granule was attached to the golden bell which was 3.4mm bell body by soldering. When we tried to attach the granule by a modern metalwork, we could know that this technique was hard to make the replica bell. We could prove how to adhere strongly to the golden granule by tension testing. First of all, we made the soldering of the same composition as the golden bell excavated from the Gamunsa temple and then prepared specimens for testing to measure the tension strength. It showed that the broken position was not a soldering part. This result showed how the ancient granule could maintain without a break for a long time.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.33 no.4
• /
• pp.511-518
• /
• 2009

Freed from its traditional confinement to the human body, postmodernism in fashion exposes the defectiveness of body and abstracts from the body under. Deformation of the body denotes the break away from the idealized and standardized body for mass productions. It tends to experiment with extreme exaggeration in form, refusing to subscribe to the traditional values that build on the balance and symmetry of the body. Bodily deformation carried out historical and cultural pastiche opposes the sartorial convention and symbolism which results in the discord between signifiant and $signifi{\acute{e}}$ of clothing. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze bodily deformation as pastiche, focusing on the relationship between clothes and the body. In order to inquire the deformation of the body in fashion, my study examines subjects of the fashion collections of the turn of the 21st century, using the method of literature research and content analysis.