• Transactions of the Korean hydrogen and new energy society
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• v.28 no.1
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• pp.56-62
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• 2017

Although most electricity production contributes to air pollution, the vehicle organizations and environmental agency categorizes all EVs as zero-emission vehicles because they produce no direct exhaust or emissions. Currently available EVs have a shorter range per charge than most conventional vehicles have per tank of gas. EVs manufacturers typically target a range of 160 km over on a fully charged battery. The energy efficiency and driving range of EVs varies substantially based on driving conditions and driving habits. Extreme outside temperatures tend to reduce range, because more energy must be used to heat or cool the cabin. High driving speeds reduce range because of the energy required to overcome increased drag. Compared with gradual acceleration, rapid acceleration reduces range. Additional devices significant inclines also reduces range. Based on these driving modes and climate conditions, this paper discusses the performance characteristics of EVs on energy efficiency and driving range. Test vehicles were divided by low / high-speed EVs. The difference of test vehicles are on the vehicle speed and size. Low-speed EVs is a denomination for battery EVs that are legally limited to roads with posted speed limits as high as 72 km/h depending on the particular laws, usually are built to have a top speed of 60 km/h, and have a maximum loaded weight of 1,400 kg. Each vehicle test was performed according to the driving modes and test temperature ($-25^{\circ}C{\sim}35^{\circ}C$). It has a great influence on fuel efficiency amd driving distance according to test temperature conditions.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1417-1428
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• 2020

The design of a nuclear reactor core requires basic thermal-hydraulic information concerning the heat transfer regime at which onset of nucleate boiling (ONB) will occur, the pressure drop and flow rate through the reactor core, the temperature and power distributions in the reactor core, the departure from nucleate boiling (DNB), the condition for onset of flow instability (OFI), in addition to, the critical velocity beyond which the fuel elements will collapse. These values depend on coolant velocity, fuel element geometry, inlet temperature, flow direction and water column above the top of the reactor core. Enough safety margins to ONB, DNB and OFI must-emphasized. A heat transfer package is used for calculating convection heat transfer coefficient in single phase turbulent, transition and laminar regimes. The main objective of this paper is to study the possibility of power upgrading of WWR-S research reactor from 2 to 10 MW_th. This study presents a one-dimensional mathematical model (axial direction) for steady-state thermal-hydraulic design and analysis of the upgraded WWR-S reactor in which two types of plate fuel elements are employed. FOR-CONV computer program is developed for the needs of the power upgrading of WWR-S reactor up to 10 MW_th.

• Journal of Korea Ship Safrty Technology Authority
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• s.23
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• pp.2-13
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• 2007

With the effectuation of the amendment of MARPOL 73/78 on 5 April 2005, enforcement regulations of Marine Pollution Prevention Act were revised in domestic on 12 March 2005 that double hull structure was required to the small single bottom oil tankers under DWT(deadweight tonnage) 500 ton for the protection of the marine pollution casualties. The objective of this study is to develop the double bottom structure of small oil tanker under DWT 500 ton with superior crashworthiness and to establish its suitable standard to double bottom structure. The promoting strategy of this R&D is classified into the crashworthy structural analysis of small oil tankers using LS/DYNA3D code and the examination of their damage stabilities according to tonnage. It could be thought that the desirable inner bottom height should be above the B/7.5 and its minimum height 0.65m for the domestic small oil tanker under DWT 500ton.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.2
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• pp.231-239
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• 2002

This paper gives a comprehensive overview of the SSO solution design on the intranet. SSO described in this paper is based on LDAP, PKI and CA. We designed the data structure to hold many various application services by changing the attribute and DN of LDAP DB. We built LDAP DB using the employee records stored in our organization database. LDAP DB is routinely updated from the database. CA Server that depends on PKI is used to issue the certificates. SHTTP based on SSL is used to protect the data between certificate server and the intranet users.

• Animal Bioscience
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• v.37 no.4
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• pp.600-608
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• 2024

Objective: In this study, we aimed to evaluate the usability single nucleotide polymorphisms (SNPs) for parentage testing of horse breeds in Korea. Methods: The genotypes of 93 horse samples (38 Thoroughbred horses, 17 Jeju horses, 20 Quarter horses, and 18 American miniature horses) were determined using 15 microsatellite (Ms) markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3, and VHL20) and 101 SNP markers. Results: Paternity tests were performed using 15 Ms markers and 101 SNP markers in Thoroughbred horses and Quarter horses. AHT5, ASB2, ASB17, ASB23, CA425, HMS7, HTG10, and LEX3 did not follow Mendelian inheritance in Thoroughbred horses, whereas in Quarter horses, only AHT4, ASB2, and HMS2 showed Mendelian inheritance, consequently, paternity was not established. Meanwhile, 31 markers, including MNEc_2_2_2_98568918_BIEC2_502451, in Thoroughbred horses, and 30 markers, including MNEc_2_30_7430735_BIEC2_816793, in Quarter horses did not conform with Mendelian inheritance and therefore, could not be used for establishing parentage. Conclusion: The possibility of replacing Ms markers with SNP markers for paternity testing in horses was confirmed. However, further research using more samples is necessary.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.4
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• pp.65-83
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• 1999

This study is intended to build a cross-reference system as syndetic device to provide bibliographic relations and to collocate variant access points through references, by developing a reference record format. To this end, the method of this study are as follows: First, the roles of references, which have long been used in traditional records, have been reviewed. Second, ways in which references are depicted not only by current cataloging rules but also by authority control systems are examined. Major characteristics of the reference record are summarized as fellows: 1) If variations either of an author name or of a title are made, or any related works are published, only a single reference record is created. This record uses existing authority records, and instead of adopting authority headings, it will expand the function of the explanatory reference as well as newly implementing a relational reference which can later be used as a reference record. 2) All the variations of identical personal or group names and of lilies are dealt as one access point. In place of current 'see' and 'see also' references, not drawing lines between authority heading(1XX field), 'see'(4XX field) and 'see also' reference(5XX field), all forms of names will be simply applied to record field '1XX'. 3) Any form of data elements, which are used as access points, will be described in '1XX' which has equal value. When a need arises to explain relationships between various access points, it can be met by applying the general explanation reference-name(666 field). Similarly, when there is a need to articulate bibliographic relationships between related works, they will be suggested through the title and relational reference. 4) The title and relational reference regulates related terms that each relation type contains its field, according to each relational type, by reclassifying entire fields in order to provide direct bibliographic relation types on reference records. 5) Pointers which are connected to each access point present reference control numbers.

• The Mathematical Education
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• v.48 no.2
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• pp.149-167
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• 2009

This study was aimed to examine problem-solving ability of fifth graders on two types of mathematical essay problems, and to analyze the process of mathematical justification in solving the essay problems. For this purpose, a total of 14 mathematical essay problems were developed, in which half of the items were single tasks and the other half were data-provided tasks. Sixteen students with higher academic achievements in mathematics and the Korean language were chosen, and were given to solve the mathematical essay problems individually. They then were asked to justify their solution methods in groups of 4 and to reach a consensus through negotiation among group members. Students were good at understanding the given single tasks but they often revealed lack of logical thinking and representation. They also tended to use everyday language rather than mathematical language in explaining their solution processes. Some students experienced difficulty in understanding the meaning of data in the essay problems. With regard to mathematical justification, students employed more internal justification by experience or mathematical logic than external justification by authority. Given this, this paper includes implications for teachers on how they need to teach mathematics in order to foster students' logical thinking and communication.

• Korean Security Journal
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• no.6
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• pp.273-289
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• 2003

The purpose of this study is to explore the underlying causes of the development of private security in the United States. These include the increasing crime rates and fear of crime, the poor performance of public policing, the decentralization of political authority, the increase of mass private property, economic growth and increase of personal income, commodification of security, insurance companies' demand for tighter security and fear of litigation, and historical events such as World War I & II. Based on the findings of this study, it is suggested that no single factor would account for the growth of private security in the United States. In other words, the rapid growth of private security in the United States should be attributed to the interrelated influences of the factors given above. Finally, it might be the contribution of this study that the future development of private security in Korea would be guided by understanding the case of the United States because of the similarities of the developmental process in private security industry of two countries.

• Proceedings of the Safety Management and Science Conference
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• 2010.11a
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• pp.581-591
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• 2010

Korea Rail Network Authority ordered Urban Transit Magrev System on the alternative tender lines. The project was contained order with GS Construction and Yooshin Corporation as a result of competition as 5 consortium. Urban Transit Magrev System route was constructed in the whole Yeongjong-dong and Yongyu-dong, Jung-gu, Inchen. The main project is via transportation center in Inchen Int'l airport ~ Work complex ~ Water park ~ Yongyu-station and has Total continuation of 6.1kilometers, Station of 6 spot, Car base of a spot, go out line(a single line) of 380meters. Scale of construction is Major of Roadbed, Railroad, Building, Inspection and Repair facilities. The first Urban Transit Magrev System in Korea is a new symbol of Korea and has polished beauty and creative artistry based on functional perfection. It was designed in harmony with Inchen Int'l Airport improving the dignity of SOC design.

• YAKHAK HOEJI
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• v.58 no.4
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• pp.277-285
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• 2014

The purpose of this study is to provide the comparative study results for the purpose of the developing continuing professional educational systems for Korean pharmacists. The professional continuing educational systems of the UK, USA, Japan and Korea were analyzed. General Pharmaceutical Council in UK controls the pharmacy professions for the protection of the health of the citizens in UK and certifies the schools of pharmacy and the continuing education providers. The USA and Japan have the several accreditation bodies for the pharmacy education and the continuing pharmaceutical education. However, the quality assurance systems in Korea for the continuing education and specialty programs are not implemented, yet. The renewal system of the pharmacist license should be introduced like the health care providers like doctors to improve professionalism. Finally, it is recommended that all of these things should be done by a single administrative authority such as Korean Accreditation Council for Pharmacy Education.