• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.36-42
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• 2014

Domestic 105mm HE (High Explosive) shell is composed of three parts that are Fuze, Projectile and Propellants. Among three parts, propelling charge of propellants part consists of single base propellants. It has been known that the lifespan of single base propellants is affected by a storage period. These are because Nitrocellulose (NC) which is the main component of propelling gunpowder can be naturally decomposed to unstable substances similar with other nitric acid ester. Even though it cannot be prevented fundamentally from being disassembled, a decomposition product ($NO_2$, $NO_3$, and $HNO_3$) and tranquillizer DPA (Diphenylamine) having high reactivity are added into a propellant to restrain induction of automatic catalysis by a decomposition product. The decay rate of the tranquillizer is also affected by a production rate of the decomposition product of NC. Therefore, an accurate prediction of the Self-Life is required to ensure against risks such as explosion. Hereupon, this paper presents a new methodology to estimate the shelf-life of single base propellants using data of ASRP (Ammunition Stockpile Reliability Program) to domestic 105mm HE (propelling charge of propellants part). We selected four attributes that are inferred to have influence on distribution of the DPA amount in a propellant from the ASRP dataset through data mining processes. Then the selected attributes were used as independent variables in a regression analysis in order to estimate the shelf-life of single base propellants.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.136-136
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• 2003

Calcium lactate has been known extending shelf-life of several lactic acid fermented foods through buffer action with lactic acid and binding of calcium and pectic polysaccharides in the tissue. But, the effects in kimchi during storage and distribution has not been observed. Calcium lactate is tasteless, nontoxic compounds commonly used in a number of food products. Recent observations have indicated the potential usefulness of calcium lactate as food additive which has anticariogenic-, antimicrobial-, anticalculus, anti- carcinogenic effects and enhancement of bone mineral density. In this work we determined the effects of calcium lactate(CaL)-treatment(0, 1, 2 and 3% against salted Chinese cabbage) on the pH, acidity, microbial counts, content of alcohol insoluble substance and calcium texture, color, scanning electron microscopic observation of kimchi tissue and sensory test during storage. pH of CaL treated kimchi were higher(3.78∼3.92) than that of control products(3.58). Total microbe(TM) of CaL treated kimchis were lower but ratio of lactic acid bacteria against TM was higher than those of control products, respectively. Calcium content of treated products were 3-5 times higher than control products. The hardness and crispy taste of treated products were remarkably higher than those of control products evaluated by SEM observation AIS analysis, sensory and textural analysis. Moreover, evaluation on the pH, acidity and sensory test showed the shelf-life of treated kimchi(CaL 2%) to be 25-30 days, which was 13-15 days longer than that of control products.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.3
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• pp.411-430
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• 1994

The denture may be fractured accidentally by an impact while outside the mouth, or may be cracked or broken while in service in the mouth. The latter is generally a fatigue failure caused by repeated flexure over a period of time. This investigation compared the flexural fatigue resistance, the impact force and the transverse strength of two denture base materials with and without the grid strengthener, the T300, the T800 and the Kevlar fiber to evaluate the fracture resistance. The distribution and behavior of fibers across fracture lines were examined by Hi-Scope Compact Microvision System. Through analyses of the data from this study, the following conclusions were obtained. 1. The flexural fatigue resistance, impact strength and transverse strength of high impact strength resin were higher than those of conventional heat polymerizing resin, but statistically there was no significant difference(p>0.05). 2. All specimens with and without the grid strengthener did not show significant differences in the flexural fatigue, the impact and the transverse strength test(p>0.05). 3. All specimens reinforced with the T300, the T800 and the Kevlar fiber showed significant increase of the fatigue resistance and the impact force(p<0.05). 4. All specimens reinforced with the T800 and the Kevlar fiber showed significant increase of the transverse strength(p<0.05). 5. All specimens reinforced with the T300, the T800 and the Kevlar fiber exhibited greenstick fractures. The fibers tended to remain enveloped in the resin, resisting pull-out.

• The Journal of Society for e-Business Studies
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• v.10 no.2
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• pp.1-19
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• 2005

Due to the phenomenal growth in mobile internet users, mobile business as a type of applications of mobile internet has attracted the related industries' and academic researchers' attentions. However, most researchers focus on the issues of Mobile B2C collecting survey questions from consumers or internet users. This paper points out that Mobile B2B has distinct service sector and analyzes the current trend and demand of Mobile B2B in Korea by collecting survey questionnaire from specialists in mobile industries and people in universities and research institutes. Survey fields include business, market, contents/application, research and development and legal system. According to the survey results, Mobile B2B business will rise in distribution, finance, sales, and logistics industries from the beginning of 2005 using wireless PDA and the important preconditions will be security, certification, and standardization.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.97-103
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• 2020

Linux Cgroups takes a fundamental role for sharing system resources among multiple containers on container-based cloud computing environment. Especially for I/O resource, Linux Cgroups supports a mechanism for sharing I/O bandwidth in proportion to I/O weight. However, the current mechanism of Linux Cgroups using BFQ I/O scheduler seriously degrades the I/O performance with high bandwidth storage device such as NVMe SSDs. In this paper, we proposed a new feedback based I/O bandwidth sharing scheme for Linux Cgroups which allocates I/O credits to containers according to I/O weights and adjusts the amount of credits to performance fluctuation of NVMe SSDs. The proposed scheme is implemented on Linux kernel 5.3 and evaluated. The evaluation results show that it can share the I/O bandwidth among multiple containers proportionally to I/O weights while improving I/O performance more than twice as high as the existing scheme.

• Journal of Digital Convergence
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• v.12 no.12
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• pp.449-456
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• 2014

This study aimed to reveal the statistical correlation between the distribution of jurisdictional population and the incidence of mobilization, which consisted with cases of patient transfer and non-transfer to hospital. For this study, we collected and analysed the data for populational status, area, and cases of patient transfer and non-transfer to hospital from 5 fire stations in D city, from January 2010 to December 2012. Total numbers of mobilization were highest in J fire station and this supreme tendency were also seen in both cases (transfer and non-transfer). On the contrary, those of B fire station were lowest. In case of populational status of specific jurisdiction, S fire station was identified to possess the highest while D fire station showed the lowest. However, influences of jurisdictional population on occurrence of patient transfer and / or non-transfer to hospital were not seemed to be shown.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.2
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• pp.197-204
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• 2014

This paper investigates a design of optimization database structure layout of Message Oriented Analysis and Management Tool (MOMAT) for naval combat systems (NCS). The NCS is composed of heterogeneous and large-scale component such as communication service and data distribution servcies (DDS). Each components are massively made the data as components. To manage the messages, MOMAT is developed. Typical modeling tool have problems that low performance due to duplicate database tables. An efficient design that one of the database optimization is proposed to solve the problems in this paper. It reduces the number of tables and improves application response and processing time. Experiment results shows that an availability of proposed method in MOMAT and decrease of both amount of data from client node to server and sever load.

• Korea Journal of Hospital Management
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• v.18 no.2
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• pp.15-32
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• 2013

Few public health researchers have paid research attention to the location of medical institutions in Korea. Previous studies were published in geography journals, and relied on limited data in terms of geographic regions and the type of medical institutions. This study utilized nationwide data covering 8 types of medical institutions. We obtained data from Health Insurance Review and Assessment Service and National Population and Housing Census. The correlation coefficients of resident, daytime, university-graduate population, and the population of different age groups (fewer than 15, 15~64, 65 or more) were compared to understand their relative association with the location of medical institutions. Medical clinic, dental clinic, oriental medical clinic, and pharmacy, all of which are almost completely operated by private sector, showed strong positive correlation with population. Hospital-level medical institutions, which are operated by both public and private sector, had moderate positive correlation. Daytime population and university-graduate population, rather than resident population, were more correlated with the location of medical clinics. The correlation coefficients of the population of 15~64 age group and the location of medical institutions were greater than that of other age groups. The results showed that daytime and university-graduate population are more important than resident population to explain the location of medicalrelated facilities. The results also suggests that the population of age groups (especially, 15~64) might be one of important influence factors in the location of medical institutions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.99-114
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• 2012

Proxy Mobile IPv6 (PMIPv6) has received considerable attention between telecommunications and the Internet communities and does not require active participation of the Mobile Node (MN) by way of network-based mobility management. The PMIPv6 domain is studying establishment in progress to support extensively a number of MN by using a low handover latency. In this research, we are propose a novel 3S scheme for building Scalable and Secure and Seamless PMIPv6 domains. In the proposed scheme, all of Mobility Access Gateway (MAG) are acting as the Local Mobility Anchor (LMA) and composing a virtual ring with another MAG. General hashing is used in the efficient distribution-mapping between each MN and the MN's LMA of all MAGs. And, MAG and MN are authenticated using the symmetric key. Through mathematical analysis, we verifies the safety, scalability, and seamless service for 3S. Also, we're propose a handover procedure of 3S and show better than the existing schemes in terms of handover latency.

• Journal of Korean Academy of Nursing
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• v.2 no.1
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• pp.159-174
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• 1971

The Family Planning Program has teen intensively implemented in Korea by the national policy since 1962. However, the desired effective results were not fully obtained by many reasons such as the shortage of qualified workers, lack of eligible women's cooperation and understanding of the importance of family planning etc., The field family planning workers is classified into two categories along the governmental personnel order; the senior field worker and the assistant field worker. The former is qualified licensed nurse and the latter same as the former of a certified nurses-aid. These family planning worker's roles are somewhat in change not only in field education, distribution of contraceptions, administrating mother's class of assistant field workers but also responsible for the senior field workers such as recording, reporting and keeping statistics. Therefor, the desired success of family planning programming in Korea depends on family planning worker's professional abilities and activities in the field. In aiming to study on professional knowledge of the above two kinds of family planning workers, the following results were obtained through a field survey with question airs done as of October, 1970 in Kyonggi-Do. 1. Working term of the family planning workers in average were less than two years. The younger the assistant Field workers were, the earlier they left job. 2. The assistant field workers selected their job in order to the superficial rather than implementing job itself. 3. Most of the workers either in the health center or in the Up-Myun had a better understanding concerning with their job ; contraceptive methods, maintenance of equipment and drug keeping, and other administrative procedures, etc., 4. They had relatively better understanding and sufficient knowledge about contraception itself and application of it's methods and side effects in detail too, but less knowledges for the care after. 5. It was hard to Find out any differences in administrative knowledge and demographic understanding. 5. It is fully agreed upon that the longer the worker have experienced with the program, the more skilful she applied. 7. The worker who had training whether pre-service or insertive are working more effectively than the untrained. 8. The fundamental demographic knowledge is recommended to obtain for the workers in Kyonggi-Do.