• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.812-814
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• 1993

During the last two decades, we experienced a few of the energy shocks and felt the importance of the energy saving seriously. As our energy reliance on other countries is absolute. We must counter these situations nationally. To save the electric energy, various methods are explored such as the moderation of motor capability, the use of high efficiency system, the supervision of lighting systems, demand monitoring control systems. In this study, we develop a system for electric power energy saving. In Case the receiving point voltage is higher than the required voltage, the system reduce the voltage to an allowable level and by doing so it saves energy and protects the equipments from over voltage.

• CRM연구
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• v.4 no.2
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• pp.19-29
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• 2011

There is a large difference between purchasing patterns in an online shopping mall and in an offline market. This difference may be caused mainly by the difference in accessibility of online and offline markets. It means that an interval between the initial purchasing decision and its realization appears to be relatively short in an online shopping mall, because a customer can make an order immediately. Because of the short interval between a purchasing decision and its realization, an online shopping mall transaction usually contains fewer items than that of an offline market. In an offline market, customers usually keep some items in mind and buy them all at once a few days after deciding to buy them, instead of buying each item individually and immediately. On the contrary, more than 70% of online shopping mall transactions contain only one item. This statistic implies that traditional data mining techniques cannot be directly applied to online market analysis, because hardly any association rules can survive with an acceptable level of Support because of too many Null Transactions. Most market basket analyses on online shopping mall transactions, therefore, have been performed by expanding the co-occurrence criteria of traditional association rule mining. While the traditional co-occurrence criteria defines items purchased in one transaction as concurrently purchased items, the expanded co-occurrence criteria regards items purchased by a customer during some predefined period (e.g., a day) as concurrently purchased items. In studies using expanded co-occurrence criteria, however, the criteria has been defined arbitrarily by researchers without any theoretical grounds or agreement. The lack of clear grounds of adopting a certain co-occurrence criteria degrades the reliability of the analytical results. Moreover, it is hard to derive new meaningful findings by combining the outcomes of previous individual studies. In this paper, we attempt to compare expanded co-occurrence criteria and propose a guideline for selecting an appropriate one. First of all, we compare the accuracy of association rules discovered according to various co-occurrence criteria. By doing this experiment we expect that we can provide a guideline for selecting appropriate co-occurrence criteria that corresponds to the purpose of the analysis. Additionally, we will perform similar experiments with several groups of customers that are segmented by each customer's average duration between orders. By this experiment, we attempt to discover the relationship between the optimal co-occurrence criteria and the customer's average duration between orders. Finally, by a series of experiments, we expect that we can provide basic guidelines for developing customized recommendation systems.

• Journal of International Area Studies (JIAS)
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• v.19 no.1
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• pp.157-204
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• 2015

This paper explores firm-specific internal and external determinants of the sustainability of "the social innovative enterprise(SIE)" by conducting a case research on Fragrant People Co. In doing so, some business and policy implications have been produced concerning the components and determinants of the sustainability of the SIE. First, entrepreneurship is a necessary factor for the survival and growth of the SIE. A social entrepreneur does manage effectively social and economic opportunities for making economic and social values interact dynamically beyond their trade-off relationship and creating new market chances. Second, the SIE also needs competitive advantages as commercial enterprises do. Valuable resources to be used for taking opportunities and avoiding threats, rare resources not to be possessed by other firms, and resources not to be easily imitated by competitors are extremely necessary for achieving objectives of the SIE. In addition, a firm must be well organized for those valuable, rare, and not easily imitated resources. Economic performance achieved by the SIE gives a birth to its financial independence, contributing to the realization of symmetric social performance. Third, the SIEs will be allowed to seek symmetrically economic and social performance only when they use sufficiently competitive advantage resources with entrepreneurship, which is composed of innovativeness, proactiveness, agility and risk-taking attitudes. In doing so, financial assistance from central or local governments may not ensure the sustainability of the SIEs. In addition, vision & value sharing(person-organization fit) can ensure the sustainability of the SIEs only when it is connected with the organizational commitment.

• Journal of the Korean Society for information Management
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• v.34 no.4
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• pp.101-126
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• 2017

Data Science is emerging as a closely related field of study to Library and Information Science (LIS), and as an interdisciplinary subject combining LIS, statistics and computer science in an attempt to understand the value of data by applying what LIS has been doing for collecting, storing, organizing, analyzing, and utilizing information. To investigate which subject fields other than LIS, statistics, and computer science are related to Data Science, this study retrieved 667 materials from Web of Science Core Collection, extracted terms representing Web of Science Categories, examined subject fields that are studying Data Science using descriptive analysis, analyzed the intellectual structure of the field by co-word analysis and network analysis, and visualized the results as a Pathfinder network with clustering created with the PNNC clustering algorithm. The result of this study might help to understand the intellectual structure of the Data Science field, and may be helpful to give an idea for developing relatively new curriculum.

• Journal of Chest Surgery
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• v.49 no.2
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• pp.107-111
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• 2016

Hypoplastic left heart complex (HLHC) consists of less severe underdevelopment of the left ventricle without intrinsic left valvular stenosis, i.e., a subset of hypoplastic left heart syndrome (HLHS). HLHC patients may be able to undergo biventricular repair, while HLHS requires single ventricle palliation (or transplant). However, there is no consensus regarding the likelihood of favorable outcomes in neonates with HLHC selected to undergo this surgical approach. This case report describes a neonate with HLHC, co-arctation of the aorta (CoA), and patent ductus arteriosus (PDA) who was initially palliated using bilateral pulmonary artery banding due to unstable ductus-dependent circulation. A postoperative echocardiogram showed newly appearing CoA and progressively narrowing PDA, which resulted in the need for biventricular repair 21 days following the palliation surgery. The patient was discharged on postoperative day 13 without complications and is doing clinically well seven months after surgery.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.727-736
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• 2019

In this paper, we present how to create a point cloud for a target area using multiple unmanned aerial vehicle images and to remove the gaps and overlapping points between datasets. For this purpose, first, IBA (Incremental Bundle Adjustment) technique was applied to correct the position and attitude of UAV platform. We generate a point cloud by using MDR (Multi-Dimensional Relaxation) matching technique. Next, we register point clouds based on observation vectors between stereo images by doing this we remove gaps between point clouds which are generated from different stereo pairs. Finally, we applied an occupancy grids based integration algorithm to remove duplicated points to create an integrated point cloud. The experiments were performed using UAV images, and our experiments show that it is possible to remove gaps and duplicate points between point clouds generated from different stereo pairs.

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.591-599
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• 1996

This study was undertaken to investigate the cytotoxicity of orthodontic wires after doing various treatments to the wires. 018x025 inch Stainless steel(A) and Co-Cr(B) wires were used and each of them were divided into 4 groups. A-1 and B-1 groups were as received state, and A-2 and B-2 groups were heat treated. A-3 and B-3 groups were electropolished after heat treatment, and A-4 and B-4 groups were soldered with Ag-solder. Each group had 3 wires and these were sterilized with Ethylene Oxide gas. We used human gingival fibroblast cell culture and agar overlay technique to investigate the cytotoxicity of each group of wires. The cytotoxicity of wire was assessed using reaction index (zone index/lysis index). The findings of this study were as follows. 1. Both of the stainless steel wire and Co-Cr wire showed no cytotoxicity in as received state. 2. Heat treatment or electropolishing of the wires had no effect on the cytotoxicity of the wires 3. Soldered stainless steel wires showed a little wider zone of discoloration than soldered Co-Cr wires, but the zone index and cytotoxicity(reaction index) was not different. 4. Soldered wires showed moderate cytotoxicity in both of the wires.

• Journal of the Korean Electrochemical Society
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• v.16 no.3
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• pp.169-176
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• 2013

Solid state lithium oxide compounds of layered structure, which has high stability of structure, are mainly used as the cathode materials in lithium-ion batteries (LIBs). Recently, the investigation of Solid Electrolyte Interphase (SEI) between active materials and electrolyte has been focusing to improve the performance of lithium-ion batteries. For the investigation of the SEI, the study of surface properties of cathode materials and anode materials is also required in advance. $LiNiO_2$ and $LiCoO_2$ are very similar layered structure of cathode active materials and representative solid state lithium oxide compounds in LIBs. Various experimental and theoretical studies have been doing for $LiCoO_2$. The theoretical investigation of $LiNiO_2$ is not sufficient, however, even if experimental studies of $LiNiO_2$ are enough. In this study, the surface energies of nine facets of $LiNiO_2$ crystal facets were calculated by Density Functional Theory. In XRD data of $LiNiO_2$, (003), (104), (101), et al. facets are main surfaces in order. However, the results of calculation are different with XRD data. Thus, both (104) and (101) facets, which are energetically stable and measured in XRD, are mainly exposed in the surface of $LiNiO_2$ and it is expected that intercalation and de-intercalation of Li-ion will be affected by them.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.507-511
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• 1995

In an attempt to improve the productivity of ${\beta}-galactosidase$ from Bacillus sp. A1, which was isolated from soil and has remarkably higher transgalactosylation activity than lactose hydrolysis activity, a chemical mutation procedure using N-methyl-N'-nitro-N-nitrosoguanidine followed by selection was conducted. The final selection, designated as Bacillus sp. A4442, turned out to show a substantially increased enzyme productivity. Catabolite repression by glucose and lactose requirement as an inducer for the enzyme biosynthesis, which were shown in the parent strain, was markedly diminished; instead it was found out that galactose acts as another inducer. Because pH of medium, one of the most important factors for cell growth as well as enzyme production, is closely related with the sugar concentration during culture, it was kept in the optimum range of $6.5{\sim}7.5$; for this the initial glucose concentration was adjusted to be 0.5% which was thereafter maintained by the controlled pumping-in of lactose using the pH-stat technique. By doing so, we were able to increase the productivity of ${\beta}-galactosidase$ with high transgalactosylation activity up to $44\;unit/m{\ell}-broth$.

• Journal of the Korea Society of Computer and Information
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• v.29 no.6
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• pp.121-130
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• 2024

In this paper, we propose and design an NCS-based job matching system for individuals with disabilities. This system allows users with disabilities to access it, input basic information (personal and disability-related details), and take a simple test related to job performance. The system then provides NCS job-related information appropriate to their type and degree of disability. To effectively link various NCS-based jobs, it is essential to consider the degree of disability for each type of disability. However, most evaluation tools target specific types of disabilities or assess the vocational abilities of individuals with disabilities in a limited manner, focusing only on cognitive levels or certain physical functions. This makes it challenging to apply these tools to an NCS-based job matching system for individuals with disabilities. Therefore, in this paper, we utilize the ICF coresets for VR to assess the cognitive levels or physical functions required for performing specific jobs. Additionally, we use the NCS vocational competency evaluation tools to determine the levels of vocational competencies required for performing specific jobs. By doing so, we match NCS-based jobs according to the type and degree of disability. The proposed NCS-based job matching system relies on the user's interaction with the system, which may pose challenges for visually impaired individuals or those with intellectual and autism spectrum disabilities who have low literacy levels. Enhancing the accessibility of this system could enable individuals with disabilities to receive recommendations for NCS-based jobs that suit their vocational abilities.