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An Epidemiologic Study on Related Factors to HBsAg and Anti-HBs (B형 바이러스 간염의 검사성적 및 관련요인에 관한 역학적 연구 -의료직을 포함한 직장인을 중심으로-)

  • Kim, Joo-Ja;Han, Gu-Woong;Nam, Taik-Sung
    • Journal of Preventive Medicine and Public Health
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    • v.19 no.1 s.19
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    • pp.91-99
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    • 1986
  • To determine relationships of supposed risk factors to positives for HBsAg and Anti-HBs and also relationships of subjective symptoms to positives for HBsAg and Anti-HBs, study of 658 people working in the hospital, university, bank and other office was performed. Positive rate for HBsAg was about 7.9% and positive rate for Anti-HBs was about 20.0%. Odds ratio of HBsAg was high and significant in individuals who are married and who have previous hepatitis B(P<0.001), medical personnel in family, more than 4 people in a room(0.01

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The Determinants of Blockholder Presence: Evidence from Korea

  • KIM, Hung Sik;CHO, Kyung-Shick
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.4
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    • pp.29-39
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    • 2020
  • The purpose of this study is to investigate the determinants of blockholder presence in the Korean stock market. This study examines previous theories and studies, points that previous studies did not examine, and proposes two hypotheses. To verify two hypotheses, fundamental data were collected from firms listed on Korea Exchange from 2005 to 2017. As explanatory variables, we use the factors and characteristics of the firms used in the previous studies. Logistic regression analysis was conducted to test the determinants of blockholder presence. We find that firm size is the most distinctive factor determining the presence of blockholder, and firm idiosyncratic risk is the most similar factor determining the existence of each blockholder. Tobin Q shows significant value in family and government, and R&D intensity appears to be a negative related to the presence of blockholder in financial institutions. We also find that the determinant of blockholder presence differs from the mechanisms that govern each individual blockholder type when all blockholders grouped together. This suggests that there is blockholder heterogeneity within Korea listing firms. Our findings contribute to investors and policy makers who interested in the determinants of the presence of blockholder and blockhoder heterogeneity in Korea stock market.

A Study on Multi-Media Contents Security using Smart Phone (스마트 폰을 이용한 멀티미디어 콘텐츠 보안에 관한 연구)

  • Kim, Dong-Ryool;Han, Kun-Hee
    • Journal of Digital Convergence
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    • v.11 no.11
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    • pp.675-682
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    • 2013
  • This paper tries to solve the problems which previous methods have the model using smart card for protecting digital contents. This study provides a contents distribution model to protect the rights of author, distributor, and user as well as user's information by using technologies such as cryptography, DRM(Digital Right Management), access control, etc. The proposed system is evaluated as the most safety model compared with previous methods because it not only solves the problems which the previous methods have, but also protects four type of risks such as use of contents which other mobile devices download, the attack on the key to decode the message, the attack on leaking the contents, and the internal attack such as an illegal reproduction.

Yielding Behavior of Compacted Decomposed Granitic Soil under Anisotropic Compression Previous Loading (비등방 압축의 선행재하를 받은 다짐풍화화강토의 항복거동)

  • Jeong, Sang-Guk;Kang, Kwon-Soo;Yang, Jae-Hyouk
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.3
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    • pp.233-244
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    • 2001
  • Stress-strain behaviour of soil varies based on stress path and stress history. There has been few study on the characteristics of yielding curve which has anisotropic compression stress history in decomposed granite soil. During this study, various stress path tests in previous anisotropic compression stress history are performed on compacted decomposed granite soil sampled at Iksan, Chonbuk. Yielding points are determined from various stress-strain curves (${\eta}-{\varepsilon}$, ${\eta}$-v, and ${\eta}$-k, ${\eta}$-W curves). Stress-strain curve is certified which shows yielding point very clearly. The shape and characteristics of anisotropic compression yielding curves are examined. The main results are summarized as follows : 1) p' constant and compressive direction in stress paths, which has experienced previous anisotropic compression stress history, shows relatively dear yielding points. 2) Yielding curves defined from ${\eta}$-k and ${\eta}$-W curve show almost perfect ellipse. 3) Directions of plastic strain incremental vector($dv^p/d{\varepsilon}^p$) are not perpendicular to yielding curve.

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NMDA Receptor Antagonists Enhance 5-HT2 Receptor-Mediated Behavior, Head-Twitch Response, in PCPA-Treated Mice

  • Kim, Hack-Seang;Park, In-Sook;Lim, Hwa-Kyung;Choi, Hong-Seork
    • Archives of Pharmacal Research
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    • v.22 no.2
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    • pp.113-118
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    • 1999
  • Previous work in our laboratory has shown that the N-methyl-D-aspartate (NMDA) receptor antagonists, AP-5, CPP, MK-801, ketamine, dextrorphan and dextromethorphan cause a pronounced enhancement of 5-hydroxytryptamine (5-HT)-induced head-twitch response (HTR) in intact mice, suggesting the involvement of NMDA receptors in the glutamatergic modulation of serotonergic function at the postsynaptic $5-HT_{2}$ receptors. The purpose of this study was to extend our previous work on the behavioral interaction between glutamatergic and serotonergic receptors. In the present study, both competitive (AP-5 and CPP) and noncompeti-tive (MI-801, ketamine, dextrorphan and dextromethorphan) NMDA receptor antagonists markedly enhanced 5-HT-induced selective serotonergic behavior, HTR, in p-chlorophenylalanine (PCPA)-treated mice which were devoid of any involvement of indirect serotonergic function, to establish the involvement of the NMDA receptor in 5-HT-induced HTR at the postsyaptic $5-HT_{2}$receptors. In addition, the enhancement of 5-HT-induced HTR was inhibited by a dopamine agonist, apomorphine, NMDA receptor antagonist, NMDA and a serotonin $5-HT_{2}$receptor antagonist, cyproheptadine, in PCPA-treated mice. Therefore, the present results support our previous conclusion that the NMDA receptors play an important role in the glutamatergic modulation of serotonergic function at the poststynaptic $5-HT_{2}$ receptors.

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A Development of Optimal Travel Course Recommendation System based on Altered TSP and Elasticsearch Algorithm (변형된 TSP 및 엘라스틱서치 알고리즘 기반의 최적 여행지 코스 추천 시스템 개발)

  • Kim, Jun-Yeong;Jo, Kyeong-Ho;Park, Jun;Jung, Se-Hoon;Sim, Chun-Bo
    • Journal of Korea Multimedia Society
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    • v.22 no.9
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    • pp.1108-1121
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    • 2019
  • As the quality and level of life rise, many people are doing search for various pieces of information about tourism. In addition, users prefer the search methods reflecting individual opinions such as SNS and blogs to the official websites of tourist destination. Many of previous studies focused on a recommendation system for tourist courses based on the GPS information and past travel records of users, but such a system was not capable of recommending the latest tourist trends. This study thus set out to collect and analyze the latest SNS data to recommend tourist destination of high interest among users. It also aimed to propose an altered TSP algorithm to recommend the optimal routes to the recommended destination within an area and a system to recommend the optimal tourist courses by applying the Elasticsearch engine. The altered TSP algorithm proposed in the study used the location information of users instead of Dijkstra's algorithm technique used in previous studies to select a certain tourist destination and allowed users to check the recommended courses for the entire tourist destination within an area, thus offering more diverse tourist destination recommendations than previous studies.

The Role of Corporate Social Responsibility on the Relationship between Financial Performance and Company Value

  • UTAMI, Elok Sri;HASAN, Muhamad
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.1249-1256
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    • 2021
  • This study investigates the company value determinant by observing the effect of financial performance and Corporate Social Responsibility (CSR) and its role in moderating performance achievement. The macro-economy variables such as inflation and interest rate are also used as the controlling variable. This research employs the sample of manufacturing companies of the food and beverage sub-sector listed on the Indonesia Stock Exchange. This study used panel data from 2013 to 2017, with the moderating regression analysis. The result shows that the profitability of the current or previous period affects the company's value. CSR and company size affect the company value at the next period shows that stock price, which reflects the investor's perception today, will be affected by the CSR, Size, and Return On Asset of the previous year. CSR also shows that it can be the substitute for profitability since a company that performs CSR is the one that has a good performance. The regression moderating model and the profitability of the previous period have a higher explanatory power than the higher R square value in explaining company value.

A Study on the Current Status of Supply Chain Risks after COVID-19: Focusing on Network Analysis (코로나19 이후 공급사슬 리스크에 대한 현황연구: 네트워크 분석을 중심으로)

  • EuiBeom Jeong;Keontaek Oh
    • Journal of Korea Society of Industrial Information Systems
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    • v.28 no.4
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    • pp.77-92
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    • 2023
  • In this study, keyword network analysis was performed based on global and domestic journals, and network text analysis was conducted for news and articles to examine major issues and research trends on supply chain risks after COVID-19. As a result of analyzing the supply chain risk, after COVID-19 which was relatively insufficient in previous studies, research trends and topics such as supply chain risk recovery, response and public welfare, which are different from previous previous studies, were found in global and domestic journals, news and articles and it was possible to suggest practical strategies and insights for supply chain risk strategies for firms.

Experimental study on single- and two-phase flow behaviors within porous particle beds

  • Jong Seok Oh;Sang Mo An;Hwan Yeol Kim;Dong Eok Kim
    • Nuclear Engineering and Technology
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    • v.55 no.3
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    • pp.1105-1117
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    • 2023
  • In this study, the pressure drop behavior of single- and two-phase flows of air and water through the porous beds filled with uniform and non-uniform sized spherical particles was examined. The pressure drop data in the single-phase flow experiments for the uniform particle beds agreed well with the original Ergun correlation. The results from the two-phase flow experiments were analyzed using numerical results based on three types of previous models. In the experiments for the uniform particle beds, the data on the two-phase pressure drop clearly showed the effect of the flow regime transition with a variation in the gas flow rate under stagnant liquid condition. The numerical analyses indicated that the predictability of the previous models for the experimental data relied mainly on the sub-models of the flow regime transitions and interfacial drag. In the experiments for the non-uniform particle beds, the two-phase pressure loss could be predicted well with numerical calculations based on the effective particle diameter. However, the previous models failed to accurately predict the counter-current flooding limit observed in the experiments. Finally, we propose a relation of falling liquid velocity into the particle bed by gravity to appropriately simulate the CCFL phenomenon.

Effect of prior cesarean delivery on the outcomes of intracytoplasmic sperm injection

  • Suzan Atteya Gewida;Mohamed Salah Eldeen Abd Rabbo;Mohammed Abd Elmoety El Samra;Hesham Mahmoud Adel Abdel Moneim
    • Clinical and Experimental Reproductive Medicine
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    • v.51 no.1
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    • pp.63-68
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    • 2024
  • Objective: This study was conducted to investigate the impact of previous delivery mode on pregnancy outcomes in patients with secondary infertility after frozen-thawed embryo transfer. Methods: This prospective observational study included 140 patients experiencing secondary infertility. Of these, 70 patients had a previous cesarean delivery (CD), while the remaining 70 patients had a previous normal vaginal delivery (NVD). The primary outcome was the implantation rate. The secondary outcomes included rates of clinical pregnancy, chemical pregnancy, miscarriage, and ectopic pregnancy. Results: The comparison of all fertility outcomes between the two groups revealed no statistically significant differences. The implantation rate was 40.4% in the CD group and 41.7% in the NVD group (p=0.842). The clinical pregnancy rate was 50% in the CD group and 49.3% in the NVD group (p=0.932), while the chemical pregnancy rate was 14.6% in the CD group and 19% in the NVD group (p=0.591). The miscarriage rates in the CD and NVD groups were 20% and 17.6%, respectively (p=0.803). One case of tubal ectopic pregnancy occurred in the NVD group (1.4%). Conclusion: The mode of prior delivery did not significantly impact pregnancy outcomes following frozen-thawed embryo transfer.