• Elastomers and Composites
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• v.44 no.3
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• pp.299-307
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• 2009

The effects of reinforcing materials on durability and mechanical properties of V-rib belt were investigated. Cotton fiber and ZnO were used as a filler for CR, and cotton and aramid fiber were used for EPDM rubber compounds. These materials were prepared as a specimen and V-rib belt for heat resistant and mechanical test. High contents of ZnO give improved wear resistance, and higher contents of cotton fiber showed higher durability in high rotation speed but lower wear resistance for CR rubber compounds. Using the aramid and cotton fiber together in EPDM rubber compounds, thermal and wear resistance were improved simultaneously. The material containing EPDM matrix showed better durability and wear resistance than those of containing CR matrix comparing in the same cotton fiber contents.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.12 no.1
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• pp.25-30
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• 1976

In the area of the Far East Asia, cyclones are observed 157ea in winter season during the years(1966-1974). Some of them are most difficult to be forecasted due to the extreme irregulalities, have carried out synoptic analysis. The rapid development of cyclones can be attributed to the descending of cold air mass surrounding the axis of the Jet Stream due to the cyclonic rotation, and the lowering of the Jet axis. The Relationships between upper trough line and max. (or min) axis of upper air temperature on the 700mb contributes to the development of the cyclones.

• Proceedings of the Korean Association for Survey Research Conference
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• 2003.06a
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• pp.140-160
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• 2003

The purpose of this study is to identify and evaluate the competitiveness of ports in ASEAN(Association of Southeast Asian Nations), which plays a leading role in basing the hub of international logistics strategies as a countermeasure in changes of international logistics environments. This region represents most severe competition among Mega hub ports in the world in terms of container cargo throughput at the onset of the 21st century. The research method in this study accounted for over lapping between attributes, and introduced the HFP method that can perform mathematical operations. The scope of this study was strictly confined to the ports of ASEAN, which cover the top 100 of 350 container ports that were presented in Containerization International Yearbook 2002 wi th reference to container throughput. The results of this study show Singapore in the number one position. Even compared with major ports in Korea (after getting comparative ratings and applying tile same data and evaluation structure), the number one position still goes to Singapore and then Busan(2) and Manila(2), followed by Port Klang(4), Tanjung Priok(5), Tanjung Perak(6), Bangkok(7), Inchon(8), Laem Chabang(9) and Penang(9). In terms of the main contributions of this study, it is the first empirical study to apply the combined at tributes of detailed and representative attributes into the advanced HFP model which was enhanced by the KJ method to evaluate the port competitiveness in ASEAN. Up-to-now, none have comprehensively conducted researches with sophisticated port methodology that has discussed a variety of changes in port development and terminal transfers of major shipping lines. Moreover, through the comparative evaluation among major ports in Korea and ASEAN, the presentation of comparative competitiveness for Korean ports is a great achievement in this study. In order to reinforce this study, it needs further compensative research, including cost factors which could not be applied to modeling the subject ports by lack of consistently qualified data in ASEAN.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.79-89
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• 1999

The purpose of this study is to compare health status and activities for the pain and no-pain groups in the elderly. The study subjects included 189 elderly people(65 years and older) living in an urban area. They were surveyed at their homes through interview using a closed-ended questionnaire from Nov. 6th. to Nov. 16th. 1997. The instrument used in the study was selected after carefully reviewing pain-related articles and records well described the characteristics of the elderly. The data were analysed by using descriptive statistics and chi-square tests. The findings were as follows : Of the 189 subjects, 83.6% reported experiencing the pain for the last year. By the age, there were significant differences between the pain and no-pain group(${\chi}^2$=9.572, p=.023). The percentage of the pain complainers was the highest in 80 years and older(100.0%), followed by 70~74(89.1%), 75~79(81.3%), 65~69(76.8%) which presented crude increase according to age. By sex, men had lower pain prevalence(69.5%) than that of women(90.0%). The number of pain complainers was higher in women than men(${\chi}^2$=12.448, p=.023). There were significant differences between the pain and no-pain groups by spouse distribution(${\chi}^2$=10.736, p=.001), educational state(${\chi}^2$=13.020, p=.000), occupation(${\chi}^2$=18.807, p=.000). Pain prevalence in the subjects having no spouse(59.3%) was higher than those having spouse(40.7%), Illiteracy rate was higher in pain group(49.0%) than no-pain group(13.3%). The number of the subjects having occupation(full time or part time) was fewer in pain group than no-pain group. By health status, there were significant differences between two groups(${\chi}^2$=40.055, p=.000). : the pain group showed poor(61.4%), followed by moderate(22.1%), good(16.5%) while no-pain group showed good(64.5%), moderate(29.0%), poor(6.5%). By activities, there were significant differences between the pain and no-pain groups. The pain group was disturbed more severely than the no-pain group in movement(${\chi}^2$=57.829, p=.000), sleep(${\chi}^2$=12.785, p=.000), usual activities(${\chi}^2$=39.196, p=.000), receiving guests(${\chi}^2$=13.163, p=.000), and hobbies and recreation(${\chi}^2$=28.177, p=.000).

• Polymer(Korea)
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• v.25 no.1
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• pp.71-77
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• 2001

Unsaturated polyester(UP) resin is one of the major thermosetting resins. It is very useful as the matrix resin of the composite material because of its low viscosity. The polymer resin, however, has several drawbacks; The volume shrinkage occurs during the crosslinking reaction of the UP resin with styrene monomer and the resulting polymer is weak to the alkali and also brittle. The mechanical properties of UP resin can be improved by blending various materials. In this study, polyurethane(PU) was used as a modifier in order to enhance the toughness of the UP resin. The goal of the research is to study the effect of the polyol molecular weight as a PU soft segment and the PU contents on the toughness of PU-modified UP resins. UP/PU polymer network may occur through the reaction between isocyanate group in the methyldiisocyanate(MDI) and hydroxyl group in the UP molecules. The maximum toughness value was shown at 2 wt% of the PU content. This effect results from the incorporation of the PU segment into the UP resin.

• Journal of Service Research and Studies
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• v.10 no.1
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• pp.55-67
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• 2020

Fine dust has recently become one of the greatest concerns of Korean people and has been a target of considerable efforts by governments and local governments. In the academic world, many researches have been carried out in relation to fine dust, but the research on the economic field has been relatively few. So we wanted to know how fine dust affects the economy. Big data of PM10 concentration for fine dust and fine dust theme stock price were collected for five years from 2013 to 2017. Regression analysis was performed using the linear regression model, the generalized least squares method. As a result, the change in the fine dust concentration was found to have a effect on the related theme stocks' price. When the fine dust concentration increased compared to the previous day, the fine dust theme stocks' price also showed a tendency to increase. Also, according to the analysis of stock price change from 2013 to 2017 based on fine dust theme stocks, companies with large regression coefficients were changed every year. Among them, the regression coefficients of Monalisa were repeatedly high in 2014, 2015, 2017, Samil Pharmaceutical in 2015, 2016 and 2017, and Welcron in 2016 and 2017, and the companies were judged to be sensitive to the concentration of fine dust. The companies that responded the most in the past 5 years were Wokong, Welcron, Dongsung Pharmaceutical, Samil Pharmaceutical, and Monalisa. If PM2.5 measurement data are accumulated enough, it would be meaningful to compare and analyze PM2.5 concentration with independent variables. In this study, only the fine dust concentration is used as an independent variable. However, it is expected that a more clear and well-explained result can be found by adding appropriate additional variables to increase the explanatory power.

• Journal of the Korea Society for Simulation
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• v.25 no.1
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• pp.21-28
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• 2016

ROK armed forces conducted exercise for something limited "Civil Factor" of Civil-Military Operations at the Liberalized Area in North Korea by using ROK battle simulation model and a linked US simulation model such as JNEM during ROK-US combined exercise period. However, they conducted exercise by exchanging with messages only during each exercise, because of hard coding for "Civil-Factor" and various situations applied onto battle simulation model and JNEM. Fortunately, ROK armed forces arranged the 5 functionalities of Civil-Military Operations which is adopted with military situation in Korean Peninsular. Even more "Civil-Military Operations Simulation Model System" is developing since 2014 by ROK MND. Among the 5 functionalities of Civil-Military Operations, the administration is fundamental. Its detailed operational plan is hard to be quantitative subjects because it is too qualitative to be simulated. But we found a way to quantify, and described simulation flow charts for the 5 main subjects (including 13 tasks) of administration to verify relevance between its simulation results and other functionalities. So we suggested a simulation method which gets an objective suitability, also hope this will be helpful to the Civil-Military Operations exercise.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.69-74
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• 2007

This study was performed to determine the estrous cycles by macroscopic observation of the ovarian changes using the laparoscopy and to make use of these results for embryo transfer in Korean black goat (Copra hircus aegagrus). Laparoscopic examinations of the ovaries were performed from 2 days after $CIDR^(R)$ removal to 22 days after ovulation. The serial morphological changes of follicles and corpus luteum (CL) were observed. CL was classified corpus hemorrhagicum(CH), corpus luteum (CL) and corpus albicans (CA) by its maturation and regression. On the day before ovulation (Day 0), Graafian follicles (GF) were found on one or both ovaries. On the day (Day 1) and $2^{nd}$day (Day 2) of ovulation, and ovulation depression (OD) and an early stage corpus hemorrhagicum $(CH_1)$ were observed at the site of GF, respectively. On Days 3 to 4, more developed and enlarged corpus hemorrhagicum $(CH_2\;and\;CH_3)$ arised from the ovulation of the GF with well vascularization. On Days 5 to 6, it was identified that mature corpus luteum $(CL_3)$ was grown on the ovary, and fully developed CL with adjacent follicles were occupied most part of the ovary on Days 17 and 18. Then the size of CL was diminished, and completely luteal regression $(CL_1\;or\;CA)$ with new large follicle was identified on Days 20 and 22. From these results, the 4 stages of the estrous cycle in Korean black goats were 1) estrus (Day 0) for 1 day, 2) metestrus $(Day\;1{\sim}4)$ for 4 days (stage of CH development), 3) diestrus $(Day\;5{\sim}16/17)$ for 12 or 13 days (luteal stage), and 4) proestrus $(Day\;17/18{\sim}20/22)$ for 4 or 5 days (stage of luteal regression and follicular growing). Laparoscopy for observation of ovarian changes was invasive than laparotomy. Additionally, it had advantages of reduced adhesion and quick operation time. It was considered that laparoscopic examination of ovarian changes will be useful for embryo transfer in the Korean black goats.

• KOREAN POULTRY JOURNAL
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• v.4 no.10 s.36
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• pp.34-46
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• 1972

1. 육추율 육성율 성계생존율 육추율 99.7$\%$는 1회 98.5$\%$, 2회 99.2$\%$, 3회 99.8$\%$, 4회 98.3$\%$ 5회 98.7$\%$와 근사하다. 육성율 평균 87.1$\%$는 1회 97.5$\%$, 2회 97.2$\%$, 3회 96.6$\%$, 4회 97.9$\%$에 비하여 10$\%$정도 낮으며 5회 89.7$\%$보다도 2.6$\%$ 낮은데 이는 근년 많이 발생하는 마렉병 및 백혈병이 주원인이며,(7회 검정계 부터 마렉병 예방접종)현 김포검정사 신축이 장마로 인하여 지연되므로서 더욱 임시육추사에서의 육성기간에 스트레스를 받았기 때문이며 성계생존율은 평균 75.3$\%$이며, 1회 80.3$\%$, 2회 84.8$\%$, 3회 71.8$\%$, 4회 87.3$\%$, 5회 71.4$\%$ 이었다. 이를 폐사원인별로 보면 세균성 질환으로 인한 폐사가 전체폐사수의 8.9$\%$ 병독(마렉병 및 백혈병)이 61.5$\%$원충 0.7$\%$ 대사장애 9.2$\%$ 생식기장애 3.4$\%$ 내장파열(간파열 탈항등) 5.7$\%$ 곰팡이 1.1$\%$ 기타(복막염 장염등) 9.5$\%$로 마렉병 및 백혈병이 주인이며 이를 검정각회별로 보면 1.2회 32.3$\%$, 3회 43.3$\%$, 4회 41.3$\%$, 5회 56.2$\%$, 6회 61.5$\%$로 매년 증가하고 있다. 2. 성성숙일령 전체평균 155.9일로 가장 빠른 구는 4구의 144일이고 가장 늦은 구는 23구의 166일이며 1일 189.2일, 2회 181.2일 보다 30일 정도 빨라진 것은 1.2회 검정은 산란율 50$\%$ 연2일 산란한 전일로 계산하였으며 3회 검정부터는 산란율 50$\%$에 달한 일령으로 계산하였기 때문이다. 3. 산란율 산란지수 산란율 평균 64.6$\%$이고 최상위구는 77.1$\%$, 최하위구는 52.8$\%$이며 유색품종 평균산란율은 58.4$\%$ 백색품종은 66.6$\%$이며 성성숙일령이 빨라짐에 따라 전체산란율은 약간 떨어지고 있다. 산란지수-평균은 189.7개로 200개 이상 산란한 상위군이 모두 성계생존율이 높은 구임을 알 수 있다. 4. 사료요구율 전체평균 2.8로 1회 3.54, 2회 3.1., 3회 3.98 4회 2.87, 5회 2.83으로 점차 개선되어 가고 있으며 유색품종의 사료요구율 평균은 3.3이었다. 5. 난평균중량 평균 58.4g로 최상위구는 60.8g, 최하위구는 56.6g 이며 국산계의 평균난중은 57.9g 외국제 평균난중 58.6g이었다. 6. 체중 평균체중은 300일령 2,117.g, 500일령 2,207이며 유색품종은 300일령 2.6160g, 500일령 2.656.7g이었다. 7. 사료 섭취량 사료섭취량 평균은 1일수당 육추기 33.6g, 육성기 68.5g, 산란기 109.9g이었다. 8 경제성 총수입은 2,539,799 으로 전체수입의 85.3$\%$가 계란수입이고, 폐계 수입은 14.7$\%$이다. 지출은 총계 1,854.517원으로 전체 지출의 92.5$\%$가 사료비, 7.5$\%$가 초생추대이었다. 9. 후기 마렉병 백신이 71년 중반기부터 수입되므로써 마렉병 예방접종을 하지 못하므로서 전체 폐사 수의 61.5$\%$를 차지하는 많은 피해를 보았다.

• Radiation Oncology Journal
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• v.26 no.2
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• pp.104-112
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• 2008

Purpose: To assess the toxicity and tumor response induced by $DCVac/IR^{(R)}$ dendritic cell(DC) immunotherapy combined with irradiation for refractory colorectal cancer patients with multiple liver metastases. Materials and Methods: Between May 2004 and November 2006, applicants from a pool of refractory colorectal cancer patients with multiple liver metastases were enrolled. The patients were registered after having signed the informed consent form, which had been approved by the Institutional Review Board from the Dong-A University and Busan National University Hospital. DCs were obtained from peripheral blood of each patient, and then cultured in vitro. A total of $6{\times}10^6$ DCs were packed into a vial($DCVac/IR^{(R)}$, 0.5 ml) at the convenience of each patient's schedule. On the day before and on the day of each vaccination, each patient received a 4 Gy radiation dose to the target tumor. On the day of vaccination, the indicated dose of autologous DCs was injected into the irradiated tumor using ultrasound-guided needle injection procedures. A total of four vaccinations were scheduled at three 2-week intervals and one 4 week interval at the Dong-A University and Busan National University Hospital. If the tumor status was deemed to be stable or responding to therapy, an additional vaccination dose or two was approved at 4 week intervals beyond the fourth immunization. A tolerance test for DCs was conducted by injecting a range of doses($3{\times}10^6\;to\;12{\times}10^6$ DCs) after the 3rd injection. Moreover, the maximal tolerable dose was applied to additional patients. Treatment safety was evaluated in all patients who had at least one injection. Treatment feasibility was evaluated by the 10th week by assessing the response of patients having at least 4 injections. For systemic toxicities, the evaluation was performed using the National Cancer Institute Common Toxicity Criteria, whereas adverse effects were recorded using common WHO toxicity criteria. Results: Of the 24 registered patients, 22 received the DCs injections. Moreover, of the 14 patients that applied for the tolerance test, only 11 patients completed it because 3 patients withdrew their testing agreement. A grade 3 or more side effect, which was possibly related to the DC injection, did not occur in additional patients. The $12{\times}10^6$ DC injection was identified as the maximum tolerable dose, and was then injected in an additional 8 patients. Patients tolerated the injection fairly well, with no fatal side effects. In order to assess the feasibility of DC immunotherapy, the response was evaluated in other hepatic lesions outside of the targeted hepatic lesion. The response evaluation was performed in 15 of the 17 patients who received at least 4 injections. Stable and progressive disease was found in 4 and 11 patients, respectively. Conclusion: The DC-based immunotherapy and radiotherapy is theoretically synergistic for the local control and systemic control. The $DCVac/IR^{(R)}$ immunotherapy combined with irradiation was tolerable and safe in the evaluated cases of refractory colorectal cancer with multiple liver metastases. Future work should include well designed a phase II clinical trials.