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An Analysis of Globalization Trends in the Korean Scientific Knowledge: Investigating the Factors of the Scientific Collaboration Structure in the Science Citation Indexed Journals published in Korea (한국 과학지식의 세계화 추이 분석: 한국 SCI 저널의 발전 양상과 분야별 차이)

  • Kim, Young Jin
    • Journal of Science and Technology Studies
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    • v.12 no.2
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    • pp.1-31
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    • 2012
  • Rapid globalization process is applying to Science field in Korea. Until now, most researches and government's announcement used to examine the scientific level of Korea by using the number of publications in the SCI Journals. I investigate other aspects of the scientific globalization: a scientific collaboration trend, participations of foreign researchers, and the national level of collaboration networks. There are increasing patterns in collaboration and foreign researchers' participation, and the Impact Factors of the Journals were preceded by inflating trend in the participations of foreign researchers. Also, the breadth and the density are different from each science fields in the national level of collaboration networks. These findings are related to the process of globalization in the Korean science journals and the science fields.

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Effects of Spouse-Participated Health Coaching for Male Office Workers with Cardiocerebrovascular Risk Factors (심뇌혈관질환 위험요인을 가진 남성 사무직근로자를 위한 배우자참여 건강 코칭의 효과)

  • Kang, So Hee;Hwang, Seon Young
    • Journal of Korean Academy of Nursing
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    • v.49 no.6
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    • pp.748-759
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    • 2019
  • Purpose: This study aimed to examine the effect of spouses participating in health coaching on stage of the change, health behaviors, and physiological indicators among male office workers with cardiocerebrovascular disease (CVD) risk factors and compare the findings with trainers who provided health coaching only to workers. Methods: A quasi-experimental pretest-posttest design was used. Convenience sampling was used to recruit participants from a manufacturing research and development company in the city of Gyeonggi province. The health coaching program for the experimental group (n=26) included individual counseling sessions according to workers' stage of change, and provision of customized health information materials on CVD prevention to workers and their spouses for 12 weeks through mobile phone and email. Results: After 12 weeks of intervention, the total score for health behavior, and scores on the sub-areas of exercise and health checkups significantly improved in the experimental group, but there were no significant differences in the scores of stage of the change and physical indicators. The results of a paired t-test showed a significant decrease in the body mass index, abdominal circumference, systolic blood pressure, diastolic blood pressure, total cholesterol and triglyceride values, and a significant increase in the high-density lipoprotein cholesterol value in the experimental group after the intervention. Conclusion: To improve the health of male workers with CVD risk factors in the workplace, sharing health information with their spouses has proven to be more effective than health coaching for only workers. Therefore, it is important to develop strategies to encourage spousal participation when planning workplace health education for changing health-related behaviors.

Effects of $GeO_2$ Addition on the Stabilities of $PbO-Bi_2O_3-Ga_2O_3$ Glasses ($GeO_2$의 첨가가 $PbO-Bi_2O_3-Ga_2O_3$ 유리의 안정화에 미치는 영향)

  • Choi, Yong-Gyu;Heo, Jong;Ryou, Sun-Youn
    • Journal of the Korean Ceramic Society
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    • v.32 no.11
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    • pp.1269-1275
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    • 1995
  • Effects of GeO2 addition on the thermal and structural stabilities of PbO-Bi2O3-Ga2O3 glasses were studied. Thermal stabilities, as assessed by the weighted thermal stability factors [(Tx-Tg)/Tg], increased with GeO2 concentraton from 0.097 to 0.210 with the addition of 20 mol% GeO2. Increasing GeO2 content resulted in the decrease of apparent density, molar volume, refractive index and thermal expansion. On the other hand, IR transmission cut-off (λT=50%) moved from 6.73${\mu}{\textrm}{m}$ for the ternary PbO-Bi2O3-Ga2O3 glass to shorter wavelength side, 5.98${\mu}{\textrm}{m}$ for a glass containing 20mol% GeO2. There were little change with GeO2 content, however, in the activation energies for the viscous flow of approximately 140 kcal/mole within the temperature interval of 300~50$0^{\circ}C$. Addition of GeO2 to PbO-Bi2O3-Ga2O3 glasses enhanced the thermal and structural stabilities significantly at the expense of their infrared transmittance. An appropriate compsomise between these two opposite trends should be made following the specifications of the final applications.

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Crystallization of Hydrazinium Nitroformate(HNF) as Eco-friendly Oxidizer (친환경 산화제 HNF 결정화 연구)

  • Kim, Jina;Kim, Min Jun;Min, Byoung Sun
    • Journal of the Korean Society of Propulsion Engineers
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    • v.20 no.6
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    • pp.76-82
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    • 2016
  • Recently, environmental sustainability of the transitional explosives and propellants is an issue of growing importance in energetic materials. For examples, ammonium perchlorate(AP) as an solid propellants oxidizer could create a poisonous gas and atmospheric pollutions, such as HCl. Among the several oxidizers, hydrazinium nitroformate(HNF) is an effective candidate substance for eco-friendly oxidizer, which has high density, pressure index, and less smog generating property during combustion for the thrust control system. This study was controlled the size distribution and shapes through various conditions. Length and diameter ratio(L/D) of crystals has below 1 : 3, and the particle size was two types of $200{\mu}m$ and $50{\mu}m$.

Evaluation of Waist Circumference Cut-off Values as a Marker for Fatty Liver among Japanese Workers

  • Abe, Naomi;Honda, Sumihisa;Jahng, Doosub
    • Safety and Health at Work
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    • v.3 no.4
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    • pp.287-293
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    • 2012
  • Objectives: Metabolic syndrome has received attention as a risk factor for cardiovascular disease, with particular importance attached to visceral fat accumulation, which is associated with lifestyle-related diseases and is strongly correlated with waist circumference. In this study, our aim is to propose waist circumference cut-off values that can be used as a marker for fatty liver based on a sample of workers receiving health checkups in Japan. Methods: This study was conducted in a total of 21,866 workers who underwent periodic health checkups between January 2007 and December 2007. The mean age of the subjects was 47.4 years for men (standard deviation [SD]: 8.0) and 44.7 years for women (SD: 6.9). Evaluation included abdominal ultrasound and measurement of waist circumference, body mass index, fasting blood glucose, triglycerides, high-density lipoprotein cholesterol, and blood pressure. Results: Based on receiver operating characteristic curve analysis, the optimal waist circumference cut-off values were shown as 85.0 cm (sensitivity 0.72, specificity 0.69) for men and 80.0 cm (sensitivity 0.75, specificity 0.78) for women. Conclusion: Abdominal ultrasound is the most efficient means of diagnosing fatty liver, but this examination seldom occurs because the test is not routinely performed at workers' health checkups. In people found to have a high risk of fatty liver, recommendations can be made for abdominal ultrasound based on the waist circumference cut-off values obtained in this study. That is, waist circumference can be used in high risk individuals as an effective marker for early detection of fatty liver.

The Study on the Characteristic of Mono Crystalline Silicon Solar Cell with Change of $O_2$ Injection during Drive-in Process and PSG Removal (단결정 실리콘 태양전지 도핑 확산 공정에서 주입되는 $O_2$ 가스와 PSG 유무에 따른 특성 변화)

  • Choi, Sung-Jin;Song, Hee-Eun;Yu, Gwon-Jong;Lee, Hi-Deok
    • 한국태양에너지학회:학술대회논문집
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    • 2011.04a
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    • pp.105-110
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    • 2011
  • The doping procedure in crystalline silicon solar cell fabrication usually contains oxygen injection during drive-in process and removal of phosphorous silicate glass(PSG). In this paper, we studied the effect of oxygen injection and PSG on conversion efficiency of solar cell. The mono crystalline silicon wafers with $156{\times}156mm^2$, $200{\mu}m$, $0.5-3.0{\Omega}{\cdot}cm$ and p-type were used. After etching $7{\mu}m$ of the surface to form the pyramidal structure, the P(phosphorous) was injected into silicon wafer using diffusion furnace to make the emitter layer. After then, the silicon nitride was deposited by the PECVD with 80 nm thickness and 2.1 refractive index. The silver and aluminium electrodes for front and back sheet, respectively, were formed by screen-printing method, followed by firing in 400-425-450-550-$880^{\circ}C$ five-zone temperature conditions to make the ohmic contact. Solar cells with four different types were fabricated with/without oxygen injection and PSG removal. Solar cell that injected oxygen during the drive-in process and removed PSG after doping process showed the 17.9 % conversion efficiency which is best in this study. This solar cells showed $35.5mA/cm^2$ of the current density, 632 mV of the open circuit voltage and 79.5 % of the fill factor.

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The technical transfer on manufacture technique of environmental-friendly leather for improved effluent in beamhouse process (피혁 폐수의 오염 저감을 위한 피혁 준비 공정 기술 보급 (Hair saving liming agent 제조 기술 및 공정 적용 기술 보급))

  • Yun, Jous-Kuk;Cho, Do-Kwang;Park, Jae-Hyung;Baek, In-Kyu;Kim, Han-do
    • Clean Technology
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    • v.10 no.2
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    • pp.111-120
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    • 2004
  • Manufacturing with a chemical for eco-friendly leather for nitrogen decrease of leather falling hair process waste water and the falling hair process that a number to decrease with sulfuration water decrease, a pollution load of COD, BOD. In this study manufactured lining agent and the unhairing assist product which did urea, mercaptan by basic matter. As a result of having dealt in hair saving process, compared, and was recalled by the existing hair burning process recovered hair, increased approximately 2times. Grain state to influence the yield that was quality of leather and an index of productivity evaluation, an improvement of contraction phenomenon (drawing) were possible. Is increased going seal, tear strength property of matter and softness and touch leather native nature in wet blue. Also, it is possible confirmation with decrease being more possible than about 50% COD, T-N density in a hair saving waste water.

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Optimization of Drive-in Temperature at Doping Process for Mono Crystalline Silicon Solar Cell (단결정 실리콘 태양전지의 도핑 최적화를 위한 확산 온도에 대한 연구)

  • Cho, Sung-Jin;Song, Hee-Eun;Yoo, Kwon-Jong;Yoo, Jin-Soo;Han, Kyu-Min;Kwon, Jun-Young;Lee, Hi-Deok
    • Journal of the Korean Solar Energy Society
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    • v.31 no.1
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    • pp.37-43
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    • 2011
  • In this paper, the optimized doping condition of crystalline silicon solar cells with $156{\times}156\;mm^2$ area was studied. To optimize the drive-in temperature in the doping process, the other conditions except variable drive-in temperature were fixed. These conditions were obtained in previous studies. After etching$7\;{\mu}m$ of the surface to form the pyramidal structure, the silicon nitride deposited by the PECVD had 75~80nm thickness and 2 to 2.1 for a refractive index. The silver and aluminium electrodes for front and back sheet, respectively, were formed by screen-printing method, followed by firing in 400-425-450-550-$850^{\circ}C$ five-zone temperature conditions to make the ohmic contact. Drive-in temperature was changed in range of $830^{\circ}C$ to $890^{\circ}C$to obtain the sheet resistance $30{\sim}70\;{\Omega}/{\box}$ with $10\;\Omega}/{\box}$ intervals. Solar cell made in $890^{\circ}C$ as the drive-in temperature revealed 17.1% conversion efficiency which is best in this study. This solar cells showed $34.4\;mA/cm^2$ of the current density, 627 mV of the open circuit voltage and 79.3% of the fill factor.

A Case of Mesenteric Myxosarcoma in a Dog (개에서 발생한 장간막 점액육종의 한 증례)

  • Kim, Sang-Chan;Kim, Hyun-Wook;Choi, Ji-Hye;Jang, Jae-Young;Choi, Ul-Soo
    • Journal of Veterinary Clinics
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    • v.29 no.2
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    • pp.173-176
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    • 2012
  • A 6-year-old male Shih tzu dog was presented for evaluation of abdominal distention. Abdominal radiography and ultrasonography revealed a soft tissue density mass containing large amount of fluid. Ultrasonography-guided fine needle aspiration of the mass was performed and cytologic impression was granulation tissue with hematoma and fibroplasias. On exploratory laparotomy a mass was identified at the root of mesentery adhered to distal jejunum. Because the mass could not be separated from the attached jejuna loops, the mass and the adhered sites were surgically removed all together and enteroanastamosis was performed. Histologically a low grade myxosarcoma was diagnosed. Tumor cells were positive with alcian blue stain and Ki67 index by immunohistochemistry was 2.5. The dog recovered from surgery uneventfully, and has been in good condition without any signs of recurrence or metastasis for about 30 months after surgery.

A Study on the Flame Retardant Performance of MDF Wood According to Flame Retardant Treatment Method (방염처리 방법에 따른 MDF 목재의 방염성능에 관한 연구)

  • Cha, Jung-Min;Hyun, Seong-Ho;Kim, In-Beom;Yoon, Myung-O
    • Fire Science and Engineering
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    • v.25 no.6
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    • pp.146-155
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    • 2011
  • In the study, test was carried out to compare the flame retardant performance for the specimen of MDF wood to which field flame retardant treatment (post processing flame retardant) is applied, which is coated with flame retardant film of 5 companies, locally distributed, and MDF wood (nontreated, flame retardant film non-coated) to which aqueous or oil-based fire-retardant paint is applied. As a result of combustion test of MDF wood which was coated with flame retardant film of 5 companies, 2 products showed suitable values in 4 criteria, but other 3 products showed 10~40 % disqualification rate. In regard of characteristics of fire-retardant paint, oil-based fire-retardant paint is better than aqueous fire-retardant paint in flame retardant performance criteria, but MDF wood to which oilbase fire-retardant paint was applied was shown to have higher toxicity index grade than MDF wood to which aqueous fire-retardant paint was applied relatively.