• 산학경영연구
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• 제12권
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• pp.161-187
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• 1999

본 연구는 직무특성과 조직시민행동간의 관계가 구성원들의 재직기간과 성취욕구수준에 따라 어떻게 달라지는가(조절효과)를 검증하고자 하였다. 직무특성과 조직시민행동간의 관계에 대한 이론적 배경은 Hackman & Oldham(1980), Karambayya(1989) 및 Van Dyne 등(1994)의 연구를 바탕으로 하였다. 그리고 조절변인의 역할과 검증방법에 대하여는 Baron & Kenny(1986), Katz(1978) 등의 연구를 근거로 하였다. 이를 검증하기 위하여 원주지역 초 중등교사 698명이 최종 표본집단으로 이용되었다. 조절효과의 검증을 위한 분석기법은 Cohen & Cohen(1983)의 조절회귀분석을 이용하였다. 다중회귀분석결과 조직시민행동에 미치는 효과는 직무다양성이 가장 큰 것으로 나타났으며, 직무중요성과 자율성은 시민정신에만 영향을 미치고, 직무정체성은 조직시민행동의 모든 구성 요소에 대하여 영향을 미치지 않는 것으로 분석되었다. 조절회귀분석결과 성취욕구가 낮은 집단의 경우는 직무다양성과 직무정체성이 예의성과 이타주의에 미치는 효과가 현저하며, 성취 욕구가 높은 집단에서는 직무중요성과 자율성이 스포츠맨십에 미치는 효과가 현저히 높은 것으로 나타났다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.16.1-16.9
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• 2016

Background: The association of biomaterial combined with repair factor-like platelet-rich plasma (PRP) has prospective values. Bovine-derived xenograft has been identified as an osteoconductive and biocompatible grafting material that provides osseointegration ability. PRP has become a valuable adjunctive agent to promote healing in a lot of dental and oral surgery procedures. However, there are controversies with respect to the regenerative capacity of PRP and the real benefits of its use in bone grafts. The purpose of this study was to assess the influence of PRP combined with xenograft for the repair of peri-implant bone defects. Methods: Twelve rabbits were used in this study, and the experimental surgery with implant installation was performed simultaneously. Autologous PRP was prepared before the surgical procedure. An intrabony defect (7.0 mm in diameter and 3.0 mm deep) was created in the tibia of each rabbit; then, 24 titanium dental implants (3.0 mm in diameter and 8.5 mm long) were inserted into these osteotomy sites. Thus, a standardized gap (4.0 mm) was established between the surrounding bony walls and the implant surface. The gaps were treated with either xenograft alone (control group) or xenograft combined with PRP (experimental group). After healing for 1, 2, 3, 4, 5, and 6 weeks, the rabbits were sacrificed with an overdose of KCl solution. Two rabbits were killed at each time, and the samples including dental implants and surrounding bone were collected and processed for histological analysis. Results: More newly formed bone and a better bone healing process were observed in control group. The histomorphometric analysis revealed that the mean percentage of bone-to-implant contact in the control group was significantly higher than that of the experimental group (25.23 vs. 8.16 %; P < 0.05, independent-simple t test, analysis of variance [ANOVA]). Conclusions: The results indicate that in the addition of PRP to bovine-derived xenograft in the repair of bone defects around the implant, PRP may delay peri-implant bone healing.

• 한국지반공학회논문집
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• 제15권6호
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• pp.307-317
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• 1999

본 연구에서는 기존의 액상화 평가방법과 국내의 지진규모(M=6.5)를 고려한 수정 상세예측법을 비교 분석하였다. 액상화 발생 가능성은 흙의 액상화 저항강도와 지진에 의해 토층내에 유발되는 전단응력을 비교하여 평가하였다. 지진에 의한 전단응력은 지진응답해석을 이용하여 산정하며 흙의 액상화 저항강도는 진동삼축시험결과를 이용하여 산정한다. 진동삼축시험은 상대밀도(50%, 60%, 70%)와 초기유효구속압(70kPa, 100kPa, 150kPa) 그리고 세립분함유량(10%, 20%, 30%)을 변화시키며 시료를 재성형하여 수행하였다. 기존의 액상화 평가방법과 수정 상세 예측법 결과를 비교해 볼 때, 수정 상세 예측법은 연약한 사질토지반$(FS \leq1.5)$에서 액상화 안전율을 기존 평가방법에 비하여 크게 산정하는 것으로 나타났다. 본 연구결과를 토대로 액상화 발생가능성 판정시, 진동삼축시험에 기초한 수정 상세 예측법을 이용하도록 제안하였다. 또한 국내 발생 지진규모 6.5를 고려한 수정 상세 예측법에서의 액상화가 발생할 수 있는 최대심도는 약 15m인 것으로 나타났다.

• 대한치과보철학회지
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• 제40권5호
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• pp.484-492
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• 2002

The selection of the maxillary anterior artificial teeth is made primarily for esthetics and they must be in harmony with the surrounding oral environment. However the selection of artificial teeth is based on the large degree of subjective judgement or the dentists, therefore, this is one of the most unscientific processes. This study was performed to determine clinically whether there is correlation among the width of the maxillary central incisor(WMCI), the intercanine distance (ICD) the facial width(FW), and the interalar nasal width(IAW) in Korean adults, and to provide the selection standards for the maxillary anterior artificial teeth. The casts were obtained from 91 undergraduate dental students(49 males and 42 females) with Angle's class I occlusion presenting well-arranged intact anterior teeth. The WMCI and ICD were measured on the casts with a vernier calipers($Miltex^{(R)}$, Germany). The photographic procedures under standardized conditions were performed to record each subject's frontal face using digital camera($Olympus^{(R)}$, C-2500L, Japan). The FW and IAW were measured with image analyzer($Image-Pro^{(R)}$ PLUS. media cybermetrics. USA). The results were obtained as follows : 1. The mean WMCI was $8.11{\pm}0.67mm$, ICD was $37.88{\pm}2.15mm$, FW was $141.29{\pm}5.84mm$. and IAW was $37.85{\pm}2.29 mm$. 2. The ratios of FW/WMCI, FW/ICD, IAW/ICD were 17.4, 3.7, 1.0 respectively. 3. All measurements(WMCI, ICD, FW, and IAW) of male group were longer than those of female group significantly in Student's t-test(p<0.01). 4. There was significant correlation between WMCI, ICD, FW, and IAW in Pearson's correlation analysis(p<0.01). 5, The relationship between IAW and ICD shows the strongest correlation among six combinations in linear regression analysis($R^2$=0.753, Y=7.046+0.815X). The FW and IAW could be very reliable guides for the selection of the maxillary anterior artificial teeth.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.417-424
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• 2010

The purpose of this study was to detect significant SNPs for carcass quality traits using DNA chips of high SNP density in Hanwoo populations. Carcass data of two hundred and eighty nine steers sired by 30 Korean proven sires were collected from two regions; the Hanwoo Improvement Center of National Agricultural Cooperative Federation in Seosan, Chungnam province and the commercial farms in Gyeongbuk province. The steers in Seosan were born between spring and fall of 2006 and those in Gyeonbuk between falls of 2004 and 2005. The former steers were slaughtered at approximately 24 months, while the latter steers were fed six months longer before slaughter. Among the 55,074 SNPs in the Illumina bovine 50K chip, a total of 32,756 available SNPs were selected for whole genome association study. After adjusting for the effects of sire, region and slaughter age, phenotypes were regressed on each SNP using a simple linear regression model. For the significance threshold, 0.1% point-wise p value from F distribution was used for each SNP test. Among the significant SNPs for a trait, the best set of SNP markers were selected using a stepwise regression procedure, and inclusion and exclusion of each SNP out of the model was determined at the p<0.001 level. A total of 118 SNPs were detected; 15, 20, 22, 28, 20, and 13 SNPs for final weight before slaughter, carcass weight, backfat thickness, weight index, longissimus dorsi muscle area, and marbling score, respectively. Among the significant SNPs, the best set of 44 SNPs was determined by stepwise regression procedures with 7, 9, 6, 9, 7, and 6 SNPs for the respective traits. Each set of SNPs per trait explained 20-40% of phenotypic variance. The number of detected SNPs per trait was not great in whole genome association tests, suggesting additional phenotype and genotype data are required to get more power to detect the trait-related SNPs with high accuracy for estimation of the SNP effect. These SNP markers could be applied to commercial Hanwoo populations via marker-assisted selection to verify the SNP effects and to improve genetic potentials in successive generations of the Hanwoo populations.

• 한국병원경영학회지
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• 제14권4호
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• pp.149-162
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• 2009

The purpose of this study is to design strategic hospital service based on each hospital's features. For this study, an assessment was conducted by 398 in-patents of one university hospital located in Seoul. The self-questionnaires, which were investigated from Oct. 15th to 29th in 2008, compared central reception desk with ward reception desk in satisfaction and re-use rate of patients. The major results of this study are as follow. First, according to each reception desk user, they have different satisfaction of it. As for the staff kindness, admission procedure, discharge procedure and manner of staff, those made patients be gratified as well. Second, when it comes to the intention of re-use, there were no significant features between them. Only convenience in admission and discharge procedure, however, was an attractive factor for the recommendation. Third, this study found out the reasons for higher re-use rate of central reception desk users. Regarding service, they were contented with the time for test and treatment. As for the hospital service, they would like to re-use this hospital because of convenient steps of paying interim fee and getting certificates. Forth, this study found out the reasons for higher re-use rate of ward reception desk users. As a point of hospital service view, they responded that respected privacy, hospital facility and general service were good for staying. As for the manner of staff, they mentioned nurses and staff in charge and whole staff members were kind. When it comes to the procedures of patient management, steps of discharge and paying interim fee were convenience. In conclusion, the results of this study suggest that providing a ward reception desk service can boost the satisfaction and re-use rate of in-patients. Furthermore, this strategic management method would be good for not only cutting the moving line but also efficient in-patient care system. These results can be used for the strategic hospital marketing field, as well. Even though this study has a limitation of the targeted populations which were only in a ward reception desk running hospital, it can say that having competitiveness in satisfaction of hospital service is good for promoting and differencing each hospital. Consequently, whole general management system would be adjusted first for differencing each hospital; however, this sort of additional factor should be concerned as well. I expect that this study would give meaningful data for designing strategic and differencing marketing method to lots of hospitals.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.40-44
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• 2003

Soil-borne infectious disease including Pythium aphanidermatum and Rhizoctonia solani causes severe damage to plants, such as cucumber. This soil-borne infectious disease was not controlled effectively by chemical pesticide. Since these diseases spread through the soil, chemical agents are usually ineffective. Instead, biological control, including antagonistic microbe can be used as a preferred control method. An efficient method was developed to select an antagonistic strain to be used as a biological control agent strain. In this new method, surface tension reduction potential of an isolate was included in the ‘decision factor’ in addition to the other factors, such as growth rate, and pathogen inhibition rate. Considering these 3 decision factors by a statistical method, an isolate from soil was selected and was identified as Bacillus sp. GB16. In the pot test, this strain showed the best performance among the isolated strains. The lowest disease incidence rate and fastest seed growth was observed when Bacillus sp. GB16 was used. Therefore this strain was considered as plant growth promoting rhizobacteria (PGPR). The action of surface tension reducing component was deduced as the enhancement of wetting, spreading, and residing of antagonistic strain in the rhizosphere. This result showed that new selection method was significantly effective in selecting the best antagonistic strain for biological control of soil-borne infectious plant pathogen. The antifungal substances against P. aphanidermatum and R. solani were partially purified from the culture filtrates of Bacillus sp. GB16. In this study, lipopeptide possessing antifungal activity was isolated from Bacillus sp. GB16 cultures by various purification procedures and was identified as a surfactin-like lipopeptide based on the Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), high performance liquid chromatography mass spectroscopy (HPLC-MS), and quadrupole time-of-flight (Q-TOF) ESI-MS/MS data. The lipopeptide, named GB16-BS, completely inhibited the growth of Pythium aphanidermatum, Rhizoctonia solani, Penicillium sp., and Botrytis cineria at concentrations of 10 and 50 mg/L, respectively. A novel method to prevent the foaming and to provide oxygen was developed. During the production of surface active agent, such as lipopeptide (surfactin), large amount of foam was produced by aeration. This resulted in the carryover of cells to the outside of the fermentor, which leads to the significant loss of cells. Instead of using cell-toxic antifoaming agents, low amount of hydrogen peroxide was added. Catalase produced by cells converted hydrogen peroxide into oxygen and water. Also addition of corn oil as an oxygen vector as well as antifoaming agent was attempted. In addition, Ca-stearate, a metal soap, was added to enhance the antifoam activity of com oil. These methods could prevent the foaming significantly and maintained high dissolved oxygen in spite of lower aeration and agitation. Using these methods, high cell density, could be achieved with increased lipopeptide productivity. In conclusion to produce an effective biological control agent for soil-borne infectious disease, following strategies were attempted i) effective screening of antagonist by including surface tension as an important decision factor ii) identification of antifungal compound produced from the isolated strain iii) novel oxygenation by $H_2O_2-catalase$ with vegetable oil for antifungal lipopeptide production.

• 한국환경농학회지
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• 제14권1호
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• pp.82-87
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• 1995

육상생태계에서 농약 및 일반화학물질의 환경생태독성을 평가할 때, 중요 항목으로 지렁이(earthworm)에 대한 독성시험 자료가 필요하다. 그런데 국내에서 지렁이 독성시험을 할 때, 가장 문제가 되는 점은, 독성시험을 목적으로 사육하는 지렁이가 없어, 결과의 신뢰성에 다소 문제가 있다. 따라서 본 연구에서는, 독성시험에 사용하는 종인 Lumbricus rubellus, Eisenia foetida를 실험실에서 사육할 수 있도록, 사육배지의 조성을 달리하여 성장인자의 차이를 조사하였다. 사육배지는 OECD Guideline에서 제시한 인공토양을 기본으로 하여(인공토양 Ⅰ), 조성을 달리한 인공토양 Ⅱ와 Ⅲ을 사용하였고, 먹이는 같게 공급하였다. 결과는 다음과 같다. 1) 지렁이 생체량은 L. rubellus의 경우, 인공토양Ⅰ에서 가장 양호하였고, E. foetida는 인공토양 Ⅰ과 Ⅱ에서 양호하였으므로, 이 두종을 함께 사육하는 경우는 인공토양 Ⅰ의 조성을 가진 배지에서 사육하는 것이 생체량의 증가면에서는 유리할 것이다. 2) 누적난포(cocoon) 생산량은 두종 모두 인공토양 Ⅰ에서 가장 많았고, L. rubellus는 E. foetida에 비하여 약 3배 많이 생산하였으므로, 본 실험에서의 사육조건은 L. rubellus에게 더 적합한 것으로 판단된다. 3) 누적치사율은 모든 처리 토양에서 두종 모두 10% 이하로 낮았다. 4) 난포당 부화된 지렁이 수는 $1.5 {\sim} 2.3$ 마리로 종간 및 토양처리에 따른 차이에 크지 않았다. 따라서 위의 두종을 실험실에서 사육하는데는 L. rubellus의 경우 인공토양 Ⅰ의 배지로 해서, 현재의 먹이를 공급해 주면, 비교적 잘 사육할 수 있으나, E. foetida의 경우는 사육배지뿐만 아니라, 먹이에 대한 문제도 검토되어야 할 것이다.

• 보건행정학회지
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• 제23권2호
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• pp.152-161
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• 2013

Korea has a single National Health Insurance program and all citizens are covered under this program, accounting 97% of the population, approximately 50 million people. Claims submitted by Health care providers are reviewed by Health Insurance Review and Assessment (HIRA) for the reimbursement. HIRA database contains not only individual beneficiary's information, but also healthcare service information such as diagnosis, procedures, prescriptions and tests for them. HRA database has gained attention as importance source for research due to its rich healthcare information and the demand of HIRA database has increased. Due to its tremendous size, however, researchers have had problems in accessing the database to conduct research. To meet this demand, we conducted a study to develop the inpatient sample data from HIRA database for research. This study has two purposes: 1) to determine a needed sample size; 2) to test reliability and validity of the sample data. We determined an adequate sample size to ensure representativeness and generality with additional consideration for convenience of calculation. The minimum sample size was 729,904 for the generality, and 488,861 for representativeness. After considering the convenience of calculation, our final sample size was 13% of the population, which was about 7.7 million beneficiaries. Age (5 years interval) and gender were used as stratification variables for sampling. In order to examine whether this sample data appropriately reflect population, we tested the reliability and validity of the sample data. From the sample data, we computed average expenditure of total claims per inpatient for 2011, frequency of top 30 disease, estimation of the number of stroke patients from the sample data, and then compared them to those from the population. Results confirmed reliability and validity of the sample data.

• 대한교통학회지
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• 제23권4호
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• pp.7-16
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• 2005

항공기 운항에서 이륙과 착륙단계는 가장 어려우며 많은 사고가 발생되는 위험한 과정이다. 이륙단계에서 발생될 수 있는 비상상황 가운데 가장 심각한 것은 이륙단념이다. 이륙단념 관련 사고의 대부분은 활주로 이탈사고로 연결되었는데 이와 관련하여 미국 NTSB는 사고발생의 주원인을 이륙이나 정지를 결심하는 시간지연으로 분석하였다. 본 연구는 이와 같은 이륙단념속도(시간)에 대한 조종사들의 인지도와 적합성을 검토하였는데, 먼저 현장에서 항공기를 운용하는 조종사를 대상으로 한 이륙단념 설문을 통하여 이와 관련된 인지여부를 비롯한 기초자료를 측정하였고, 그 후 무작위로 선정된 조종사를 대상으로 모의비행장치(Simulator)를 이용하여 이륙단념 상황을 부여하고 이에 따른 반응시간을 측정하여 현재 적용하는 기준과 비교하였다. 설문 결과, 일부 조종사들은 비행규정에 적용된 이륙단념의 기준과 현행 절차를 불만족스럽게 생각하고 있었다. 모의비행장치의 측정결과, 현장조종사의 이륙단념시간이 항공기 비행규정보다 1.5 초 더 소요되는 것으로 나타났으며 결국 현행 규정에 의한 Y1 속도에서 이륙단념을 하는 경우, 활주로 이탈로 이어질 가능성이 높은 것으로 분석되었다. 따라서 이륙단념 사고를 줄이기 위해서는 관련 규정에 대한 지속적인 교육이 필요하며, 실제로 안전한 이륙단념을 위하여 $V_1$ 속도를 6노트 줄여서 사용하여야 이륙단념에 대한 안전성이 확보될 것이다.