• 한국항공우주학회지
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• 제31권6호
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• pp.23-29
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• 2003

얇은 익형 주위에 다양한 응축 과정을 수반하는 상대 습도가 100%인 포화 습공기 천음속 이상 유동에 대하여 연구하였다. 본 연구는 Rusak 과 Lee[11, 12]가 발전시킨 그리고 응축에 의한 열 증가의 효과를 포함하는 확장된 천음속 미 교란 모델을 사용하였고, 응축 과정은 서로 다른 두 가지 형태의 응축 과정을 고려한다. 먼저, 비 평형 균질 과정(nonequilibrium and homogeneous process)에서의 응축 질량비는 고전적 핵형성 이론과 작은 물방울 성장이론에 따라 계산되고, 평형과정(equilibrium process)에서의 응축 질량비는 등엔트로피 가정으로부터 계산된다. 유동 방정식과 응축 방정식들은 반복수치 계산법을 사용하여 그 해를 구하였다. 상류 유동 조건을 같게 하여 얻은 수치계산 결과들은 유동구조, 응축장, 그리고 익형 표면에서의 압력분포 등을 묘사한다. 유동특성, 즉 충격파의 위치와 강도 그리고 익형의 압력분포 등은 서로 다른 두 응축과정에서 각각 다른 유동특성을 나타냈다. 하지만, 각각의 응축과정에서 응축 결과로 생긴 열 증가는 유동거동에 상당한 변화를 야기 시키고 익형의 공력 성능에도 상당한 영향을 미친다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.43-48
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• 2004

교통체계의 발달은 지리공간 위에서 시간거리와 비용거리를 단축시켜 시공간과 비용공간의 상대적 수렴을 가져온다. 고속도로와 고속철 둥 사회간접자본시설은 지역발전에 절대적인 파급효과를 미친다. 목포는 서해안고속도로와 호남고속철도의 영향권 내 지역으로서, 여름휴가철(성수기) 외지의 관광객은 목포와 같은 항구도시를 찾지만, 연안여객선의 수용능력이 관광객(도착차량)의 수를 포용하지 못하므로 balking현상이 발생한다. 이 연구에서는 ARENA의 개념과 속성을 이해하고 목포항 연안여객선 운영현황 시뮬레이션을 통하여 balking의 진상을 면밀히 분석, 연안도로의 정체현상 해결을 위한 효율적인 여객선 운영방안을 모색하고자 한다. 이 논문은 고속도로와 고속철의 영향권 테에 있는 항구도시의 경제부흥에 일조 할 수 있다는 정성적 효과를 제시하는데 의의가 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1638-1652
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• 2000

Prolific females require better nutrition and feeding practice because of larger litter size and the substantial decline in body fat. Life-time pig output will be compromised if body protein and fat are not properly managed. First litter females are especially vulnerable because they can loose ${\geq}15%$ of whole-body protein. Conservation of body protein mass during first lactation minimizes wean to estrus interval and increases second litter size (up to 1.2 pigs). The ability to influence litter-size by amino acid nutrition is a new dimension in our understanding. A P2 fat depth below 12 mm at farrow and below 10 mm at wean compromised wean to estrus interval (>2 d) and next litter size (0.5 to 1.5 pigs) in sows. It is now clear that a 'modest' excess of feed during the first 72 h of pregnancy decreases embryo viability so that the potential for an increased litter size at birth is not realized. The capacity for milk production by prolific young sows is 25% higher than the standard used previously (NRC, 1988). First litter females averaged 9.82 kg milk/d for a 21 d lactation. Second and third litter counterparts averaged 10.35 kg/d. Milk production was 95% of peak by 10 d of lactation and sows were in greatest negative energy and lysine balance during the first 6 d. Nearly 45% of the total loss in body protein occurred within the first 6 d, but this could reduced to 30-35% by using a more aggressive feeding strategy after parturition. There appear to be 2 phases in lactation for lysine need (d 2-12 vs 12-21). Feeding to the higher level alleviates the second litter size decline. The lysine requirement for lactation can be predicted with accuracy, but we are not able to predict the second limiting amino acid. Mammary uptake of valine relative to lysine and recent work with practical diets suggest that the recent NRC (1998) pattern is realistic and that threonine and valine could be co-limiting for corn-soy diets for prolific sows nursing 10-11 pigs. Empirical studies are needed to refine the ideal pattern so that synthetic lysine can be used with more confidence. Milk fat output for the elite sow is extraordinary and poses an unnecessarily high energetic cost. Methods that reduce mammary fat synthesis will benefit the sow and may enhance piglet growth.

• 기술혁신학회지
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• 제10권3호
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• pp.555-579
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• 2007

본 연구는 제3세대 혁신정책의 주요 특성으로 나타나는 총체적 혁신정책을 살펴보고 실제 구현되는 모습을 핀란드와 우리나라의 사례를 통해 살펴보았다. 양 국가 모두 혁신정책의 영역이 경제발전이라는 단선적인 목표에서 벗어나 지속 가능한 발전, 균형발전, 삶의 질 제고 등 사회 전반의 변화와 관련된 것으로 외연을 확장하고 있다. 또한 기술혁신을 국정 운영의 중심에 두고, 인력, 교육, 지역 등 관련 정책을 새롭게 재배열하는 모습도 함께 이루어지고 있다. 특히 우리나라는 참여정부 출범이후 과학기술중심사회 구축이 국정 과제로 등장하면서 제3세대 혁신 정책의 맹아적 모습이 나타나고 있다. 반면 실제 구현 정도와 모습은 양 국가 간 차이가 있다. 핀란드는 북유럽 국가의 제도적 특성인 전형적인 코포라티즘의 전통으로 인해 전환의 장을 마련하고 추진하는 "공론의 장"을 활성화시켜 왔다. 정부의 지원 체계 또한 특정 부처의 개별 업무가 아니라 임무를 중심으로 공동의 프로그램과 수단을 개발 집행함으로써 정책의 실효성을 높여 왔다. 우리나라는 혁신 정책의 개념은 앞서 있으나, 실제 정책을 추진하거나 일하는 방식은 아직도 발전국가 시대의 틀을 유지하고 있다. 또한 전환 전반이 하향식으로 이루어지면서, 민간부문과 시민사회의 능동적인 참여가 부족했으며, 이로 인해 전환을 시도하려는 다양한 노력이 아직 탄력을 받지 못하고 있다.

• 유통과학연구
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• 제11권2호
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• pp.57-70
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• 2013

Purpose - The objective of this paper is to explain the successful methods for the revitalization of distribution and logistics of the least developed FEZs (Saemangum, Yellow-sea, and Deagu-Kyengbuk) in Korea. With the recent changes in the economic terrain of Northeast Asia as with the rise of China, Korea has developed a logistics hub concept for improving the efficiency of logistics and distribution industry and its distribution and logistics policy has received positive worldwide evaluation. Therefore, we face severe competition and must always look for ways to address these problems. Research design, Data, Methodology - This study adopts two methods to propose successful revitalization of distribution and logistics in the least developed FEZ. The first method investigates the limitation of these FEZs by analyzing the statutes, and the second one follows comparable cases. Thus, we first reviewed the efficient strategic political alternatives for the least developed FEZ, Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk, through the relative institution system, law, and future plans. Next, we studied the Bin-hai Economic Free Section (Zone) in China as a comparable example. In order to analyze the competitiveness of logistics in the three FEZs (Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk), the total factor productivity growth of regional manufacturing industries is divided into three sources: the external trade effect, scale effect, and technical change effect. However, this paper does not test for a positive contribution of external trade, which is a reason of non-building on these FEZs. A FEZ that shows a larger external trade effect than the others will have a comparative advantage in the logistics infrastructure and policy support. This study presented the newly applied Bin-hai FEZ in China, in order to make the studied FEZ as successful by applying the strategy of its distribution and logistics center. Results - In Korea, there is an increased focus on the benefit of the regional development of regions such as the Free Economic Zones (FEZ). We have six FEZs, Inchon, Busan-Jinhae, Guangyang, Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk. However, our FEZs do not have various supporting factors needed for the logistics and distribution industry. Korea designated the above six places as FEZ and has operated to enhance national competitiveness and ensure a balanced regional development since 2003. However, most FEZs did not receive favorable feedback in the first business performance evaluation and it is necessary to take action for substantial improvements. Conclusions - Especially, over the past 10 years, even though the FEZ policy has been implemented in an effort to promote success in distribution and logistics, there are still many underdeveloped industries in logistics. The main problem is the absence of revitalization of the high value added performance in the distribution and logistics industry. However, there is a limitation to this study. We have used non-empirical method based on a case study to arrive at our findings. Future studies should use appropriate statistical methods to supplement our results and provide a solution to this problem.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권11호
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• pp.505-513
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• 2006

The present study investigated the influence of the content of $Al_2O_3+Y_2O_3$ sintering additives on the microstructure, mechanical and electrical properties of the pressureless-sintered $SiC-ZrB_2$ electroconductive ceramic composites. Phase analysis of composites by XRD revealed mostly of ${\alpha}-SiC(4H),\;ZrB_2,\;{\beta}-SiC(15R)$ and In Situ $YAG(Al_5Y_3O_{12})$. The relative density and the flexural strength showed the highest value of 86.8[%] and 203[Mpa] for $SiC-ZrB_2$ composite with an addition of 8[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid at room temperature respectively. Owing to crack deflection and crack bridging of fracture toughness mechanism, the fracture toughness showed 3.7 and $3.6[MPa{\cdot}m^{1/2}]\;for\;SiC-ZrB_2$ composites with an addition of 8 and 12[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid at room temperature respectively. Abnormal grain growth takes place during phase transformation from ${\beta}-SiC\;into\;{\alpha}-SiC$ was correlated with In Situ YAG phase by reaction between $Al_2O_3\;and\;Y_2O_3$ additives during sintering. The electrical resistivity showed the lowest value of $6.5{\times}10^{-3}[({\Omega}{\cdot}cm]$ for the $SiC-ZrB_2$ composite with an addition of 8[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid at room temperature. The electrical resistivity of the $SiC-ZrB_2$ composites was all positive temperature coefficient(PTCR) in the temperature ranges from $25[^{\circ}C]\;to\;700[^{\circ}C]$. The resistance temperature coefficient showed the highest value of $3.53{\times}10^{-3}/[^{\circ}C]\;for\;SiC-ZrB_2$ composite with an addition of 8[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid in the temperature ranges from $25[^{\circ}C]\;to\;700[^{\circ}C]$. In this paper, it is convinced that ${\beta}-SiC$ based electroconductive ceramic composites for heaters or ignitors can be manufactured by pressureless sintering.

• 융합정보논문지
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• 제8권1호
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• pp.253-263
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• 2018

경기북부 지역 내 섬유패션산업은 23개 제조업종 중 가장 큰 비중(17.7%, 10인 이상 사업체 수 기준)을 차지하는 중추 기반산업이다. 하지만 소규모 공정별 임가공 업체가 대다수이고 최근 이 임가공업체에 오더를 주던 중대형 벤더의 해외이탈이 가속화됨에 따라 오더가 급감하고 있고 이로 인해 투자 감소로 이어지는 악순환 고리가 고착화되어 가고 있다. 이에 본 연구는 이러한 악순환 고리를 끊고 경기북부 섬유패션산업의 구조 고도화를 위한 정책요인을 분석하고 구체적 정책 제언을 위해. 각종 산업통계 데이터를 조사, 분석하여 관련 산업규모의 변화추이, 경영환경 변화 등을 파악한 결과와 관련 문헌조사 등의 선행연구결과 및 산 학 연 관 전문가의 의견조사를 바탕으로 AHP 연구모형(4개 계층, 36개 요소)을 설계하였고. 계층 간 및 계층 내 요인(요소)들 간 쌍대비교를 통해 상대적 중요도 및 우선순위를 도출하였다. 또한 이 연구모형 및 그 도출 결과를 반영한 섬유패션산업의 비전, 전략, 핵심과제 및 세부추진과제를 구체적으로 제안하여 본 연구결과의 유용성 및 활용성을 제고하였다.

• 한국토양비료학회지
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• 제29권4호
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• pp.411-418
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• 1996

대기오염물질에 대한 지표식물로서의 활용 가능성이 알려지고 있는 들깨 수원 16호를 대상으로 대기오염물질에 대한 식물의 반응에 중요하게 작용하는 기공의 개폐와 관련된 K와 EC를 주 변화요인으로하여 $NO_2$, $O_3$, $SO_2$ and $NO_2+SO_2$ 가스를 접촉시키면서 들깨의 가시적 지표성과 생장에 미치는 영향을 양액재배 실험으로 파악하고자 하였다. 들깨의 건물생산량은 55일 후에 K100 및 200mg/l 처리구에서 32.2 g/주로 가장 높았고, EC는 2.0 ds/m에서 16.3g/l으로 가장 높았다. 기공확산저항은 7-8위엽이 전개된 시기에 K 200mg/l와 2.0mg/l에서 가장 낮았다. 한편 K 50, 100mg/l, EC 0.5 ds/m 처리에서 대기오염가스의 접촉량의 증가에 따른 가시피해도의 증가가 가장 균일하게 나타났다. 따라서 K 50-100mg/l 수준, EC 0.5-1.0 dS/m 수준, 7-8위엽이 전개된 시에 들깨 수원 16호는 가장 뛰어난 대기오염 지표성을 나타내었다.

• 한국약용작물학회지
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• 제28권5호
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• pp.339-346
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• 2020

Background: Cnidium officinale Makino have been used in traditional medicine in Northeast Asia. Although gamma-ray mutagenesis has been used to develop breeding resources with novel characteristics, research on the radiation sensitivity of C. officinale Makino is limited. Hence, the optimal gamma-ray dosage for mutation breeding in C. officinale Makino was investigated. Methods and Results: Seedstocks were exposed to doses of gamma rays (5 Gy - 50 Gy), and subsequently planted in a greenhouse. After 30 days of sowing, the survival rates and growth decreased rapidly at doses above 20 Gy, while all individuals died at 50 Gy. The median lethal dose (LD₅₀) was 25.65 Gy, and the median reduction doses (RD₅₀) for plant height, number of stems, and fresh weight were 12.81, 9.32, and 23.26 Gy, respectively. Post-irradiation levels of malondialdehyde (MDA), peroxidase (POD), and chlorophyll in the aerial parts of the plant were quantified using spectrophotometry. Relative to the controls, the levels of MDA and POD increased, while the level of chlorophyll decreased at doses ≥ 10 Gy, indicating cellular damage. Conclusions: A dose of 20 Gy was found to be optimal for mutation breeding in C. officinale Makino.

• 대한간호학회지
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• 제6권1호
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• pp.72-79
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• 1976

Contemper nursing literature place much importance on human- centered and individualized care. Nursing research has related stress during hospitalization of adolescent patients to adaptation to a new environment, isolation from friends, limitation due to illness, over protection of parents and communication with member of the medical team. The investigator conducted this study in the hope that an understanding of adolescents responses to hospitalization, their perceptions, the kinds and levels of stress, and the relationships between stressors and individual characteristics would contribute to the improvement of adolescent patient care. The objective of the study was to obtain informations related to the adolescents psychological stress experience during hospitalization, specifically stress from interpersonal relationships and communication, isolation from the family, social or economic problems, illness and from the treatment environment and nursing care. An interview schedule adopted from Holmes and Rahe's Social Readjustment Rating Scale and selected items from Voicer's instrument on stress-producing events was used with 120 adolescent inpatients aged 13 to 18 years three general hospitals in Seoul during Aug. 10, to Sep. 30, 1975. 1. The sample consisted of 66 male and 54 female patients. Sixty-six percent were late adolescents, aged 16 to 18 years: 4% were early adolescents, aged 13 to 15 years. The primary cause for hospitalization was for orthopedic problems (35.8%). More than half of these (54.4%) were due to injury or accident. 2. Stress eclated to illness revealed the highest score (4.97), followed by stress related to treatment environment and nursing care (4.34) , isolation from family and social or economic problems (4.01) and interpersonal relationships and communication (3.96). 3. The perceived indifference of doctors and nurses was a serious cause of stress (mean=4.83). Fellow patients and visitors caused least stress (mean=2.06). 4. Discontinuation of education or unemployment were major stressful events (mean=4.71). Least stressful was isolation from the family (mean=3.47). 5. More than 94% of the respondents expressed fears related to body image (mean=4.97) 6. Within the category of treatment environment and nursing care, items related to restrictions because of treatment, discomfort because of treatment, inadequate explanation from nurses about procedures were rated as severe stress events (mean=4.6). Items related to the ward environment and to having a relative stay with them were seen by the group as less serious events (mean=3.7). 7. Stress related to interpersonal relationships and communication was correlated positively with female patients and those preferring passive activities. (P〈0.05) 8. Stress related to family problems was positively related to female and early adolescent patients (P< 0.05). Stress related to social problems was positively , elated to students and those preferring active pursuits (P< 0.05). 9. There were no correlation between the high stress related to disease and any of the characteristic items. (P> 0.05) 10. Stress related to treatment environment and nursing care was positively related of early adolescent and female and student patients. (P< 0.05) This group of hospitalized adolescents reported high level of stress related to treatment environment and nursing care, due to lack of consideration of normal growth and development and individual characteristics. The findings have important implications for the planning of effective, individualized, comprehensive nursing care of adolescents during hospitalization.