Study on Leaf Production of Angelica acutiloba by Mulching with Polyethylene Film

Choi,Seong-Kyu,Yun,Kyeong-Won,Chon,Sang-Uk,Seo,Young-Nam,Seo,Kyoung-sun,Kwon,Byung-Sun 한국자원식물학회 2003 Plant Resources Vol.6 No.3

This study was conducted to produce effectively more leaves of Angelica acutiloba through year-round production system by using various mulching materials and polyethylene(PE) tunnel. Soil temperature by covering treatment was higher in PE mulching and PE tunnel than in rice straw mulching, especially showing the highest temperature in PE tunnel from April through May. Water content of soil was higher in PE mulching than in non-mulching. Leaf production of Angelica acutiloba through year-round production showed the highest in PE tunnel and root production in PE mulching. These results suggest that leaf production of Angelica acutiloba can be maximized through PE tunnel cultivation system.

Effect of Activated Charcoal on Growth of Zingiber mioga ROSC

Choi,Seong-Kyu,Yun,Kyeong-Won,Chon,Sang-Uk,Seo,Young-Nam,Seo,Kyoung-Sun,Kwon,Byung-Sun 한국자원식물학회 2004 Plant Resources Vol.7 No.2

Activate charcoal (AC) can be utilized as a soil conditioner in agricultural crop areas. This study was conducted to investigate the effect of AC on growth and yield of Zingiber mioga ROSC as affected by different amounts of AC. The results obtained are summarized as follows. Growth characteristics including plant height and leaf length were the highest when activated charcoal added with 10-30%, suggesting that optimum amount of activated charcoal was ranged from 10 to 30%. Growth and enlargement of the root were improved by 10% AC with higher rhizome length and weight.

水球選手의 無酸素性 파워에 관한 硏究

최선용,이병두,이규성 韓國體育大學校附屬 體育科學硏究所 1990 韓國體育大學校附屬 體育科學硏究所論文集 Vol.9 No.1

The purpose of this study was to analyze the Anaerobic Power and Blood lactate concentration of Water-polo players (University and high school) in incremental load exercise. Subjects were selected from Korean National College of Physical Education and Seoul High School, whose careers had been 3 to 4 years in water-polo. The study utilized isokinetic muscle contraction test and Wingate test by Cybex-Ⅱ and computerized bicycle-ergometer. The results of the study were as follows : 1. Anaeroble powers of water-polo players of the university and high school respectively were 57.62±3.99%, 48.8±8.74% in Extensor and were 45.5±7.30, 39.0±6.96% in Flexor by Cybex-Ⅱ. 2. Anaerobic powers between two groups by wingate test were 57.62±3.99KPM/S in College group, 50.58±3.17PM/S in High School group with a mean power and 68.49±6.19KPM/S in College group, 61.32±3.64KPM/S in High School group with maximal state. But It was a statistically significant differences (p <.001) between two group. Fatigue index of water-polo players of College and high school saparately were 31.14±2.36% and 37.96±4.56%. These data showed a statistically significant difference (p<.001). 3.Maximal blood lactate concentrations between College players and High School Players were 8.6±0.73mmoles/1 and 7.4±1.88 mmoles/1, revealing a statistically significant difference (p< .01) in 3 minute recovery. And recovery ratio respectively are 64.4%, 62.9% in not statistically significant difference at 10 minute of recovery. 4. Correlation coefficients between endurance ratio of extensor, flexor and maximal blood lactate respectively showed 0.872, 0.804 for water-polo player of univ. and high school. Between means, maximal values of wingate test and maximal blood lactate are 0.849, 0.860.

殘留應力을 考慮한 鎔接材의 疲勞龜裂 進展擧動에 關한 硏究

최병기,이을호,국중민,기준호,임선빈,정장만 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1

The effect of welding residual stress on the initiation and propagation of fatigue crack is investigated so as to study the fatigue behavior in welding residual stress field. Especially, the relation between welding residual stress and fatigue crack opening behavior is investigated and the redistribution of residual stress as a fatigue crack propagates is examined. Following results are obtained. 1) In case of the load range is constant, as the stress ratio is changing to 0.1, 0.33, 0.5 the propagation life is constant but the growth life decreases. And than, when maximum load or minimum load is constant, as the stress ratio increases the growth life and propagation life increase. 2) The fatigue crack propagations rate da/dN appears to accelerate when the stress intensity factor range ΔK is less than 15MPa-m^1/2. 3) The residual stress that is appeared by welding decreases after cutting. 4) Fatigue crack propagation ratio is affected by tensional and compressible residual stress at the initial time, but it's similar to the original in the more than 20mm of crack length.

전남지역 고등학생의 통일의식에 관한 조사연구

최영철,손병선 순천대학교 과학교육연구소 2001 科學과 敎育 Vol.9 No.-

The aim of this paper is to make a useful materials in forming the right view of unification of high school students, and to suggest the ways of the education of unification of them by looking into the consciousness of korean unification of high school students. This paper examined the consciousness on the peace in Korea, the democratic citizenship, the status of understanding of North Korea, and the national community. Using data collected in 2001, this paper finds the followings: First, viewing on the peace in Korean peninsula, most of students(76.6%) answered to want the peaceful coexistence of North and South. In addition, most of students wanted the gradual and peaceful unification and objected the unification by military force or by any other coercive methods. Second, however, the concern on national unification was very low. Only 42 percent of boy students had the concern about unification, while that of girl students was 30 percent. Therefore we can conclude that boy students have more positive and progressive views on the unification problem. Third, 63.5 percent of students think that the education of unification and on North Korea is objective and fair. This response may be caused by historical event like North-South summit held on June 15, 2000. Fourth, low percent of students(32%) answered that the most necessary work in reestablish national community between North and South is the exchange of people and resources. We can infer that the unification education can be improved as the following ways. First, the students should be taught to have more concern on unification. Second, the education of unification have to focus on understanding the circumstances of North and South Korea objectively. Third, the education of unification should be done to establish the consciousness of the national community.

EC 통상정책의 결정체제 및 특징

최병선 서울대학교 국제지역원 1992 국제지역연구 Vol.1 No.1

1987년 단일 유럽법의 시행 이후 EC는 단일시장 형성의 차원을 넘어서서 정치적 통합체로 의 발돋움을 계속하고 있다. EC의 이러한 노력은 급변하는 국제정치경제질서에 EC가 보다 적극적으로 대응하기 위한 노력의 표현이기도 하지만 다른 한편으로 이러한 EC의 웅장한 시도는 앞으로의 세계 정치경제질서에 중대한 변화를 예고하는 것이기도 하다. 이 논문은 이와같이 급변하고 있는 EC의 정책 가운데 우리와 관련이 깊은 EC의 대외공동통상정책의 정책결정 메카니즘과 정책결정과정, 그 결과로 나타나는 EC의 대외공동통상정책의 특징을 파악하려는 목적을 가지고 있다. EC의 대외공동통상정책은 EC회원국 사이의 정치적 타협자 협상, 또한 GATT체제 하에서의 EC와 제3국 사이의 정치적 타협과 협상의 산물이라고 할 수 있다. 그 결과 EC의 통상정책은 앞으로도 상당기간 동안 보호주의적인 색채, 산업정책적 색채를 강하게 띠게 될 것으로 예상된다. 그러므로 EC의 통상정책에 대한 연구는 단지 통상정책의 차원에서만이 아니고 EC단일시장의 형성과정, 그것의 진전속도, 방향 및 구체적 내용, EC경쟁정책의 적용 강도, 산업정책 및 기술개발정책의 운용방향, 각종의 사회적 규제(환경, 소비자안전보호등)에 대한 정견 등 다각적 측면에서 접근해야 할 필요가 있다. 1 Since the enactment of the Single European Act in 1987 the EC has stepped up it unifying efforts toward even establishing a political union. Such a move not only represent the EC's aggressive response to the rapidly changing international political economy, but forebears a fundamental change in it. This article aims at analyzing the current state of the internal market and the process of integrating and harmonizing commercial policies among the EC countries with disparate political and economic interests. In particular, this paper will examine the current structure and the general patterns of decision-making in the EC, and then stress the characteristics of the EC's commercial policy which has to be made in such process and the complicated decision-making structure. The EC's commercial policy is in essence the product of political wheeling and dealin both among the 12 member countries and between the EC and the numerous third countries. As a result, the EC's trade policy tends to be protectionistic and it will be increasingly. so in the future. Of course, its strength will depend on the successful completion of the Uruguay Round trade negotiations. Nonetheless, the EC's commercial policy tends to take on the feature of industrial policy, as member countries strive to maintain their traditional competitive position not only vita-a-vis the world but within the enlarged EC market. In view of the above, to conduct a proper analysis and to reach a more accurate understanding of the shaping of the EC's commercial policy in the future, it is necessary to focus not only on the EC's commercial policy ·itself, but more extensively on the process speed, direction and the contents of single market formation, and on the EC's competition policy, industrial policy, technology development policy and even various sorts of social regulatory policies (including environmental protection and consume. protection).

평균 유효 세율의 결정 요인에 관한 연구

宣炳完,崔康得 全北大學校 1994 論文集 Vol.38 No.-

A number of empirical studies have used effective tax rate(ETR) measures calculated from financial statement information to examine the relations between taxes, firm decisions, and firm characteristics. Studies using the average effective tax rate to measure corporate tax (dis) advantage have played a critical role in tax legislation. Recent research, however, has questioned the effectiveness of the ETR for this purpose. Previous research on corporate ETRs identified three important findings : (1)ETRs vary across firms(industries), (2) ETRs change over time, and (3) variances of ETRs differ across industries. These findings were explained solely in terms of cross-sectional and intertemporal differences in tax preferences. All other factors were implicitly assumed to be unimportant. This paper challenged the existing explanation by deriving the ETR as a function of the marginal tax rate and two variables : tax preferences and (pre-tax accounting)income. The model demonstrated how changes in the ETR can occur under two alternative assumptions about the relationship between tax preferences and income. Specifically, when tax preferences and income are perfectly correlated, the model showed that changes in the ETR are caused solely by changes in tax preferences. In the absence of perfect correlation, however, the model indicated that both tax preferences and income are capable of causing the ETR to change.

Ca 첨가한 AZ91 마그네슘 합금 용탕의 산화거동

최병호,유봉선,박원욱,박익민 대한금속재료학회 2004 대한금속·재료학회지 Vol.42 No.8

The effects of Ca addition on the liquid oxidation behaviors of AZ91 alloys have been investigated. The oxide layers formed on the molten Ca-containing AZ91 alloys were investigated by using scanning electron microscope and Auger electron spectroscopy in order to elucidate the effect of Ca additions on the ignition and burning of the molten alloys. The thermogravimetric measurements indicated that Ca-containing AZ91 alloys have good oxidation resistance. AES depth analysis revealed that the oxide layers on the molten Ca-containing AZ91 alloys consisted of several layers; the outer layer mainly consisted of CaO and the inner layer was mainly a mixture of CaO-MgO and Al₂O₃. The formation of protective CaO in the oxide layer was directly responsible for improved oxidation resistance of the Ca-containing AZ91 alloys.

Trichloroethylene의 대사 및 간독성에 diethyldithiocarbamate가 미치는 영향

최병선,박정덕,홍연표 大韓産業醫學會 2002 대한직업환경의학회지 Vol.14 No.3

목적 : 이 연구는 TCE 급성 폭로시 TCE의 대사 및 급성 독성작용과 diethyldithiocarbamate(DDTC)가 TCE의 독성 작용에 미치는 영향을 밝히기 위하여 시행하였다. 방법 : Sprague-Dawley계 수컷 쥐를 DDTC로 전처리한 군과 saline으로 처리한 군으로 나누고, 여러 농도(600, 1,200, 2,400 ㎎/㎏ body weight)의 TCE을 경구투여한 후 12시간에서 체내 각 조직의 TCE 및 TCE 대사물의 농도와 조직병리학적 변화소견을 관찰하였다. 결과 : CYP2E1 효소는 DDTC를 전처리 한 군에서 현저하게 감소하였으며, TCE만 투여한 군에서는 투여량이 증가함에 따라 CYP2E1이 유의하게 증가하여 TCE이 CYP2E1을 유도하는 것을 알 수 있었다. TCE와 TCEOH이 체내 농도는 간에서 가장 높았고, TCA의 농도는 혈액에서 가장 높게 나타났다. DDTC로 전처리한 군에서는 TCE 체내 농도가 TCE만 투여한 군보다 현저하게 높게 나타났고, TCA와 TCEOH의 농도는 현저하게 감소하여, DDTC가 TCE의 대사를 현저하게 억제함을 알 수 있었다. 조직병리학적 소견으로 볼 때, TCE 투여군에서만 간 중심소엽에 국소적인 괴사가 관찰되었고, DDTC 전처리후 TCE 투여군에서는 아무런 임상소견도 관찰할 수 없었다. 결론 : DDTC는 TCE에 의한 급성 간독성에 보호효과가 있는 것으로 나타났는데 이는 DDTC가 TCE의 대사를 억제하기 때문인 것으로 생각된다. Objectives: The purpose of this study was to evaluate the trichloroethylene(TCE)metabolism, acute toxicity, and the effects of diethyldithiocarbamate(DDTC)on the acute toxicity in TCE-intoxicated rats. Methods: TCE was administered orally at doses of 600, 1,200 and 2,400 ㎎/㎏ of DDTC. 12 hours after administration of TCE, the concentrations of TCE. trichloroacetic acid (TCA) and trichloroethanol(TCEOH) in the blood and solid organs, and the histopathological changes in each organ were examined. Results: The level of CYP2E1 markedly decreased in the DDTC-pretreated groups. The CYP2E1 content in the TCE-treated rats increased in a dose-dependent manner. The concentrations of TCE and TCEOH, than the rats pretreated with saline. These findings indicated that CYP2E1 was important in the metabolism of TCE. From the histopathological findings, centrilobular necrosis was observed in the livers of the TCE-treated rats, but no significant change was found in those rats pretreated with DDTC. Conclusions: DDTC is considered to be effective in protecting TCE-induced hepatic damage because it inhibits the TCE metabolism.

우리나라 규제개혁정책의 핵심과제와 쟁점

崔炳善 서울대학교 행정대학원 1997 行政論叢 Vol.35 No.2

20년 가까운 역사를 가진 우리나라의 규제완화 및 개혁과정에서 우리는 어떤 정책학적, 행정학적 시사점을 얻을 수 있을 것인가? 이 글에서 필자는 최근 「행정규제기본법」제정을 계기로 규제개혁 추진체계 전반에 걸쳐 제기된 많은 문제의식과 논의 가운데 학문적으로 깊이있게 검토할만한 가치가 있는 핵심적 논쟁사항들을 필자의 시각에서 논리적으로 일관성있게 정리해 보려고 하였다. 이 글에서 부각시키고 있는 사항. 즉 ① 민간인주도 규제개혁의 한계성, ② 규제개혁의 목적에 대한 재검토 필요성, ③ 규제개혁에 대한 국민들의 지지확보를 위한 전제, ④ 규제완화와 조직개혁의 관계, ⑤ 규제와 부정부패의 관계 등은 앞으로 규제개혁 추진체제를 개선함에 있어 심도있게 검토해야 할 사항이기도 하지만, 우리나라의 규제개혁정책에 관한 중요한 연구주제가 될 수 있을 것으로 기대한다.