고도로 산업화된 오늘날의 시장경제 체제에 있어서 경제비용의 절감은 한 기업의 문제가 아니라 국가차원의 문제로까지 대두되고 있다. 물류부문의 개선을 통한 물류비용의 절감과 물류서비스개선 및 이윤창출은 국가경쟁력 측면에서도 매우 중요한 문제라 하겠다. 특히, 물류처리면에서 막대한 비중을 차지하고 있는 항만물류의 경우 그 어느 때보다 중요성이 강조되고 있다. 이러한 상황을 반영하듯이 우리 나라를 포함한 아시아 지역권내의 국가들은 수출입화물의 원활한 처리 및 막대한 경제적 파급효과를 발생시키는 항만물류에 적극적인 관심을 기울이며 투자계획을 수립하고 있다. 이러한 측면에서, 본 연구에서는 경쟁국간의 항만물류 현황을 조사하고, 실제 경쟁을 주도하는 구성요소를 파악하며, 파악된 구성요소를 사용하여 경쟁력을 평가해 봄으로써, 다양한 개선방안을 강구할 수 있는 계기를 제공하는 것을 연구의 목적으로 하였다. 연구의 내용은 크게 항만물류능력의 평가구조를 획득과정과 획득된 평가구조에 알고리즘을 적용시켜 해를 구하는 과정으로 나뉘어져 있다. 평가구조 획득은 선행연구를 통하여 도출된 평가세부속성에 KJ법을 적용시키는 절차를 따랐으며, 적용결과 평가의 구조는 대표속성을 중심으로한 다속성·다계층구조(Multiple Attributes·Multiple Hierarchy Evaluation Structure : MAMHES)로 구성되어 있음을 확인 할 수 있었다. 또한, 알고리즘적용 부문에서는 다속성·다계층구조를 평가할 수 있는 계층퍼지분석법(Hierarchical Fuzzy Process)을 도입하여 평가알고리즘을 완성하였다. 완성된 평가알고리즘을 우리나라를 중심으로 한 실제 경쟁국에 적용한 결과 국가별·항만별 경쟁력 및 순위를 획득할 수 있었다.
The objective of this study is the development of size discrete optimum design algorithm which is based on the GAs(genetic algorithms). The algorithm can perform size discrete optimum designs of space trusses. The developed algorithm was implemented in a computer program. For the optimum design, the objective function is the weight of space trusses and the constraints are limite state design codes(1998) and displacements. The basic search method for the optimum design is the GAs. The algorithm is known to be very efficient for the discrete optimization. This study solves the problem by introducing the GAs. The GAs consists of genetic process and evolutionary process. The genetic process selects the next design points based on the survivability of the current design points. The evolutionary process evaluates the survivability of the design points selected from the genetic process. In the genetic process of the simple GAs, there are three basic operators: reproduction, cross-over, and mutation operators. The efficiency and validity of the developed discrete optimum design algorithm was verified by applying GAs to optimum design examples.
개의 인공수정에 사용할 정자의 보존방법을 확립하기 위하여, 동결속도와 응해 온도를 설정하여 적절한 동결방법을 정립하고자 본 실험을 실시하여 다음과 같은 결과를 얻었다. 동결의 방법에 있어서는 액체질소의 표면으로부터 17 cm 높이에서 동결하는 -3/min의 동결속도로 실시하여 37에서 2분간 응해하는 방법이 가장 좋은 결과를 보였다. 생존성과 운동성에 있어서의 차이는 없지만 첨체의 intact한 비율은 약간 낮은 결과를 보였으며, 이의 보완을 위해, 액
본 연구는 최근 형질전환동물의 생산 및 복제동물 생산에 이용되고 있는 핵이식 기법을 시행할 때 재조합된 핵이식란의 활성화를 위해 널리 적용되고 있는 6-dimethylaminopurine (DMAP)의 활성화 효율과 근래에 제기되고 있는 단위발생란의 비정상적인 염색체 및 핵형에 대해 알아보고 적합한 활성화 유도물질을 찾고자 시행되어졌다. 도축장 유래의 난소에서 채란한 난자를 10% 거세한 수소혈청이 포함된 TCM-199배양에서 22시간동안 체외 성숙을
2000년 춘계에 한국 농촌지역인 충남 서산에서 대기부유분진(SPM)과 곰팡이포자의 관계에 대해 조사하였다. 부유분진의 농도는 1차 황사기간(3월 23-24일)에 199.8μg m-3, 2차 황사기간(4월 7-9일)에 249.4μg m-3, 비황사기간(5월 12-6일)에 98.9μg m-3으로 각각 나타났다. 2회의 황사기간들간에 부유분진 농도는 차이를 보였지만 5μm 정도의 입경 크기를
We tested the characteristics of the BOAO Medium Dispersion Spectrograph (MDS) such as the CCD capabilities, wavelength shift by gravity direction variation, slit illumination function and efficiency. Then we calculated the appropriate exposure time to obtain the given S/N ratio for several given magnitudes. Also the remaining problems to be improved were discussed.
Artificial insemination (AI) with frozen or cooled semen is widely used in commercial fields of cattle and pig. Little is known about characteristics of canine sperm after freezing or cooling. For both practical and commercial goal, the canine semen treated with cooling and freezing should be carried out to exam the fundamentals, including sperm motility, survivability and fertilizing capacity. The aim of this study, thus, was to identify the effects of extended exposure to 4 on canine semen by motility, survivability, acrosomal changes following different duration. Fifteen ejaculates collected by digital manipulation twice per week from 3 dogs (Shih-Tzu) were divided to 16 aliquots after adding Tris-egg yolk (TE) buffer formulated by our laboratory, and cooled from 37 to 4, by ramp rate of 0.6/min. Each sample was evaluated by their motility, survivability and the acrosomal status at 0h (control), 2h, 12h and 1 d~10 d, respectively. The motility of spermatozoa was graded to 6 levels using the modified method of Seager. The survivability of sperm was assessed using an epifluorescence microscope after Fert/Light (Mole-cular Probes Inc.) staining. To estimate the proportion of the spermatozoa of intact acrosome, 200 spermatozoa were assessed in randomly selected fields, using epifluorescence microscope after FITC/PSA (Sigma) staining. At 2 h after cooling, the motility of most spermatozoa were assessed to be grade 0 and 1. At 12 h, high number of sperm were in grade 0 to 1, however, it was significantly (P<0.05) lower than that of 2 h. From 1 d to 4 d, ~50% of sperm was assessed to grade 0 to 1. On day 7, a little sperm were in grade 0 to 1. No sperm showed motility on day 10. Sperm motility was rapidly reduced by the percent of 10% of grade 0 to 1. From 2 h to 6 h, the number of live sperm was 90% and the sperm chilled for 10 days lived>50%. Acrosomal intact of spermatozoa exposed to 4 for 2 h was 51%, supposed the sperm of control was 100%. Our results suggest that 1) this is easy to transfer and preservation for short periods 2) AI can be used by semen chilled for 6-Day.
The purpose of this study was to elucidate the effects of green tea catechins (GTC) on the lipid peroxidation and superoxide dismutase (SOD). GTC showed the high SOD activity, while significantly inhibited the peroxide value of linoleic acid (93%) and lipid petoacidation (84%) from rat liver microsomal fraction induced by Fe^(2+)/ascorbate system. The effects of GTC on the SOD and catalase activities, and lipid peroxidation after oral administration were investigated. GTC (50 mg/kg) significantly increased SOD (62%) and catalase activities (75%), while significantly inhibited the lipid peroxidation (52%) of rat liver microsome in a dose-dependent manner. These results suggest that GTC has the antioxidative effect which is related to the prevention of aging and cancer.
This study was carried out to elucidate whether sperm contain a factor inducing second polar body extrusion and to search for an effective collection method of the sperm factor Thus, sperm extract, dialyzed sperm-extract or liquid chromatographic fractions of sperm extract was microinjected into ovulated oocytes. And the microinjected oocytes were incubated for 24 hours to investigate about the extrusion of second polar body. The results obtained were as follows; 1. Sperm extract significantly increased the second polar body extrusion. 2. Sperm extract showed five major fractions at retention volumes (RVs) 1.25, 1.37, 1.84, 2.10 and 2.67ml after separation with Superose 12 column. These sperm extract fractions did not significantly increase the second polar body extrusion. 3. Dialyzed sperm-extract significantly increased the second polar body extrusion 4. Dialyzed sperm-extract showed three maior fractions at RVs 1.88, 2.14 and 2.77ml after separation with Superose 12 column. Of these fractions, the fraction RV2.14 significantly increased the second polar body extrusion. In conclusion, sperm extract contained a factor inducing the second polar body extrusion and the factor was contained largely in fraction RV2.14 after dialysis and liquid chromatographic fractionation of sperm extract.
This study was conducted to investigate most effective the optimum lime content for lime-clay modification. To achieve the aim, characteristics of compaction and compressive strength were tested by adding of 0, 5, 10, 15 and 20% lime (Hydrated lime) of dry weight of the clay. Distilled water was added 10, 15, 20 and 25% of dry weight of lime-clay mixture. In this test, the compressive strength of the specimens was measured according to the following curing period : 7, 21, 28, 35 and 49 days. The results are as follows. (1) As lime additive increased, the optimum moisture content of lime-clay mixture was increased and the maximum dry density was decreased. (2) The soil mixture of 20% of the moisture content and 10% of lime additive was shown the maximum compressive strength. (3) As curing period longer, the compressive strength was increased but after 21 curing days, the increasing rate of compressive strength was low as compared with earlier its value. (4) In the range of 20% of the moisture content, compressive strength of mixture of 10% lime additive increased twice compared with that of mixture of 0% lime additive. (5) All of the lime-clay are possible to use for an sub-base material and 20% of moisture content of lime-clay mixture is possible to use for a base material.
Symbiotic stars are known as binary systems with both cool and hot components with enshrounding nebulous gas. The cool component, M-type giant, is presumably loosing its mass into a hot white or main sequence companion star through the inner Lagrangian point. The lines emit from the ionized nebulous region around the hot star while the mass loss or accretion activity is believed to be the main cause of sudden variation of the continuum and line fluxes. We selected 17 symbiotics for which the emission line fluxes were measured from the IUE SWP, LWR data, to find variability of spectrum. We also investigated the periodic variation of emissions or eclipsing effect from the IUE lines. All of our symbiotics show very high electron densities in the emission regions. For other optical symbiotics, the observations had been carried in 1999 with BOAO mid-resolution spectrometer. We classified symbiotics based on their outburst activities, or emission line characteristics, i.e., OVIλ6830.TheOVIλ6830 OVIλ6830.TheOVIλ6830 emission lines are also found in S-type symbiotics, which have been known as charateristics of D-types.
본 연구에서는 중학교 및 고등학교의 지구과학 내용에 대한 멀티미디어 학습 프로그램을 개발하였다. 개발된 학습프로그램은 HTML 형식이며 텍스트, 사진, 그림, 동영상 등 다양한 내용물들로 구성되어 있다. 그리고 크게 학습 내용, 용어사전, 생활 과학, 탐구 활동, 영상 자료, 형성 평가 등 6가지 데이터베이스 요소들로 구성되어 있다. 본 연구에서 개발된 멀티미디어 학습 프로그램을 교사와 학생들에게 적용해본 결과 긍정적인 반응을 보였다. 이 프로그램은 현재 공주대학교 과학교육연구소 인터넷 흠페이지에서 무료로 제공하고 있다.