• Progress in Superconductivity
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• 제3권1호
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• pp.49-55
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• 2001

Josephson junction arrays were fabricated by DC magnetron sputtering, self-aligning and reactive ion etching technique. The Al native oxide, formed by thermal oxidation, was used as the tunneling barrier of Nb/$Al-A1_2$$O_3$Nb trilayer. The arrays have 2,000 Josephson junctions with the area of $14\mu\textrm{m}$ $\times$ $46\mu\textrm{m}$. The gap voltages were in the range of 2.5 ~2.6 mV and the spread of critical current was $\pm$11~14%. When operated at 70~94 ㎓, the arrays generated zero-crossing steps up to 2.1~2.4 V. To improve transmission of microwave power and prevent diffusion of oxygen into Nb ground-plane while depositing $SiO_2$dielectric, we applied a plasma nitridation process to the Nb ground-plane. The microwave power was well propagated in Josephson junction arrays with nitridation. The difference in microwave transmission 7an be interpreted by the surface impedance change depending on nitridation.

• Applied Microscopy
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• 제27권4호
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• pp.417-432
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• 1997

The structures of the fertilized egg envelope in three species of cichlidae, golden severum (Cichlasoma severum var.), convic cichlid (Cichlasoma nigrofasciatum) and discus (Symphysodon aequifasciatus) were investigated by routine light and electron microscopies. The fertilized eggs of all three species were of the non-transparent, ellipsoidal, adhesive and non-floted type. The egg envelopes have a single micropyle, which is thought to the pathway of sperm in the area of the animal pole. In golden severum, an outer surface of egg envelope was covered by a reticular layer, that of convic cichlid was covered by an amorphous reticular layer and that of discus was covered by a branched reticular layer. The fertilized egg envelopes consisted of two distinct layers, an adhesive outer layer and an inner layer, consisted of lamellae alternating with interlamellae of lower electron density, in all three species; an inner layer of golden severum was $15\sim17$ layers, that of convic cichlid was $14\sim16$ layers, and that of discus was $18\sim19$ layers.

• Applied Microscopy
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• 제28권2호
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• pp.237-253
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• 1998

The structures of the fertilizedegg envelope in threespecies of cyprinidae, leoparddanio (Brachydanio frankei), cherry barb (Barbustitteya) and white cloudmountain fish (Tanichthys albonubes) were investigated by light and electron microscopy. The fertilized eggs of all three species have colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropylewhich is thought to the pathway of sperm in the area of the animal pole. Also, an outer layersof both cherry barband white cloud mountain fish areadhesive types, but in that of leoparddanio has non-adhesivetype. In leopard danio, an outer surface ofegg envelope is covered by mushroom-likestructure, that of cherry barb is arranged by button-like structure, and that of white cloud mountain fish isarranged by rod-likestructure. Inboth leopard danioand cherrybarb, the eggenvelopes consist of three distinct layers; an outer layer, a middle layer and an inner layer, and that of white cloud mountain fish hastwo layers. An innerlayer of egg envelopein leopard danio consist of 10 layers, cherry barb has 8 layers, and white cloud mountain fish has $5\sim6$ layers.

• The Korean Journal of Ecology
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• 제22권1호
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• pp.7-11
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• 1999

환경오염과 관련하여 제안된 미국자리공의 분포확대가 토양의 산성화와 나아가서는 사막화를 가져온다는 가설을 실험적으로 확인하여 그 실체를 밝히고자 울산과 청주를 대상으로 미국자리공 군락에서의 근권 토양산성도를 측정하였다. 측정한 장소 중에서 청주의 부모산을 제외한 울산의 신선산, 돗질산 그리고 봉대산은 pH가 5.0 이하로 5.25와 5.33의 범위에서 변화한 청주의 부모산의 근권토양보다 강한 산성을 나타내었다. 그러나 봉대산을 제외하고는 식물체의 축을 중심으로 수평적으로나 수직적으로나 근권산성도에 유의차가 보여지지 않았다. 반면, 울산의 봉대산에서는 뿌리를 중심으로 수평적으로는 근권산성도가 변하지 않았지만 지표면 토양이 그 아래 토양보다 높은 산성도를 나타내었다. 이것은 일반적인 토양산성도의 패턴과 반대 현상으로, 지표면이 더욱 산성이라는 것은 지상환경의 오염, 즉 대기오염과 관련이 있다는 것을 나타내 주고 있다. 또한 이러한 사실은 미국자리공의 생장과정에서도 근권 토양산성도가 거의 변하지 않았던 모델실험 결과와도 잘 부합되었다. 따라서 미국자리공이 토양을 산성화시킨다는 가설은 다시 한번 고려되어야 할 것이다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 하계종합학술대회 논문집(2)
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• pp.459-462
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• 2004

In this paper, we present a reducing power consumption of a scheduling for module selection under the time constraint. A a reducing power consumption of a scheduling for module selection under the time constraint execute scheduling and allocation for considering the switching activity. The focus scheduling of this phase adopt Force-Directed Scheduling for low power to existed Force-Directed Scheduling. and it constructs the module selection RT library by in account consideration the mutual correlation of parameters in which the power and the area and delay. when it is, in this paper we formulate the module selection method as a multi-objective optimization and propose a branch and bound approach to explore the large design space of module selection. Therefore, the optimal module selection method proposed to consider power, area, delay parameter at the same time. The comparison experiment analyzed a point of difference between the existed FDS algorithm and a new FDS_RPC algorithm.

• 분석과학
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• 제15권3호
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• pp.287-299
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• 2002

인천연안지역 표층퇴적물의 PCBs 잔류농도는 우리 나라의 다른 연안지역 보다 비교적 낮은 농도로 검출되었고, 전지역에 걸쳐 Aroclors 혼합표준액 (1016+1232+1248+1260)과 유사한 패턴으로 배출되었으며, 염소조성비율 변화에 따라 A(Kanghwa), B(Yellow) 및 C(Jangdo) 등 3개의 지역군으로 분류되었다. 또한, 외해에 근접한 B 지역은 2, 3 염화물이, 매립지 침출수 처리수가 방류되는 C지역은 7, 8염화물이 다른 지역에 비해 높은 염소 조성비율을 나타내는 것으로 조사되었다. 연구대상지역 주상퇴적물의 PCBs 잔류농도는 강화수로에서 1.60~3.00 ng/g, 장도수문에서 0.34~9.20 ng/g으로 나타났으며, 두 지역 모두 하부층에서 상부층으로 올라갈수록 농도가 증가하는 경향을 나타내었다.

• 한국조경학회지
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• 제19권3호
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• pp.98-127
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• 1991

This study has purposes of not only establishing urban community park systems and index for designing the parks, which were reviewed from Korean urban community parks, but also finding the relation and the enticing area according to the catchment of urban community parks. This paper suggested two hypotheses. a. The strength of the catchment force of urban community parks can be represented to the usetimes or visitors of the parks, related with the distance for reaching the parks. b. The strength of the catchment force of the parks can be found to express the idiosyncratic one according to the qualitative differences between the parks. The suggested hypotheses were testified from Korean 9 urban community parks in Seoul., Suwon, Chongju, and Chonan, conforming the multiregressions of the variables, distance and usetime in the case of the first hypothesis, scale, the ratio of green space, population, the budget for the park, facilities and the function of the city in the case of the second hypothesis. All the correlation coefficients of usetime with distance except one were over about 0.8. The second hypothesis was testified with multiregressions for the variables. Therefore, the enticing area could be divided into three zones ; a closed aone to parks, a good used aone for parks, a possible zone for using parks.

• 한국환경복원기술학회지
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• 제4권1호
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• pp.67-79
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• 2001

According to the new general movement of ESSD in Korea, the role, background, and subjects, etc. of Ecological Restoration Area were studied to find out the way for this area to be settled as one kind of industry. Questionnaire and literature study were carried out to understand and to find out the way of the area settlement with the conceptual and practical definition of it. The related sub-areas studied were 1. regulations and standards including design and construction 2. researches and developments around the area 3. related curriculums applying in the educational organizations 4. present situation of the industry. Followings are the results of this study and several proposals for the area to be settled in Korea with the other related areas. 1. The boundary of Ecological Restoration could be defined as the concept of preservation(or conservation) and restoration of the ecosystem with ecological planting - including the restoration strategies for the areas of slope, artificial foundations, watersides and wetlands, with in bio-diversity and eco-forests for these areas. 2. It seems that the more investments needed for the elaborate and professional techniques to be developed for the design and construction works to the contrary that the base of this area be matured already in the several sub-areas. 3. For the successful work of Environmental Restoration, defining the new industrial branch -independent from existing construction industry- is recommended through the law system under the control of the Ministry of Environment. It will be better if professional officer system in governmental organization could follow up this. 4. Educational organization and Technical expert qualifying system to train the Ecological Restoration Professionals should be induced for the effective practice of the area.

• Applied Microscopy
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• 제26권3호
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• pp.277-291
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• 1996

The structures of the egg envelope in fertilized eggs of three species of characidae, head and tail light fish (Hemigrammus ocellifer), black tetra (Gymnocorymbus ternetzi), and buenos aires tetra (Hemigrammus caudovittatus) were studied using light and electron microscopes. The fertilized eggs in all species were colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropyle resembling the pathway of sperm in the area of the animal pole. The micropyle was surrounded by protruded lines of the egg envelope in a radiated form. Egg envelopes of fertilized eggs in both head and tail light fish and buenos aires tetra consisted of three distinct layers; an outer layer, a middle layer and an inner layer. And that of blacktetra consisted of two layers; an outer layer and an inner layer. Also, an outer layers of both head and tail light fish and black tetra were adhesive types but, in that of buenous aires tetra was non-adhesive type. An outer surface of egg envelope in black tetra was arranged by pores regularly. In that of head and tail light fish and buenos aires tetra have a rough side. An inner layer of egg envelope in fertilized eggs consisted of lamellae alternating with interlamellae of lower electron density; an inner layer of fertilized eggs in head and tail light fish consisted of three layers, that of black tetra was four layers, and that of buenos aires tetra was five layers.

• 한국환경복원기술학회지
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• 제4권1호
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• pp.98-109
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• 2001

This study aimed to investigate the effect of revegetation technique for water attacking point using waterlogged prevention frame revetment. In this study, we evaluate frame revetment stability, water quality, plant growth and ecological and envirnomental changes in Mooshim streamside landscape. The results are as follows; 1) The waterlogged prevention frame revetment appeared to be stable despite of two big floods. The materials used for the revetment were not eroded on the water attacking point. Thus, we confirmed the effect of scour prevention of the frame work. 2) The effects of the frame revetment on the water quality appeared to be good for the surrounding environment. Dissolved Oxygen(DO) was higher about $0.4{\sim}0.6mg/{\ell}$ at the frame revetment than that of the main stream flow. pH value was lower about 0.4~0.5. Electric Conductivity(EC) showed lower about $0.8{\sim}1.1{\mu}s/cm$. at submersion prevent frame than the low-flow of the stream. Turbidity was lower about $0.6{\sim}1.2mg/{\ell}$. 3) As the effects on ecological and environmental conditions, we discovered a number of carassius auratus and Zacco platypus in the frame revetment area. Also, sympetrum balteata, coenagrionidae was observed frequently. 4) The plant growth did not appear to tumble or wither despite of two big floods. The visual rating of plant growth was evaluated as medium (around 5 point) 5) The landscape analysis derived four factors(i.e. the harmony, the variation, the flexibility and the provincial characteristics) from the factor analysis.