• Title/Summary/Keyword: Passage

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A Theoretical Study on the Wildlife Passage for Connecting Fragmented Habitat(I)- In the case of Wildlife Passage Types and Design Process (분절된 서식처의 연결을 위한 생태이동통로에 관한 이론적 연구(I) - 유형구분 및 조성절차를 중심으로 -)

  • 김귀곤;최준영
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.2
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    • pp.293-307
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    • 1998
  • This study has been divided into two parts, 1) literature review and 2) a case study. Based on literature review and case studies found in Korea and abroad, this study aimed at classifying wildlife passages and establishing their development procedures in order to establish a theoretical ground for the development of wildlife passage as a way to link habitats that have been fragmented by the construction of roads and other developments. The results of the literature review are as follows : 1) Impact of road construction on surrounding ecological environment is found in various aspects. Along with damage of habitats as direct impact, decrease of biodiversity and simplification of species due to limited breeding and movement are cited as possible indirect impact. 2) In order to lessen the impact generated from fragmented habitats, various types of wildlife passage are being developed in Europe and are showing positive results. 3) In Korea, interests on animal passages have been rising recently. The ministry of Environment and local authorities are establishing development plans for the passages. However, practical materials on the usefulness of adoped methods are not available.4) In order to create an effective wildlife passage, decisions have to be made first on basic factors of planning and designing such as ecosystem rehabilitation methods and surveys on wildlife movement routes and habitat environment. Based on this, in a planning and designing stage, the location and type of a passage, size and measures to attract animals and prevent a collision need to be finalized. This should be followed by a series of process of maintenance, management and monitoring after the development. Based on the results of a theoretical study to develop an wildlife passage, Part 2 of this study deals with the results of an experiment through a specific planning and design that includes a process of ecological surveys, site selection, type selection, ecosystem infrastructure, planting design and construction details on an actual study area and presents them as a model project.

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A Study on the Exhaust Gas Recirculation in a MILD Combustion Furnace by Using the Coanda Nozzle Effect (MILD 연소로에서 Coanda 노즐 효과를 이용한 배기가스 재순환에 관한 연구)

  • Ha, Ji Soo;Shim, Sung Hoon
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.12
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    • pp.967-972
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    • 2013
  • A MILD (Moderate and Intense Low oxygen Dilution) combustion, which is effective in the reduction of NOx, is considerably affected by the recirculation flow rate of hot exhaust gas to the combustion furnace. The present study used the MILD combustor, which has coaxial cylindrical tube. The outside tube of the MILD combustor corresponds to the exhaust gas passage and the inner side tube is the furnace passage. A numerical analysis was accomplished to elucidate the characteristics of exhaust gas entrainment toward the inner furnace with the changes of coanda nozzle geometrical parameters, nozzle passage gap length, nozzle passage length, nozzle angle and expansion length. The optimal configuration of coanda nozzle for the best entrainment flow rate was gap length, 0.5 mm, expansion angle, 4o and expansion length, 146 mm. The nozzle passage length was irrelevant to the exhaust gas entrainement.

Causes and Effects of Conflict Arising from Public Pedestrian Passages in an Apartment Complex - Based on a Survey of Residents living in an Apartment Complex - (공동주택 단지 내 공공보행통로의 갈등 요인과 영향 - 공동주택 거주민의 인식조사를 바탕으로 -)

  • Lee, Seung-Ji
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.12
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    • pp.95-102
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    • 2018
  • The purpose of this study is to investigate the causes of conflict that arise from public pedestrian passages installed in apartment complexes through a survey of residents' perceptions and to investigate the effects on the satisfaction with and necessity of the public pedestrian passage. This has significance as a preliminary research into determining solutions to conflict related to public pedestrian passages that are open spaces, accessible 24 hours a day to pedestrians including people who live outside of the apartment complex. The result of the residents' perception survey showed that there is conflict due to the public pedestrian passage. The main problem was the noise-related variables. While management and safety variables were also perceived as problems, privacy and ownership infringement variables were not. These problems were reduced to four factors through a factor analysis: unfavorable incidents, environment management, ownership infringement, and safety crimes. Analyzing the effects of the above factors on the satisfaction with the apartment complex, satisfaction with the public pedestrian passage and the necessity of the public pedestrian passage, demonstrated that the unfavorable incidents factor influenced all the variables. The safety crimes factor, which is an extended concept of the unfavorable incidents, affected both the satisfaction and necessity of the public pedestrian passage. The ownership infringement factor was found to affect the satisfaction of the public pedestrian passage only, and the environment management factor did not affect all the variables. In planning and managing public pedestrian passages, avoiding incidents and crimes should be considered as a priority to increase the satisfaction of residents and solve conflicts.

Evaluation of virulence reversion of an attenuated porcine epidemic diarrhea vaccine strain by serial passages in suckling piglets

  • Da-Jeong Kim;Seung-Chai Kim;Hwan-Ju Kim;Gyeong-Seo Park;Sang Chul Kang;Won-Il Kim
    • Korean Journal of Veterinary Service
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    • v.46 no.3
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    • pp.193-202
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    • 2023
  • Porcine epidemic diarrhea is an infectious intestinal disease caused by the porcine epidemic diarrhea virus (PEDV). Especially, when suckling piglets are infected, the mortality rate is close to 100%. PEDV is classified into G1 and G2 types based on genetic differences. The G2 type PEDV outbreak in the United States in 2013 was highly pathogenic and contagious, and it has spread worldwide and caused continuous economic losses. Most commercial vaccines used are G1 type vaccines, and existing vaccines do not fully protect piglets due to genetic differences. In this study, we evaluated the safety of the newly developed G2 type attenuated HSGP vaccine strain by inoculating it into piglets and testing whether the vaccine virus spreads to the non-vaccinated, negative pigs and whether the vaccine reverts to its virulence during serial passage experiments. Each experiment lasted for 7 days for each passage, and fecal viral titers, clinical symptoms, and weight gain were measured daily. After the experiment, necropsy was performed to measure intestinal virus titer and pathological evaluation. As a result of the first passage, no transmission of the vaccine virus to negative pigs co-housed with vaccinated pigs was observed. In addition, after four consecutive passage experiments, the clinical symptoms and small intestine lesions were gradually alleviated, and no virus was detected in the feces in the fourth passage experiment. Therefore, it was concluded that the vaccine was safe without virulence reversion in accordance with the guidelines of the current licensing authority. However, further studies are needed on the genetic changes and biological characteristics of the mutant virus that occur during successive passages of the attenuated vaccine since the replication and clinical symptoms of the virus increased until the third passage during successive passages of the vaccine virus. Based on this study, it was concluded that virulence reversion and safety evaluation of attenuated vaccines through serial passage in target animals can be useful to evaluate the safety of attenuated viruses.

Passage Planning in Coastal Waters for Maritime Autonomous Surface Ships using the D* Algorithm

  • Hyeong-Tak Lee;Hey-Min Choi
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.3
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    • pp.281-287
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    • 2023
  • Establishing a ship's passage plan is an essential step before it starts to sail. The research related to the automatic generation of ship passage plans is attracting attention because of the development of maritime autonomous surface ships. In coastal water navigation, the land, islands, and navigation rules need to be considered. From the path planning algorithm's perspective, a ship's passage planning is a global path-planning problem. Because conventional global path-planning methods such as Dijkstra and A* are time-consuming owing to the processes such as environmental modeling, it is difficult to modify a ship's passage plan during a voyage. Therefore, the D* algorithm was used to address these problems. The starting point was near Busan New Port, and the destination was Ulsan Port. The navigable area was designated based on a combination of the ship trajectory data and grid in the target area. The initial path plan generated using the D* algorithm was analyzed with 33 waypoints and a total distance of 113.946 km. The final path plan was simplified using the Douglas-Peucker algorithm. It was analyzed with a total distance of 110.156 km and 10 waypoints. This is approximately 3.05% less than the total distance of the initial passage plan of the ship. This study demonstrated the feasibility of automatically generating a path plan in coastal navigation for maritime autonomous surface ships using the D* algorithm. Using the shortest distance-based path planning algorithm, the ship's fuel consumption and sailing time can be minimized.

Effect of Fusion Method and Passage Culture of Hanwoo (Korean Cattle) Ear Skin and Fetal Fibroblasts on the Development of Nuclear Transfer Embryos (한우의 귀세포와 태아섬유아세포의 융합 방법과 Passage 배양이 복제수정란의 발달에 미치는 영향)

  • Yang Byoung-Chul;Im Gi-Sun;Lee Sang-Ki;Kim Se-Woong;Kim Dong-Hoon;Seong Hwan-Hoo;Yang Boh-Suk
    • Reproductive and Developmental Biology
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    • v.30 no.1
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    • pp.53-58
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    • 2006
  • The study was conducted to evaluate the effects of culture period and fusion method on the development of somatic cell nuclear transfer (SCNT) embryos reconstituted with Korean bovine fetal fibroblast cells (KbFF) and Korean bovine adult ear skin fibroblast cells (KbESF). KbFF were isolated from a day 51 Korean cattle (Hanwoo) fetus, and KbESF were isolated from a 28 month old Hanwoo calf. The cells were cultured up to 15 weeks (passage 15) in vitro for SCNT. Chamber and electrode needles were used for comparing fusion of reconstituted eggs. The doubling times of KbFF and KbESF were 17.3 hr and 24.3 hr, respectively. The fusion and cleavage rates were significantly higher in needle group (76.1 and 81.2% respectively, P<0.05) than those in chamber group. However, the blastocyst development rate was not different between both groups. Fusion and cleavage rates of NT eggs reconstituted with KbESF did not affected by passage number, however, blastocyst rates were lower in passage $1{\sim}4$ group (21.3%) than passage $5{\sim}8$ (39.4%) and $13{\sim}15$ groups (40.4%, P<0.05). Whereas, fusion rate was lower in passage $1{\sim}4$ group (61.5%) than those of passage $5{\sim}8$(75.0%) and $13{\sim}15$ (76.8%) groups, but cleavage and blastocyst rates were similar regardless of passage number in the KbFF. The results suggest that fusion method can affect the development of SCNT embryos, whereas the long term culture up to 15 passages may not affect the development of SCNT embryos.

A Statistical Survey of the Foreign Bodies in the Food and Air Passages (식도및 기도이물의 통계적 고찰)

  • Lee, Min-Hyung;Kang, Baek;Lee, Byung-Hee;Cheon, Kyung-Doo;Kim, Chul-Woo
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1983.05a
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    • pp.6.3-6
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    • 1983
  • A total of 287 patients with foreign body in the air and food passage was treated in our unit between 1972 and 1982 and the following results were obtained : 1) The ratio between food and air passage was about 8 : 1. 2) The most common foreign bodies in the esophagus were coin (55.8%) and bone (28.5 %). Beans were the most common in the air passage (39.4%). 3) In sex distribution, there was no significant difference between male and females in the esophageal foreign bodies, but in the air passage male were prevalent (M : F = 57.9% : 42.1%). 4) In the age incidence, 61.8 % of the esophageal foreign bodies and 71 % of the foreign bodies in the air passage were under 5 Years of age. 5) The most prevalent site of Lodgement in the esophagus was the first narrowing (82.3 %). In the air passage, bronchial foreign bodies were more common and the right bronchus was the more frequent site (2 : 1). 6) In duration of lodgement, 62.2 % of esophageal foreign bodies and 55.2 % of foreign bodies in the air passage were removed within one day. 7) The most common complication of foreign bodies in the air passage was pneumonia (55.5%). 8) The removal of the foreign bodies in the air passage was performed by ventilation - bronchoscopy (84.3%). Two of 38 cases expired.

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Numerical Analysis on the Working Fluid Flow of Suction-passage for Reciprocating Compressor (왕복동식 수소압축기의 흡입통로내 작동유체 유동해석)

  • Lee, Gyeong-Hwan;Rahman, Mohammad Shiddiqur;Shim, Kyu-Jin;Jeong, Hyo-Min;Chung, Han-Shik
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.8
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    • pp.1201-1207
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    • 2008
  • Numerical analysis information will be very useful to improve fluid system. General information about an internal gas flow is presented by numerical analysis approach. Relating with hydrogen compressing system, which have an important role in hydrogen energy utilization, this should be a useful tool to observe the flow quickly and clearly. Flow characteristic analysis, including pressure and turbulence kinetic energy distribution of hydrogen gas coming to the cylinder of a reciprocating compressor are presented in this paper. Suction-passage model is designed based on real model of hydrogen compressor. Pressure boundary conditions are applied considering the real condition of operating system. The result shows pressure and turbulence kinetic energy are not distributed uniformly along the passage of the Hydrogen system. Path line or particles tracks help to demonstrate flow characteristics inside the passage. The existence of vortices and flow direction can be precisely predicted. Based on this result, the design improvement, such as reducing the varying flow parameters and flow reorientation should be done. Consequently, development of the better hydrogen compressing system will be achieved.

A Study on the Development of Ship's Passage Risk Assessment Simulator (선박항로 위험도 평가 시뮬레이터 개발에 관한 연구)

  • Kim, Kwang-Il;Jeong, Jung Sik;Park, Gyei-Kark
    • Journal of the Korean Institute of Intelligent Systems
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    • v.23 no.3
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    • pp.220-225
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    • 2013
  • Accidents between ships occur frequently at the traffic congestion area. Once a maritime accidents occur, it is likely to end up with critical damaged accidents. This paper develop a simulator for assessing quantitative risk based on statical maritime traffic data and realtime traffic distribution. Ship's passage risk assessment simulator consist of import of division of passage data, traffic distribution analysis and passage risk assessment analysis. Maritime traffic data of WANDO waterway apply to simulator for calculation of quantitative risk rate of waterway.

Ethnographies of Clothing in Incheon Province( I )- Focus on passage ritual clothes - (민속조사를 통해 본 인천지 역의 의생활( I ) - 통과의례복식 중심 -)

  • Chang In-Woo
    • Journal of the Korea Fashion and Costume Design Association
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    • v.7 no.2
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    • pp.51-60
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    • 2005
  • This ethnography is on the passage ritual clothes in Incheon province. This ethnography invatigates in two villages of people who has same family name -Family 'Cheung' (from Young-il) in Yeonsoo-dong and Family 'Lee'(from Cheun-joo) in dongyang-dong- in August to December 2003. The object of examination is 80's and 70's old women who have lived and had lived up to recent in two villages. (grand mother Sung, Cho, Cheung and yoon) The clothes of passage ritual are Baenaeoht is the first clothes of the newborn baby(swaddling), A wedding ceremony clothe is the clothing for the coming-of-age ceremony, Honryebouk is the clothing for wedding, Sangbouk in the clothing for mourning, shroud is the clothing for the dead, sacrificial robes. The result of ethnogrphy is the passage ritual clothes in Incheon Province similar with other Provinces in aspect of the name and the form and wearing of the clothes. there are remarkable differences in making method from making by oneself to purchase(swaddling$\cdot$shroud), westernize(clothes for wedding and mourning), simplification (sacrificial) between ritual for their parents and their husband and children.

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