• Title/Summary/Keyword: district

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Corrosion Behavior of Boiler Tube under Circulation Water Conditions in District Heating System (지역난방 시스템의 순환수에 따른 보일러 튜브의 부식 특성)

  • Hong, Minki;Cho, Jeongmin;Song, Min Ji;Kim, Woo Cheol;Ha, Tae Baek;Lee, Soo Yeol
    • Corrosion Science and Technology
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    • v.17 no.6
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    • pp.287-291
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    • 2018
  • In this study, corrosion behavior of a SA178-A alloy used in the boiler tube of a district heating system was investigated in different environments where it was exposed to pure water, district heating (DH) water, and filtered district heating (FDH) water. After the corrosion test, the surface morphology was examined for observation of the number of pitting sites and pitting area fraction, using a scanning electron microscope. The DH water and FDH water conditions resulted in a lower corrosion potential and pitting potential, and revealed a significantly higher corrosion rate than the pure water condition. The pitting sites in the DH water (pH 9.6) were approximately eighteen times larger than those in the pure water (pH 9.6). Compared to the DH water, the corrosion potential became more noble in the FDH water condition, where iron ions were reduced through filtration. However, the corrosion rate increased in the FDH water due to an increased concentration of chloride ions, which deteriorated the stability of passive film.

A Study on Improvement Measures Related to District Unit Planning to Induce Landscape-Friendly Planning in Non-Urban Areas (비시가화지역의 경관친화적 계획 유도를 위한 지구단위계획 관련 제도 개선방안 연구)

  • Kim, Jin Hyo;Ra, Jung Hwa;Kwon, Oh Sung
    • Journal of Korean Society of Rural Planning
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    • v.27 no.2
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    • pp.1-11
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    • 2021
  • In this study, in order to induce landscape-friendly various development plans established at the district level, the contents of landscape plans appearing in domestic laws and systems and related previous studies are reviewed and comparative analysis is performed to advance the district-level landscape plan. The main focus was to explore the institutional methodology for this. The summary of the research results is as follows. First of all, as a result of analysis of the landscape plan content prescribed in the National Territory Planning Act and the enforcement decree of the same Act, the landscape plan content for natural elements and the landscape plan content for artifacts appeared mixed. Next, looking at the analysis results of the landscape plan contents in the Landscape Act, the Enforcement Decree of the same Act, and the landscape plan establishment guidelines, it is analyzed that the content mainly intended to improve the artificial landscape in terms of aesthetics, such as color, lighting, and buildings. Became. As a result of analysis of the landscape plan contents in the district unit plan establishment guidelines, it was found that the contents of the landscape plan for the skyline, night view, color, advertisements, and viewpoints were presented. As a result of the analysis of the landscape plan contents in the preceding study, the plan contents for ecological, recreational, and micro-visual aspects were revealed, and all three aspects aim to establish a landscape plan within the range of minimizing damage to nature. there was. Appeared to be. The results of this study are considered to be able to induce more landscape and nature-friendly district unit plans being conducted at the district level.

Study on Determination of Intention Type for Reasonable Conservation and Use on Baekdudaegan Protection Area (백두대간 보호구역의 권역별 지향성 설정에 관한 연구)

  • Kwak, Dooahn;Kim, Su-Jin
    • Journal of Korean Society of Forest Science
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    • v.111 no.1
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    • pp.72-80
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    • 2022
  • In this study, intention type was assigned to determine appropriate conservation and use of the Baekdudaegan Protection Area. To determine intention type, 84 indices were integrated into 7 types: the Natural Environment Protection District, Natural Scenic District, Agriculture and Forestry Promotion District, Living Environment Protection District, Education/Culture/Arts Promotion District, Recreation/Tourism Promotion District, and Disaster Management District. Intention types were decided by comparing the occupying proportion of the intention types for each watershed segment in which the Seoraksan, Taebaeksan, and Sockrisan region boundaries were included. Weight values were applied to each of the seven intention types because each type did not play an equal role in the target regions. Most regions were classified as Natural Environment Protection intention types because the Baekdudaegan area is regulated with strong forestry and environmental protection acts; thus, the weight values related to nature protection were higher than those for other types. To supplement the results from this study, additional research is needed to determine the intention type and weight for each region, and it will also be necessary to integrate sociocultural factors and field survey data.

A Study for Analysis of Micro Heat Grid Configuration and Deduction of Optimal Size in Hydrogen Cities (수소도시 내 마이크로 히트그리드 구성 방안 및 최적 규모 산정 연구)

  • JONGJUN LEE;SEUL-YE LIM;KYOUNG A SHIN;NAMWOONG KIM;DO HYEONG KIM;CHEOL GYU PARK
    • Transactions of the Korean hydrogen and new energy society
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    • v.33 no.6
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    • pp.845-855
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    • 2022
  • In response to climate change, the world is continuing efforts to reduce fossil fuels, expand renewable energy, and improve energy efficiency with the goal of achieving carbon neutrality. In particular, R&D is being made on the value chain covering the entire cycle of hydrogen production, storage, transportation, and utilization in order to shift the energy supply system to focus on hydrogen energy. Hydrogen-based energy sources can produce heat and electricity at the same time, so it is possible to utilize heat energy, which can increase overall efficiency. In this study, calculation of the optimal scale for hydrogen-based cogeneration and the composition of heat sources were reviewed. It refers to a method of the optimal heat source size according to the external heat supply and heat storage to be considered. The results of this study can be used as basic data for establishing a hydrogen-based energy supply model in the future.

Social division of labor in the traditional industry district - foursed on Damyang bamboo ware industry of Damyang and Yeoju pottery industry of Yeoju, South Korea (우리나라 재래공업 산지의 사회적 분업 - 담양죽제품과 여주 도자기 산지를 사례로 -)

  • ;;;Park, Yang-Choon;Lee, Chul-Woo;Park, Soon-Ho
    • Journal of the Korean Geographical Society
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    • v.30 no.3
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    • pp.269-295
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    • 1995
  • This research is concerned with the social division of labor within the traditional industry district: Damyang bamboo ware industry district and Yeoju pottery industry district in South Korea, Damyang bamboo ware and Yeoju pottery are well known of the Korean traditional industry. The social division of labor in an industry district is considered as an important factor. The social division of labor helps the traditional industry to survive today. This summary shows five significant points from the major findings. First, Damyang bamoo ware industry and Yoeju pottery industry have experienced the growth stages until 1945, the stagnation in the 1960s, and the business recovery in the 1980s. Most Korean traditional industries had been radically declined under the Japanese colonization; while, Damyang bamboo ware industry and Yeoju pottery industry district have been developed during above all stages. The extended market to Japan helped the local government to establish a training center, and to provide financial aids and technical aids to crafts men. During the 1960s and 1970s, mass production of substitute goods on factory system resulted in the decrease of demand of bamboo ware and pettery. During the 1980s, these industries have slowly recovered as a result of the increased income per capita. The high rate of economic growth in the 1960s and 1970s was playing an important role in the emerging the incleased demand of the bamboo ware and pottery. Second the production-and-marketing system in a traditional industry district became diversified to adjust the demand of products. In Damyang bamboo ware industry district, the level of social division of labor was low until the high economic development period. Bamboo ware were made by a farmer in a small domestic system, The bamboo goods were mainly sold in the periodic market of bamboo ware in Damyang. In the recession period in the 1960s and 1970s, the production-and-marketing system were diversified; a manufacturing-wholesale type business and small-factory type business became established; and the wholesale business and the export traders in the district appeared. In the recovery period in the 1980s, the production-and-marketing systems were more diversified; a small-factory type business started to depend On subcontractors for a part of process of production; and a wholesale business in the district engaged in production of bamboo ware. In Yeoju pottery industry district, the social division of labor was limited until the early 1970s. A pottery was made by a crafts man in a small-business of domestic system and sold by a middle man out of Yeoju. Since the late 1970s, production-and-marketing system become being diversified as a result of the increased demand in Japan and South Korea. In the 1970s, Korean traditional craft pottery was highiy demanded in Japan. The demand encouraged people in Yoeju to become craftsmen and/or to work in the pottery related occupation. In South Korea, the rapid economic growth resulted in incline to pottery due to the development of stainless and plastic bowls and dishes. The production facilities were modernized to provide pottery at the reasonable price. A small-busineas of domestic system was transformed into a small-factory type business. The social division of labor was intensified in the pottery production-and-maketing system. The manufacturing kaoline began to be seperated from the production process of pottery. Within the district, a pottery wholesale business and a retail business started to be established in the 1980s. Third the traditional industry district was divided into "completed one" and "not-completed one" according to whether or not the district firms led the function of the social division of labor. The Damyang bamboo ware industry district is "completed one": the firm within the district is in charge of the supply of raw material, the production and the marketing. In the Damyang bamboo ware district, the social division of labor w and reorganized labor system to improve the external economics effect through intensifying the social division of labor. Lastly, the social division of labor was playing an important role in the development of traditional industry districts. The subdivision of production process and the diversification of business reduced the production cost and overcame the labor shortage through hiring low-waged workers such as family members, the old people and housewives. An enterpriser with small amount of capital easily joined into the business. The risk from business recession were dispersed. The accumulated know-how in the production and maketing provided flexiblility to produce various goods and to extend the life-cycly of a product.d the life-cycly of a product.

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Pattern of Pusan Station Shopping District(II) (부산역(釜山驛) 상점가(商店街)의 패턴(II))

  • Kim, Won-Kyung
    • Journal of the Korean association of regional geographers
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    • v.5 no.2
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    • pp.47-117
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    • 1999
  • This study concern with the pattern of Pusan Station shopping district within Pusan City, Korea, one of the special functioned shopping district within Pusan City. This paper will serve as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(II) of this study deals with the functions including living related, restaurants and others. The pattern of floors, size of shops, street corners and widths of streets were also analysed. The results are as follows: 1. In terms of numbers of firms in living related function, Pusan Station shopping district is the $7{\sim}8th$ ranked central place among nine the highest centers within Pusan City. Pusan Station shopping district has not much promoted vertical spatial differentiation comparatively, and also it's intensity of land use is the lower among nine the highest centers. It is presented that intimate relationship between intensity of vertical land use and classes of central places within the city. The ratio of inns and hotels in Pusan Station shopping district is third ranked in Pusan City. And the size of inns and hotels in this area is the most largest among the nine highest ranked central places within Pusan City. These presented that the traditional characteristics of station area as a special functioned shopping district. Inns and hotels mainly located along the narrower and back street. And it forms agglomerated areas or 'an alley of inns' at the inner parts of blocks, some like a 'hidden flower'. In Korea, 'alley' means that an area of specialization gains the prestige, traditionally. 2. Restaurants mainly locate along the narrower and back streets. And agglomerated areas of restaurants coincide with the agglomerated area of drinking places. It shows that these two kinds of functions need the same locational conditions. The ratio of Chinese restaurants is the highest in the Pusan Station shopping district. It's due to the agglomerated area these kinds of restaurants at the 'China town'. 3. Pusan Station shopping district has been formed along the streets within the residential areas. It's means that this shopping district now at the initial or middle growth era in development stage of shopping areas. 4. In general, wholesales and light manufacturing are located at peripheries within shopping district. But in Pusan Station shopping district, it dose not appear these spatial pattern. It shows that this area is lower ranked central place and not much progressed in spatial differentiation. 5. Particular firms which customers and workers have stayed more longer period of time are located at the far from the first floor. This vertical spatial differentiation is similar to the horizontal sequences. 6. Firms which have more ability of rental payment are located at street comers such as banks and pharmacies. In Pusan Station shopping district commercial facilities could not invade into the second third floors at narrower streets and first floor of back streets, still now.

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KDHA NEWS

  • Korea District Heating Association
    • Intergrated Energy Industry
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    • s.2
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    • pp.80-83
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    • 2005
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