• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.171-176
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• 2000

A wastewater treatment pond system was developed for treatment and recycling of dairy cattle excreta of $5\;m^1$ per day. The wastes were diluted by the water used for clearing stalls. The system was composed of three ponds in series. A submerged gas collector for the recovery of methane was installed at the bottom of secondary pond with water depth of 2.4m. This paper deals mainly with performance of methane fermentation of secondary pond which is faclutative one. The average $BOD_5$, SS, TN, and TP concentrations of influent into secondary pond were 49.1, 53.4, 48.6, and 5.3 mg/l, and those of effluent from it were 27.9, 45.7, 30.8, 3.2 mg/l respectively. Methane fermentation of 2.4-meter-deep secondary pond bottom was well established at $16^{\circ}C$ and gas garnered from the collector at that temperature was 80% methane. Literature on methane fermentation of wastewater treatment ponds shows that methane bacteria grow well around $24^{\circ}C$, the rate of daily accumulation and decomposition of sludge is approximately equal at $19^{\circ}C$, and activities of methanogenic bacteria are ceased below $14^{\circ}C$. The good methane fermentation of the pond bottom around $16^{\circ}C$, about $3^{\circ}C$ lower than $19^{\circ}C$, results from temperature stability, anaerobic condition, and neutral pH of the bottom sludge layer. It is recommended that the depth of pond water could be 2.4m. Gas from the collector during active methane fermentation was almost 83% methane, less than 17% nitrogen. Carbon dioxide was less than 1% of the gas, which indicates that carbon dioxide produced in bottom sludges was dissolved in the overlaying water column. Thus a purified methane can be collected and used as energy source. Sludge accumulation on the pond bottom for a nine month period was 1.3cm and annual sludge depth can be estimated to be 1.7cm. Design of additional pond depth of 0.3m can lead to 15 - 20 year sludge removal.

• Management & Information Systems Review
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• v.39 no.1
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• pp.93-114
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• 2020

Platform is considered as an alternative strategy to the traditional linear pipeline based business. Moreover, in the 4th industrial revolution period, efficiency driven pipeline business model needs to be changed to platform business. We have such success stories about platform as Apple, Google, Amazon, Uber, and so on. However, for those smaller corporations, it is not easy to find out the transformation strategy. The essence of platform business is to leverage network effect in management. Thus platform based management can be rephrased as network management across the business functions. Research on platform business is popular and related to diverse facets. But few scholars cover what the research trend of the domain is. The main purpose of this paper is to identify the research trend on platform business in Korea. To do that we first propose the analytical model for platform architecture whose components are consumers, suppliers, artifacts, and IT platform system. We conjecture that mapping of the research work on platform to the components of the model will make us understand the hidden domain of platform research. We propose three hypotheses regarding the characteristics of research and one proposition for the transitional path from pipeline to platform business model. The mapping is based on the research articles filtered from the Korea Citation Index, using keyword search. Research papers are searched through the keywords provided by authors using the word of "platform". The filtered articles are summarized in terms of the attributes such as major component of platform considered, platform type, main purpose of the research, and research method. Using the filtered data, we test the hypotheses in exploratory ways. The contribution of our research is as follows: First, based on the findings, scholars can find the areas of research on the domain: areas where research has been matured and territory where future research is actively sought. Second, the proposition provided can give business practitioners the guideline for changing their strategy from pipeline to platform oriented. This research needs to be considered as exploratory not inferential since subjective judgments are involved in data collection, classification, and interpretation of research articles.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.36-59
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• 2021

This study infers the origin and production period of the , which is in the Onyang folk museum, through analysis and interpretation of the Haeju Palgyeong and exploration of the landscapes and traditions contained in the painting. The first collection of landscapes to Haeju was identified as Haeju Palgyeong by Ku Sa-meng (1531-1604). Yoo Man-ju, writing in 1782, referred to it as Go-palgyeong in 『Heumyeong』 while Haeju Palgyeong was defined as Geum-palgyeong (今八景), which is the Haeju Palgyeong in the earliest period confirmed by literature. is 'Boating on the Nam river (南江泛舟)', 'Lotus viewing at Buyongdang (芙蓉賞蓮)', 'Foot washing at Gwangseokcheon (廣石濯足)', 'Seokbyul at Haeunkyo (泣川送客)', 'Fishing at Haeunjeong (東亭釣魚)' and 'Sea view at Namsan( 南山望海)', and the final two contain a picture that contains 'Viewing the moon at Yeonghaeru (瀛海玩月)' and 'Writing contest and Archery at Baeklimjeong (栢林觀德)' The Suyang Chaemi(首陽採薇), Shingwang-jeoljeol (神光霽雪), and Jiseong falls (池城瀑布) of Gopalgyeong, which were excluded from Haeju Palgyeong, are all landscapes unfolding as a grand site of Suyangsan Mountain. is a result of the reorganization of Seunggyeong centered on Eupchi (邑治), away from the Suyangsan area. It has emerged as a seunggyeong of Haeju. The elaborateness of trying to contain the detailed prizes representing Haeju, such as the specialty sake of Haeju, is revealed. Most of the landscapes depicted in are historic and outstanding spots in Haemok, but the scenes of life related to daily life are properly arranged. In addition, Foot washing (濯足), Fishing(釣魚), Doing laundry (漂母), Lotus viewing (賞蓮), Sending guests (送客), Drinking (飮酒), sea viewing (望海), Moon viewing (玩月), Archery (射藝), Poetry (詩作), Drinking tea (飮茶), and Dancing (歌舞) are of various styles. Compared with the Gopalgyeongs, Haeju Palgyeong did not take into account the distribution of landscapes in the four seasons, and the small-sized view was also broken. When considering the time of the construction of Haeunjeong and the deterioration of Yeonghhoeru, it is believed that was produced in the early- to mid-18th century. is considered to be a painting that contributed to strengthening the sense of intimacy with the local people and promoting the pride of Haeju by showing the representative scenery of Haeju, such as scenic spots and customs, away from the ideal utopia.

• Korean Journal of Heritage: History & Science
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• v.57 no.3
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• pp.140-160
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• 2024

The implementation of the "Basic Law on Korean Heritage" on May 17, 2024, brought about significant changes in the operation of Korean heritage-related ordinances in 17 local governments. This study specifically analyzes the production, collection, and information transfer of Korean heritage information between the Korean Heritage Service and local governments, focusing on the provisions of the law. Finally, in order to achieve the goal of revitalizing the management of Korean heritage information, the study suggests five directions for improvement of the local government ordinance from three perspectives. Firstly, in order to systematize the production of Korean heritage information, it is necessary to specify the entities that produce and manage information in Korean heritage, and to select important Korean heritage information from the information produced and manage it strategically. In today's complex Korean heritage management environment, it is impossible to manage all the Korean heritage information produced by various stakeholders. Secondly, in order to systematize the delivery of Korean heritage information, detailed procedures related to the information to be delivered to the Korean Heritage Service should be specified, and a clear plan for information delivery and management between local and basic local governments should be defined. In the Korean heritage information delivery system, local governments play various roles as direct information providers, managers, consumers, and transmitters. Therefore, it is necessary to specify the provisions of the ordinance so that local governments can systematically fulfill their various roles in the Korean heritage information delivery system. Thirdly, in order to activate the production of Korean heritage information, local governments should review the provisions of the Act to ensure that important Korean heritage information generated from directory provisions and non-mandatory provisions, in addition to the mandatory provisions of the Korean Heritage Act, is not omitted. In particular, Korean heritage information is not just administrative information, but also includes specialized information for the maintenance of the current state of Korean heritage. Therefore, if certain Korean heritage information is partially missing, there may be a gap in intergovernmental communication for Korean heritage management.