• Journal of Soil and Groundwater Environment
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• v.10 no.6
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• pp.20-31
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• 2005

Three dimensional Monte-Carlo simulations of non-ergodic transport of a lion-reactive solute plume by steady-state groundwater flow under a uniform mean velocity in isotropic heterogeneous aquifers were conducted. The log-normally distributed hydraulic conductivity, K(x), is modeled as a random field. Significant efforts are made to reduce tile simulation uncertainties. Ensemble averages of the second spatial moments of the plume and plume centroid variances were simulated with 1600 Monte Carlo runs for three variances of log K, ${\sigma}_Y^2=0.09,\;0.23$, and 0.46, and three dimensionless lengths of line plume sources normal to the mean velocity. The simulated second spatial moment and the plume centroid variance in longitudinal direction fit well to the first order theoretical results while the simulated transverse moments are generally larger than the first order results. The first order theoretical results significantly underestimated the simulated dimensionless transverse moments for the aquifers of large ${\sigma}_Y^2$ and large dimensionless time. The ergodic condition for the second spatial moments is far from reaching in all cases simulated, and transport In transverse directions may reach ergodic condition much slower than that in longitudinal direction. The evolution of the contaminant transported in a heterogeneous aquifer is not affected by the shape of the initial plume but affected mainly by the degree of the heterogeneity and the size of the initial plume.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.7
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• pp.492-507
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• 2010

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. 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 piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps 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 the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.

• Economic and Environmental Geology
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• v.57 no.2
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• pp.161-175
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• 2024

Aggregate typically refers to sand and gravel formed by the transportation of rocks in rivers or artificially crushed, constituting a core resource in the construction industry. Gyeongsangbuk-do, the largest administrative area in South Korea, produces various sources of gravel, including forest, land (excluding other sources), river, and crushed stone. As of 2022, it has extracted approximately 6.96 million cubic meters of aggregate, with permitted production totaling around 4.07 million cubic meters and reported production of about 2.88 million cubic meters. The aggregate demand in Gyeongsangbuk-do is estimated to be 12.39 million cubic meters according to the estimation method in Ready-Mix Concrete. From the supply perspective, about 120 extraction sites are operational, with most municipalities maintaining an appropriate balance between aggregate demand and supply. However, in some areas, there is inbound and outbound transportation of aggregate to neighboring regions. Regions with significant inbound and outbound aggregate transportation in Gyeongsangbuk-do are areas connected to Daegu Metropolitan City and Pohang City along the Gyeongbu rail line, showing a high correlation with population distribution. Gyeongsangbuk-do faces challenges such as population decline, aging rural areas, and insufficient balanced regional development. Analysis using GIS reveals these trends in gravel demand and supply. Currently in this study, Gyeongsangbuk-do meets its demand for aggregate through the supply of various aggregate sources, maintaining stable aggregate procurement. River and terrestrial aggregates may be sustained as short-term supply strategies due to the difficulty of longterm development. Considering the reliance on raw material supply for selective crushing, it suggests the need for raw material management to maintain stability. Gyeongsangbuk-do highlights quarries in the forest as an important resource for sustainable aggregate supply, advocating for the development of large-scale aggregate quarries as a long-term alternative. These research findings are expected to provide valuable insights for formulating strategies for sustainable management and stable utilization of aggregate resources.

• Journal of the Daesoon Academy of Sciences
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• v.36
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• pp.1-34
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• 2020

It has been suggested that Jeungsan's prophetic poem that starts with the verse "For about seven or eight years, there will be a castle in the ancient country [七八年間古國城] ⋯" originally comes from Prophecies of Jeong Gam (鄭鑑錄). Despite Jeungsan, himself, obviously having been critical of that text, this claim has become the basic grounds for discourse suggesting that Jeungsan was not only interested in Prophecies of Jeong Gam but also considerably influenced by the text. However, the claim itself was formulated due to misunderstandings of the Chinese poems that had been included in A Compilation of Secret Prophecies Hidden in the Family-clan of Seogye (西溪家臧訣). These poems pursue a different ideological orientation than the poem from Prophecies of Jeong Gam. Ultimately, the Chinese poem in the verse 84 the chapter titled, Prophetic Elucidations in The Canonical Scripture of Daesoon Jinrihoe cannot provide a basis for the claim that Jeungsan was strongly influenced by Prophecies of Jeong Gam. This claim that Prophecies of Jeong Gam made a deep impact on Jeungsan and Daesoon Thought was based on three other texts outside of those that appear within verse 84 of Prophetic Elucidations. The first supposedly-related line is: "Heaven opens at the period of the Rat (Ja 子), Earth opens at the period of the Ox (Chuk 丑), humankind starts at the period of the Tiger (Ihn 寅)." This line comes from from Shao Kangjie's Book of Supreme World Ordering Principles (皇極經世), and the line could be quoted idiomatically as an expression in the Joseon Dynasty. Accordingly, attempts to relate Daesoon Thought to Prophecies of Jeong Gam are a distortion that arise from the assumption that Jeungsan had a significant interest in Prophecies of Jeong Gam. The second related line is "At the foot of Mount Mother (母岳山), a golden icon of Buddha has the ability to speak [母岳山下 金佛能言]." That line is nearly identical to the verse "On the summit of Mount Mother, a golden icon of Buddha has the ability to speak [母岳山頭 金佛能言]." Yet, Jeungsan changed '頭 (du, the summit)' to '下 (ha, the foot or under)' and express his own unique religious prophecy. This allusion to the prophecies of Jeong Gam is actually a criticism designed to disprove the earlier prophecy. Third, is the verse, "The form of Buddhism, creation of daoism, and propriety of Confucianism [佛之形體仙之造化儒之凡節]," which is characteristically related to Daesoon Thought. This verse can only be found in the prophetic text, Prophecies of Chochang (蕉蒼訣), and it is provided a main source when alleging that Prophecies of Jeong Gam was an influence on Daesoon Thought. However, considering the context of Prophecies of Chochang and the year of its publication (it is assumed to be compiled after 1950s), this does not hold water as Jeungsan had already passed into Heaven several decades before that time. This disqualifies the verse from being a basis for asserting Prophecies of Jeong Gam as an influence on Daesoon Thought. Contrary to the original assertion, there is a considerable amount of evidence that Prophecies of Chochang absorbed aspects of Daesoon Thought, which were simply revised in a novel way. There is no truly compelling evidence underpinning the argument that Prophecies of Jeong Gam had a unilateral impact on Daesoon Thought. There seems to be a great deal of confusion and numerous misinterpretations on this matter. Therefore, the claim that Daesoon Thought, as developed by Jeungsan, was influenced by the discourse on dynastic revolution and feng shui contained in Prophecies of Jeong Gam should be re-examined at the level of its very premise.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.848-857
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• 2018

Recently, around the world, active development of new renewable energy sources including solar power, waves, and fuel cells, etc. has taken place. Particularly, floating offshore wind farms have been developed for saving costs through large scale production, using high-quality wind power and minimizing noise damage in the ocean area. The development of floating wind farms requires an evaluation of the Maritime Safety Audit Scheme under the Maritime Safety Act in Korea. Floating wind farms shall be assessed by applying the line and area concept for systematic development, management and utilization of specified sea water. The development of appropriate evaluation methods and standards is also required. In this study, proper standards for marine traffic surveys and assessments were established and a systemic treatment was studied for assessing marine spatial area. First, a marine traffic data collector using AIS or radar was designed to conduct marine traffic surveys. In addition, assessment methods were proposed such as historical tracks, traffic density and marine traffic pattern analysis applying the line and area concept. Marine traffic density can be evaluated by spatial and temporal means, with an adjusted grid-cell scale. Marine traffic pattern analysis was proposed for assessing ship movement patterns for transit or work in sea areas. Finally, conceptual design of a Marine Traffic and Safety Assessment Solution (MaTSAS) was competed that can be analyzed automatically to collect and assess the marine traffic data. It could be possible to minimize inaccurate estimation due to human errors such as data omission or misprints through automated and systematic collection, analysis and retrieval of marine traffic data. This study could provides reliable assessment results, reflecting the line and area concept, according to sea area usage.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.1
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• pp.59-69
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• 2000

Environmental factors and phytoplankton community have been bimonthly investigated in order to clarify the bioecological characteristics of coral habitats around Moonsom at the southern Cheju Island from September 1995 to July 1996. Annual mean temperature and annual mean salinity were $17.4^{\circ}C$ and 34.06 psu, respectively, showing lower temperature-higher salinity in winter and higher temperature-lower salinity in summer, which means such conditions are inadequate for coral reef formation. Nutrient concentrations represent that total nitrogen ranged from $0.07{\sim}10.08\;{\mu}M$, phosphate from $0.05{\sim}1.70\;{\mu}M$, and silicate from $3.08{\sim}21.86\;{\mu}M$. The N/P ratio showed the range of 9.59-10.60 with decreasing offshore-ward, which means the phytoplankton community could be limited by nitrogen sources. Annual mean euphotic depth was 32.0m (18.9m-48.6m) with difference according to season and reveals the close relationship with the depth of coral distribution. Chlorophyll a concentrations of phytoplankton ranged from $0.12{\sim}1.51\;{\mu}g\;L^{-1}$ and standing crops from $1.5{\times}10^3{\sim}7.0{\times}10^5\;cells\;L^{-1}$, showing higher at inshore than at offshore with a blooming in May. A total of 128 species of phytoplankton occurred in all stations, representing 99 spp. of diatoms, 26 spp. of dinoflagellates, 2 spp. of silicoflagellates and 1 sp. of blue-green algae. Diatoms are main taxa in all seasons except for occupying by dinoflagellates in summer. Among dominant species, fParalia sulcata (Ehrenberg) Cleve and Cylindrotheca closterium (Ehrenberg) Lewin & Reimann were predominant and are likely to be main food sources for coral community. Annual mean species diversity index (H') was 1.84, showing lower than around the coast line of Cheju Island.

• The Korean Journal of Archival Studies
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• no.39
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• pp.281-318
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• 2014

This article aims to inquire into the decision making system and the sources of the original documents made by means of it in Imperial Japan, the colonial Chosun, GHQ, and the occupied Japan in terms of the post-war treatments of compensation on the Japanese colonial rules. It deals with them from 1910 to 1952 in the perspective of history and archivistics. This article attempts to establish the foundation on which the perception of the documents made in the Imperial Japan, its colony, and the occupied territory would be widened by placing the colonial rules and the compensation on them into a continuous line. The records of Japan's forced occupation of Korea during 1910-1945, and the original records documenting the decision making process of post-war compensation under GHQ, 1945-1952, have been dispersed in Korea, Japan and the United States. This dispersed preservation was mainly due to the complicated decision-making process among Governor-General of Chosun, the Japanese Imperial government, and the GHQ. It was the top-down styled, dual decision making system, in which the critical policies, personnel, and budget had been decided in Imperial homeland, while their implementations were made in the colonies. As a result, the records documenting the whole process of domination have been preserved dispersedly in Japan and its colonies. In particular, the accounts of not yet paid Korean workers that was forced to mobilize in Japan's colonial periods, which is emerging as the diplomatic conflict between Korea and Japan, had been dealt in the decrees of the Japanese government and policy-making of GHQ. It has already been changed to the problem as 'economic cooperation' from the 'debt'. Also, the critical records for post-war compensation were preserved dispersedly in the United States and Japan under the top-down decision making process of GHQ-Japan. Therefore, the dispersed records of 1910-1952 about the colonial rules by the Imperial Japan and the post-war compensation on them must be re-investigated for the adequate documentation in the context of time and space.

• Journal of the Korean Society for information Management
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• v.19 no.1
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• pp.23-46
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• 2002

With explosively increasing digital contents, library and Information center should have a new role between knowledge providers and knowledge users as information brokering organization. Electronic transaction system should be required for performing this brokering service since economic value is added to information and knowledge in information society. The developments and changes around library are keeping up with increasing building digital library and digitalizing printed sources. With the rapidly changing circumstances, the Internet is currently witnessing an explosive growth. By serving as a virtual information resource. the Internet can dramatically change the way business is conducted and Information is provided. However because of features o( the Internet like openness and information sharing, it has fundamental vulnerabilities in security issues. For Instance, disclosure of private information and line eavesdropping such as password, banking account, transaction data on network and so on are primary obstruction factors to activation of digital contents delivery on network. For high network security and authentication, this paper looks at smart card technologies and proposes multi-authentication protocol based on smart card on open network, implements and analyzes it.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.509-517
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• 2013

The purpose of this study is to assess the applicability of device-type stream coagulation process which combines physiochemical, biological processing for efficient improvement of water quality in small, middle-sized urban streams. The stream purification facility of this study is compose of pressure flotation type Micro Bubble Process(MBP) to remove TSS and TP and conduit line type Attached Microbial Pipe System(AMPS) to remove BOD. Test conditions of each device were set by floating stay time and change of ultra fine bubble injection amount of MBP, and change of AMPS stay time. Also, removal efficiency of pollution sources of each process were assess by change of season. As result of continuous operation of each process, MBP showed a maximum of TSS 83.69%, TP 95.15% process efficiency and AMPS showed a maximum of 52.95% TBOD5 removal efficiency. Also as result of circular operation of each process, MBP showed a maximum of TSS 69.75%, TP 70.17% process efficiency and AMPS showed a maximum of 68.58% TBOD5 removal efficiency. Therefore, it is considered that this stream coagulation process is effective in improving the water quality of streams in urban areas.

• Journal of Digital Convergence
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• v.16 no.9
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• pp.365-374
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• 2018

This study aims at understanding the components of on-line newspaper and how each newspaper's layout configuration is differentiated through the analysis on the websites of 10 general daily newspapers in the news stand of NAVER. The collection of data was implemented twice, and One-Way ANOVA was used as an analyzing way. The content of the analysis was carried out based on the types of visual images, the number of photo-based articles and title-based articles, the size of image for the main story, etc. As a result of analysis, the rate of news articles with the audios, videos, cards and slides differentiated from paper-based newspaper was low, and also the news articles using the informative graphics and the graphic sources were very small in number. As a whole, the newspapers in the news stand of NAVER showed that they attempt to make a distinction of their newspaper layout by using a variety of editorial techniques. The significance of this paper is to offer a basic clue to the editing formation to promote the news consumption of newspapers. Under the circumstance that the ecology of media is rapidly being reformed by new media technology, the continuous study of how the newspaper layout should be changed will be needed.