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A Study on the Establishment Case of Technical Standard for Electronic Record Information Package (전자문서 정보패키지 구축 사례 연구 - '공인전자문서보관소 전자문서 정보패키지 기술규격 개발 연구'를 중심으로-)

  • Kim, Sung-Kyum
    • The Korean Journal of Archival Studies
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    • no.16
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    • pp.97-146
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    • 2007
  • Those days when people used paper to make up and manage all kinds of documents in the process of their jobs are gone now. Today electronic types of documents have replaced paper. Unlike paper documents, electronic ones contribute to the maximum job efficiency with their convenience in production and storage. But they too have some disadvantages; it's difficult to distinguish originals and copies like paper documents; it's not easy to examine if there is a change or damage to the documents; they are also prone to alteration and damage by the external influences in the electronic environment; and electronic documents require enormous amounts of workforce and costs for immediate measures to be taken according to the changes to the S/W and H/W environment. Despite all those weaknesses, however, electronic documents increasingly account for more percentage in the current job environment thanks to their job convenience and efficiency of production costs. Both the government and private sector have made efforts to come up with plans to maximize their advantages and minimize their risks at the same time. One of the methods is the Authorized Retention Center which is described in the study. There are a couple of prerequisites for its smooth operation; they should guarantee the legal validity of electronic documents in the administrative aspects and first secure the reliability and authenticity of electronic documents in the technological aspects. Responding to those needs, the Ministry of Commerce, Industry and Energy and the Korea Institute for Electronic Commerce, which were the two main bodies to drive the Authorized Retention Center project, revised the Electronic Commerce Act and supplemented the provisions to guarantee the legal validity of electronic documents in 2005 and conducted researches on the ways to preserve electronic documents for a long term and secure their reliability, which had been demanded by the users of the center, in 2006. In an attempt to fulfill those goals of the Authorized Retention Center, this study researched technical standard for electronic record information package of the center and applied the ISO 14721 information package model that's the standard for the long-term preservation of digital data. It also suggested a process to produce and manage information package so that there would be the SIP, AIP and DIP metadata features for the production, preservation, and utilization by users points of electronic documents and they could be implemented according to the center's policies. Based on the previous study, the study introduced the flow charts among the production and progress process, application methods and packages of technical standard for electronic record information package at the center and suggested some issues that should be consistently researched in the field of records management based on the results.

Particulate Matter and CO2 Improvement Effects by Vegetation-based Bio-filters and the Indoor Comfort Index Analysis (식생기반 바이오필터의 미세먼지, 이산화탄소 개선효과와 실내쾌적지수 분석)

  • Kim, Tae-Han;Choi, Boo-Hun;Choi, Na-Hyun;Jang, Eun-Suk
    • Korean Journal of Environmental Agriculture
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    • v.37 no.4
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    • pp.268-276
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    • 2018
  • BACKGROUND: In the month of January 2018, fine dust alerts and warnings were issued 36 times for $PM_{10}$ and 81 times for PM2.5. Air quality is becoming a serious issue nation-wide. Although interest in air-purifying plants is growing due to the controversy over the risk of chemical substances of regular air-purifying solutions, industrial spread of the plants has been limited due to their efficiency in air-conditioning perspective. METHODS AND RESULTS: This study aims to propose a vegetation-based bio-filter system that can assure total indoor air volume for the efficient application of air-purifying plants. In order to evaluate the quantitative performance of the system, time-series analysis was conducted on air-conditioning performance, indoor air quality, and comfort index improvement effects in a lecture room-style laboratory with 16 persons present in the room. The system provided 4.24 ACH ventilation rate and reduced indoor temperature by $1.6^{\circ}C$ and black bulb temperature by $1.0^{\circ}C$. Relative humidity increased by 24.4% and deteriorated comfort index. However, this seemed to be offset by turbulent flow created from the operation of air blowers. While $PM_{10}$ was reduced by 39.5% to $22.11{\mu}g/m^3$, $CO_2$ increased up to 1,329ppm. It is interpreted that released $CO_2$ could not be processed because light compensation point was not reached. As for the indoor comfort index, PMV was reduced by 83.6 % and PPD was reduced by 47.0% on average, indicating that indoor space in a comfort range could be created by operating vegetation-based bio-filters. CONCLUSION: The study confirmed that the vegetation-based bio-filter system is effective in lowering indoor temperature and $PM_{10}$ and has positive effects on creating comfortable indoor space in terms of PMV and PPD.

A study on the Cooking Vessel of Baekje Hanseong Period (백제 한성기 취사용기에 대한 검토 - 심발형토기와 장란형토기를 중심으로 -)

  • Jung, Su Ock
    • Korean Journal of Heritage: History & Science
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    • v.44 no.4
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    • pp.112-129
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    • 2011
  • This paper was written to understand, through the types and production techniques, how cooking vessels of Baekje Hanseong period had evolved, - the cooking vessels that were excavated from the historic sites of Baekje Hanseong Period such as Mongchontoseong and Pungnaptoseong of Seoul, the ancient tomb group of Seokchon-dong, and Misari historic site of Hanam. First, the results produced through the analysis of types of these cooking vessels are as followings: as for deep bowls, the maximum body diameter is found on the top of pottery, while as for an egg-shaped pottery, the maximum body diameter is found on the middle height of pottery. However, as for the rim diameter ratio to the neck diameter ratio of pottery, the said two typed potteries were shown to have smaller ones. In consideration of each historic site, as for deep bowls, the ancient tomb group of Seokchon-dong had potteries that had less volumes, were deeper, and had higher maximum body diameters. When it comes to an egg-shaped pottery, Pungnaptoseong had the potteries that were deeper than those of Misari historic site, and their potteries also had the maximum body diameter found on the middle height of pottery, and larger rim diameter ratio to the neck diameter of the pottery. The results produced though the analysis of the production techniques of these cooking vessels are as followings: in the case of deep bowls, as the width of a volume category gets larger, the pottery stamping with an anvil including patterns was more frequently used for pottery production. In this case, simultaneously braid patterns were frequently found on the outer sides of these potteries. In addition, it was found the basal walls of these potteries were thinnest in all typed potteries. This shows there occurred technique transitions according to the time flow. When it comes to an egg-shaped pottery as well, the pottery produced by using an anvil had the thinnest basal wall and its rim diameter ratio to its neck diameter ratio was smaller. Also around the mouth of this pottery, traces were found on its front, the traces formed by the strong rotating power. It is determined these two typed potteries were all produced by using an anvil to have thinner walls. Then, how these potteries were used? In the case of deep bowls, liquid food was put on a hearth or ground to be cooked whereas in the case of an egg-shaped pottery, the pottery was put on a puttumak(kitchen stove) mainly for boiling water. The deep bowls and egg-shaped potteries excavated from the center areas of Baekje Hanseong Period were not clearly determined about when their pastes or firing times were, but as for their production techniques, it was possible to check how they had developed. Moreover, it was determined that in the changing aspects of their production techniques, temporalite is also reflected.

Development and evaluation of a 2-dimensional land surface flood analysis model using uniform square grid (정형 사각 격자 기반의 2차원 지표면 침수해석 모형 개발 및 평가)

  • Choi, Yun-Seok;Kim, Joo-Hun;Choi, Cheon-Kyu;Kim, Kyung-Tak
    • Journal of Korea Water Resources Association
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    • v.52 no.5
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    • pp.361-372
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    • 2019
  • The purpose of this study is to develop a two-dimensional land surface flood analysis model based on uniform square grid using the governing equations except for the convective acceleration term in the momentum equation. Finite volume method and implicit method were applied to spatial and temporal discretization. In order to reduce the execution time of the model, parallel computation techniques using CPU were applied. To verify the developed model, the model was compared with the analytical solution and the behavior of the model was evaluated through numerical experiments in the virtual domain. In addition, inundation analyzes were performed at different spatial resolutions for the domestic Janghowon area and the Sebou river area in Morocco, and the results were compared with the analysis results using the CAESER-LISFLOOD (CLF) model. In model verification, simulation results were well matched with the analytical solution, and the flow analyses in the virtual domain were also evaluated to be reasonable. The results of inundation simulations in the Janghowon and the Sebou river area by this study and CLF model were similar with each other and for Janghowon area, the simulation result was also similar to the flooding area of flood hazard map. The different parts in the simulation results of this study and the CLF model were compared and evaluated for each case. The results of this study suggest that the model proposed in this study can simulate the flooding well in the floodplain. However, in case of flood analysis using the model presented in this study, the characteristics and limitations of the model by domain composition method, governing equation and numerical method should be fully considered.

Understanding the Access and Benefit-Sharing of Genetic Resources for Environmental Ecology Researchers (나고야의정서 이행에 따른 ABS 체계의 이해와 환경생태분야 연구자의 대응방안)

  • Lee, Jonghyun;An, Minho;Chang, YounHyo
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.336-346
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    • 2021
  • The enforcement of the Nagoya Protocol, which regulates the acquisition and use of genetic sources, an essential material for biotechnology R&D, has imposed a burden for additional documentation works to researchers. In the past, countries regarded genetic resources as a common human heritage and thus allowed researchers to use them freely. However, they can no longer afford the luxury of such freedom now since many countries are introducing new laws and regulations on the acquisition and use of the resources as the Nagoya Protocol recognizes the exclusive ownership of genetic resources. Therefore, Korea, which is highly dependent on foreign genetic resources, needs a more systematic response. This paper aims to review the key contents of the Nagoya Protocol to raise awareness among domestic and foreign genetic resource users, including researchers of environment and ecology and present the overall structure, and flow of acquisition, access, and benefit sharing (ABS) for the use of foreign genetic resources to help them respond appropriately to the new landscape. The researchers' efforts and support at the national level are necessary at the same time to appropriately respond to the Nagoya Protocol. First, the researchers must understand the overall framework and the specific response in each stage under the Nagoya Protocol scheme. It is necessary to respond to the ABS procedure of the resource provider country from accessing genetic resources to sharing benefits resulting from it. In that regard, the Nagoya Protocol has imposed more restrictions on research activities and raised the burden outside of research. The current trend of recognizing the country's sovereign rights over genetic resources is likely to continue and widespread worldwide as resource-rich countries are expected to continue protecting their resources. Therefore, our study will help environmental ecology researchers understand ABS and conduct research under the Nagoya Protocol and legal obligations of resource provider countries step by step, from access to benefit sharing.

A Review of Ecological Niche Theory from the Early 1900s to the Present (생태적 지위(Ecological Niche) 이론에 대한 검토 및 제언)

  • Koo, Kyung Ah;Park, Seon-Uk
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.316-335
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    • 2021
  • This study reviewed the change of theory of ecological niche(concepts and definitions) over time to provide a theoretical basis for habitat-related studies of animals and plants. Accordingly, it analyzed and summarized the major discussion trends of ecological niche worldwide in each period from the 1900s to the present. Countries advanced in ecological studies, such as the EU and the USA, have conducted theoretical and empirical studies on the ecological niche since the early 1990s. The concept of the ecological niche was introduced in the early 1900s, developed in the mid-1900s, and advanced from the mid-1900s to the late 1900s. Since the 2000s, the advanced concept has diversified with new developments in technologies and research methods. The factors suggested by theoretical and empirical studies in defining the ecological niche of a species include 1) population dynamics of the target species, 2) all biotic conditions to sustain a population (food relationship and material flow in the food chain), 3) all non-biotic conditions to sustain a population (physical environmental conditions), 4) all direct and indirect interactions between these environmental factors, and 5) response and adaptation mechanisms that include the migratory ability of the target species or genetic diversity and adaptability to change. Unlike such international advancement, there have not been sufficient theoretical, philosophical, and empirical studies of ecological niche in Korea. The concepts and definitions by Greennell, Elton, and Hutchinson were selectively and partially borrowed for empirical studies without full description. Considering that the theory of ecological niche becomes the foundation for habitat-based species conservation and restoration, it is necessary to seek diversification and advancement of theoretical and empirical research and research methods and technological development. It will provide an important foundation for the academic advancement of ecology and for establishing and implementing policies to preserve and restore ecology and biodiversity effectively and successfully in Korea.

Field Assessment of in Situ Remediation of NO3--contaminated Ground Water Using Zero-valent Iron/Bio Composite Media (영가철/바이오 복합처리제를 이용한 질산성 질소 오염 지하수의 현장 지중정화 적용성 평가)

  • Joo, Wan-Ho;Chang, Yoon-Young
    • Journal of Environmental Impact Assessment
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    • v.30 no.1
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    • pp.35-48
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    • 2021
  • In this study, the assessment of field applicability of in-situ remediation of nitrate-contaminated groundwater located in Yesan-gun was performed. Zero-valent iron/bio composite media injected PRB (Permeable Reactive Barrier) and monitoring well were installed in the contaminated groundwater site and monitored main remediation indicators during the PRB operation. Nitrate, nitrite, ammonia, Fe ion, TOC, and turbidity were analyzed and the diversity and population of microorganism in the PRB installed site were investigated for the verification of effect of injected PRB. In the study site where is an agricultural area, a river flows from west to east that forms a river boundary and the southern area has an impermeable sector. It was found that nitrate flows into the river, which is similar as groundwater flow. Simulation result for the fate of nitrate in groundwater showed steady state of nitrate arrived after 3~5 years passed. However, it is just to consider current conditions with no additional input of contaminant source, if additional input of contaminant source occurs contamination dispersion and time for steady state are expected to be increased. The monitoring results showed that Fe ion, TOC and turbidity in groundwater were not clearly changed in concentration after PRB installation, which indicates adaptability of the injected PRB for remediation of groundwater with no additional harmful effect to water quality. The concentration of nitrate maintained less than 5mg/L until 42 days after PRB installation and recovered its initial concentration after 84 days passed and showed termination of reactivity of injected zero-valent iron/bio composite media for removal nitrate. Nitrite and ammonia ions found after installation of PRB indicates reductive removal of nitrate. And the outstanding increase of microorganism diversity and population of Betaproteobacteria Class which includes denitrification microorganism explains biologically reductive removal of nitrate in injected PRB.

An Experimental Study on the Hydration Heat of Concrete Using Phosphate based Inorganic Salt (인산계 무기염을 이용한 콘크리트의 수화 발열 특성에 관한 실험적 연구)

  • Jeong, Seok-Man;Kim, Se-Hwan;Yang, Wan-Hee;Kim, Young-Sun;Ki, Jun-Do;Lee, Gun-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.20 no.6
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    • pp.489-495
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    • 2020
  • Whereas the control of the hydration heat in mass concrete has been important as the concrete structures enlarge, many conventional strategies show some limitations in their effectiveness and practicality. Therefore, In this study, as a solution of controling the heat of hydration of mass concrete, a method to reduce the heat of hydration by controlling the hardening of cement was examined. The reduction of the hydration heat by the developed Phosphate Inorganic Salt was basically verified in the insulated boxes filled with binder paste or concrete mixture. That is, the effects of the Phosphate Inorganic Salt on the hydration heat, flow or slump, and compressive strength were analyzed in binary and ternary blended cement which is generally used for low heat. As a result, the internal maximum temperature rise induced by the hydration heat was decreased by 9.5~10.6% and 10.1~11.7% for binder paste and concrete mixed with the Phosphate Inorganic Salt, respectively. Besides, the delay of the time corresponding to the peak temperature was apparently observed, which is beneficial to the emission of the internal hydration heat in real structures. The Phosphate Inorganic Salt that was developed and verified by a series of the aforementioned experiments showed better performance than the existing ones in terms of the control of the hydration heat and other performance. It can be used for the purpose of hydration heat of mass concrete in the future.

A Study of Fluoride and Arsenic Adsorption from Aqueous Solution Using Alum Sludge Based Adsorbent (알럼 슬러지 기반 흡착제를 이용한 수용액상 불소 및 비소 흡착에 관한 연구)

  • Lee, Joon Hak;Ji, Won Hyun;Lee, Jin Soo;Park, Seong Sook;Choi, Kung Won;Kang, Chan Ung;Kim, Sun Joon
    • Economic and Environmental Geology
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    • v.53 no.6
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    • pp.667-675
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    • 2020
  • An Alum-sludge based adsorbent (ASBA) was synthesized by the hydrothermal treatment of alum sludge obtained from settling basin in water treatment plant. ASBA was applied to remove fluoride and arsenic in artificially-contaminated aqueous solutions and mine drainage. The mineralogical crystal structure, composition, and specific surface area of ASBA were identified. The result revealed that ASBA has irregular pores and a specific surface area of 87.25 ㎡ g-1 on its surface, which is advantageous for quick and facile adsorption. The main mineral components of the adsorbent were found to be quartz(SiO2), montmorillonite((Al,Mg)2Si4O10(OH)2·4H2O) and albite(NaAlSi3O8). The effects of pH, reaction time, initial concentration, and temperature on removal of fluoride and arsenic were examined. The results of the experiments showed that, the adsorbed amount of fluoride and arsenic gradually decreased with increasing pH. Based on the results of kinetic and isotherm experiments, the maximum adsorption capacity of fluoride and arsenic were 7.6 and 5.6 mg g-1, respectively. Developed models of fluoride and arsenic were suitable for the Langmuir and Freundlich models. Moreover, As for fluoride and arsenic, the increase rate of adsorption concentration decreased after 8 and 12 hr, respectively, after the start of the reaction. Also, the thermodynamic data showed that the amount of fluoride and arsenic adsorbed onto ASBA increased with increasing temperature from 25℃ to 35℃, indicating that the adsorption was endothermic and non-spontaneous reaction. As a result of regeneration experiments, ASBA can be regenerated by 1N of NaOH. In the actual mine drainage experiment, it was found that it has relatively high removal rates of 77% and 69%. The experimental results show ASBA is effective as an adsorbent for removal fluoride and arsenic from mine drainage, which has a small flow rate and acid/neutral pH environment.

The Theory of Chen tuan's Internal Alchemy and Intermixture of Taoism, Buddhism and Neo-Confucianism (진단의 내단이론과 삼교회통론)

  • Kim, Kyeong-Soo
    • The Journal of Korean Philosophical History
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    • no.31
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    • pp.53-86
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    • 2011
  • Taoism exercised its influence and has made much progress apparently under the aegis of the Tang dynasty. But since the external alchemy, a traditional way of eternal life that they have pursued, met the limitation, they were placed in a situation where they needed to seek a new discipline. From this period to the early North Song dynasty, three religions have established the unique theoretical systems of their own theory of ascetic practices. They showed their own unique formats as follows. Neo-Confucianism established the theory of moral training, Buddhism did the theory of ascetic practices and Taoism had theory of discipline. By this time, a person who claimed the Intermixture of Three Religions composed the new system of theory of ascetic practice by taking advantage of other religions and putting them into his own view. Chen tuan established the theory of internal alchemy of Taoism and was the most influential figure in the world of thought since North Song dynasty. He clearly declared that he accepted the merits of other religions in his theory. He added I Ching of Confucianism in I Ching of secret of Taoism to stop the logical gaps during the process of disciplines in Taoism and took ascetic practices on mind of Buddhism into his system while he sought a way to integrate the dual structure of body and mind. The theory of Chen tuan's internal alchemy was training schema with stages of 'YeonJeongHwaGi', 'YeonGiHwaSin', and 'YeonSinHwanHeo' based on the concepts of vital, energy and spirit. The internal alchemy practice that Chen tuan was saying started from the practice of Zen to keep the mind calm with the basis of fundamental principles of interpretation of book of change according to Taoism. When a person reached the state to be in concert with all changes at the end of the silence and be full of wisdoms, he finally returned to the state of BokGwiMuGeuk by taking the flow of subtle mind and transforming it into energy. He expressed this process by drawing 'MuGeukDo'. Oriental philosophy categorized human into 'phenomenal existence' and 'original existence'. The logic of theory of ascetic practice has been established from these 'category of existence'. It would be determined whether it will return to 'original existence' or be stepped up from 'phenomenal existence' according to how the concept of 'self' or 'I' was made. Chen tuan who established the theory of internal alchemy in Taoism has established the unique theory of internal alchemy discipline and system of intermixture of three religions in this aspect. Today is called 'era of self-loss' or 'era of incurable diseases' caused by environmental pollution. It's still meaningful to review the theory of discipline of Chen tuan's connecting the body and the soul to heal the self, and keep life healthy and pursue the new way of discipline based on it.