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Application of Liriope platyphylla, Ornamental Korean Native Plants, for Contaminated Soils in Urban Areas (도시 내 중금속 오염지의 관상식물로서 자생 맥문동(Liriope platyphylla)의 적용성 평가)

  • Ju, Jin-Hee;Yoon, Yong-Han
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.5
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    • pp.81-87
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    • 2014
  • Heavy metal pollution is a widespread global problem causing serious environmental concern. Heavy metals such as Cd, Pb, and Zn can induce toxicity in all organisms if the soil levels of contaminants reach critical values. The aim of the present study was to examine the application of Liriope platyphylla, an ornamental Korean native plant with great potential for contaminated soil in urban areas, to determine tolerance for Cd, Pb, and Zn. Plants were grown in amended artificial soil with Cd, Pb, and Zn at 0, 100, 250, and $500mg{\cdot}kg^{-1}$ for 7 months. The length of leaf, width of leaf, total leaf number, dead leaf number, new leaf number, chlorophyll contents, and ornamental value were monitored from May to August, during growth the period. The relative leaf length and leaf width displayed rapidly decreasing tendencies with an increasing Cd concentration beginning from 4 months after planting. The same decreasing tendency was observed in total leaf number, new leaf number, chlorophyll contents, and ornamental values showed a trend of Control> $Cd_{100}$ > $Cd_{250}$ > $Cd_{500}$. In Pb concentration treatments, the relative leaf length and leaf width were significantly lower in plants grown at $250mg{\cdot}kg^{-1}$ and $500mg{\cdot}kg^{-1}$ as compared to the Control, $100mg{\cdot}kg^{-1}$. The total leaf number, new leaf number, and dead leaf number did not show significant difference among treatments in Control and $Pb_{100}$ but chlorophyll contents and ornamental value decreased with increasing Pb supply concentration treatments. However, in Zn supply treatments, the relative leaf length was higher at $100mg{\cdot}kg^{-1}$ than the Control, $250mg{\cdot}kg^{-1}$, $500mg{\cdot}kg^{-1}$, but the relative leaf width decreased compared to the Control, $Zn_{100}$, $Zn_{250}$, and $Zn_{500}$. The total leaf number, dead leaf number, new leaf number, and ornamental value showed the lowest value in plants grown in $Zn_{500}$ treatment but no significant differences were found among other treatments.

HACCP Application of Instant Ablactation Baby Food Processing (즉석 이유식 제조시 HACCP의 적용)

  • 이정규;노완섭
    • The Korean Journal of Food And Nutrition
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    • v.14 no.5
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    • pp.457-466
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    • 2001
  • In this study. HACCP system was applied to improve the quality of instant ablactation baby food with rising sanitary problem among SunSig(powder of roasted grains and vegetables) . It took about 9min 30 second to produce and the temperature status of raw materials were 30.9∼31.8$\^{C}$. Raw material and production phase goods had average 6.2 in pH and 0.23∼0.63 in water activity. The average number of total aerobic bacteria(TAB) and coliform were 1.4$\times$10$^4$ CFU/g, 5.5$\times$10 CFU/g in raw materials. And the number became 8.7$\times$10$^2$ CFU/g, 6.9$\times$10 CFU/g after 1st grinding step. The distributions of TAB and coliform in equipments were 3.8$\times$10$^4$ CFU/㎠, 8.0$\times$10 CFU/㎠ on the average. According to storage temperature, variations of number of TAB coliform were slight at 4$\^{C}$ but increased at 20$\^{C}$ and 30$\^{C}$ . Therefore following subjects can be issued on the basis of results. Minimize the storage time and keep at cool temperature. 1st and 2nd grinders should be managed hygienically. Establish the heating step during the production of instant action baby food. Instant ablactation baby food produced should be stored at cool and freeze condition.

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Development of remote control automatic fire extinguishing system for fire suppression in double-deck tunnel (복층터널 화재대응을 위한 원격 자동소화 시스템 개발 연구)

  • Park, Jinouk;Yoo, Yongho;Kim, Yangkyun;Park, Byoungjik;Kim, Whiseong;Park, Sangheon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.1
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    • pp.167-175
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    • 2019
  • To effectively deal with the fire in tunnel which is mostly the vehicle fire, it's more important to suppress the fire at early stage. In urban tunnel, however, accessibility to the scene of fire by the fire fighter is very limited due to severe traffic congestion which causes the difficulty with firefighting activity in timely manner and such a problem would be further worsened in underground road (double-deck tunnel) which has been increasingly extended and deepened. In preparation for the disaster in Korea, the range of life safety facilities for installation is defined based on category of the extension and fire protection referring to risk hazard index which is determined depending on tunnel length and conditions, and particularly to directly deal with the tunnel fire, fire extinguisher, indoor hydrant and sprinkler are designated as the mandatory facilities depending on category. But such fire extinguishing installations are found inappropriate functionally and technically and thus the measure to improve the system needs to be taken. Particularly in a double-deck tunnel which accommodates the traffic in both directions within a single tunnel of which section is divided by intermediate slab, the facility or the system which functions more rapidly and effectively is more than important. This study, thus, is intended to supplement the problems with existing tunnel life safety system (fire extinguishing) and develop the remote-controlled automatic fire extinguishing system which is optimized for a double-deck tunnel. Consequently, the system considering low floor height and extended length as well as indoor hydrant for a wide range of use have been developed together with the performance verification and the process for commercialization before applying to the tunnel is underway now.

Role of Police for Enhancement of Elderly Safety (노인안전 강화를 위한 경찰의 역할)

  • Cha, Min-Kyu;Kwack, Dae-Gyung
    • Korean Security Journal
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    • no.41
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    • pp.387-408
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    • 2014
  • South Korea already became an aging society, and is now in the process of becoming an aged society. With increasing elderly population, elderly safety issues such as traffic accidents and elderly suicides are becoming important problems. Elderly victimization are increasing, and elderly safety accident is also becoming an imporotant social problem. The police is doing various activities for elderly safety. The police is conducting programs for the elderly, such as a prevention program for fraud against elderly, and safety checks and traffic safety education for preventing elderly traffic accidents. Also, there's a program of providing regular visits for a lone elderly, expansion of CCTV network and fingerprint registration to prevent elderlies with Alzheimer's disease going missing. However, these programs are not done on a national scale, but rather limited to local police stations. The purpose of this study is to seek police roles for enhancing elderly safety, due to lack of police activity in this area. Recommendation for police roles in enhancing elderly safety is to first conduct routine crackdowns on fraud against elderly and also conduct education programs for preventing fraud. Also, crimes such as elderly abuse is lead by elderly protection agencies, but considering elderly abuse is a crime, the police should take a leading role. Also, to prevent elderly suicide, meticulous management of elderlies with high suicide risk is necessary, and elderly protection areas should be designated to prevent traffic accidents. Also, elderlies should be induced to turn in their driver's license. To conduct these matters of elderly safety, an organization exclusively charged with elderly safety is necessary. Elderly safety is a broad concept, and since police alone cannot handle the task of ensuring elderly safety, the police should take on a leading role in cooperative efforts with various institutions of the government, non-profit organizations and the community to establish a social saftey net for elderly safety.

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Synthesis and Electrochemical Performance of Ni-rich NCM Cathode Materials for Lithium-Ion Batteries (리튬이온전지 양극활물질 Ni-rich NCM의 합성과 전기화학적 특성)

  • Kim, Soo Yeon;Choi, Seung-Hyun;Lee, Eun Joo;Kim, Jeom-Soo
    • Journal of the Korean Electrochemical Society
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    • v.20 no.4
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    • pp.67-74
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    • 2017
  • Layered Ni-rich NCM cathode materials $Li[Ni_xCo_{(1-x)/2}Mn_{(1-x)/2}]O_2$ ($x{\geq}0.6$) have advantages of high energy density and cost competitive over $LiCoO_2$. The discharge capacity of NCM increases proportionally to the Ni contents. However, there is a problem that it is difficult to realize the stable electrochemical performance due to cation mixing. In this study, synthesis conditions for the layered Ni-rich NCMs are investigated to achieve deliver the ones having good electrochemical performances. Synthesis parameters are atmosphere, lithium source, synthesis time, synthesis temperature and Li/M (M=transition metal) ratio. The degree of cation mixing gets worse as the Ni content is increased from $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ (NCM6) to $Li[Ni_{0.8}Co_{0.1}Mn_{0.1}]O_2$ (NCM8). It is confirmed that higher level of cation mixing affects negatively on the electrochemical performance of NCMs. Optimum synthesis conditions are explored for NCMx (x=6, 7, 8) in order to reduce the cation mixing. Under optimized conditions for three representative NCMx, a high initial discharge capacity and a good cycle life are obtained for $180mAh{\cdot}g^{-1}$, 96.2% (50 cycle) in NCM6, $187mAh{\cdot}g^{-1}$, 94.7% (50 cycle) in NCM7, and $201mAh{\cdot}g^{-1}$, 92.7% (50 cycle) in NCM8, respectively.

Dehumidification and Temperature Control for Green Houses using Lithium Bromide Solution and Cooling Coil (리튬브로마이드(LiBr) 용액의 흡습성질과 냉각코일을 이용한 온실 습도 및 온도 제어)

  • Lee, Sang Yeol;Lee, Chung Geon;Euh, Seung Hee;Oh, Kwang Cheol;Oh, Jae Heun;Kim, Dea Hyun
    • Journal of Bio-Environment Control
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    • v.23 no.4
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    • pp.337-341
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    • 2014
  • Due to the nature of the ambient air temperature in summer in korea, the growth of crops in greenhouse normally requires cooling and dehumidification. Even though various cooling and dehumidification methods have been presented, there are many obstacles to figure out in practical application such as excessive energy use, cost, and performance. To overcome this problem, the lab scale experiments using lithium bromide(LiBr) solution and cooling coil for dehumidification and cooling in greenhouses were performed. In this study, preliminary experiment of dehumidification and cooling for the greenhouse was done using LiBr solution as the dehumidifying materials, and cooling coil separately and then combined system was tested as well. Hot and humid air was dehumidified from 85% to 70% by passing through a pad soaked with LiBr, and cooled from 308K to 299K through the cooling coil. computational Fluid Dynamics(CFD) analysis and analytical solution were done for the change of air temperature by heat transfer. Simulation results showed that the final air temperature was calculated 299.7K and 299.9K respectively with the deviation of 0.7K comparing the experimental value having good agreement. From this result, LiBr solution with cooling coil system could be applicable in the greenhouse.

Factors Affecting Problematic Drinking by University Students in Chuncheon Area (춘천지역 대학생의 문제음주에 영향을 미치는 요인)

  • Kim, Yoon-Sun;Kim, Bok-Ran
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.6
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    • pp.934-942
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    • 2014
  • The purpose of this study was to investigate factors affecting problematic drinking by university students in the Chuncheon area. Lifelong drinking rate of subjects was 98.1%. Problematic drinking rates according to AUDIT (alcohol use disorders identification test) were as follows: 21.3% 'no problem', 58.0% 'at-risk drinking', 10.0% 'alcohol abuse' and 10.7% 'alcohol dependence'. Research has shown that problematic drinking is more prevalent among freshmen, early drinkers, those with hypochondria, and students who are less satisfied with their campus life or whose own parents are frequent drinkers. It has been shown that more serious problematic drinking is associated with higher 'positive alcohol outcome expectancies' and 'coping motives for drinking', and 'recognition level of drinking cultures' is considered less desirable. Multiple regression analysis revealed that 'coping motives for drinking' was the most significant variable affecting the problematic drinking of university students. Developing and fostering various alcohol-reducing programs that largely focus on 'coping motives for drinking' will greatly contribute to solving problematic drinking.

Jeju Shinyang Fishing Port Remodeling Plan Utilizing Marine Tourism Resources (해양관광자원을 활용한 제주 신양항 리모델링 계획)

  • Kim, Yelim;Sung, Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.2
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    • pp.52-69
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    • 2016
  • The fishing port was once the foothold of production as well as the stronghold of communities but with the declining of the fishing industry, ports became abandoned space. Jeju Special Self-Governing Province has continued its effort to vitalize marine tourism since 2010. Shinyang Port in particular is designated as a Prearranged Marina Port Development Zone, and planning for the Jeju Ocean Marina City project is underway. Nevertheless, fishing port remodeling projects implemented on Jeju so far have focused only on civil engineering such as renovating old facilities. In addition, most Marina Port Development Projects have been irrelevant to local communities. Leading projects by the local government mostly suffer from a lack of funding, which results in the renovation of old facilities and improper maintenance, while private sector investment projects do not lead to benefit sharing with the community. Shinyang Port, also renovated in 2008, ended up with outer breakwater extension construction that neither solved the fundamental problem of the site nor gave benefits to residents. To arrange a way to solve problems for civil engineering focused development project, improper maintenance, and benefit sharing with community, first, this study proposes a development plan that connects with the outlying areas near the ports. The plan reflects existing topography, Jeju traditional stonewalls, narrow paths on the master plan and programs by reading the regional context. In this way, this paper suggests a space development plan reflecting the local landscape and characteristic factors. Second, it satisfies various needs by using existing and new Marine Tourism Resources. Third, it examines sustainable operation and management measures through residents' participation. The proposal is significant in two key ways: it is a fresh attempt at connecting the fishing port with its outlying areas from a landscape perspective; and it considers environmental, social, economic issues, and suggests participation for local communities. Thus, the model can be used in future fishing-port remodeling plans for revitalizing unused space, including invaluable traditional landscapes, and for boosting the marine-leisure industry.

A Study on the Serialized Event Sharing System for Multiple Telecomputing User Environments (원격.다원 사용자 환경에서의 순차적 이벤트 공유기에 관한 연구)

  • 유영진;오용선
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.344-350
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    • 2003
  • In this paper, we propose a novel sharing method ordering the events occurring between users collaborated with the common telecomputing environment. We realize the sharing method with multimedia data to improve the coworking effect using teleprocessing network. This sharing method advances the efficiency of communicating projects such as remote education, tele-conference, and co-authoring of multimedia contents by offering conveniences of presentation, group authoring, common management, and transient event productions of the users. As for the conventional sharing white board system, all the multimedia contents segments should be authored by the exclusive program, and we cannot use any existing contents or program. Moreover we suffer from the problem that ordering error occurs in the teleprocessing operation because we do not have any line-up technology for the input ordering of commands. Therefore we develop a method of retrieving input and output events from the windows system and the message hooking technology which transmits between programs in the operating system In addition, we realize the allocation technology of the processing results for all sharing users of the distributed computing environment without any error. Our sharing technology should contribute to improve the face-to-face coworking efficiency for multimedia contents authoring, common blackboard system in the area of remote educations, and presentation display in visual conference.

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A Meta-Analysis on the Effects of Integrated Education Research (통합교육의 효과에 대한 메타분석)

  • Kim, Jiyoung;Park, Eunmi;Park, Jieun;Bang, Dami;Lee, Yoonha;Yoon, Heojoeng
    • Journal of The Korean Association For Science Education
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    • v.35 no.3
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    • pp.403-417
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    • 2015
  • The purpose of this study was to investigate the effectiveness of integrated education research conducted in Korea and to propose a meaningful discussion for further research. Among the studies conducted for last three years, the relevant 161 research articles were selected, and 236 effect sizes were calculated. Effect sizes were analyzed with different dependant variables including creativity, problem solving ability, academic achievement, inquiry skills, creative personality, scientific attitude, and interests. In addition, effect sizes with different moderating variables, such as characteristics of subjects, sample sizes, class types, core disciplines and publication types, were compared. The results are as follows: The overall effect size of integrated education program produced a huge effect (effect size=0.88, U3=81.06%). Integrated education program showed the highest effect size on scientific attitude among other dependant variables. However, all of the other dependant variables represented more than medium size effect size. Integrated program proved to be more effective on kindergarten pupils and gifted students compared to other school levels and regular students. The effect size for group of less then thirty students were larger than other groups. Programs implemented in after school hours were more effective than in regular school hours. Considering the core subject of program, arts-centered integrated programs showed the largest effect size, while all the others showed above medium effect sizes. Finally, doctoral dissertation showed the highest effect size compared to master's thesis and academic journal articles. Conclusions and recommendations for further research were provided.