• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.241-247
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• 2013

AOAC Mouse Bioassay Analysis (MBA) has been the gold standard for the analysis of paralytic shellfish poisoning toxin (PSP toxin) for more than 50 years. However, this method has inaccurate limit of quantification and cannot be used to determine toxic profiles. An HPLC method (PCOX) was optimized for Korean shellfish to establish an alternative or supplementary method for PSP analysis and was intended to be used for the official monitoring and regulation of food. The recovery rate of the PCOX method was 83.5-112.1% and the limit of quantification for total toxin was about $8.6{\mu}g$/100 g. A long-term comparison study showed a good correlation of the PCOX results with the AOAC MBA results: the correlation factors were 0.9534 and 0.9109 for oyster and mussel matrices, respectively. The PCOX method may be used as an alternative or supplementary method for AOAC MBA to monitor the occurrence of PSP and to analyze PSP toxin profile in oysters and mussels.

• Archives of design research
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• v.17 no.4
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• pp.177-190
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• 2004

The purpose of this study is to provide domestic small and medium manufacturing businesses with effective ways of introducing and promoting design management, earnestly, as a key strategy for raising corporate competitiveness. For the purpose, this researcher discussed the management property of small and medium businesses, the introducing process and method and the necessity of promoting design management in small and medium businesses. Then the researcher reviewed and analyzed existing empirical studies to know the current status of design introduction and design management promotion i domestic small and medium businesses. Results of the study can be described as below. Prerequisite to the successful introduction by domestic small and medium businesses of design management are three CEO determinations - the firm will to the necessity of design introduction, the firm conviction in design efficacy, and the clear recognition of the existential value of design - and the establishment of at least five infrastructures -design organization, CDO, designers, design policy, and design strategy. For the promoting and succeeding in the execution of design management, design management system should have established based on such determinations and infrastructures, and CEOs should have design management mind firmly established and driven and realized next activities in the process of product development. 1) Set the principle of design priority in a new product development and establish an appropriate production system and environment. 2) Decide a new design development as the top-priority task of management and then practice it in a strategic way. 3) Be positive in design investment while accepting design management as a concept related not to cost, but to investment. 4) Utilize design extensively under the understanding that design management has something to do with corporate design system as a whole. 5) Treat design as the most valuable resource of business under the recognition that design is the most important determinant of corporate competitiveness.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.227-231
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• 2010

Slurry composting biofiltration(SCB) is considered as a treatment to produce a better fertilizer resource than raw pig slurry as it reduces odor and improves nutrients imbalance. For the agricultural use of SCB slurry as a nutrient source with minimum environmental impact, it is important to investigate the effect of different rate of SCB slurry application on nutrient (particularly for nitrogen) uptake and growth of crops. This study was conducted to investigate the influence of fertigation using pig slurry(PS) on growth and yield of red pepper and to evaluate the appropriate PS concentration in fertigation for soils with different nitrate concentration. To evaluate the effects of fertigation applied PS as a substitute of chemical fertilizer(CF), a single application of three different concentrations of PS: $N_{0.5}$ (43 mg/L), $N_{1.0}$ (86 mg/L) and $N_{1.5}$ (131 mg/L) were compared with CF $N_{1.0}$ (89 mg/L) as a control nitrogen fertilizer. Statistical analysis showed that the growths of red pepper were not affected by treatments. In addition, the yields were no significant difference among treatments, though the highest yield was obtained in PS $N_{1.0}$ by 20,580 kg/ha. In soil chemical properties, nitrate nitrogen on soil of between PS N1.0 and CF $N_{1.0}$ treatment showed similar patterns although they were higher than the preplant nitrogen content. Also, there was no significant difference in yield of red pepper between PS and CF treatment applied as fertigation on soils where nitrate nitrogen contents of each soil contains 10, 100 and 200 mg/kg respectively. Consequently, the application of PS, such as SCB, as a substitute of CF is available for growth and yield of red pepper, there could be accordingly estimated the optimal fertigation concentration of PS for red pepper cultivation.

• Journal of Environmental Impact Assessment
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• v.29 no.2
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• pp.79-92
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• 2020

This study aimed at analyzing the current status and further needs of ecological information which is provided with the civil servants in the process of climate change adaptation planning in ecosystem sector and at providing suggestions for future development of ecological knowledge on climate change. Therefore, we conducted a questionary survey titled as "the knowledge-base and information needs for climate change adaptation in ecosystem sector" with the civil servants who are engaged with adaptation practices in the ecology related divisions in 17 regional local governments (RLG) and the affiliated basic local governments (BLG) in Korea. As a result, the characteristics of ecological information which is applied in public practices was analyzed and strategies for improved utilization was suggested. 75% of the respondents (RLG 85% and BLG 72%) were aware of the relativeness between the existence and utilization of ecological information and the execution of climate adaptation practices in ecosystem sector. They were agreed with the necessity of ecological information not only in adaptation practices but also overall affairs in the ecological related division in the local government (RLG 82% and BLG 72%). The current situation of utilizing ecological information which is produced from central orlocal government to civil affairs were only represented as 64 persons (28%) in RLG and 42 persons (18%) in BLG. One of the major obstacles that the respondents confront with when applying ecological information to public practices was deficit of prior knowledge on the ecological information itself, such as awareness of the characteristics of ecological information and the link with public affairs for adaptation plans. Therefore, delivering current knowledge and ecological information on climate change by educational and promotional method is an urgent priority to the civil servant. The future needs on ecological information for local government servants were deduced as basic information on local ecosystem and applied knowledge on local development to meet the biodiversity conservation and ecosystem services at the same time. The respondents expected not only the specific guidelines for using ecological information to apply on the adaptation plans in the relevant divisions of the local governments but also the institution where the usage activation of ecological information would be operated and managed to enhance the information utilizing structure in the local government. In the nation-wide, the capacity of local governments should be enhanced with adaptation knowledge and the application of appropriate information to the public practices by central government's aiding with the better quality of information, its public promotion, and the applicability to civil affairs.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.8-12
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• 2010

Purpose: In $^{18}F$-FDG automated synthesizer, deliver is done in automated mode after synthesis until the dispenser. After the delivery, the yield is calculated from the radioactivity which was read by the dose calibrator located in the dispenser. However, when the distance between the automated synthesizer and the dispenser is far, there are $^{18}F$-FDG residues, which results in loss of the amount of $^{18}F$-FDG. This study investigated the usefulness of a method that minimizes $^{18}F$-FDG residues. Materials and Methods: The structure of the tubing between the (TRACERlab Mx FDG; GE.) and the dispenser is that the distance is 8 m and the internal diameter is 1/16 inch. The synthesis process of The module goes through the synthesis process of trap, synthesis, delivery in the automated module. The time taken for synthesis is about 25 to 26 minutes, after which rinsing is done. However, after rinsing, as the distance of the tubing increased, there were 10~13% of $^{18}F$-FDG residues. Therefore, a method of using push syringe and $N_2$ gas in manual mode to minimize $^{18}F$-FDG residues is analyzed. Results: In manual mode, there were $^{18}F$-FDG residues of 4~5% for the push syringe, and there were $^{18}F$-FDG residues of less than 1% for the $N_2$ gas, which showed that the method using $N_2$ gas had superior usefulness. Also, there were no $^{18}F$-FDG residues in the cleaning the next day. Conclusion: The distance between the synthesizer and the dispenser needs to be reduced as much as possible, to reduce the rate of loss of $^{18}F$-FDG resulting from the distance of the tubing. However, in case the distance between the synthesizer and the dispenser has to be increased due to the system structure, using push syringe and $N_2$ gas simultaneously is a useful method for minimizing $^{18}F$-FDG residues.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.153-158
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• 2003

Purpose : The incidence of hepatitis B virus infection has gradually decreased since 1983 when hepatitis B vaccine was firstly produced. This study was performed to evaluate the efficacy of hepatitis B immunization. Methods : The elementary, middle and high school children in Incheon area were enrolled in this study in 1997 and 1998. Hepatitis B virus surface antigen(HBsAg) was measured using reversed passive hemagglutination(RPHA). Results : The results were as follows The positive rates of HBsAg in elementary, middle and high school children were 0.7%(337/46,861), 2.5%(381/15,026) and 3.1%(681/21,938) respectively in 1997 and 0.6%(257/41,946), 2.7%(379/13,652) and 2.4%(628/25,277) respectively in 1998. The positive rates of HBsAg in children under 19 years of age in 1985, 1990 and 1995 were 6.1, 5.2 and 3.5% respectively. Conclusion : The positive rates of HBsAg in elementary school children in 1997 and 1998 has decreased compared with those of the previous studies. The majority of elementary school children were given hepatitis B vaccination. These results suggest that hepatitis B vaccines used in Korea were effective for prevention of hepatitis B infection in school children.

• The Magazine of the IEIE
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• v.29 no.6
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• pp.76-80
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• 2002

'Liquid Crystal의 상전이(相轉移)와 광학적 이방성(異方性)이 1888년과 1889년 F. Reinitzer와 O. Lehmann에 의해 Monatsch Chem.과 Z.Physikal.Chem.에 각각 보고된 후 부터 제2차 세계대전이 끝난 뒤인 1950년대 까지는 Liquid Crystal을 단지실험실에서의 기초학문 차원의 연구 대상으로만 다루어 왔다. 1963년 Williams가 Liquid Crystal Device로는 최초로 특허 출원을 하였으며, 1968년 RCA사의 Heilmeier등은 Nematic 액정(液晶)에 저주파(低周波) 전압(電壓)을 인가하면 투명한 액정이 혼탁(混濁)상태로 변화하는 '동적산란(動的散亂)'(Dynamic Scattering) 현상을 이용하여 최초의 DSM(Dynamic Scattering Mode) LCD(Liquid Crystal Display)를 발명하였다. 비록 150V 이상의 높은 구동전압과 과소비전력의 특성 때문에 실용화에는 실패하였지만 Guest-Host효과와 Memory효과 등을 발견하였다. 1970년대에 이르러 실온에서 안정되게 사용 가능한 액정물질들이 합성되고(H. Kelker에 의해 MBBA, G. Gray에 의한 Cyano-Biphenyl 액정의 합성), CMOS 트랜지스터의 발명, 투명도전막(ITO), 수은전지등의 주변기술들의 발전으로 인하여 LCD의 상품화가 본격적으로 이루어지게 되었다. 1971년에는 M. Shadt, W. Helfrich, J.L. Fergason등이 TN(Twisted Nematic) LCD를 발명하여 전자 계산기와 손목시계에 응용되었고, 1970년대 말에는 Sharp에서 Dot Matrix형의 휴대형 컴퓨터를 발매하였다. 이러한 단순 구동형의 TN LCD는 그래픽 정보를 표시하는 데에는 품질의 한계가 있어 1979년 영국의 Le Comber에 의해 a-Si TFT(amorphous Silicon Thin Film Transistor) LCD의 연구가 시작되었고, 1983년 T.J. Scheffer, J. Nehring, G. Waters에 의해 STN(Super Twisted Nematic) LCD가 창안되었고, 1980년 N. Clark, S. Lagerwall 및 1983년 K.Yossino에 의해 Ferroelectric LCD가 등장하여 LCD의 정보 표시량 증대에 크게 기여하였다. Color화의 진전은 1972년 A.G. Ficher의 셀 외부에 RGB(Red, Green, Blue) filter를 부착하는 방안과, 1981년 T. Uchida 등에 의한 셀 내부에 RGB filter를 부착하는 방법에 의해 상품화가 되었다. 1985년에는 J.L. Fergason에 의해 Polymer Dispersed LCD가 발명되었고, 1980년대 중반에 이르러 동화상(動畵像) 표시가 가능한 a-Si TFT LCD의 시제품(試製品) 개발이 이루어지고 1990년부터는 본격적인 양산 시대에 접어들게 되었다. 1990년대 초에는 STN LCD의 Color화 및 대형화(大型化) 고(高)품위화에 힘입어 Note-Book PC에 LCD가 본격적으로 적용이 되었고, 1990년대 후반에는TFT LCD의 표시품질 대비 가격경쟁력 확보로 인하여 Note-Book PC 시장을 독점하기에 이르렀다. 이후로는 TFT LCD의 대형화가 중요한 쟁점으로 부각되고 있고, 1995년 삼성전자는 당시 세계최대 크기의 22' TFT LCD를 개발하였다. 또한 LCD의 고정세(高情細)화를 위해 Poly Si TFT LCD의 개발이 이루어졌고, 디지타이져 일체형 LCD의 상품화가 그 응용의 폭을 넓혔으며, LCD의 대형화를 위해 1994년 Canon에 의해 14.8', 21' 등의 FLCD가 개발되었다. 대형화 방안으로 Tiled LCD 기술이 개발되고 있으며, 1995년에 Sharp에 의해 21' 두장의 Panel을 이어 붙인 28' TFT LCD가 전시되었고 1996년에는 21' 4장의 Panel을 이어 붙인 40'급 까지의 개발이 시도 되었으며 현재는 LCD의 특성향상과 생산설비의 성능개선과 안정적인 공정관리기술을 바탕으로 삼성전자에서 단패널 40' TFT LCD가 최근에 개발되었다. Projection용 디스플레이로는 Poly-Si TFT LCD를 이용하여 $25'{\sim}100'$사이의 배면투사형과 전면투사형 까지 개발되어 대형 TV시장을 주도하고 있다. 21세기 디지털방송 시대를 맞아 플라즈마디스플레이패널(PDP) TV, 액정표시장치 (LCD)TV, 강유전성액정(FLCD) TV 등 2005년에 약 1500만대 규모의 거대 시장을 형성할 것으로 예상되는 이른바 '벽걸이TV'로 불리는 차세대 초박형 TV 시장을 선점하기 위하여 세계 가전업계들이 양산에 총력을 기울이고 있다. 벽걸이TV 시장이 본격적으로 형성되더라도 PDP TV와 LCD TV가 직접적으로 시장에서 경쟁을 벌이는 일은 별로 없을 것으로 보인다. 향후 디지털TV 시장이 본격적으로 열리면 40인치 이하의 중대형 시장은 LCD TV가 주도하고 40인치 이상 대화면 시장은 PDP TV가 주도할 것으로 보는 시각이 지배적이기 때문이다. 그러나 이러한 직시형 중대형(重大型)디스플레이는 그 가격이 너무 높아서 현재의 브라운관 TV를 대체(代替)하기에는 시일이 많이 소요될 것으로 추정되고 있다. 그 대안(代案)으로는 비교적 저가격(低價格)이면서도 고품질의 디지털 화상구현이 가능한 고해상도 프로젝션 TV가 유력시되고 있다. 이러한 고해상도 프로젝션 TV용으로 DMD(Digital Micro-mirror Display), Poly-Si TFT LCD와 LCOS(Liquid Crystals on Silicon) 등의 상품화가 진행되고 있다. 인터넷과 정보통신 기술의 발달로 휴대형 디스플레이의 시장이 예상 외로 급성장하고 있으며, 요구되는 디스플레이의 품질도 단순한 문자표시에서 그치지 않고 고해상도의 그래픽 동화상 표시와 칼라 표시 및 3차원 화상표시까지 점차로 그 영역이 넓어지고 있다. <표 1>에서 보여주는 바와 같이 LCD의 시장규모는 적용분야 별로 지속적인 성장이 예상되며, 새로운 응용분야의 시장도 성장성을 어느 정도 예측할 수 있다. 따라서 LCD기술의 연구개발 방향은 크게 두가지로 분류할 수 있으며 첫째로는, 현재 양산되고 있는 LCD 상품의 경쟁력강화를 위하여 원가(原價) 절감(節減)과 표시품질을 향상시키는 것이며 둘째로는, 새로운 타입의 LCD를 개발하여 기존 상품을 대체하거나 새로운 시장을 창출하는 분야로 나눌 수 있다. 이와 같은 관점에서 현재 진행되고 있는 LCD기술개발은 다음과 같이 분류할 수 있다. 1) 원가 절감 2) 특성 향상 3) New Type LCD 개발.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.414-420
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• 2020

This study was carried out to investigate the growth characteristics of standard chrysanthemum 'Baekma', such as fresh weight, dry weight, and leaf area and to develop prediction models for the production greenhouse based on the growth parameters and climatic elements. Sigmoid regressions models for the prediction of growth parameters in terms of dry weight and leaf area were analyzed according to the number of the day after transplanting and the accumulate temperature during this experimental period. The relative growth rate (RGR) of the chrysanthemum was 0.084 g·g^-1·d^-1 on average during the period.The dry weight and leaf area of 'Beakma' increased exponentially according to the number of day after transplanting and the accumulated temperature, in the case of dry weight increased by an average of 39.1% until 63 days (accumulated temperature of 1601℃), after that dry weight increased by an average of 7.4% before harvest. The leaf area increased by an average of 63.3% until the 28th day after transplanting, and by an average of 6.5% until the 84th day before flower bud differentiation occurred, and increased by an average of 10.6% before harvest. This experiment can be used as a useful data for establishing a cultivation management system and a planned year-round production system for standard chrysanthemum "Baekma". To make a more precise growth prediction model, it will need to be corrected and verified based on various weather data including accumulated irradiation.

• Information Systems Review
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• v.11 no.1
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• pp.161-179
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• 2009

Nowadays an increasing number of Internet users are running individual websites as Blog or Cyworld. As this type of personal media has a great influence on communication among people, business comes to care about Network Effect, Network Software, and Social Network. For instance, Cyworld created the web service called 'Minihompy' for individual web-logs, and acquired 2.4milion users in 2007. Although many people assumed that the popularity of Minihompy, or Blog would be a passing fad, Cyworld has improved its service, and expanded its Network with various contents. This kind of expansion reflects survival efforts from infinite competitions among ISPs (Internet Service Provider) with focus on enhancing usability to users. However, Cyworld's Network Effect is gradually diminished in these days. Both of low production cost of service vendors and the low searching/conversing costs of users combine to make ISPs hard to keep their market share sustainable. To overcome this lackluster trend, Cyworld has adopted new strategies and try to lock their users in their service. Various efforts to improve the continuance and expansion of Network effect remain unclear and uncertain. If we understand beforehand how a service would improve Network effect, and which service could bring more effect, ISPs can get substantial help in launching their new business strategy. Regardless many diverse ideas to increase their user's duration online ISPs cannot guarantee 'how the new service strategies will end up in profitability. Therefore, this research studies about Network effect of Cyworld's 'Minihompy' using System-Dynamics method which could analyze dynamic relation between users and ISPs. Furthermore, the research aims to predict changes of Network Effect based on the strategy of new service. 'Page View' and 'Duration Time' can be enhanced for the short tenn because they enhance the service functionality. However, these services cannot increase the Network in the long-run. Limitations of this research include that we predict the future merely based on the limited data. We also limit the independent variables over Network Effect only to the following two issues: Increasing the number of users and increasing the Service Functionality. Despite of some limitations, this study perhaps gives some insights to the policy makers or others facing the stiff competition in the network business.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.33-45
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• 2009

In the industry of landscape architecture, in which the core of production is manpower, the management of manpower is of utmost importance. The industry of landscape architecture, however, is highly sensitive to economic shifts and policy changes; this sensitivity renders the management of manpower-maintaining the balance between supply and demand-often times difficult. Currently, this vicious circle appears to persist in the sense that the industry suffers from a lack of skilled employees, and a new body of skilled laborers from the paucity of jobs. This study, in analyzing current manpower management as well as the prospective supply and demand in the field, looks forward to the stability of the supply and demand in landscape architecture in the nation. According to this study, the number of new skilled laborers-those who have a higher credential than that of "landscape architect-engineer"-is expected to increase by 10% per year. The number of new skilled laborers being 1,137 in 2008, it can be inferred that there will be a new group of 1,251 skilled laborers in the field in 2009. Meanwhile, estimating that the number of current skilled laborers in the field of landscape architecture is 14,783, the demand for new skilled laborers remains approximately 540. The supply of 1,251 skilled laborers outnumbers the demand of 540 by nearly 230%. Hence, the educational institutions of landscape architecture must be prepared to deal with this imbalance between the excessive supply and the lesser demand of skilled laborers. The issue of the excessive supply of manpower is particularly critical, because it may well undermine the competitiveness of the industry as a whole: compared to other related industries such as architecture and civil engineering, for instance. With the customary validation of long work experience no longer in effect, the need for an engineer's license will keep on increasing. It is time that educational institutions took this issue into full account and helped their students to be better qualified and more competent.