• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.10a
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• pp.1-2
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• 1999

시간과 공간의 구애를 받지 않는 양질의 음성, 화상, 문자정보의 교환을 위한 노력으로 디지털 휴대폰과 휴대용 컴퓨터가 등장하면서 음성과 문자정보의 교환분야에 커다란 진보를 이룩하였다. 그러나 현재는 휴대폰이 음성정보에 문자정보교환이 추가된 상황이기 때문에, 아직도 관련 정보교환기술 및 기기개발이 진행되고 있다. 앞으로 휴대폰과 휴대용 컴퓨터의 기능을 통합하고 화상정보까지 결합된 휴대용 정보기기를 위해서는 전자회로의 집적화 및 통신속도 증대가 필수적이다. 또한 이들 휴대용 정보기기를 구동시키기 위한 전력도 증가될 것으로 예측되기 때문에, 현재 전원으로 사용되는 2차전지보다 에너지 밀도가 더욱 증패된 전지가 요구될 것으로 예상된다. 그리고 내연기관의 배기에 의해 발생되는 환정오염문제를 해결하기 위한 방법중의 일환으로 전기자동차 개발이 진행되고 있으며, 이들 전기자동차에 2차전지를 장착하기 위해서 경제성이 있고, 고속충전이 가능하고, 안전성이 높은 고에너지 밀도의 2차 전지 개발이 요구되고 있다. 현재 2차전지는 음극재료나 양극재료에 따라 낚축전지, 니켈/카드륨(Ni/Cd) 전지, 니켈/수소(Ni/MH) 전지, 라륨 2 차전지등이 있으며, 전극재료의 고유특성에 의해 전위와 애너지 밀도가 결정된다. 특히 리튬 2차전지는 리튬의 낮은 산화환원전위와 분자량으로 인해 에너지 밀도가 높기 때문에 앞에서 언급한 휴대용 전자기기의 구동전원으로 많이 사용되고 있다. 리튬 2차전지는 음극 재료가 금속리튬인 경우는 리튬금속으로, 탄소재료인 경우는 리튬이온이라 하며, 한편으로 전해질이 고체 고분자이거나 혹은 역체 유기용매와 리튬염을 고분자와 혼성시킨 겔(gel)인 경우는 고분자로, 전해짙이 리튬염이 전리되어 있는 유동성 액체일 경우는 고분자를 생략하여 구분하고 있다. 즉 리튬금속 2 차전지(LB), 리튬이온 2 차전지(LIB), 리튬금속 고분자 2차전지(LPB), 리튬 이온 고분자 2차전지(LIPB)로 크게 구분된다. 금속리듐을 음극으로 사용하고 전해질로는 리튬염이 전리되어 있는 액체유기용매 를 사용한 리튬금속 2차전지는, 금속리튬전극이 충방전 과정을 반복하면서, 전리된 리튬이 균일하게 산화환원되지 못하고 표변에서 양극방향으로 성장하는 수지상 (dendrite) 현상으로 인해 안전성 확보에 문게가 있었다. 리튬과 알루미늄 합금형태로 음극에 사용한 동전형 전지는 상용화 되었지만, 이러한 단점을 개선하기 위해 리튬이온이 금속으로 석활되는 환원반응전위보다 높은 전위에서 전극재료가 충전되면서 리튬이온이 저장되고, 방전되면서 배출되는 탄소를 음극재료로, 그리고 리튬이온이 충방 전시 가역적으로 삼입 탈리되는 층상의 리튬금속산화물을 양극으로 구성하고, 엑체 전해질과 다공성 고분자 분리막을 사용한 것이 LIB이다. LIB에서 리튬이온의 이동이 가능한 액체전해질의 가능을 고분자 전해질이 대신함으로서 보다 높은 안정성을 확보 한 전지가 LIPB 이다. 또한 고분자 전해질을 사용한 경우 금속리튬상에서의 수지상 성장이 저하되는 현상이 관찰됨으로서, 이론용량이 3,860mAh/g 에 달하는 리튬금속 혹은 합금을 고분자 전지에서 음극으로 사용하고자 하는 2 차전지가 LPB 이다. 리튬 2차전지는 비록 1989년 액체전해질을 사용한 금속리튬 2차전지의 실패전력을 안고있지만 궁극적으로는 이론적으로 최대의 에너지밀도를 가지고 있는 LPB를 지 향할 것으로 예상되지만 가까운 장래에 실현되기는 어려울 것이다. 따라서 향후의 라튬 2차전지의 전개방향은 현재의 LIB를 고분자 전해질을 채용하는 LIPB로 진행시커면서 저가의 전극재료개발을 지속적으로 추진할 것으로 예상된다. 현재 리튬 2차전지는 소형전지에 국한되고 있지만 전기자동차나 전력저장용으로 이를 대형화시커기 위해서는 열적특성이 우수하고 저가인 전극재료개발이 선행되야하기 때문에, 저가의 탄소재료와 코발트산화물을 대신할 수 있는 철, 망칸 또는 니켈산 화물의 개발이 필요하다.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.59-70
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• 2021

This paper studies and analyzes the effect of illustrations in picture books on time representation with fictional picture books as the study scope. In this paper, the time type of picture books can be divided into time point, timeline and time rhythm, referring to case analysis from time symbolic elements, picture layout and picture sequence respectively. First of all, time symbolic elements are referred to the time point and time rhythm. The materialized time symbolic element is things that can directly represent time and trigger associations with time; the color symbolic element means the color changes in the real world within a certain time; the contrast of light and shadow corresponds to the changes in a day. Fast-moving objects will be presented with dashed or blurred lines, while static, stable and slow objects will be depicted with solid lines. Secondly, the picture layout of illustrations in picture books is suitable for representing the content of the timeline and describing the sequence or causality of events. Finally, the picture sequence can represent the timeline, time rhythm and "synchronicity". It will make use of visual logic to win readers' trust in time information expressed in pictures, and then follow and connect viewpoints on the basis of adapting to reading habits. The essence of time representation in picture books is to express time by space, and use different combinations of elements in space and visual guidance to convey time information.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.5
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• pp.1-14
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• 2023

Soybeans are one of the world's top five staple crops and a major source of plant-based protein. Due to their susceptibility to climate change, which can significantly impact grain production, the National Agricultural Science Institute is conducting research on crop phenotypes through growth analysis of various soybean varieties. While the process of capturing growth progression photos of soybeans is automated, the verification, recording, and analysis of growth stages are currently done manually. In this paper, we designed and trained a YOLOv5s model to detect soybean leaf objects from image data of soybean plants and a Convolution Neural Network (CNN) model to judgement the unfolding status of the detected soybean leaves. We combined these two models and implemented an algorithm that distinguishes layers based on the coordinates of detected soybean leaves. As a result, we developed a program that takes time-series data of soybeans as input and performs growth analysis. The program can accurately determine the growth stages of soybeans up to the second or third compound leaves.

• Broadcasting and Media Magazine
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• v.11 no.4
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• pp.104-117
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• 2006

In this Paper, we analyze the application of Interactive Data Broadcasting in DMB(Digital Multimedia Broadcasting) in the accordance with convergence of service and technology. With the acceleration of digital convergence in the Ubiquitous period substantial development of digital media technology and convergence of broadcasting and telecommunication industry are being witnessed. Consequently these results gave rise to newly combined-products such as DMB(Digital Multimedia Broadcasting), WCDMA(Wide-band code division multiple access), Wibro(Wireless Broadband Internet), IP-TV (Internet protocol TV) and HSDPA(High speed downlink packet access). The preparatory stage for the implementation of Interactive Data Broadcasting Service will be reached by the end of December, 2006. DMB is the first result of a successful convergence service between Broadcasting and Telecommunication in new media era. Multimedia technology and services are the core elements of DMB. The Data Broadcasting will not only offer various services of interactive information such News, Weather, Broadcasting Program etc, but also be linked with characteristic function of mobile phone such as calling and SMS(Short Message Service) via Return Channel.

• Korean Journal of Plant Tissue Culture
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• v.22 no.1
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• pp.47-51
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• 1995

This study was conducted to investigate the possibility of obtaining platelets via somatic embryogenesis as a means of in vivo mass propagation in Paeonia lactiflora Pall.. When cultured on MS medium with 0.5 mg/L 2, 4-D, filament explants formed calli. UPon transfer to basal medium the calli gave rise to somatic embryos at a frequency of 38%. Additional of 3g/L activated charcoal enhanced the frequency to 60%. Mature embryos preheated at 5$^{\circ}C$ for 2 weeks had 37% germination on medium with 0.3 mg/L GA$_3$. The germinated embryos developed to complete plantlet when cultured on medium with 2mg/L BA.

• KSBB Journal
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• v.11 no.5
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• pp.606-612
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• 1996

A specific ammino auid in a mixture can be crystallized inside an ion exchange column when displacer concentration is high enough to concentrate the amino acid in a pure band beyond its solubility limit. Glutamic acid formpd a discrete crystal layer in a cation exchanger column by operating displacement development mode and using a high concentration of displacer NaOH. The glutamic acid crystal formed was eluded from the column with the effluent stream and collected in a fraction collector. When 1.0 M of NaOH was used as a displacer, more than 60% of the loaded glutamic acid was recovered as crystal. The continuous crystallization and dissolution of crystal occurred, resulting in apparent movement of the crystal along the column without clogging or pressure increase. NaOH was proved a better displacer than NaCl because hydroxide ions neutralized hydrogen ions released from the resin and thus reduced the number of hydrogen ion competing with sodium ion for re-adsorption. The displacement development process coupled with crystallization provided higher concentration and recovery of glutamic acrid than conventional chromatography.

• Journal of the Economic Geographical Society of Korea
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• v.23 no.1
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• pp.56-70
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• 2020

This study identifies the impact of social network service (SNS) on the spatial characteristics of retail stores locations in the hyper-connected society, which have been closely related to the everyday lives of urban residents. In particular, we focus on the changes in the spatial distribution of restaurants since the information retrieval process was added to the decision-making process of a consumer's restaurant selection. Empirically, we analyze restaurants in Seoul, Korea since the smart-phone was introduced. By applying the kernel density estimation and Moran's I index, we examine the changes in the spatial distribution pattern of restaurants during the last ten years for running, newly-open and closed restaurants as well as SNS popular ones. Finally, we develop a spatial regression model to identify geographic features affecting their locations. As the results, we identified geographical variables and online factors that influence the location of restaurants. The results of this study could provide important groundwork for food and beverage location planning and policy formulation.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.53-61
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• 2009

The present experiment was conducted to examine the effects of mycelia of Cordyceps militaris cultured from grains on cordycepin deposition in muscles and plasma glutathione peroxidase activity in finishing Hanwoo steers. Four steers were divided into two groups. Control group received no supplement whereas treatment group received 1 % mycelia of C. militaris of their feed intake for 80 days prior to slaughtering. Final body weight, average daily gain, dry matter intake were not affected by the treatment. But the activity of plasma glutathione peroxidase was numerically higher for the treatment group than for the control group (15.70 vs 9.23 unit). Furthermore, cordycepin deposition in muscles on the treatment group was identified with thin layer chromatography. The results of the present experiment show that cordycepin could be deposited in muscles of Hanwoo beef by feeding mycelia of Cordyceps militaris cultured from grains.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.14 no.2
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• pp.63-68
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• 1978

A boat seine has been used as a major fishing gear for catching anchovy (Engraulis japonica) in the southern coastal waters of Korea since the 1920s. Since the 1950s some improvement from the original seine has been made; powered boats equipped with net hauler has been used instead of rowing boats with hand-driven capstan, and the seining method has been changed into the trawling method. But even now, there are many problems to be solved in the view point of decreasing man power without decreasing catching efficiency. For the purpose, patti-net has been introduced from Japan and experimented on the commercial base since 1972, and it was known that the patti-net could be operated with man power as half as needed in the coventional net, but catching efficiency was not so desirable. Therefore, the study on the characteristics of it were required. The authors carried out a model experiment with a Qne-twentieth scale model net towed by a powered boat on the sea. The obtained results run as follows: 1. Hydrodynamic resistance of the model net can be explained as $R_p=69.6 V_{I.66}$ $R_h=37 v^2$ where $R_p$ and $R_b$ denote the resistance of the whole gear and the cod end in kg respectively, and v the towing speed in mlsec. 2. Performance of wing and cod end showed no deformation such as observed at the conventional net. 3. The ratio of opening at the entrance of bag net to that of cod end showed about 2: 1. Therefore, when we intend to enlarge the net to be able to operate in the deep fishing ground, the cod end should be enlarged in the same proportion and increased towing power is needed .. Then, it will be better to increase the ratio for increasing fishing efficiency without increasing towing power.

• The Journal of Korean Philosophical History
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• no.23
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• pp.7-65
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• 2008

The object of this essay is to apply the Leadership Theory, current interest in Asian Philosophy, to Korean appliance. This is to associate contemporary Leadership Theory with Chosun Confucianism in order to discover the Korean Leadership Prototype, and seek the possibility of applying it for modern usage. The essay uses two analysis models. The tools used for the methodology consists of the personal characteristics of the leader as one axis and ruling out the roles in order to develop the discussion as the other axis. First axis is the process of the leader setting the identity and strengthening the ability to successfully deploy his/her leadership. The second axis is comprised of four specific fields where the leadership is deployed. The four sectors are Self Sector, Relationship Sector, Team Sector and Community Sector. Core values of each sector have been set up and specific competences have been presented. In the Self Sector, $zh{\grave{i}}x{\bar{i}}n$(治心) and $ch{\acute{i}}j{\grave{i}}ng$(持敬) have been set as core values and $l{\grave{i}}zh{\grave{i}}$(立志) and $sh{\acute{i}}x{\bar{i}}n$(實心) as their competences. In the Relationship Sector and Team Sector, circumstances(時宜) and $sh{\acute{i}}sh{\grave{i}}g{\bar{e}}ngzh{\bar{a}}ng$(實事更張) were set as core values, accordingly. Lastly for the Community sector, the core value, 'Ideal Leader and the Visions of and Ideal Community', was conceptualized as '$m{\grave{ui}}m{\acute{i}}nzh{\grave{i}}zh{\grave{i}}$(牧民至治)'. The leadership is then expanded from the Self Sector to the final stage through its processes. Through this research, it can be found out that the Korean Leadership Model is not rigid to just cover a specific point in time or situation, but embraces many contemporary leadership concepts, thus having the characteristics of a comprehensive leadership theory.