• 전자공학회논문지 IE
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• v.49 no.1
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• pp.1-6
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• 2012

For the performance improvement of a time-to-digital converter(TDC), a 2-stage high resolution TDC has been designed by using a 2-stage vernier time amplifier(2-S VTA). The two stage vernier time amplifier which has a gain over 64 of the resolution can enhance the resolution of the whole two stage TDC. Because of using a vernier TDC, the structure is not limited to advanced processes for achieving high resolution. The proposed TDC has been designed in a $0.18{\mu}m$ CMOS process and simulated with a 1.8V supply voltage. The entire input range is 512ps, and the full resolution 0.125ps.

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1083-1097
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• 1998

The conventional geographic information systems(GIS) is a software which handles spatial and aspatial information of objects in the real world. The system can not support users time-varying information because it manipulates their snapshot data in the spatial database. Also even though it supports time-varying information, it is very limited and hs many difficulties in presenting and processing queries. This paper therefore describes an integrated spatiotemporal data model using loosely-coupled approach which is extended a time dimension for the previous spatial database and which handles time-varying historical information of spatial objects. Conclusionally this paper not only designed a data structure for spatiotemporal database, but also implemented spatial comparison operations varying over time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.489-498
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• 2018

This study was conducted to investigate the effect of walking exercise with blood flow restriction (BFR) on insulin resistance, adipokines and gut hormones in middle aged obese women. Eleven obese women (BMI > 25kg/m2; body fat > 30%) wore pneumatic pressure belts at both femurs and performed walking exercise consisting of walking for 2 min and resting for 1min twice per day, 3 days/wk for 4 weeks. Insulin significantly increased after exercise (p<0.05), while glucose increased slightly, but not significantly. Additionally, HOMA-IR decreased significantly after exercise (p<0.05), while adiponectin and visfatin increased, but not significantly. Finally, ghrelin (p<0.05) and GLP-1 (p<0.05) increased significantly after exercise. These results suggest that walking exercise with blood flow restriction for 4 weeks improves insulin resistance, adipokines, and gut hormones in obese middle-aged women. Therefore, high intensity walking exercise with blood flow restriction for short periods of time has more positive effects on prevention and treatment of obesity-related metabolic diseases.

• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.41-49
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• 1985

Bacillus sphaericus was mutagenized with UV light irradiation and dimethyl sulfate. Thirty-five conditional lethal temperature-sensitive(ts) mutants were isolated at the nonpermissive temperature of $42^{\circ}C$ and classified into three groups by their growth characteristics on the nutrient broth, peptone glucose yeast extract agar and mineral salts agar. First was the lethal ts group, 24 mutants, which did not grow at the nonpermissive temperature, the second, 9 mutants, was the less growth is group whose growth was restricted to one-half, and the third, 2 mutants, was the cold lethal ts group whose growth was restricted at the permissive temperature($25^{\circ}C$and $30^{\circ}C$)

• The Journal of Fisheries Business Administration
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• v.29 no.1
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• pp.139-159
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• 1998

본 연구는 미국 오레곤주의 수산업 특성을 개괄적으로 살펴본 것이다. 먼저, 오레곤의 상업적 수산업을 역사적으로 살펴보면 2가지 주요한 계기가 있음을 알 수 있다. 첫째는 자급자족 차원에서의 연어생산을 수출품으로 변화시킨 연어통조림 생산기술의 발전이고, 둘째는 현대식 트롤어업이 도입된 점이다. 오레곤에서 주로 사용되는 어구ㆍ어법은 트롤, 채낚기, 연승, 통발, 형망 등이며, 생산어종은 연어, 게, 새우, 참치, 대구 등이다. 1995년 오레곤은 약 2억 4천 파운드의 수산물을 생산하여 미국 연안주중에서 6위를 차지하고 있고, 생산금액에서는 12위를 기록하였다. 한편, 양식업은 아직 성행하지 않아 그 생산품종 및 생산량은 미미한 실정이다. 그 주된 이유 중의 하나는 양식시설을 하기 위해서는 여러 관계기관의 허가를 필요로 하는 등 행정상의 절차가 복잡하기 때문이다. 오레곤의 수산자원관리는 우리나라에 비해 암계의 어획금지, 통발 등 정치어구ㆍ어법에 대한 인망일수의 제한, 조개류의 판매가능시간의 제한 등 몇가지 특징을 들 수 있다. 오레곤의 수산업관리제도(연안으로부터 3마일 이내)를 살펴보면, 아직 TAG제도를 도입하지 않고 있으며 생산요소역입제한방식이 채택되고 있다. 즉, 상업적으로 허용된 어종을 어획하려는 어업자는 등록절차를 필히 거쳐야 어업행위를 할 수 있으며, 등록수를 제한할 필요가 있는 특정한 어업(연어, 새우, 가리비 등)에 대해서는 행정관청으로부터 허가를 얻고 어업행위를 해야 한다. 즉, 허가어업은 등록어업보다 더욱 제한적인 어업행위를 말하며, 허가권에 대해서는 자유로운 매매양도가 허용되어 있다. 수산물의 마케팅시스템에 대해서는 우리나라에 지배적인 형태인 경매제도가 도입되어 있지 않다. 즉, 모든 수산물은 개인적인 거래계약에 의해서 유통된다. 다만 마케팅경로에 참여하고 있는 모든 구성원은 일정한 등록절차를 마쳐야 하며, 주내에서 거래되는 수산물의 일관된 통제나 관리를 위해 관계기관에 거래량을 필히 신고해야 한다. 우리나라의 중도매인은 주로 생산지의 수협(또는 내륙지 도매법인)과 도매상의 사이에 존재하나 오레곤의 중도매인은 마케팅경로 어디에든 존재하고 있다.

• KSBB Journal
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• v.5 no.1
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• pp.9-17
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• 1990

The growth and fermentation profiles of Clostridium acetobutylicum KCTC 1037 were examined in batch and continuous modes with pH variation and phosphate limitation. Clostridium acetobutylicum KCTC 10 37 grew better at pH 4.5 than at pH 5.5 or 6.5. Acetate and butyrate were produced at pH 5.5, whereas culture at pH 4.5 produced acetone and butanol. Solvent production was increased by the phosphate limitation in a batch culture, but in a phosphate-limited continuous culture for 400 hours steady-state solventogenesis was not observed. The induction and maintenance of solventogenesis presumably require not only acidic condition or phosphate limitation but also favourable bioenergetic condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.10C
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• pp.1032-1041
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• 2007

The global navigation satellite system (GNSS), which is the core technique for the location based service, adopts the direct sequence/spread spectrum (DS/SS) as its modulation method. The success of a DS/SS system depends on the synchronization between the received and locally generated pseudo noise (PN) signals. As a step in the synchronization process, the tacking scheme performs fine adjustment to bring the phase difference between the two PN signals to zero. The most widely used tracking scheme is the delay locked loop with early minus late discriminator (EL-DLL). In the ideal case, the EL-DLL is the best estimator among various DLL. However, in the band-limited multipath environment, the EL-DLL has tracking bias. In this paper, the timing offset range of correlation function is divided into advanced offset range (AOR) and delayed offset range (DOR) centering around the correct synchronization time point. The tracking bias results from the following two reasons: symmetry distortion between correlation values in AOR and DOR, and mismatch between the time point corresponding to the maximum correlation value and the synchronization time point. The former and latter are named as the type I and type II tracking bias, respectively. In this paper, when the receiver has finite bandwidth in the presence of multipath signals, it is shown that the type II tracking bias becomes a more dominant error factor than the type I tracking bias, and the correlation values in AOR are not almost changed. Exploiting these characteristics, we propose a novel tracking bias mitigation scheme and demonstrate that the tracking accuracy of the proposed scheme is higher than that of the conventional scheme, both in the presence and absence of noise.

• The Journal of Korean society of community based occupational therapy
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• v.2 no.2
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• pp.1-13
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• 2012

Objective : The purpose of this study was to understand the game world experience and peer interaction of students with disabilities in the community. Method : In this study, Giorgi's phenomenological method was used to understand the game world experience and peer interaction of two students with disabilities in the community. The data collection about the situation and the context of the subjects was conducted over three times of interviews, until no new data. Meaning units through the four steps for Giorgi's scientific phenomenology were analyzed in the context of the overall data. Result : Two students with disabilities in the community had to spend time at home with physical limitation and alienation, and their leisure activities was mainly using the computer and television. Restrictions of leisure activities wad the cause of difficulties of social accessibility, and they need the correct thinking and self-control in the use of the time. Due to the game for fun, they have no interact with peers. On the other hand, most of conversation about the game were with families. Conclusion : Students with disabilities had a physical and psychological difficulties were feeling pleasure through the game. They need the correct thinking and self-control in the use of the time, and need an alternative solution for a reckless game use.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.2
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• pp.19-29
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• 2011

Due to the development of web technologies and the increasing use of smart devices such as smart phone, in recent various web services are widely used in many application fields. In this environment, the topic of supporting personalized and intelligent web services have been actively researched, and an analysis technique on a web-click stream generated from web usage logs is one of the essential techniques related to the topic. In this paper, for efficient analyzing a web-click stream of sequences, a sequential pattern mining technique is proposed, which satisfies the basic requirements for data stream processing and finds a refined mining result. For this purpose, a concept of interesting sequential patterns with a time-interval constraint is defined, which uses not on1y the order of items in a sequential pattern but also their generation times. In addition, A mining method to find the interesting sequential patterns efficiently over a data stream such as a web-click stream is proposed. The proposed method can be effectively used to various computing application fields such as E-commerce, bio-informatics, and USN environments, which generate data as a form of data streams.

• Journal of Venture Innovation
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• v.5 no.3
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• pp.57-70
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• 2022

In modern industrial capitalism, the relationship between the provision of work and the receipt of wages has become an important principle governing society. According to the labor contract, the wages provided by entrusting the right to dispose of one's labor to the employer are directly compensated, and human life should be guaranteed and reproduced with proper rest. The establishment of labor relations under free contracts represents a problem in protecting workers, and accordingly, the maximum of working hours is set as a minimum right for workers, and the standard for minimum rest is set and assigned. The reduction of working hours is very important in terms of the quality of life of workers, but it is also an important issue in efficient corporate activities. As of 2020, Korea has 1,908 hours of annual working hours, the third lowest among OECD 37 countries in the happiness index surveyed by the Sustainable Development Solution Network(SDSN), an agency under the United Nations. Accordingly, the necessity of reducing working hours has been recognized, and the maximum working hours per week has been limited to 52 hours since 2018. In this situation, various working hours are legally excluded as a way to maintain the company's value-added creation and meet the diverse needs of workers, and Korea's Labor Standards Act restricts flexible working hours within three months, flexible working hours exceeding three months, selective working hours, and extended working hours. However, in the discussion on the application of the revised flexible working hours system in 2021 and the expansion of the settlement unit period recently discussed, there is a problem with the flexible working hours system, which needs to be improved. Therefore, this paper aims to examine the problems of the flexible working hours system and improvement measures. The flexible working hours system is a system that does not violate working hours even if the legal working hours are exceeded on a specific day or week according to a predetermined standard, and does not have to pay additional wages for excessive overtime work. It is mainly useful as a form of shift work in manufacturing, sales service, continuous business or electricity, gas, water, and transportation for long-term operations. It is also used as a way to shorten working hours, such as expanding holidays through short working days. However, if the settlement unit period is expanded, it is disadvantageous to workers as the additional wages that workers can receive will not be received. Therefore, First, in order to expand the settlement unit period currently under discussion, additional wages should be paid for the period expanded from the current standard. Second, it is necessary to improve the application of the flexible working hours system to individual workers to have sufficient consultation with individual workers in a written agreement with the worker representative, Third, clarify the allowable time for extended work during the settlement unit period, and Fourth, limit the daily working hours or apply to continuous rest. In addition, since the written agreement of the worker representative is an important issue in the application of the flexible working hours system, it is necessary to secure the representation of the worker representative.