• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.5
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• pp.25-33
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• 2011

This work proposes a skinny-type 10b 50MS/s 0.13um CMOS three-step pipeline ADC for CIS applications. Analog circuits for CIS applications commonly employ a high supply voltage to acquire a sufficiently acceptable dynamic range, while digital circuits use a low supply voltage to minimize power consumption. The proposed ADC converts analog signals in a wide-swing range to low voltage-based digital data using both of the two supply voltages. An op-amp sharing technique employed in residue amplifiers properly controls currents depending on the amplification mode of each pipeline stage, optimizes the performance of op-amps, and improves the power efficiency. In three FLASH ADCs, the number of input stages are reduced in half by the interpolation technique while each comparator consists of only a latch with low kick-back noise based on pull-down switches to separate the input nodes and output nodes. Reference circuits achieve a required settling time only with on-chip low-power drivers and digital correction logic has two kinds of level shifter depending on signal-voltage levels to be processed. The prototype ADC in a 0.13um CMOS to support 0.35um thick-gate-oxide transistors demonstrates the measured DNL and INL within 0.42LSB and 1.19LSB, respectively. The ADC shows a maximum SNDR of 55.4dB and a maximum SFDR of 68.7dB at 50MS/s, respectively. The ADC with an active die area of 0.53$mm^2$ consumes 15.6mW at 50MS/s with an analog voltage of 2.0V and two digital voltages of 2.8V ($=D_H$) and 1.2V ($=D_L$).

• The Korean Journal of Air & Space Law and Policy
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• v.5
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• pp.101-118
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• 1993

Generally there is no law and liability system which applies particulary to commercial space ventures. There are several international treaties and national statutes which deal with space ventures, but their impact on the liability of commercial space ventures has not been significant. Every state law in the United States will impose both tort and contract liability on those responsible for injuries or losses caused by defective products or by services performed negligently. As with the providers of other products and services, those who participate in commercial space ventures have exposure to liability in both tort and contract which is limited to the extent of the resulting damage The manufacturer of a small and cheap component which caused a satellite to fail to reach orbit or to operate nominally has the same exposure to liability as the provider of launch vehicle or the manufacturer of satellite into which the component was incorporaded. Considering the enormity of losses which may result from launch failure or satellite failure, those participated in commercial space ventures will do their best to limit their exposure to liability by contract to the extent permitted by law. In most states of the United States, contracts which limit or disclaim the liability are enforceable with respect to claims for losses or damage to property if they are drafted in compliance with the requirements of the applicable law. In California an attempt to disclaim the liability for one's own negligence will be enforceable only if the contract states explicitly that the parties intend to have the disclaimer apply to negligence claims. Most state laws of the United States will refuse to enforce contracts which attempt to disclaim the liability for gross negligence on public policy grounds. However, the public policy which favoured disclaiming the liability as to gross negligence for providers of launch services was pronounced by the United States Congress in the 1988 Amendments to the 1984 Commercial Space Launch Act. To extend the disclaimer of liability to remote purchasers, the contract of resale should state expressly that the disclaimer applies for the benefit of all contractors and subcontractors who participated in producing the product. This situation may occur when the purchaser of a satellite which has failed to reach orbit has not contracted directly with the provider of launch services. Contracts for launch services usually contain cross-waiver of liability clauses by which each participant in the launch agrees to be responsible for it's own loss and to waive any claims which it may have against other participants. The crosswaiver of liability clause may apply to the participants in the launch who are parties to the launch services agreement, but not apply to their subcontractors. The role of insurance in responding to many risks has been critical in assisting commercial space ventures grow. Today traditional property and liability insurance, such as pre-launch, launch and in-orbit insurance and third party liability insurance, have become mandatory parts of most space projects. The manufacture and pre-launch insurance covers direct physical loss or damage to the satellite, its apogee kick moter and including its related launch equipment from commencement of loading operations at the manufacture's plant until lift off. The launch and early orbit insurance covers the satellite for physical loss or damage from attachment of risk through to commissioning and for some period of initial operation between 180 days and 12 months after launch. The in-orbit insurance covers physical loss of or damage to the satellite occuring during or caused by an event during the policy period. The third party liability insurance covers the satellite owner' s liability exposure at the launch site and liability arising out of the launch and operation in orbit. In conclusion, the liability in commercial space ventures extends to any organization which participates in providing products and services used in the venture. Accordingly, it is essential for any organization participating in commercial space ventures to contractually disclaim its liability to the extent permitted by law. To achieve the effective disclaimers, it is necessary to determine the applicable law and to understand the requirements of the law which will govern the terms of the contract. A great deal of funds have been used in R&D for commercial space ventures to increase reliability, safety and success. However, the historical reliability of launches and success for commercial space ventures have proved to be slightly lower than we would have wished for. Space insurance has played an important role in reducing the high risks present in commercial space ventures.

• Korean Journal of Ecology and Environment
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• v.38 no.4 s.114
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• pp.482-493
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• 2005

The objective of this research was to evaluate an sampling effect of fish species and individual number on sampling techniques of electrofishing and conventional capture methods of cast net and kick net in 38 stream sites sampled during June - September, 2005. For the study, sampling gears were categorized as three types of electrofishing method (EM), conventional sampling technique (CM), and the combined technique (CT) of the electrofishing and the conventional method to compare statistical differences. Major differences of species composition between the CM and EM method were found in some benthic species of Misgurnus mizolepis and Iksookimia koreensis along with lithophilic species of Pungtungia herzi. These species were predominated in the EM rather than the CM, indicating that conventional sampling can underestimate the abundance of benthic or lithophilic species. In contrast ,individual number of typical water column species such as Zacco platypus and Zacco temmincki were more sampled by the CM, so that these fish populations were community overestimated. Also, t-tests on the types of sampling gear from various watersheds of Chogang Stream, Yugu Stream, Daejeon Stream, and Gap Stream showed that total individual numbers and species number in each stream were significantly (t values = 2.806-6.896, p values<0.05, n = 5-14) greater in the CT than the CM. Similar statistical significance (p<1.001, n = (10-24) on sampling seasons were observed during the monsoon and postmonsoon. These results indicate that if the electrofishing is not added to the conventional gears, the abundance of fish population and community can be underestimated and some benthic or lithophilic species may be excluded from the analysis, resulting in overall errors including sampling, fish fauna, and final judgement of community abundance. Overall our results strongly suggest that new application of electrofishing method along with the conventional sampling gears reduce sampling bias on underestimation of the real fish populations and communities.

• Korean Journal of Ichthyology
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• v.31 no.4
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• pp.222-234
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• 2019

Fish community characteristics and habitat aspects of endangered species, Pseudopungtungia tenuicorpa and Acheilognathus signifer were investigated in the Hwayangcheon Stream of Songnisan National Park, a tributary of the Hangang River, Korea from April to October 2018. During this period, there were 29 species of 8 families collected from 11 survey stations using kick nets, cast nets long bag set nets. The dominant and subdominant species were Zacco koreanus (38.81%) and Rhynchocypris oxycephalus (16.64%), respectively. The next most abundant species were Z. platypus (14.28%), Pungtungia herzi (6.92%), Hemibarbus longirostris (4.52%), Pseudogobio esocinus (3.51%), A. signifer (2.31%) and P. tenuicorpa (1.90%). Among the fish collected, 18 species (62.1%) were Korean endemic species. Endangered species were A. signifer, P. tenuicorpa and Gobiobotia brevibarba. From upstream to downstream, the dominance index has gradually decreased, but number of species and individuals, diversity and evenness has gradually increased. Also, river health (index of biological integrity) is assessed as good (St. 1~8) and very good (St. 9~11). Fish communities were divided into four sections by the similarity index based on species and their numbers, i.e., upper section (St. 1~2, 4~5), upper-middle section (St. 3, 6), middle section (St. 7~9) and lower section (St. 10~11). Endangered species, Pseudopungtungia tenuicorpa inhabited in mostly lower section (St. 10~11) with rock and boulder bottoms, and age groups in April estimated from total length indicated that the 44~61 mm group is 1 year old, the 66~81 mm group is 2 years old, the 88~99 mm group is 3 years old, and the 104~107 mm group is more than 4 years old. Also, endangered species, A. signifer inhabited in middle-lower section (St. 7~11) with boulder and cobble bottoms and slow velocity, which the place inhabited by water plants. Meanwhile, their age structure in April estimated from total length indicated that the 30~43 mm group is 1 year old, the 48~58 mm group is 2 years old, the 62~77 mm group is 3 years old, and the 84~100 mm group is more than 4 years old. The sex ratio of female (47) to male (42) was 1 : 0.89.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.266-279
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• 2019

We investigated the characteristics of fish communities and habitat status of endangered species Rhodeus pseudosericeus in Heuk Stream, a tributary of the Han River, from April to October 2018. During this period, we collected 47 species of 14 families from 10 survey stations using kick nets, cast nets, and long bag set nets. The dominant and subdominant species were Zacco platypus (37.6%) and Z. koreanus (13.8%), respectively. The next most abundant species were Squalidus gracilis majimae (11.1%), Pungtungia herzi (7.7%), Rhodeus pseudosericeus (5.0%), Microphysogobio yaluensis (4.3%), and Hemibarbus longirostris (3.0%). Among the fish collected, 19 species (40.4%) were Korean endemic species. Endangered species were R. pseudosericeus and Acheilognathus signifer while exotic species were Micropterus salmoides and Oncorhynchus mykiss, and land-locked species were Plecoglossus altivelis and Rhinogobius brunneus. The community analysis showed that the dominance and evenness indexes were mostly low and that the diversity and richness indexes were high. Moreover, the river health (index of biological integrity) was mostly excllent (1 site is good, 9 sites are very good). R. pseudosericeus inhabited widely from St. 3 to St. 9 in Heuk Stream, and its population size was large. Age groups for R. pseudosericeus estimated by the frequency distribution of total length in spawning season (April) indicated the 32~45 mm group as 1-year old, the 46~59 mm group as 2-years old, 60~69 mm group as 3-years old, and the 70~89 mm group as 4-years or older. Total length range of male and female was similar, and the sex ratio of female (426) to male (394) was 1 : 0.95. A. signifer, which had been released in Heuk Stream, inhabited from St. 4 to St. 5, but its population size was small. Lastly, this paper discusses a conservation plan for fish in Heuk Stream.

• (The)Study of the Eastern Classic
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• no.49
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• pp.161-185
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• 2012

This thesis reorganized the life of Mrs. Yun who was a noble woman in the middle of the Joseon period with main material of Seopo, Kim, Man Joong(1637-1692)'s "Seonbijungkyungbuinhaengjang(先?貞敬夫人行狀)" and considered yeosa(女師)'s image of noble woman embodied by her son. Although women who were remarkable in premodern period nurtured their son well and they became excellent, it's easy that the life of their mother can be hidden by sons' shadow. Luckily, materials of Mrs. Yun were kept by her descendants, so people could analogize how she could endure difficulties and how she educate her children. In a word, the life of Mrs. Yun can be yeosa(女師)'s life. She was born as a only daughter of the best ancestry in the period and grown to be a considerable woman with strong will and discipline under the strict training of her grandmother, Junghye Ongju. And then, she married Gwangsan Kimmun, the best literature house of Joseon period, but her husband, Kim, Ik Kyum was died by unexampled difficulty, Byungjahoran. During the tribulation, Mrs. Yun was in charge of not only parents supporting but also two sons' education excellently. She educated not only her children but also grandchildren and nephews around her, so she had extraordinary passion and sincerity for the education. As the result, she enjoyed a glory that two sons and grandchildren became on daejehak. Mrs. Yun was living with thrift and saving continuously regardless of her circumstances. When her granddaughter became inkyungwanghoo who is a wife of sookjong, she didn't kick her common habit and trained strictly the mind of family members who could be easily in disorder. In spite of the richness, he obeyed manners and showed thrift and saving continuously and thoroughly. When there was a crisis in her family, the first son, Kim, Man Ki was died and the second son, Kim, Man Joong and grandson went into exile during the continuous political upheaval. But, she supported her house, obeyed the rules and promised the future. At that time, she continuously encouraged grandchildren and the eldest grandsons of the head family to study without any stop for themselves in spite of the difficulties. Mrs. Yun pursued truly valuable life. She considered that the life which didn't get praised by other people wasn't valid although he or she lived a pleasant life in luck and richness. Mrs. Yun was a true teacher yeosa (女師) who placed a true value on the life enduring hardship and poorness without fear and becoming an example of other people.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1309-1321
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• 2023

This study was conducted by dividing L-arginine intake group (n=14) and placebo group (n=14) to investigate the effect of L-arginine intake on athletic performance, lactate, lactate dehydrogenase, and ammonia of men's college Taekwondo Kyorugi players during 8-week of intensive winter training. The L-arginine intake group consumed a total of 3 g, including 1 g for breakfast, 1 g for lunch, and 1 g for dinner, and the placebo group consumed maltodextrin in the same way. The 8-week winter training program was conducted at 70-90%HRR (heart rate reserve). Two-way repeated measures ANOVA was used for the interaction between the L-arginine intake group and the placebo group of the measured data, paired t-test was used for the difference between the periods within the group, and the difference between groups was analyzed using independent t-test. As a result, there was an interaction between groups in the average number of kicks among the performance ability through the TAAA (Taekwondo-specific aerobic anaerobic agility) test , and the main effect between groups was shown (p<.05). In addition, there was an interaction between groups and time in the kick fatigue index (p<.05). In lactate, the time-interaction were shown (p<.05) and interaction effects and inter-time main effects were observed in lactate dehydrogenase (LDH)(p<.05). In the case of ammonia, the interaction effect between the group and time was shown (p<.05). These results show that L-arginine intake can play a positive role in quickly synthesizing nitric oxide in blood vessels and expanding blood vessels to quickly remove fatigue-causing substances in the body for athletes who are easily exposed to fatigue after high-intensity training for male college Taekwondo Kyorugi players. Therefore, it is recommended to take L-arginine as a way to improve the performance of high-intensity elite Taekwondo Kyorugi players and recover from fatigue.