• 수산해양기술연구
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• 제46권4호
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• pp.392-405
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• 2010

The population of small yellow croaker, Larimichthys polyactis, in the Yellow and East China Seas has decreased significantly since the mid 1970s. Several management measures have been introduced to conserve it, but population size remains low. To rebuild this population, it is now necessary to consider more effective management methods based on the stock assessment. To determine long-term population changes, fishery and biological data collected over 34 years (1969-2002) were analysed. Yearly fish length compositions were analysed for the time periods 1968 through 1970, 1978 through 1982, and 1993 through 2002; and catch data was available from 1969 to 2002. Annual population sizes were calculated based on length composition, the relationship between total length and body weight, and total landings. Analyses showed that since the 1970s, average size of harvested fish decreased; the proportion of less mature fish (smaller than the 50% maturity length, 19cm) in catches has increased and the estimated biomass has decreased significantly. Consequently, the main management recommendation is that juvenile fish need to be better protected to allow the rebuilding of resources to a more sustainable population level. This will require fish size limit, permissible mesh size, and closed area and season regulations.

• Asian Pacific Journal of Cancer Prevention
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• 제13권2호
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• pp.443-446
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• 2012

Purpose: Telomeres play a key role in the maintenance of chromosome integrity and stability, and telomere shortening is involved in initiation and progression of malignancies. The aim of this study was to determine whether telomere length is associated with the colorectal carcinoma. Patients and methods: A total of 148 colorectal cancer (CRC) samples and corresponding adjacent non-cancerous tissues were evaluated for telomere length, P53 mutation, and cyclooxygenase-2 (COX-2) mutation detected by fluorescent immunohistochemistry. Telomere length was estimated by real-time PCR. Samples with a T/S>1.0 have an average telomere length greater than that of the standard DNA; samples with a T/S<1.0 have an average telomere length shorter than that of the standard DNA. Results: Telomeres were shorter in CRCs than in adjacent tissues, regardless of tumor stage and grade, site, or genetic alterations (P=0.004). Telomere length in CRCs also had differences with COX-2 status (P=0.004), but did not differ with P53 status (P=0.101), tumor progression (P=0.244), gender (P=0.542), and metastasis (P=0.488). There was no clear trend between T/S optimal cut-off values (<1 or > 1) and colorectal tumor progression, metastasis, gender, P53 and COX-2 status. Conclusion: These findings suggesting that telomere shortening is associated with colorectal carcinogenesis but does not differ with tumor progression, gender, and metastasis.

• 한국정밀공학회지
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• 제19권9호
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• pp.142-150
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• 2002

This study describes a method of finding an optimal path of a soccer robot by using a concentric circle method with different radii of rotation. Comparing with conventional algorithms which try to find the shortest path length, the variable concentric circle method find the shortest moving time. The radius fur the shortest moving time for a given ball location depends on the relative location between a shooting robot and a ball. Practically it is difficult to find an analytical solution due to many unknowns. Assuming a radius of rotation within a possible range, total path moving time can be calculated by adding the times needed for straight path and circular path. Among these times the shortest time is obtained. In this paper, a graphical solution is presented such that the game ground is divided into 3 regions with a minimum, medium, and maximum radius of rotation.

• 대한전기학회논문지:전력기술부문A
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• 제51권5호
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• pp.238-246
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• 2002

Utilities are trying to install the equipment of high quality to avoid deterioration of supply reliability. In addition, many sectionalizing switches which can decrease the total outage value for a fault are installed for the same reason. Therefore, utilities are interested in stun dards and criteria for installing switches to optimize the total cost on distribution systems. The affect of sectionalizing switches installed on distribution feeder is gradually decreased because the failure rate on distribution feeder is decreased. Also the automation for distribution systems is widely applied for the efficient operation. Therefore, the renewal for installation standards of sectionalizing switches Is required to reflect the current operation situation. The variable data is used to consider the KEPCO's real situation of distribution feeder as follows; the feeder capacity, connecting rate, feeder length, failure rate of distribution feeder, the failure rate of switches, perception time of feeder fault, the restoration time for a faulted section, the transfer time to other feeders, and the switching time. In this study, We propose equations which can determine the number of sectionalizing switches for minimizing the outage and switch installation cost.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.70-73
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• 2002

Utilities are trying to install the equipment of high quality to avoid deterioration of supply reliability. In addition, many sectionalizing switches which can decrease the total outage value for a fault are installed for the same reason. Therefore, utilities are interested in standards and criteria for installing switches to optimize the total cost on distribution systems. The affect of sectionalizing switches installed on distribution feeder is gradually decreased because the failure rate on distribution feeder is decreased. Also the automation for distribution systems is widely applied for the efficient operation. Therefore, the renewal for installation standards of sectionalizing switches is required to reflect the current operation situation. The variable data is used to consider the KEPCO's real situation of distribution feeder as follows; the feeder capacity, connecting rate, feeder length, failure rate of distribution feeder, the failure rate of switches, perception time of feeder fault, the restoration time for a faulted section, the transfer time to other feeders, and the switching time. In this study, We propose equations which can determine the number of sectionalizing switches for minimizing the outage and switch installation cost.

• 한국수산과학회지
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• 제19권4호
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• pp.375-379
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• 1986

남해 서부해역에 위치한 여자만에서 바닥식으로 양성한 피조개, Anadara broughtonii에 관한 성장과 폐사에 관해 1982년 8월부터 6개월간 조사한 결과는 다음과 같다. 1. 종패의 각장이 $20{\sim}30mm$, 평균 25mm되는 것을 1982년 3월 $1m^2$당 평균 30개체를 양성장 바닥에 살포하였는데, 약 6개월 후에 각장은 평균 48.0mm로 성장하였으며 익년 2월에는 평균 60.6mm가 되었다. 2. 패각과 각부중량의 증가는 고수온기에 빨랐으며 시간이 지남에 따라 패각의 한쪽 형태는 타원형에서 원형으로 변하고 육질중량의 증가는 패각 성장의 증가 속도보다 빨랐다. 3. 성장은 순조로와 피조개의 양성장으로 적합하지만 폐사가 많았다. 종패 살포 1개월 후 약 $30\%$가 폐사하고 폐사는 계속되어 수확시에는 생잔율이 약 $10\%$에 지나지 않았다. 폐사의 주 원인은 해적생물인 불가사리(Asterias spp.) 때문이었다.

• 한국양식학회지
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• 제1권1호
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• pp.1-11
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• 1988

넙치의 종묘생산에 관한 기초적 자료를 얻기 위하여 넙치 자어 및 치어에 Artemia nauplii와 배합사료를 먹이로 했을 때, 이들의 섭식과 소화에 대해서 조사한 결과는 다음과 같다. 평균전장 11.38$\~$17.08 mm인 자어 및 치어의 포식에 이르는 시간은 수온 $24\~25^{\circ}C$에서 $45\~55$ 분이었으며, 포식량은 1마리당 236$\~$375개체였으나, 수온 $19\~21^{\circ}C$에서는 거의 1시간이 소요되었다. 소화관내에 섭식된 먹이중 장에서의 비율이 가장 높았던 때는 수온 $24\~25^{\circ}C$에서 먹이를 공급한 후 35분이었고, $19\~21^{\circ}C$에서는 45분이었다. 이때의 백분율은 $24.8\%$였다. 평균전장 4.39$\~$10.64 cm인 치어의 배합사료 포식양은 1마리당 0.04$\~$0.46g이고, 이때 섭식률과 일간성장률은 각각 $5.80\~4.01\%$, $1.13\~0.69\%$였다. 경과시간별 소화관 중량지수의 변화는 포식후 24시간 동안은 급격히 낮아졌으나, 그 이후는 완만하여 공복에 이르는 시간은 48시간으로 추정되었다.

• 대한기계학회논문집B
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• 제24권11호
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• pp.1549-1554
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• 2000

A new method to determine the total heat exchange factor was proposed for the prediction of billet temperature in a reheating furnace. This method employed the squared of the difference between measured and predicted temperatures as an objective function. The real billet temperature in a walking beam type reheating furnace with 19.75m of its effective length was directly measured by thermocouples. The present method was validated by showing that the predicted billet temperature was in a good agreement with the measured one.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.67-73
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• 2007

Anhui Province, with a total north-south length of 570km and an east-west width of 450km and a total area of 139.6 thousand km2, accounts for 1.45% of China's total area. The landform and land feature of Anhui Province is diverse, and generally it can be divided into 5 natural regions: (1) Huaibei Plain; (2) Jianghuai Hillocks; (3) Dabie Mountains in the West of Anhui Province; (4) Yanjiang Plain, (5) Mountain Area of southern Anhui Province. Anhui Province is located in the transitional zone of warm and humid zone and subtropical zone, and its mean annual precipitation is 800-1800mm. The province, which has diverse climate, multiple land forms and many rivers and lakes, passes three basins (Huaihe River, Yangtze River and Xin'an River) and has large differences in the time distribution and regional distribution of water resource. Therefore, the development and usage conditions of the water resource in different regions are different.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.73-76
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• 1997

A low loss x-cut LiNbO$_3$ optical waveguide was fabricated by Ti in-diffusion and the guided-mode properties and total insertion loss of pigtailing with polarization maintaining fiber(PMF) were investigated and measured at optical wavelength 15507. For formaing the waveguide, the parameters of diffusion Ti thickness, waveguide line-width, length, diffusion temperature, time and atmosphere were set 1400$\AA$, 8${\mu}{\textrm}{m}$, 3.3cm, 105$0^{\circ}C$, 8 hours and wet bubbled oxygen, respectively. and then After the polishing and pigtailing, it showed that total insertion loss was -4.1dB for TM mode, -5.5dB for TE mode, and mode size, that is, horizontal/vertical sizes were 13.87/18${\mu}{\textrm}{m}$ for TM mode, 9.61${\mu}{\textrm}{m}$/6.5${\mu}{\textrm}{m}$ for TE mode.