• Journal of Powder Materials
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• v.18 no.6
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• pp.482-487
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• 2011

Alloy 617, Ni-22Cr-12Co-9Mo base oxide dispersion strengthened alloy was fabricated by using mechanical alloying, hot isostatic pressing and hot rolling. Uniaxial tensile tests were performed at room temperature and at $700^{\circ}C$. Compared with the conventional Alloy 617, ODS alloy showed much higher yield strength and tensile strength, but lower elongation. Fracture surfaces of the tensile tested specimens were investigated in order to find out the mechanism of fracture mode at each test temperature. Grain adjustment during tensile deformation was analyzed by electron backscattered diffraction mapping, inverse pole figures and TEM observation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.7
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• pp.1453-1460
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• 2002

Creep-fatigue crack growth models have been proposed employing $(C_t)_{avg}$ as a crack tip parameter characterizing the time-dependent crack growth. The basic assumptions made in these previous models were ideal creep reversal conditions such as no creep reversal and complete creep reversal condition. Due to this assumption, the applicability of the models was limited since they did not consider partial creep reversal condition which is usually observed in many engineering metals at high temperature. In this paper the creep reversal parameter, Temperature;$C_R$, which was defined by Grover, is critically evaluated to quantity the extent of partial creep reversal at the crack tip. This approach does not rely on any simplifying assumptions regarding the extent of the amount of creep reversal during the unloading part of a trapezoidal fatigue cycles. It is shown that the $(C_t)_{avg}$ value calculated for 9Cr steel agrees well with the experimentally measured one. It is argued that the extent of improvement is not significant when the result is compared with that of the conventional model which has an assumption of full creep reversal behavior.

• BMB Reports
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• v.39 no.5
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• pp.537-545
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• 2006

CMTM/CKLFSF is a novel family of proteins linking chemokines and TM4SF. In humans, these proteins are encoded by nine genes, CKLF and CMTM1-8/CKLFSF1-8. Here we report the characteristics and expression profile of CMTM3/CKLFSF3. Human CMTM3/CKLFSF3 has a high sequence identity among various species and similar characteristics as its mouse and rat homologues. Established by results both of RT-PCR and Quantitative Real-time PCR, the gene is highly transcribed in testis, leukocytes and spleen. For further verification, we generated a polyclonal antibody against human CMTM3/CKLFSF3 and found that the protein is highly expressed in the testis and some cells of PBMCs. Therefore, CMTM3/CKLFSF3 is an evolutionarily conserved gene that may have important roles in the male reproductive system and immune system. Further studies are necessary to validate its functions in the two systems.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.224-227
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• 2006

닭고기를 표면에 미생물 수준을 달리하여, Polyethylene으로 포장함에 따라 저장 5일의 $10^2\;CFU/cm^2$ 처리구에서 TBARS 값이 0.071, $10^3\;CFW/cm^2$, 0.084, $10^4\;CFU/cm^2$, 0.093 mgMA/kg로 계속 증가하는 경향을 나타내었다. 육색에서 명도(L*), 황색도(b*)는 미생물 수준에 따라 일정한 경향을 나타내지 않았다. 미생물 수준에 따른 총 세균수는 저장 3일 $10^2\;CFU/cm^2$ 처리구에서 3.44, $10^3\;CFU/cm^2$, 3.68, $10^4\;CFU/cm^2$, 4.10 log $CFU/cm^2$로 계속 증가하는 경향을 나타내었다. 이러한 경향은 저장 5일에서도 비슷한 경향을 나타내었다. E. coli의 변화는 저장 3일에 $10^2\;CFU/cm^2$ 처리구에서 1.44, $10^3\;CFU/cm^2$, 2.12, $10^4\;CFU/cm^2$, 2.29 log $CFU/cm^2$로 계속 증가하는 경향을 나타내었고, 저장 5일에서도 저장 3일과 비슷한 경향을 나타내었다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.228-232
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• 2006

닭고기를 표면에 미생물 수준을 달리하여, plastic tray와 wrap으로 포장함에 따라 저장 3일에 TBARS 값이 도체의 미생물 수준이 증가할수록 $10^2\;CFU/cm^2$ 처리구 0.064, $10^3\;CFU/cm^2$, 0.079, $10^4\;CFU/cm^2$, 0.088 mgMA/kg으로 계속 증가하는 경향을 나타내었고 저장 5일에서도 비슷한 경향을 나타내었다. VBN의 변화도 도체 내 미생물 수준이 증가할수록 전체적으로 증가하는 경향을 나타내었다. 육색에서 명도(L*), 황색도(b*)는 미생물 수준에 따라 일정한 경향을 나타내지 않았다. 미생물 수준에 따른 총 세균수는 저장 3일 $10^2\;CFU/cm^2$ 처리구에서 3.34, $10^3\;CFU/cm^2$, 3.67, $10^4\;CFU/cm^2$ 3.77 log $CFU/cm^2$로 도체 미생물 수준이 증가할수록 약간씩 증가하는 경향을 나타내었다. 이러한 경향은 저장 5일에서도 비슷한 경향을 나타내었다. E. coli의 변화는 저장 3일에 $10^2\;CFU/cm^2$ 처리구에서 1.70, $10^3\;CFU/cm^2$, 1.69, $10^4\;CFU/cm^2$ 1.77 log $CFU/cm^2$으로 $10^4\;CFU/cm^2$ 처리구에서 가장 높은 증가율을 나타내었다. 저장 5일에서도 저장 3일과 비슷한 경향을 나타내었다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.2
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• pp.89-98
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• 1985

As a primary step in studying the effects of the netting porosity on the net-shape in the four-seam trawling net, a series of experiments were performed changing the porosity of each panel, with the simplified mo:iel of the bag net made of porous vinyl film and that ma:ie of net webbing. These models were suspended horizontally in circularly flowing water, with two pairs of susp~nding threais to four points of symetry at the border of the bag mouth in place of both wing nets. And then, the section shape of the bag mouth photographed and the tensions on both pairs of suspending threads were measured with two load cells in circularly flowing water. From the results, the auther estimated an experimental equation from the relationship between the porosity of each panel in the bag net and the section shape of the bag mouth, h/w=k (l-Pr_u/lPr_s)

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4269-4292
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• 2014

Currently, increasing numbers of access points (AP) are being deployed in enterprise offices, campuses and municipal downtowns for flexible Internet connectivity, but most of these access points are idle or redundant most of the time, which causes significant energy waste. Therefore, with respect to power conservation, applying energy efficient strategies in WIFI networks is strongly advocated. One feasible method is dynamically managing network resources, particularly APs, by powering devices on or off. However, when an AP is powered on, the device is initialized through a long boot time, during which period clients cannot be associated with it; therefore, the network performance would be greatly impacted. In this paper, based on a global view of an entire WLAN, we propose an AP selection technology, known as Temporary Access Selection (TAS). The criterion of TAS is a fusion metric consisting of two evaluation indexes which are based on throughput and battery life, respectively. TAS is both service and clients' preference specific through balancing the data rate, battery life and packet size. TAS also works well independently in traditional WLANs in which no energy efficient strategy is deployed. Moreover, this paper demonstrates the feasibility and performance of TAS through experiments and simulations with Network Simulator version 3 (NS3).

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.269-273
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• 2004

본 연구는 노계육의 화염처리의 정도에 따른 육질 및 저장 특성의 변화를 구명하고자 수행하였다. 육질특성에서 hardness(경도)는 노계육의 가슴살에서 저장 1일에 화염처리를 하지 않는 처리구에서 4.72kg을 나타냈으며 중처리에서는 4.66kg, 강처리에서는 5.05kg으로 강처리구에서 가장 높게 나타났으나 저장기간이 경과할수록 오히려 강처리구에서 경도의 변화가 가장 크게 떨어져 저장 5일에 1.02kg까지 낮아졌다. 지방산패도(TBA)는 저장 5일에 최대로 증가하였으며 특히 화염처리 수준이 가장 높은 처리구(80PSI)에서 0.21mgMA/kg으로 가장 높은 값을 나타내었다. 단백질산패도(VBN)는 저장 5일에 화염처리하지 않는 처리구에서 4.94mg%를 나타냈고, 중 및 강처리구에서 각각 6.58, 6.57mg%으로 나타나 저장기간이 많을수록 화염처리수준이 증가할수록 값이 증가하는 경향을 나타냈었다. 총미생물 수에서 저장 3일에 화염처리하지 않는 구에서 $4.85Log_{10}\;CFU/cm^2$으로 나타났고, 화염처리 수준이 증가할수록 약간 감소하는 경향을 나타내어 강처리구에서 $4.55Log_{10}CFU/cm^2$수준을 나타냈다. 결과적으로 화염처리 수준이 증가할수록 육질의 경도, 지방산패도 및 단백질 변성도가 증가한 것으로 나타났고, 반면에 총 미생물 수는 저장기간이 경과할수록 낮아지는 것을 알 수 있었다.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.127-148
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• 2009

The objective of this paper is to evaluate of fisheries competitiveness in Korea, China and Japan. A joint research with researchers from Korea, China and Japan from 2007 to 2008 was conducted to analyze competitiveness of each respective fishery industry. An industry's competitiveness means the aggregated and potential abilities of the infrastructure, producers and other operators in the industry. The study improved the Norway-Iceland Model developed by the FCI Team(2005) and applied it to the fisheries of the 3 countries. To compare competitiveness of each fishery from the 3 countries, the study examined 87 items including 64 questions and 23 statistics items. Korea fisheries' competitive advantage over China is in marketing capability. Capabilities of fishing companies and fishing processors are also slightly over Japan's performance. However, Korea holds an absolute disadvantage over China and Japan when it comes to the macroeconomic environments and government support, industrial environments and infrastructure, and production and management. Korea's fishing companies and fishing processors especially are much weaker than those of China. In conclusion, Korea needs strategies to advance the industry's structure, China needs to expand the industry's base and Japan needs to differentiate the industry.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2001-2003
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• 2005

Various organic acid were used in order to prepare new metalorganic deposition solution for high quality $REBa_2Cu_3O_{7-{\delta}}$ (RE=Y, Eu, Gd) films. Prepared fluorine free MO precursor solution was coated on single crystal (001) $LaAlO_3$ (LAO) by dip coating method. Processing parameters such as oxygen partial pressure, water vapor, ramping rate and pyrolysis temperature etc havebeen controlled in order to make high $J_c$ films with a good epitaxial relationship with substrate. 0.5 micron-thick film was obtained by single coating and no crack appeared after calcination. Oxygen partial pressure was varied in the range of $100{\sim}1,000 ppm$ and conversion heat treatment was carried out at the temperature of $725{\sim}765^{\circ}C$. A critical transition temperature $(T_{c0})$ of 90K and a critical transport current density $(J_c)$ of $>0.5MA/cm^2$ (77K and self-field) were demonstrated for the YBCO film on (001) oriented LAO substrates with a thickness of 0.5 micron. $I_c$ was determined by utilizing a transport measurement. SEM and XRD investigations confirmed that films were grown epitaxially onto the LAO single crystal substrate. It is thought that fluorine free new MOD solutionis promising for high quality REBCO films.