• Journal of Embryo Transfer
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• v.6 no.2
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• pp.1-17
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• 1991

It is widely recognized that the embryonic or fetal loss after breeding is common in the cattle and that it is an important factor affecting reproductive efficiency. The causes of this loss have been subject of extensive researches and the results indicate that the embryonic mortality may he primary factor responsible for low pregnancy rates in non-embryo transfer bovine populations as well as embryo transfer programs. However, it's causes are still not clearly understood. The embryonic mortality or pregnancy rate has been influenced by various embryonic and maternal effects related to genetic and environmental factors. The timing and extent of embryonic mortality vanes greatly according to authors and estimating methods, because it is difficult to make direct measurements. The major important factors that may influence the embryonic losses or pregnancy rates after embryo transfer can be summeirized. 1.When an embryo is transferred to unmated recipients, the contralateral transfer to corpus luteum results in a lower survival rate than ipsilateral deposition. When the embryos are transferred for the production of twin calves, their survivals and twin pregnancies have quite inconsistent according to the transfer methods either to the unmated-synchronized or already mated recipients and more works are needed to accurrately clarify the previous results. 2.Although embryos can be cultured in vitro some hours without the great declines in pregnancy rates, the rates differ markedly among culture times and media but may be improved by co-transfer systems. 3.Embryo developmental stages and quality grades clearly affect the survival rate following freezing and the pregnancy rate after transfer and the selection of embryos without chromosome abnormalities and of high fertile semen may also be considered to increase the pregnancy rates. 4.Many researches have attempted to relate the plasma progesterone levels to pregnancy rates and others have done either direct progesterone supplementation or luteal stimulation by hCG treatment in order to increase the pregnancy rates. However, these effects on pregnancy rates are inconsistent and also contradictory. 5.The asynchrony between donors or embryos and recipients may he a major cause of embryo death and low pregnancy rate and the sensitivity to uterine asynchyony differs in according to the quality and stages of embryos. 6.The extremes of poor or over nutrition during early pregnancy in the recipients are detrimental to the survival of embryos and the good body condition is required to prevent a reduejion of pregnancy rates. The uterine pathogens in embryonic mortality or fertility have been questioned but the infection of C.pyogenes and Campylobacter fetus is still important pathogens. 7.The heat stress during early pregnancy may reduce conceptus weight and possibly increase the embryonic mortality.

• Journal of computational fluids engineering
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• v.3 no.1
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• pp.82-88
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• 1998

As a par of a project related to the development of the design algorithm of a compact heat exchanger for the application of the electronic home appliances, the effect of the discreteness of the airflow boundary generated on the cooling fin surface on the heat transfer and pressure drop characteristics of the heat exchanger was studied numerically. In general, there are two critical design parameters seriously considered in the design of the heat exchanger; heat transfer rate(Q) and pressure drop coefficient(C/sub p/). Even though the higher heat transfer rate with lower pressure drop characteristics is required in a design of the heat exchanger, it is not an easy job to satisfy both conditions at the same time because these two parameters are phenomenally inversely proportional. To control the boundary layer thickness and its length along the streamline, the surface of the flat fin was modified to accelerate the heat transfer rate on the fin surface. To understand the effect of the discreted fin size(S/sub w/) and its location(S/sub h/) on the performance of the heat exchanger in the airflow field, the flat fin was modified as shown in Fig. 1. From this study, it was found that the smaller and more number of slits on the fin surface showed the higher energy diffusion rate. It means that the discreteness of the boundary layer is quite important on the heat transfer rate of the heat exchanger. On the other hand, if the fin surface configuration is very complex than needed, higher static pressure drop occurs than required in a system and it may be a reason of the induced aerodynamic noise in the heat exchanger.

• Journal of the Korean Regional Science Association
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• v.15 no.3
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• pp.69-86
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• 1999

One of the conclusions from the researches of the last 40 years on the relationship between technological development and economic growth is that technology is an essential factor in economic growth. A majority of firms in developing countries, including Korea, are small to medium sized, so technology transfers is an alternative to developing in those technologies. Such firms prefer technology transfers over self-development because of time and money savings. This paper analyzes the types and processes of technology transfers and suggests a direction and tasks to establish a technomart through an examination of domestic and foreign case studies. Laws, organizations and institutional aspects which are related to establishing technomart are also discussed.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.64-64
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• 2003

• The Journal of Pediatrics of Korean Medicine
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• v.17 no.2
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• pp.37-53
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• 2003

Objective : To find risk factor and symptoms for transferred newborn from postpartum care center Method : We performed a follow-up study using medical record. Subjects comprised 188 neonates(include 4 twins) and 184 women in childbed who were hospitalized in oriental postpartum care center from January, 1, 2002 to December, 31, 2002. Result: Transferred newborn was total 24, N.V.D. 17, C.S. 7, male and female were 12 separately. The symptom of transfer was fever(16), diarrhea(4), jaundice(3), convulsion(1) Transferred number and rate was male 12(10.7%), female 12(15.8%). In delivery method, total normal vaginal delivery(N.V.D.) was 136 and transferred 17(12.5%), total cesarean section(C.S.) was 52 and transferred 7(13.5%). Transferred rank was N.V.D. female(17.9%). C.S. male(15.6%), C.S. female(10%), N.V.D.(8.6%). Of the 188 neonates. immature infants were 2 and transferred 1(50%), term infants were 184, transferred 23(12.5%), post-term infants were 2 and transferred none(0%). In age of women in childbed, transferred ratio was 15.4%(over 35), 15.2%(25-29), 10.5%(30-34). In fever,. C.S. infants were more transferred than N.V.D. and male infant had a tendency to transfer in later period of hospitalization and female in early period. It seems that transfer was related to abortion. In diarrhea, all was N.V.D. and their diagnosis was rotavirus. The average age of women in childbed was yonger(28.5). In jaundice, all was 1st, and average birth weight was lighter(3153g). The average age of women in childbed was older(30). In convulsion, birth weight was lighter(3153g), and age of women in childbed was older(30). Conclusion : There's any relation with sex and delivery method, birth weight and mother's age in transfer. But we cannot find any statistically significance. Further prospective studies are needed to find risk factors in transfer.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.1
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• pp.165-175
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• 2012

Recently, accumulation of technology, transfer, absorption, and commercialization is being significantly recognized as a key factor for sustainable growth of the 21st century global economy. The government established "Technology Transfer and Commercialization Promotion Act" In order that the technology developed at public research institutions can be transferred to the private sector and commercialized; the technology developed in the private sector can be traded and commercialized. Also, the Article 14 of "Technology Transfer and Commercialization Promotion Act" is concerning technology transfer agents' registration, promotion, and support: it introduced the special status system of technology transfer agents and the government registers, manages, and supervises it. In most developed countries, the technology transfer agency is transferred to the private sector and it is referred as a technology transfer agent or technology broker. In the domestic market, despite the introduction of the above special status system and the building a various organization and transfer medium system for boosting the market's revitalization, some problems occurred; because the registration system of a technology transfer agent and legal basis and system about its following-up control fall short. For example, recently technology transfer-related performance exemption has brought the activation of technology transfer agent's registration, but there was the limit of selecting the expert above a certain level. Therefore, some countermeasures for this are urgent, In addition, through a compulsory training completion system before the technology trade agent registration is prepared, a short period of curriculum was not sufficient to provide applicants various specialized knowledge. In this research, it is considered about the reform of technology transfer agent through its comparative study in China and Korea. Some improvements are suggested for expanding the market of technology transfer commercialization, assuring the agents' service and strengthening the competitiveness.

• The Research Journal of the Costume Culture
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• v.14 no.2
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• pp.206-219
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• 2006

The purpose of this study was to design the ideal student uniform for improving the university image which is related to ideal PR (Public Relations). The results of this study were as follows: Firstly, as for the matter of UIP(University Identity Program), the uniform must transfer the university image. Using the UIP symbol color, the uniform is harmonious with university environment, and should be properly expressed visual image of the university. Secondly, the symbol which expressed the tradition and the spirit of the university was the very important factor to transfer its unique university identity and image of the university in the uniform design. The symbol which comes from the character or textile prints of the university symbolic flower or animals should transfer the consistent and unique design of university identity. Thirdly, the uniform has to be designed considering of the fashion trend as well as the essential factors for the uniform, considering such as functional, beautiful, symbolic aspects. In designing the uniform, fashion trend should be considered to combine the students and the uniform users to be one. As mentioned above, the uniform design which is suggested on this study should be helpful for the improvement of the university status and the reinforcement of the university PR.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.4
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• pp.5-13
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• 2004

This study explains the effects of lubricant and surface treatment on the life of hot forging dies. The thermal load and thermal softening, that occur when there is contact between the hotter billet and the cooler dies in hot forging, cause wear, thermal cracking and fatigue, and plastic deformation. Because the cooling effect and low friction are essential to the long life of dies, the proper selection of lubricant and surface treatment is very important in hot forging process. The two main factors that decide friction and heat transfer conditions are lubricant and surface treatment, which are directly related to friction factor and surface heat transfer coefficient. Experiments were performed for obtaining the friction factors and the surface heat transfer coefficients in different lubricants and surface treatments. For lubrication, oil-base and water-base graphite lubricants were used, and ion-nitride and carbon-nitride were used as surface treatment conditions. The methods for estimating die service life that are suggested in this study were applied to a finisher die during the hot forging of an automobile part. The new techniques developed in this study for estimating die service life can be used to develop more feasible ways to improve die service life in the hot forging process.

• Archives of Craniofacial Surgery
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• v.24 no.4
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• pp.159-166
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• 2023

Background: Free tissue transfer is the preferred method of reconstructing head and neck defects, with a success rate of approximately 95%. Although flap failure is uncommon, it has a major impact on patient morbidity and diminishes quality of life, making it is important to investigate the causes of flap failure. Methods: This retrospective chart review analyzed patients who underwent free tissue transfer during head and neck reconstruction at a single institution between 2016 and 2021. Results: During the study period, 58 patients underwent 60 free flap procedures. Revision surgery was needed in 14 patients. Subsequent free flap surgery was performed in one patient, and three free flaps (5%) could not be salvaged. Cardiovascular disease was significantly associated with flap failure, and venous congestion (thrombosis) was the most common reason for revision surgery. Conclusion: Cardiovascular disease clearly emerged as a factor related to the failure of free flap surgery, and this issue warrants particular attention in patients for whom free tissue transfer is planned.

• Journal of the Korean Society of Visualization
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• v.22 no.1
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• pp.79-84
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• 2024

As microchips' degree of integration is getting higher, its cooling problem becomes important more than ever. One of the promising methods is using fractal microchannel heat sink by mimicking nature's Murray networks. However, most of the related works have been progressed only by numerical analysis. Perhaps such lack of direct experimental studies is due to the technical difficulty of the temperature and heat flux measurement in complex geometric channels. Here, we demonstrate the direct visualization of in situ temperature profile in a fractal microchannel heat sink. By using the temperature-sensitive fluorescent dye and a transparent Polydimethylsiloxane window, we can map temperature profiles in silicon-based fractal heat sinks with various fractal scale factors (a=1.5-3.5). Then, heat transfer rates and pressure drops under a fixed flow rate were estimated to optimize hydrodynamic and thermal characteristics. Through this experiment, we found out that the optimal factor is a=1.75, given that the differences in heat transfer among the devices are marginal when compared to the variances in pumping power. This work is expected to contribute to the development of high-performance, high-efficiency thermal management systems required in various industrial fields.