• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.465-469
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• 2000

This paper describes a single-chip full-custom implementation of pipelined adaptive decision-feedback equalizer (PADFE) using a 0.25-${\mu}{\textrm}{m}$ CMOS technology for wide-band wireless digital communication systems. To enhance the throughput rate of ADFE, two pipeline stage are inserted into the critical path of the ADFE by using delayed least-mean-square (DLMS) algorithm Redundant binary (RB) arithmetic is applied to all the data processing of the PADFE including filter taps and coefficient update blocks. When compared with conventional methods based on two's complement arithmetic, the proposed approach reduces arithmetic complexity, as well as results in a very simple complex-valued filter structure, thus suitable for VLSI implementation. The design parameters including pipeline stage, filter tap, coefficient and internal bit-width and equalization performance such as bit error rate (BER) and convergence speed are analyzed by algorithm-level simulation using COSSAP. The singl-chip PADFE contains about 205,000 transistors on an area of about 1.96$\times$1.35-$\textrm{mm}^2$. Simulation results show that it can safely operate with 200-MHz clock frequency at 2.5-V supply, and its estimated power dissipation is about 890-mW.

• Imaging Science in Dentistry
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• v.30 no.3
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• pp.189-198
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• 2000

Purpose: The study was aimed to detect the induction of apoptosis, cell cycle arrest and calcified nodule formation after irradiation on primarily cultured osteoblasts. Materials and Methods: Using rat calvarial osteoblasts, the effects of irradiation on apoptosis, cell cycle arrest, and calcified nodule formation were studied. The single irradiation of 10 and 20 Gy was done with 5.38 Gy/min dose rate using the l37Cs cell irradiator at 4th and 14th day of culture. Apoptosis induction and cell cycle arrest were assayed by the flowcytometry at 1, 2, 3, and 4 days after irradiation. The formation of calcified nodules was observed by alizarin red staining at 1, 3, 10, 14 days after irradiation at 4th day of culture, and at 1, 4, 5 days after irradiation at 14th day of culture. Results: Apoptosis was not induced by 10 or 20 Gy independent of irradiation and culture period. Irradiation did not induced G1 arrest in post-irradiated ostedblasts. After irradiation at 4th-day of culture, G2 arrest was induced but it was not statistically significant after irradiation at 14th-day of culture. In the case of irradiated cells at 4th day of culture, calcified nodules were not formed and at 14th-day of culture after irradiation, calcified nodule formation did not affected. Conclusion: Taken together, these results suggest that irradiation at the dose of 10-20 Gy would not affect apoptosis induction of osteoblasts. Cell cycle and calcified nodule formation were influenced by the level of differentiation of osteblasts.

• Journal of Yeungnam Medical Science
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• v.17 no.2
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• pp.129-136
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• 2000

Background and Purpose: This study was undertaken to compare the sensitivity of the Repetitive Nerve Stimulation Test (RNST) between the upper and lower extremity muscles in myasthenia gravis(MG) patients. Material and Methods: The study population consisted of 20 normal persons(control group) and 10 MG patients(MG group). Using Stalberg's method. RNST was systemically performed in orbicularis oculi muscle. upper extremity muscles(flexor carpi ulnaris. abductor digiti quinti), and lower extremity muscles(tibialis anterior. extensor digitorum brevis. vastus medialis). Results: There were statistical differences of decremental response($mean{\pm}SD$) in orbicularis oculi and upper extremity muscles between the control and MG groups(p<0.05 or p<0.01). However, there was no statistical difference of decremental response($mean{\pm}SD$) to RNST in lower extremity muscles between the control and MG groups. There were highersensitivity in orbicularis oculi and upper extremity muscles than lower extremity muscles. Although positive reponse were detected in the lower extremity muscles, the positive response rates of lower extremity muscles were lower than o.oculi and upper extremity muscles. Conclusions: When the response rates of RNST in facial and upper extremity muscles are normal, may not be required RNST in lower extremity muscles.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.247-255
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• 2003

80년대 초 GIS의 개념이 국내에 도입된 후, 1988년 대구광역시를 필두로 지자체의 GIS 구축이 시작되어 국가에서는 GIS 구축의 체계적인 관리의 필요성에 따라 1995년 제1차 국가GIS 기본계획을 수립하고, 2000년 ‘국가지리정보체계의 구축 및 활용 등에 관한 법률’을 제정, 공포하여 각 지자체의 실정에 맞는 GIS 기본계획을 수립하도록 유도하고 있다. 그러나, 바람직한 지자체 GIS 기본계획 작성의 표준이 제시되지 않아 지자체 GIS 기본계획이 개인의 안목이나 타 지자체의 내용을 참조로 만들어져 형식적이고 획일적인 결과물이 산출되고 있다. 그리하여 기존에 수립된 지자체 GIS 기본계획이 일부의 지자체를 제외하고는 해당 지자체의 GIS 구축 사업에 활용되지 못하고 책장속의 책으로 존재하고 있다. 따라서, 본 논문의 목적은 지자체 GIS 기본계획 표준안을 제시하여 향후 해당 지자체에서 GIS 기본계획을 수립할 때, 구성적인 측면의 틀을 제공하여 일정수준을 만족할 수 있는 지자체 GIS 기본계획의 수립을 지원하고자 한다. 지자체 GIS 기본계획 표준(안)을 도출하기 위해서 정보화전략계획과 해외 관련 연구, 국가GIS 기본계획의 검토를 통하여 지자체 GIS 기본계획의 구성요소를 도출하고, 기존지자체 GIS 기본계획의 목차를 중심으로 분석하여, 문제점을 도출하고, 그에 따른 시사점을 제시하여 지자체 GIS 기본계획 표준(안)의 기반이 되도록 하였다. 제안된 지자체 GIS 기본계획 표준(안)은 향후 각 지자체의 활용가치가 높은 GIS 기본 계획의 수립에 도움이 될 수 있도록 하며, 나아가서는 수립된 지자체 GIS 기본계획이 지자체의 성공적인 GIS 구축을 유도하는 가이드의 역할을 수행할 것으로 기대된다.가 있다. 본 연구의 결과를 통해 지방자치단체 GIS 기본계획에 있어 조직 측면의 장기적 비전의 제시가 가능하며 이를 통해 보다 성숙된 GIS 사업의 추진과 효율적인 시스템의 운영이 가능할 것이다.. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplifie

• The Korean Journal of Nuclear Medicine
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• v.34 no.2
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• pp.144-153
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• 2000

Purpose: The purpose of this study was to evaluate the relationship between radiation-induced activation of DNA repair genes and radiation induced apoptosis in A431 cell line. Materials and Methods: Five and 25 Gys of gamma radiation were given to A431 cells by a Cs-137 cell irradiator. Apoptosis was evaluated by flow cytometry using annexin V-fluorescein isothiocyanate and propidium iodide staining. The expression of DNA repair genes was evaluated by both Northern and Western blot analyses. Results: The number of apoptotic cells increased with the increased radiation dose. It increased most significantly at 12 hours after irradiation. Expression of p53, p21, and hRAD50 reached the highest level at 12 hours after 5 Gy irradiation. In response to 25 Gy irradiation, hRAD50 and p21 were expressed maximally at 12 hours, but p53 and GADD45 genes showed the highest expression level after 12 hours. Conclusion: Induction of apoptosis and DNA repair by ionizing radiation were closely correlated. The peak time of inducing apoptosis and DNA repair was 12 hours in this study model. hRAD50, a recently discovered DNA repair gene, was also associated with radiation-induced apoptosis.

• Journal of Korean Academy of Nursing
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• v.30 no.2
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• pp.452-462
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• 2000

There are currently 214 orphanages in Korea which house approximately 13,873 orphans aged between 3 and 18; this accounts for about 0.12% of all children in the same age range. Some have lost their parents, but most have come after their parents divorced or broke up. This means majority of the children in Child Care Centers have parents. Traditional virtue of obedience to parents (Hyo) was regarded as one of the highest value in Korea. Also the interaction between parents and their children was regarded as basic human nature that parents look after, both physically and spiritually, their children until they become one of the matured social member. Raised without having a chance to realize their filial duty and not having been cared for by their parents, most orphans feel that they lack something in their lives when compared with friends. In the end, they live their lives longing for their parents and go through mental discord about their parents. This paper is focused on understanding orphans' experience and views on parents. I approached the issue by applying van Manen's Hermeneutic Phenomenological Approach. The interviews, along with other reference material were phenomenologically reflected to draw essential themes as follows; 1. Orphans of pre-school age hazily long for parents without having any practical image of their parents. 2. They occasionally dream meeting their parents with image that can only last in their dreams, and this continues up through middle school. 3. At the age of elementary school, they crave the image of parents as they see their friends with their parents. 4. They start to despise their parents for having abandoned them when they reach puberty. 5. Meanwhile, as their vague image of parents fade away, they attempt to give up their thoughts toward their parents. 6. Highteens start to think in terms of fate. 7. They don't long for their parents anymore as they used to, but still wishes to meet them at least once. However, they don't want to start any kind of a relationship with them. 8. They fear that they will also fail in raising families of their own, and making their children orphans too, just like their parents have. They simply don't want to follow their footsteps. 9. Thinking that they were abandoned by their parents, they are reluctant to believe other people.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.701-711
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• 2000

To provide the baseline information for establishing community based nutritional service system in the context of health promotion, we conducted nutrition survey for 196 adults (male ; 99, female ; 97) in Kyungpook area. Individual food intake was measured by 24-hour recall method, and then diet quality was evaluated by Index of Nutritional Quality (INQ) and Mean Adequacy Ratio (MAR). Average dietary intake of Ca and Vit A of total subjects were lower than Korean Recommended Dietary Allowances (Ca; 83% of RDA, Vit A; 77% of RDA). On the whole, mean nutrients intake of male subjects were higher than that of female subjects. It also appeared that overall nutrients intake of younger women (20~29 yr) were lower than that of other age group. When we evaluated the nutrients intake of the subjects by INQ, Vit C (=2.39) showed the highest score. Ca (=0.89) and Vit A (=0.84) were revealed to be concerned nutrients in both quantity and quality. There was almost no difference in MAR between men and women (Men ; 0.88, Women ; 0.86). MAR showed significantrly positive correlation with age (p<0.05), meal frequency (p<0.001) and negative correlation with education level (p<0.01) in women, whereas no statistically significant relationship among these variables was observed in men. Age and meal frequency showed significantly positive correlation with most nutrients intakes among women. In conclusion, nutrition education strategies for sound food choice and regular meals need to be developed to improve the nutritional adequacy of female adults in the 20's.

• Journal of Technology Innovation
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• v.25 no.3
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• pp.115-154
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• 2017

This article offers a review of the major literature about sectoral innovation studies of Korea and its implications over the past 30 years. The literature on the sectoral innovation studies in Korea has focused on analysing successful technological catch-up from an evolutionary perspective and most of research has centered on the issues about entry strategies, learning mechanisms. Recently "Emerging economies" like Korea in the 2000s face major challenges as they make a transition from (a) a phase of economic development characterised by 'catching up' with the global technological frontier, involving technological "imitation", to (b) a phase of continuing development based on the development of new knowledge for globally leading (post catch-up) product and process innovation. This paper reviews those bodies of literature of patterns of sectoral innovation, technological capability accumulation and catch-up process, catch-up innovation and institutions, and patterns of growth dynamics. Finally, given the importance of sectoral innovation studies, we suggest that industrial upgrading, transition towards leadership, dark side of catch-up issues are needed for future research directions.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.136-143
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• 2002

Emission of methane and nitrous oxide affected by nitrogen fertilizer materials were measured simultaneously in rice paddy fields under flooding and intermittent irrigation in 2000. Studies focused on mitigating $CH_4$ emission from rice paddy fields are summarized and the possibilities and limits applied to world's rice cultivation are discussed. The mitigation options are water management, soil amendments, organic matter management, different tillage, rotation, and cultivar selection. Altering water management, in particular promoting midseason aeration by short-term drainage, is one of the most promising strategies, although these practices may be limited to the rice paddy fields where the irrigation system is well prepared. The test site was divided into two water managements: a continuously flooded plot which was maintained flooded by constant irrigation from May to September, and an intermittently drained plot in which short-term (20days) draining practices were performed one times during the flooding period. By total emission of GHGs converted by global warming potential (GWP), flooding plots were higher 170$\sim$208% than interimittent irrigation plots. For emission of GHGs in fertilizer materials, it was high in the order of Swine slurry>Urea+Rice straw>Urea>LCU. Basing on GHGs emission of urea fertilization under flooding as baseline GWP of urea fertilization and Latex-coated urea under intermittent irrigation showed lower GHGs emission by 41.4% and 55.8 respectively. In this case fertilizer use efficiency (kg unhulled rice/ of applied N) were 18.2$\sim$20.2 and 18.7$\sim$19.0 and 9.3 and 5.8$\sim$6.6 for Swine slurry and LCU and Urea+Rice straw and Urea in the continuously flooded and intermittently drained plot.

• Analytical Science and Technology
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• v.13 no.6
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• pp.766-774
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• 2000

The major and trace constituents of Mongolian chromite were analyzed by ICP-AES. The dissolution procedures, mixed acid ($HClO_4+H_3PO_4$) digestion and fusion with $Na_2O_2$ flux, have been studied to dissolve the chromite. The optimum dissolution method was found to be a fusion with $Na_2O_2$ flux. The effect of large amount of Na on major and trace constituents was examined when these elements were determined by ICP-AES. There was no effect on major elements at a concentration of Na 250 mg/L solution. The emission intensity of trace constituents containing Na 1,250 mg/L decreased to 1.0-5.2% according to elements and wavelengths. The result of this method was compared with that of neutron activation analysis (NAA) to confirm the accuracy of this procedure. The results between two methods were in a good agreement within less than 5% for $Al_2O_3$, $Cr_2O_3$, MgO and -20 to 8% for Co, Mn, V, Zn, respectively.