• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.3
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• pp.23-29
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• 2002

A wall-frame type structural system has been widely used to make full use of a limited land in large cities to satisfy the several functional requirement in one building. However, this type of hybrid structure brought some problems due to the vertical discontinuity of a structural system. The response of a wall-frame type structural system having a deep transfer girder was observed. An arch system was introduced to replace the deep transfer girder. The adequacy of an arch system was observed for the various boundary conditions of a system. The proposed system was compared to a general transfer girder system by applying both gravity load and lateral load. It was observed that an arch system fairly distributes the stress without concentrating stress at a certain location of a system differently from the current transfer girder system. The moment decrement effect of a column can also be obtained by eliminating the large mass of a transfer girder. Also it was investigated that an arch system is more economical and effective than the current transfer girder system.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.6
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• pp.55-66
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• 2011

The purpose of this study was to develop an efficient process in the design and construction of a 1:5 scale 10-story R.C. apartment building model for an earthquake simulation test. The reduction ratio of the specimen was determined by the size ($5m{\times}5m$) and pay load (600kN) of the available shaking table and the availability of model reinforcements. For efficiency and quality control of the reinforcement work, prefabrication was used. Construction was conducted in two steps, the wall in one step, and another step for the slab, because it was impossible to remove the formwork of a wall if the walls and slabs in a story were constructed in one step. The slip form construction method was used repetitively for walls. The formwork of a wall was made with veneer and acryl plate on each side, so it was possible to check the quality of the concrete placing. To construct this model, it took roughly six months with five full-time research assistants, for a total of 602 man days of labor in construction.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1119-1122
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• 2006

Aeration by using diffusers usually requires approximately 50~90% of the total electricity needed to operate WWTP (WasteWater Treatment Plant)s. Accurate evaluation of the oxygen transfer efficiency for an aeration system, and recommendation of a better alternative may help saving WWTP operational costs. Appropriate techniques and methods to achieve this purpose have not been introduced in Korea. In this study, in-process analysis was performed for a coarse bubble aeration system by the off-gas method to evaluate its applicability in Korea. To accomplish this analysis, an off-gas test, unsteady-state clean water test and steady-state off-gas column test was conducted and comparisons to other aeration systems were made. The ${\alpha}$ and the F estimated from the results of the unsteady-state clean water test and the steady-state off-gas column test were 0.61 and 0.90 respectively in a coarse bubble aeration system. The comparison of P.E tube diffusers laid out single spiral roll and ceramic dome diffusers laid out full floor coverage showed that the oxygen transfer efficiency of the coarse bubble aeration system was less than or similar to other aeration systems. But, airflow rates per unit area were 4~5 times greater than other aeration systems. In regards to the oxygen transfer efficiency for airflow rates per unit area, a retrofit to higher efficiency diffusers was urgently needed. This study showed proved that off-gas methods can apply to evaluate diffuser performances to estimate operating factors and to compare other aeration systems in Korea.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.3
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• pp.261-270
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• 2020

This study reviewed the quality addition rate, calculation, and application criteria needed to identify the possibility of additional medical technologists in the field for new certification and professional manpower to provide a superior laboratory. The six institutions that participated in the study were the size of large hospitals with more than 1,000 beds, with an average of five full-time laboratory physicians (also called clinical pathologists) and an average of 53 medical technologists, with 10.6 per laboratory physician. An analysis of the time required for each activity category of medical technologists revealed decreasing behavior during the analysis. In contrast, the ratio of the comprehensive pre-analysis activities was high due to the strengthening of laboratory operations and quality control. During the analysis, the proportion of biochemistry tests was high, and post-analysis of most of the results was performed. Hence, improving the quality of sample testing requires significant time, and appropriate personnel are required. In conclusion, the recruitment of medical technologists is also a key component to improving the sample quality, and corresponding personnel regulations are necessary.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.677-685
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• 2015

In a will to subdue the brittleness as well as the low tensile and flexural strengths of ordinary concrete, researches are being actively watched worldwide on steel fiber-reinforced Ultra High Performance Concrete (UHPC) obtained by admixing steel fibers in ultra high strength concrete. For the purpose of maximizing advantage of UHPC, this study removes the upper flange of the steel girder to apply an inverted T-shape girder for the formation of the composite beam. This paper intends to evaluate the behavior of the shear connectors and the flexural characteristics of the composite beam made of the inverted T-shape girder and UHPC slab using 16 specimens considering the compressive strength of concrete, the mixing ratio of steel fiber, the spacing of shear connectors and the thickness of the slab as variables. In view of the test results, it seemed that the appropriate stud spacing should range between 100 mm and 2 or 4 times the thickness of the slab. Moreover, the relative displacement observed in the specimens showed that ductile behavior was secured to a certain extent with reference to the criteria for ductile behavior suggested in Eurocode-4. The specimens with large stud spacing exhibited larger values than given by the design formula and revealed that the shear connectors developed larger ultimate strength than predicted owing to the action of UHPC and steel after non-composite behavior. Besides, the specimens with narrow stud spacing failed suddenly through compression at the upper chord of UHPC before reaching the full capacity of the shear connectors.

• Journal of Broadcast Engineering
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• v.18 no.2
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• pp.271-282
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• 2013

Recently, ITU-T/VCEG and ISO/IEC MPEG have started a new joint standardization activity on video coding, called High Efficiency Video Coding (HEVC). This new standard gives significant improvement in terms of picture quality for high resolution video. The main challenge in this upcoming standard is the time complexity. In this paper we have focused on CU splitting algorithm. We have proposed a novel algorithm which can terminate the CU splitting process early based on the RD cost of the parent and current level and the motion vector value of the current CU. Experimental result shows that our proposed algorithm gives on average more than about 10% decrement in time over ECU [8] with on average 1.78% of BD loss on the original.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.53.2-53.2
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• 2010

지금까지 능동 구동 디스플레이의 TFT backplane에 사용하고 있는 채널 물질로는 수소화된 비정질 실리콘(a-Si:H)과 저온 폴리실리콘(low temperature poly-Si)이 대표적이다. 수소화된 비정질 실리콘은 TFT-LCD 제조에 주로 사용되는 물질로 제조 공정이 비교적 간단하고 안정적이며, 생산 비용이 낮고, 소자 간 특성이 균일하여 대면적 디스플레이 제조에 유리하다. 그러나 a-Si:H TFT의 이동도(mobility)가 1 cm2/Vs이하로 낮아 Full HD 이상의 대화면, 고해상도, 고속 동작을 요구하는 UD(ultra definition)급 디스플레이를 개발하는데 있어 한계 상황에 다다르고 있다. 또한 광 누설 전류(photo leakage current)의 발생을 억제하기 위해서 화소의 개구율(aperture ratio)을 감소시켜야하므로 패널의 투과율이 저하되고, 게이트 전극에 지속적으로 바이어스를 인가 시 TFT의 문턱전압(threshold voltage)이 열화되는 문제점을 가지고 있다. 문제점을 극복하기 위한 대안으로 근래 투명 산화물 반도체(transparent oxide semiconductor)가 많은 관심을 얻고 있다. 투명 산화물 반도체는 3 eV 이상의 높은 밴드갭(band-gap)을 가지고 있어 광 흡수도가 낮아 투명하고, 광 누설 전류의 영향이 작아 화소 설계시 유리하다. 최근 다양한 조성의 산화물 반도체들이 TFT 채널 층으로의 적용을 목적으로 활발하게 연구되고 있으며 ZnO, SnO2, In2O3, IGO(indium-gallium oxide), a-ZTO(amorphous zinc-tin-oxide), a-IZO (amorphous indium-zinc oxide), a-IGZO(amorphous indium-galliumzinc oxide) 등이 그 예이다. 이들은 상온 또는 $200^{\circ}C$ 이하의 낮은 온도에서 PLD(pulsed laser deposition)나 스퍼터링(sputtering)과 같은 물리적 기상 증착법(physical vapor deposition)으로 손쉽게 증착이 가능하다. 특히 이중에서도 a-IGZO는 비정질임에도 불구하고 이동도가 $10\;cm2/V{\cdot}s$ 정도로 a-Si:H에 비해 월등히 높은 이동도를 나타낸다. 이와 같이 a-IGZO는 비정질이 가지는 균일한 특성과 양호한 이동도로 인하여 대화면, 고속, 고화질의 평판 디스플레이용 TFT 제작에 적합하고, 뿐만 아니라 공정 온도가 낮은 장점으로 인해 플렉시블 디스플레이(flexible display)의 backplane 소재로서도 연구되고 있다. 본 실험에서는 rf sputtering을 이용하여 증착한 a-IGZO 박막에 대하여 열처리 조건 변화에 따른 a-IGZO 박막들의 광학적, 전기적 특성변화를 살펴보았고, 이와 더불어 a-IGZO 박막을 TFT에 적용하여 소자의 특성을 분석함으로써, 열처리에 따른 Transfer Curve에서의 우리가 요구하는 Threshold Voltage(Vth)의 변화를 관찰하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.128-132
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• 1983

The water relations parameters such as original osmotic pressure $(\Pi_0)$, osmotic pressure $(\Pi_p)$, at the incipient plasmolysis, the volume of osmotic water $(V_o)$ at the full turgor, the relative water content $(RWC^*)$ at the incipient plasmolysis, the volume of osmotic water$(V_p)$ at the incipient plasmolysis, the volume of symplasmic and apoplastic water$(w_s)$ at the maximum turgor, $V_pV_o, \; V_oW_s, \; W_sD_w, \; V_oF_w$ and the elastic modulus were measured through the pressure chamber (DIK-PC-40 Model) technique with the Williams and Geumgangdaerip soybean cultivar shoots. The original osmotic pressure$(\P $i_{0}$ )$, of the both cultivars shoots were appeared insignificant differences as 8.1 bar and 7.8 bar respectively. The osmotic pressure($\pi$$_{p}$ ) at the incipient plasmolysis was 9.0 bar in Williams and 10.4 bar in Geumgangdaerip. The relative water content(RW $C^{*}$) at the incipient plasmolysis was 86.0 per cent in Geumgangdaerip and 92.6 per cent in Williams. The ratio of volume of osmotic water( $V_{p}$ ) at the incipient plasmolysis to total symplasmic water$(V_o)$ , i.e., $V_p/V_o$ was 83.4 per cent in Geumgangdaerip and 90.4 per cent in Williams. The elastic modulus of Geumgangdaerip shoots showed higher value than Williams$(8.5 $\times$ 10^2bar)$ as $1.6 \times10^5$ bar.r.

• Journal of Distribution Science
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• v.13 no.7
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• pp.53-61
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• 2015

Purpose - This research analyzes overseas expansion support systems for small- and medium-sized enterprises in Germany and Japan. Germany and Japan have developed overseas expansion support policies for such enterprises. The study then explores the implications for Korea and its local governments. Research design, data, and methodology - We did a comparative analysis of Japan and Germany and their support for overseas expansion of small and medium companies. Data were mainly collected from the Ministry of Economy, Trade and Industry (Japan) and the Germany Trade and Invest (Germany) agency through statistics and literature surveys, and analysis studies. Results - First, human resources cultivation and funding support policies, which both Germany and Japan use as part of small- and medium-sized enterprise policies, should be modified to Korean circumstances and to reflect its own small- and medium-sized enterprise support needs. Second, both the German policies that support overseas expansion of small- and medium-sized enterprises and those of Japan's include the philosophy and methods that put an emphasis on these enterprises, despite the fact that there are big differences in the overseas policies in these two countries. Third, German and Japanese governments are embracing the idea that small- and medium-sized enterprises are key to their national economies and implementing policies based on the ratio occupied by these enterprises in the domestic consumption or GDP. In other words, Germany and Japan consider small- and medium-sized enterprises as central to their nation's industry, and assess them as economic industry that should definitely exist for the continued survival of big businesses, and not just as merely supplemental to big business. Fourth, whereas Germany emphasizes support to product exhibition in its overseas expansion support policies, Japan is providing integrated support containing foreign direct investment to small- and medium-sized enterprises. Fifth, there are differences in the overseas expansion support in Germany and Japan in terms of their support to big business. Whereas Germany considers support to big business unnecessary, Japan is implementing active support policies to areas corresponding to big business. Korea will have to benchmark the policies of Germany and Japan, and decide whether or not to give full support to small- and medium-sized enterprises, while excluding areas supporting big business. Conclusions - Based on this analysis of German and Japanese overseas expansion support policies, we need to choose the policies that will engender a solid outcome and derive modified policies for the circumstances of Korea. Additionally, we can use the comparison of the overseas support policies of Japan and Germany to choose small- and medium-sized enterprise overseas expansion support policies for Korea. However, we cannot provide specific overseas support policies by industry. This point will be referenced as a limitation of this study. In future research, we expect that some researchers will take an empirical approach to exploring Korean overseas expansion support through collecting cases of overseas support policies and interviewing policy authorities.

• Journal of the Korea Concrete Institute
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• v.22 no.5
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• pp.641-650
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• 2010

The concrete cracking from the restrained stress caused by the shrinkage may play significant cause of deterioration of concrete structures by allowing the permeation of sulphate and chloride ions which in turn triggers corrosion of steel reinforcement. In particular, the cracking becomes more critical as water binder ratio (W/B) is reduced and concrete strength increases. Therefore, it needs to evaluate correctly the comprehensive shrinkage behavior of concrete with high strength: high-strength concrete (HSC), ultra-highstrength concrete (UHSC). The unrestrained shrinkage tests, however, cannot estimate the net shrinkage effectively which affects cracking after full development of strength and stiffness because it does not consider the degree of restraint, strength development, stress relaxation, and so on. Therefore, in this study, both free and restrained shrinkage tests with variables of W/B (W/B of 30, 25 and 16%) and admixtures (fly ash (FA) and granulated blast-furnace slag (BFS)) for HSC, very-high-strength concrete (VHSC) and UHSC were performed. The test results indicated that the autogenous shrinkage and total shrinkage at drying condition were reduced as W/B increased and FA, BFS were added, and the cracking behavior was suppressed as W/B increased and FA was added.