• Journal of Power Electronics
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• v.16 no.5
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• pp.1763-1772
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• 2016

To reduce system complexity and implementation costs, fully-controlled H-bridge (FHB) modules and diode H-bridge PFC (DHB) modules are cascaded to form a hybrid cascaded H-bridge rectifier (HCHR). In this paper, the advantages of such a HCHR over other cascaded rectifiers are analyzed depending on the numbers of FHB modules and DHB modules. Therefore, to assign proper numbers to these two kinds of modules for the HCHR, a configuration determination method is investigated under balanced and imbalanced loads. Three principles are also presented to guide the configuration determination for the HCHR. In addition, the constraints for selecting the step-up ratio and filter inductance are derived based on a phasor diagram analysis. The proposed configuration determination method is validated by simulations under three different conditions in the PSIM environment. Finally, experiments are carried out on a scaled-down prototype where the configuration can be easily adjusted. The feasibility of the proposed theory is then verified by experimental results.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.685-690
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• 2007

The deoxysugar biosynthetic gene cluster of Sch 47554/Sch 47555 was cloned from Streptomyces sp. SCC-2136. One of the ORFs, schS6, appeared to encode glucose-1-phosphate thymidylyltransferase, which converts dTTP and glucose-1-phosphate to TDP-D-glucose and pyrophosphate. The dTDP-D-glucose is a key metabolite in prokaryotics as a precursor for a large number of modified deoxysugars, and these deoxysugars are a maj or part of various antibiotics, ranging from glycosides to macrolides. SchS6 was expressed in E. coli vector pSCHS6 and the expressed protein was purified to apparent homogeneity by ammonium sulfate precipitation and Ni-NTA affinity column chromatography. The specific activity of the purified enzyme increased 4.7-fold with 17.5% recovery. It migrated as a single band on SDS-PAGE with an apparent molecular mass of 56kDa. The purified protein showed glucose-1-phosphate thymidylyltransferase activity, catalyzing a reversible bimolecular group transfer reaction. In the forward reaction, the highest activity was obtained with combination of dTTP and ${\alpha}-D-glucose-1-phosphate$, and only 12% of that activity was obtained with the substrates $UTP/{\alpha}-D-glucose-1-phosphate$. In the opposite direction, the purified protein was highly specific for dTDP-D-glucose and pyrophosphate.

• Advances in pediatric surgery
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• v.6 no.1
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• pp.45-49
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• 2000

Henoch-Sch$\ddot{o}$nlein purpura is a systemic vasculitis of unknown etiology that is probably related to an autoimmune phenomenon. Henoch-Sch$\ddot{o}$nlein purpura is characterized by a purpuric rash, arthralgia, nephritis, and gastrointestinal manifestations. We reviewed 169 children hospitalized with a diagnosis of Henoch-Sch$\ddot{o}$nlein purpura between 1989 and 1998. One-hundred thirty-nine (82.2 %) had gastrointestinal findings including abdominal pain, nausea, vomiting and gastrointestinal bleeding. Surgical consultations were obtained for ten children, and laparotomy was performed in five. Three children suspected of having appendicitis underwent appendectomy. None had appendicitis. One child thought to have been intestinal strangulation was found to have hemorrhagic edema of the proximal jejunum and of the distal ileum. Another child underwent resection for an hemorrhagic infarct of the distal ileum. A high index of suspicion of this disease entity in the differential diagnosis of abdominal pain in children can avoid unnecessary laparotomy in most cases. However, life-threatening gastrointestinal complications may occur in low percentage of cases. Prompt recognition and adequate radiologic evaluation of the abdominal manifestation of this entity is necessary for early surgical intervention.

• Journal of the Korean housing association
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• v.15 no.1
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• pp.163-174
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• 2004

The purpose of this study was 1) to analyze the attitudes about Senior Congregate Housing(SCH) among 4 urban areas, 2) to propose the various model for SCH which should be provided to satisfy the demand. Same opinions among 4 urban areas were ; 1) Whom were willing to move into SCH for later life, most of them were in early 50s. Most of the respondents desired to be serviced community alarm system, preferred one-room style, size of 11∼15 Pyung, and preferred living at suburban area. The multi-family type was preferred when not being healthy and be singled, but if healthy, preferred the type of single detached house. And they preferred the home ownership, highly valued of heating control system, health care and leisure programs. Thus for the future SCH, it should be designed all facilities were equipped with sports facilities, sauna and leisure programs. The findings indicated that the high rates of supporting with professional management for 24 hours by turn. But different opinions among 4 urban areas were; 2) Willingness live in SCH for later life had little difference in level of income, education, property. Especially, residents of Seoul Metropolitan area and Busan did not want to open their own common facilities to the public.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.30-37
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• 2018

Unlike an AC system, a DC system does not cause problems with synchronization, stability, reactive power, system losses, and cost. However, more research is still required for the application of DC Systems. This paper proposes a stable black-start strategy for a stand-alone DC micro-grid, which consists of an energy storage system, photovoltaic generator, wind-turbine generator, diesel generator, and DC loads. The proposed method is very important for avoiding inrush current and transient overvoltage in the power system equipment during restoration after a blackout. PSCAD/EMTDC software was used to simulate, analyze, and verify the method, which was found to be stable and applicable for a stand-alone DC micro-grid.

• Journal of the Korean Home Economics Association
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• v.42 no.7
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• pp.1-17
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• 2004

This study was conducted to determine the influence of socio-economic status of potential consumers on the types of senior congregate housing(SCH) among 4 urban areas(Seoul Metropolitan area, Busan, Gwangaju, and Daejun). This study was part or a research series to develop SCH which meets the korean situation. The Questionnaire used for the final analysis involved 1006 people and SPSS Windows program was used for statistical analysis. The opinion about SCH should differ among the 4 urban areas according to Socio-Economic Status(SES). The results of this study were as follows: The opinions on SCH varied in each region according to SES indicating that diverse constructions of senior housing to meet selective needs of the old can create high demand in a construction market. In order to induce active participation of the private sector, the Ministry of Construction and Transportation, rather than the Ministry of Health and Welfare, should be in charge of the development of SCH. This is desirable in the perspective of developing new types of housing as for general housing. In this case, the Ministry of Construction and Transportation should consider geographic locations and environmental factors of each city. Moreover, the successful development of SCH needs an effort to reexamine an appropriate development plan rather than adopting the cases of developed countries without criticism. In terms of policies, the government should provide financial support for building sharing space, give an exception on a measurement rate, assist in the education of supervisors and establish a management system and so on.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8B
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• pp.809-818
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• 2002

In this paper, we propose a fast cell search algorithm keeping compatible with the standard cell search algorithm of the WCDMA system. The proposed algorithm can acquire the synchronization of slot and frame times, and the code group identification using only one synchronization channel while the standard algorithm employs two synchronization channels called P-SCH and S-SCH. The proposed synchronization channel structure is the same as the P-SCH structure of the WCDMA system. However, the P-SCH is modulated with a specific polarization code, which is one element of new code group codes. The proposed algorithm can reduce both the BS' transmission power and the complexity of receiver as compared with the conventional one since only on synchronization channel is used. It is shown through the computer simulation that the proposed algorithm yields a significant improvement in terms of cell search time compared with the standard especially in low SNR environments.

• Tuberculosis and Respiratory Diseases
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• v.58 no.2
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• pp.120-128
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• 2005

Background : Insulin-like growth factor binding protein (IGFBP)-3 regulates non-small cell lung cancer(NSCLC) cell proliferation in vitro and in vivo by inhibiting IGF-mediated signaling pathways. To have better strategies for the treatment of lung cancer, we analyzed the combining effects of adenovirus expressing IGFBP-3 (Ad5CMV-BP3) and SCH66336, a farnesyl transferase inhibitor (FTI) designed to block Ras-mediated proliferative signaling pathways. Methods : To measure the combining effects of Ad5CMV-BP3 and SCH66336 on the proliferation of NSCLC cells, human NSCLC cell lines (H1299, H596, A549, H460, and H358), SCH66336, recombinant adenovirus expressing IGFBP-3 (Ad5CMV-BP3) and athymic nude mice were used in these experiments. Results : The combination of Ad5CMV-BP3 and SCH66336 produced a synergistic enhancement in antiproliferative effects over a range of clinically achievable concentrations in a variety of NSCLC cell lines. Furthermore, we observed a significant reduction in growth of NSCLC xenograft induced in athymic nude mice. Conclusion : In conclusion, this study demonstrated for the first time that the FTI SCH66336 synergizes with IGFBP-3 and enhances its apoptotic activity in NSCLC cells in vitro and in vivo. The combined treatment of Ad5CMV-BP3 and SCH66336 raises the possibility of using this regimen in clinic for the treatment of NSCLC.

• Korean Journal of Microbiology
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• v.32 no.1
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• pp.34-39
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• 1994

The gene encoding ${\alpha}$-amylase of Schwanniomyces castellii was cloned in Saccharomyces cerevisiae. The 5.0-kilobase insert was shown to direct the synthesis of ${\alpha}$-amylase. Southern blot analysis confirmed that this ${\alpha}$-amylase gene was derived from the genomic DNA of Sch. castellii. Immunoblot analysis showed that ${\alpha}$-amylase production from S. cerevisiae transformant was less than that of donor strain. The ${\alpha}$-amylase secreted from S. cerevisiae transformant was shown to be indistinguishable from that of Sch. castellii on the basis of molecular weight and enzyme properties.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.1-9
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• 2003

The purpose of this study is to consider the community design applications in the senior collective housing in Hyogo Prefecture, Japan. It was performed by two programs, application program and space design program. The former is focused on the participation of residents to the planing and design process, sharing, community activity, social interaction, and management by residents. The latter is focused on the common space(room) design. It was also performed by literature review, observation, and interview. The findings for the community design as an application program in SCH are almost the same with those in CH. But, the level of common meal and common laundry in SCH is lower than that of CH. And space design program is focused on the location and scale of common space(room) which is related to the number of users. As a result, the positive possibilities of SCH as a new residential type for the self-reliant seniors can be confirmed. The difference of community design application between CH and SCH is caused by various factors such as senior's health conditions, economic factors, and Japanese life style.