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비선형 순시추종형 PWM 제어기법을 적용한 강압형 DC-DC 컨버터 (The Buck DC-DC Convener with Non-Linear Instantaneous Following PWM Control Method)

  • 김상돈;라병훈;이현우;김광태
    • 조명전기설비학회논문지
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    • 제17권2호
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    • pp.73-80
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    • 2003
  • 제안된 제어 기법은 아날로그 적분기의 적분시간이 적분기 입력전압의 크기에 반비례하는 원리를 이용하여 이 펄스 변조 스위칭 컨버터를 순시 추종 제어하는 방법을 제시한다. 제안된 제어 방법은 정주파수로 동작하며 제어 스위치가 턴 온 되는 시점에서 시작하여 턴 오프 되는 시간을 아날로그 적분기를 사용하여 계산한다. 전력 변환기의 스위칭 시간을 나타내는 듀티비는 스위칭 변수의 평균치에 의하여 결정되며 추종시간은 한 사이클 내에서 이루어진다. 정상 상태는 물론 과도 상태에서도 정확하게 지령치에 추종하며, 제어기는 제어 변수의 평균치와 제어 기준값을 보정하여 제어 오차가 제로가 되게 제어한다. 제안된 제어 방법은 벅 컨버터를 사용하여 실험하였으며 이를 통하여 실험 결과와 이론이 잘 일치하고 있음을 알 수 있었다.

공기압을 이용한 전기설비 침수 방지 장치 개발에 관한 연구 (The development for flooding prevention apparatus of electrical equipment using air pressure)

  • 김기현;전현재;이상익;배석명;이재용
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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    • pp.281-284
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    • 2008
  • Inundation of substation and ground power equipment breaks out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. In case inundation excluding the exchanging cost of equipment, it occurs a great economic and social loss owing to recovery time and events of electric shock occur by inundation electrical equipment(Pad-mounted Transformer and Switch). In case of installing the power equipment at flood danger territory, we are necessary to the product development, the product is that water does not come in the inside the power equipment. Product of pressure maintaining are established on the basic frame and sensor operates at the flooding occurrence and is maintained a shutting tightly structure and it is a method. The product which is produced the reliability of the product it confirmed a flooding yes or no from the condition which puts in the water tank and it verified. We estimate that loss cost which is caused by with flooding and the power failure will be diminished if it is addition to advances the reliability evaluation and a security of the flood protection product.

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서울시 제화산업의 집적 특성 및 혁신환경 분석 (An Analysis of the Agglomeration Characteristics and Innovative Milieu of the Shoemaking Industry in Seoul)

  • 박래현
    • 대한지리학회지
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    • 제40권6호
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    • pp.653-670
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    • 2005
  • 본 연구는 서울의 경제 환경 변화와 이로 인한 어려움 속에서 전통적인 도시형 제조업이 어떠한 이유와 방식으로 위기에 대응 해가고 있는지를 밝히기 위해, 서울시 제화산업을 사례로 공간적 집적 특성과 혁신환경의 속성을 분석하였다. 분석 결과, 성수동을 중심으로 한 집적지가 성장 중에 있으며, 이 지역을 중심으로 기획 및 디자인, 생산기술, 창업 및 인력수급, 경영 등의 부문에서 국지화된 투입${\cdot}$산출관계와 관련한 정적인 효율성을 넘어 동적 집적경제가 발생할 수 있는 잠재적 요인들이 내재되어 있음을 확인하였다. 이는 최근의 동적 집적경제 접근방식이 전통적인 제조업 집적의 발생과 집적경제의 속성을 설명하는 효과적인 틀이 될 수 있다는 것을 보여주는 것이며, 바로 이러한 분석을 통해 위기에 대응해가는 현 상황에 대한 설명이 가능하다. 그러나 아직 산업을 둘러싼 외적 지원환경과 제도적 플랫폼이 체계적으로 구축되어 있지 못하여, 제화산업집적지가 보다 높은 단계의 산업집적지구로 성장${\cdot}$발전해나가기 위한 전략적 접근이 요구되고 있다.

Comparison of WHO and RECIST Criteria for Evaluation of Clinical Response to Chemotherapy in Patients with Advanced Breast Cancer

  • Khokher, Samina;Qureshi, Muhammad Usman;Chaudhry, Naseer Ahmad
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권7호
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    • pp.3213-3218
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    • 2012
  • When patients with advanced breast cancer (ABC) are treated with neoadjuvant chemotherapy (NACT), efficacy is monitored by the extent of tumor shrinkage. Since their publication in 1981, World Health Organization (WHO) guidelines have been widely practiced in clinical trials and oncologic practice, for standardized tumor response evaluation. With advances in cancer treatment and tumor imaging, a simpler criterion based on one-dimensional rather than bi-dimensional (WHO) tumor measurement, named Response Evaluation Criteria in Solid Tumors (RECIST) was introduced in 2000. Both approaches have four response categories: complete response, partial response, stable disease and progressive disease (PD). Bi-dimensional measurement data of 151 patients with ABC were analysed with WHO and RECIST criteria to compare their response categories and inter criteria reproducibility by Kappa statistics. There was 94% concordance and 9/151 patients were recategorized with RECIST including 6/12 PD cases. RECIST therefore under-estimates and delays diagnosis of PD. This is undesirable because it may delay or negate switch over to alternate therapy. Analysis was repeated with a new criteria named RECIST-Breast (RECIST-B), with a lower threshold for PD (${\geq}10%$ rather than ${\geq}20%$ increase of RECIST). This showed higher concordance of 97% with WHO criteria and re-categorization of only 4/151 patients (1/12 PD cases). RECIST-B criteria therefore have advantages of both ease of measurement and calculations combined with excellent concordance with WHO criteria, providing a practical clinical tool for response evaluation and offering good comparison with past and current clinical trials of NACT using WHO guidelines.

Unfolding of Ervatamin C in the Presence of Organic Solvents: Sequential Transitions of the Protein in the O-state

  • Sundd, Monica;Kundu, Suman;Dubey, Vikash Kumar;Jagannadham, Medicherla V.
    • BMB Reports
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    • 제37권5호
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    • pp.586-596
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    • 2004
  • The folding of ervatamin C was investigated in the presence of various fluorinated and non-fluorinated organic solvents. The differences in the unfolding of the protein in the presence of various organic solvents and the stabilities of O-states were interpreted. At pH 2.0, non-fluorinated alkyl alcohols induced a switch from the native $\alpha$-helix to a $\beta$-sheet, contrary to the $\beta$-sheet to $\alpha$-helix conversion observed for many proteins. The magnitude of ellipticity at 215 nm, used as a measure of $\beta$-content, was found to be dependent on the concentration of the alcohol. Under similar conditions of pH, fluorinated alcohol enhanced the intrinsic a-helicity of the protein molecule, whereas the addition of acetonitrile reduced the helical content. Ervatamin C exhibited high stability towards GuHCl induced unfolding in different O-states. Whereas the thermal unfolding of O-states was non-cooperative, contrary to the cooperativity seen in the absence of the organic solvents under similar conditions. Moreover, the differential scanning calorimetry endotherms of the protein acquired at pH 2.0 were deconvoluted into two distinct peaks, suggesting two cooperative transitions. With increase in pH, the shape of the thermogram changed markedly to exhibit a major and a minor transition. The appearance of two distinct peaks in the DSC together with the non-cooperative thermal transition of the protein in O-states indicates that the molecular structure of ervatamin C consists of two domains with different stabilities.

발열장치를 이용한 보온 기능성 스마트 파운데이션의 개발 및 평가 (Development and Evaluation of Smart Foundation with Heating Devices)

  • 황영미;이정란
    • 한국의류산업학회지
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    • 제15권2호
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    • pp.231-239
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    • 2013
  • This research developed a smart girdle for adult women in their 20's that has an inserted carbon weaving heater to help with relief from coldness and abdominal disease through the thermal insulation effect. A pocket of powernet fabric was attached to the inside of the girdle for the easy insertion and separation of the heating device, while the heating device was fixed to a mesh material by cotton yarn and was wrapped with elastic lining material to prevent the mechanical devices from being exposed. A set of 3 hooks was attached to the center of the back of the heating device in consideration of convenience and mobility. Whereas the switch was inserted into around the right waistband, and the battery into the inner pocket around the waist, to integrate the heating device with the girdle. The satisfaction and usability of the fabricated smart girdle was verified by having research participants wear it to evaluate the appearance change caused by the device, the inconvenience of wearing/unwearing, mobility, and the satisfactory functionality of the device. As a result, the grand mean was evaluated to be high, with appearance (4.19), mobility (4.17), and functionality (4.51) being higher than 4.00; which indicates that the heat generation function of the smart girdle is effective. It may be said that such collection and analysis of data that reflect users' opinions have value and significance in that they can be grafted onto future research on new technology as well as they contribute to taking a step forward in the rapidly increasing research of smart clothing, with the new-type clothing equipped with new function.

Blood Biochemical Profile and Rumen Fermentation Pattern of Goats Fed Leaf Meal Mixture or Conventional Cakes as Dietary Protein Supplements

  • Anbarasu, C.;Dutta, Narayan;Sharma, K.;Naulia, Uma
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권5호
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    • pp.665-670
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    • 2002
  • The expediency of replacing cost prohibitive and often inaccessible traditional protein supplements prompted the monitoring of hematological parameters was carried out in female goats at 0, 30, 60 and 90 days post feeding. Rumen environment was (3), respectively fed supplements containing either a leaf meal mixture (LMTM) of Leucaena leucocephala-Morus alba-Tectona grandis (2:1:1) or traditional protein supplements groundnut cake (GNC) or soybean meal (SBM) and wheat straw as basal diet. The periodic monitoring of hematological parameters was carried out in female goats at 0, 30, 60 and 90 days post feeding. Rumen environment was studied in bucks in a $3{\times}3$ switch over design. Rumen liquor was collected at 0, 2, 4, 6 and 8 h post feeding after 4 weeks of feeding. The goats fed on LMTM or GNC had similar dry matter intake (g/kg $W^{0.75}$), which was significantly (p<0.05) higher than SBM. Except for packed cell volume (PCV), none of the blood biochemical constituents (Hemoglobin, serum glucose, total protein, serum albumin (A) and globulin(G), A:G ratio, alkaline phosphatase, transaminases) varied significantly due to replacement of 50% dietary protein by LMTM throughout the experiment. GNC group had significantly higher level of PCV than other treatments. However, the level of serum total protein (p<0.01) tended to increase from 60th day onwards irrespective of dietary treatments. The average rumen pH was significantly higher (p<0.001) on SBM followed by LMTM and GNC, respectively. Total volatile fatty acid (TVFA) production was comparable in goats given LMTM or GNC supplements, the corresponding values were significantly different (p<0.001) when compared with SBM. The ammonical-N, total-N and TCA-precipitable-N (mg/100 ml SRL) did not differ significantly among dietary treatments. It may be concluded that supplementing wheat straw with LMTM based concentrate had no adverse effect on voluntary intake, blood biochemical profile and rumen fermentation pattern of the goats.

Could the Breast Prognostic Biomarker Status Change During Disease Progression? An Immunohistochemical Comparison between Primary Tumors and Synchronous Nodal Metastasis

  • El Nemr Esmail, Reham Shehab;El Farouk Abdel-Salam, Lubna Omer;Abd El Ellah, Mohammed M
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권10호
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    • pp.4317-4321
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    • 2015
  • Background: Prognostic biomarkers in breast cancer are routinely investigated in the primary tumors to guide further management. However, it is proposed that the expression may change during the disease progression, and may result in a different immune profile in the metastatic nodes. This work aimed to investigate the expression of breast prognostic biomarkers in primary tumors and in its axillary nodal metastasis, to estimate the possible discordant expression. Materials and Methods: 60 paired primary and axillary nodal metastasis samples were collected from patients with primary breast cancer with positive nodal deposits, diagnosed at the Maadi Military Hospital, Cairo, Egypt, during the year 2013. ER, PR and HER2 expression was assessed by immunohistochemistry in all samples Results: 48.3% of the included cases showed concordant results for both ER and PR receptors between the primary tumor and its nodal metastasis while 51.7% showed discordant results and the discordance level was statistically significant. On the other hand, 70% of the cases showed concordant Her2 results between the primary tumors and the nodal deposits, 30% showed discordant results and the difference was significant. Conclusions: The study indicated that the discordance in ER and PR receptor expression between the primary breast tumor and their nodal metastasis may be significant. The possible switch in the biomarker status during the disease progression is worth noting and may change the patient therapeutic planning. So, whether the treatment selection should be based on biomarkers in the lymph node is a topic for further studies and future clinical trials.

Phase II Study on Voriconazole for Treatment of Chinese Patients with Malignant Hematological Disorders and Invasive Aspergillosis

  • Zhang, Xue-Zhong;Huang, Xin-En;Xu, Yan-Li;Zhang, Xiu-Qun;Su, Ai-ling;Shen, Zheng-Shan
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.2415-2418
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    • 2012
  • Objective: To investigate the efficacy and safety of voriconazole in treating Chinese patients with hematological malignancies and invasive aspergillosis. Methods: From March 2007 to April 2012, patients with diagnoses confirmed by CT, GM test and/or PCR assays, were recruited into this study. Aspergillosis of all patients were treated with voriconazole 6 mg/kg intravenous infusion (iv) every 12 h for 1 day, followed by 4 mg/kg IV every 12 h for 10-15 days; Then, switch to oral administration that was 200mg every 12h for 4-12 weeks. Efficacy and safety were evaluated according to Practice Guideline of Infectious Diseases Society of America. Results: The overall response rate of 38 patients after voriconazole treatment was 81.6%. The median time to pyretolysis was 4.5 days. Treatment related side effects were mild and found in only 15.8% of cases. No treatment related deaths occurred. Conclusions: Voriconazole can considered to be a safe and effective front-line therapy to treat patients with hematological malignancies and invasive aspergillosis. Alternatively it could be used as a remedial treatment when other antifungal therapies are ineffective.

저관여 상품구매의 소비자 행동특성에 관한 연구 (A Study on Consumer Behavior Characteristic of Low Involvement Goods Purchasing)

  • 김문정;조윤기
    • 유통과학연구
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    • 제6권2호
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    • pp.81-93
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    • 2008
  • 본 연구는 저관여 상품을 구매하는 소비자의 행동특성을 알아보기 위하여 저관여 상표로 분류되는 캔커피 구매 시 영향을 미치는 요인 및 장소 등에 관해 분석함으로서 마케팅 요소 중 어떠한 요소가 구매자의 구매결정에 영향을 미치는가를 조사하여 마케팅 믹스의 최적배합에 관한 근거를 제시하고자 하였다. 실증분석 결과 크게 영향을 미치는 요인은 제품의 만족도가 아닌, 유통이나 인지도(홍보)에 있었다. 제품의 만족도가 낮은 구매자들이 타 상표로 이동하는 것이 없는 것은 아니었으나, 이는 예상했던 것보다 상당히 낮은 수준으로 나타났고, 오히려 만족도가 낮은 고객도 다시 그 상표를 구매하겠다는 구매의사를 밝혔다. 본 연구는 저 관여상품의 구매에서 마케팅 믹스 중 유통요소나 인지도요소가 제품요소보다 중요하게 나타나 저 관여 상품 판매에 다양한 촉진요소의 필요성을 알 수 있었다.

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