• Title/Summary/Keyword: defect factor

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A Study on the Apartments Remodeling for User-Oriented Design -Focused on the Gwang-ju, Jun-nam province- (거주자 중심의 아파트 리모델링에 관한 연구 - 광주.전남지역 아파트 대상으로 -)

  • 이향미;이청웅
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2002.11a
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    • pp.183-187
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    • 2002
  • This study researched that the remodeling was executed desirably in the side of deweller's household to the subject of ten apartment housings located in Gwang-ju, Jun-nam province. The study method was used the field study method and used in parallel with participant observation. As a result of the study, first, the problems of remodeling enforcement process are brought about standardized design, bad construction and the difficulty of solution in the defect occurrence. Second, By that request of the household is not reflected, the room except bedroom and the bathroom of inner room are low practical use degree. And wash space, garden space, assistant space of kitchen work were becoming hindrance factor of the residing environment because the use is irrational.

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Diode Equivalent Parameters of Solar Cell

  • Iftiquar, Sk Md;Dao, Vinh Ai;Yi, Junsin
    • Current Photovoltaic Research
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    • v.3 no.4
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    • pp.107-111
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    • 2015
  • Current characteristic curve of an illuminated solar cell was used to determine its reverse saturation current density ($J_0$), ideality factor (n) and resistances, by using numerical diode simulation. High efficiency amorphous silicon, heterojunction crystalline Si (HIT), plastic and organic-inorganic halide perovskite solar cell shows n=3.27 for a-Si and n=2.14 for improved HIT cell as high and low n respectively, while the perovskite and plastic cells show n=2.56 and 2.57 respectively. The $J_0$ of these cells remain within $7.1{\times}10^{-7}$ and $1.79{\times}10^{-8}A/cm^2$ for poorer HIT and improved perovskite solar cell respectively.

Utility Interactive Photovoltaic Generation System using a Space Vector Modulation (공간벡터 변조방식을 이용한 계통연계형 태양광발전시스템)

  • Cho, Moon-Taek;Lee, Chung-Sik;Lee, Sang-Cheol
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.4
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    • pp.345-350
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    • 2010
  • This paper presents a Photovoltaic Generation system using a Space Vector Modulation. PWM voltage source inverter using inverter consists of complex type of electric power converter to compensate for the defect, that is solar cell cannot be developed continuously by connecting with the source of electric power for ordinary use. It can cause the effect of saving electric power, from 10 to 20[%]. Synchronous signal and control signal was processed by the 56F8323 microprocessor for stable modulation. Also, Waveforms output current and voltage of system controlled so that phase conforms and can supply electric power that stabilize by the unit power factor.

A Study on Structure Analysis and Fatigue Life of the Common Rail Pipe (커먼레일 파이프의 구조해석 및 피로수명에 관한 연구)

  • Song, M.J.;Jung, S.Y.;Hwang, B.C.;Kim, C.
    • Transactions of Materials Processing
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    • v.19 no.2
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    • pp.88-94
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    • 2010
  • The next generation of diesel engine can operate at high injection pressure up to 1,800bar. The common rail pipe must have higher internal strength because it is directly influenced by the high-pressure fuel. Folding defects in the Common rail pipe can not ensure the structural safety. Therefore, Preform design and fatigue-life analysis are very important for preventing the head of the common rail pipe from folding in the heading process and for predicting fatigue life according to the amount of folding. In this study, a closed form equation to predict fatigue life was suggested by Goodman theory and pressure vessels theory in ASME Code in order to develop an optimization technique of the heading process and verified its reliability through fatigue-structural coupled field analysis. The results calculated by the theory were in good agreement with those obtained by the finite element analysis.

Statistical Analysis on the Correlation Between tile Defects in Apartment Houses and Environmental Factors (공동주택 내 타일 하자와 환경적 요인의 연관성에 대한 통계분석)

  • Pyeon, Su-Jeong;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Lee, Sang-Soo;Lee, Yea-chan;Nam, Jeong-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.11a
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    • pp.56-57
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    • 2021
  • Apartments, an intensive residential type, exist and are supplied in large quantities regardless of the size of the city. The value of an apartment is affected not only by the surrounding infrastructure, but also in terms of maintenance. Defects that occur in apartments come in various forms, and mainly poor finishing accounts for 60% of the defects. Among them, tile defects accounted for a large proportion and were found to be caused by several factors. This paper analyzed the influence of each factor considering the coefficient of thermal expansion affecting tile defects according to the domestic seasonal climate.

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CUBN mutation: a benign genetic cause of proteinuria?

  • Hyun Kyung Lee
    • Childhood Kidney Diseases
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    • v.27 no.1
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    • pp.19-25
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    • 2023
  • Proteinuria is an important risk factor for renal and cardiovascular disease. It is associated with a risk for glomerulonephritis, chronic kidney disease, and end-stage renal disease. Therefore, if persistent proteinuria is detected, kidney biopsy is considered to diagnose and treat the underlying disease. Recently, variants in the cubilin (CUBN) gene, which is associated with albuminuria, have been reported. This gene encodes cubilin, a membrane glycoprotein receptor expressed in the renal proximal tubules. Cubilin is a component of the megalin and cubilin-amnionless complex that mediates albumin reabsorption into the proximal tubules through endocytosis. A defect in cubilin leads to a reduction in albumin reuptake, resulting in albumin-dominant proteinuria. Although numerous controversies exist, several reports suggest that cubilin defects lead to proteinuria with a high portion of albuminuria but may not impair renal filtration function. If albuminuria due to reduced cubilin function is confirmed as a benign condition, we can consider using genetic studies to detect CUBN mutations in patients with proteinuria and they may not require any treatment or kidney biopsy. Here, we review recent papers on CUBN mutations and discuss the prognosis and management of individuals with this mutation.

Treatment of cemental tear associated with periapical lesion using regenerative surgery; A case report (재생술식을 이용한 치근단 병소를 동반한 백악질 열리의 치료)

  • Kang, Hyo-Jin;Jung, Gyu-Un;Pang, Eun-Kyoung
    • The Journal of the Korean dental association
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    • v.54 no.5
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    • pp.365-373
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    • 2016
  • Purpose: Cemental tear is a specific type of root surface fracture characterized by a complete separation of a cemental fragment along the cementodentinal junction or a partial split within the cementum along an incremental line. It is suggested to be a factor for periodontal or periapical tissue destruction. The aim of this study is to present a diagnosis and treatment of cemental tear associated with periapical lesion with root canal treatment and regenerative periodontal surgery. Treatments: A 60-year-old male who had a history of sports trauma on the mandibular right central incisor about 10 years ago presented with apical cemental tear. Clinical examination showed a slightly dark yellowish discoloration and sinus tract that was located on the apical labial mucosa. The mobility and percussion were also assessed on the diseased tooth and recorded as $Miller^{\circ}{\phi}s$ Class II and tenderness to percussion. The probing depth was within the normal limit (<3 mm). Radiographic examination revealed a radiolucent lesion at the apical area and extended to distal aspect of the tooth along the fragment of cemental tear. After root canal treatment, periapical surgery was performed. The bony defect was exposed and then the detached root fragment was removed. Apical root resection and retrograde filling with Mineral Trioxide Aggregate (MTA) were accomplished and the bony defect was filled with deproteinized bovine bone mineral (DBBM) and covered with biodegradable collagen membrane. Results: After 9-month follow-up, healing of the mandibular right central incisor was uneventful and no swelling, purulence or pain was revealed in the associated area. Probing pocket depth was favorably stable, and the tooth mobility was decreased to the Miller's Class I. Conclusions: Apical cemental tear associated periapical lesion could be successfully treated with removal of the detached cementum in combination with apical surgery and GTR procedure.

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Effect of Se Flux and Se Treatment on the Photovoltaic Performance of β-CIGS Solar Cells

  • Kim, Ji Hye;Cha, Eun Seok;Park, Byong Guk;Ahn, Byung Tae
    • Current Photovoltaic Research
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    • v.3 no.2
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    • pp.39-44
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    • 2015
  • $Cu(In,Ga)_3Se_5$ (${\beta}-CIGS$) has a band gap of 1.35 eV which is an optimum value for high solar-energy conversion efficiency. However, ${\beta}-CIGS$ film was not well characterized yet due to lower efficiency compared to $Cu(In,Ga)Se_2$ (${\alpha}-CIGS$). In this work, ${\beta}-CIGS$ films were fabricated by a three-stage co-evaporation of elemental sources with various Se fluxes. As the Se flux increased, the crystallinity of ${\beta}-CIGS$ phase was improved from the analysis of Raman spectroscopy and a deep-level defect was reduced from the analysis of photoluminescence spectroscopy. A Se treatment of the ${\beta}-CIGS$ film at $200^{\circ}C$ increased Ga content and decreased Cu content at the surface of the film. With the Se treatment at $200^{\circ}C$, the cell efficiency was greatly improved for the CIGS films prepared with low Se flux due to the increase of short-circuit current and fill factor. It was found that the main reason of performance improvement was lower Cu content at the surface instead of higher Ga content.

Histological Evaluation on the Biocompatibility and Degradation of Poly Lactic-co Glycolic Acid (PLGA)/Inorganic Filler Matrix in Surgically Created Intrabony 1-wall Defect in Beagle Dog. (비글견 1벽성 골내낭에서 Poly Lactic-co Glycolic Acid (PLGA)/Inorganic Filler Matrix의 생체 친화성 및 흡수성에 대한 조직학적 연구)

  • Lee, Jae-Youn;Kim, Chong-Kwan
    • The Journal of the Korean dental association
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    • v.47 no.6
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    • pp.364-372
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    • 2009
  • 치주 질환으로 인하여 소실된 치주조직을 재생시키려는 여러 술식이 많이 연구되고있다. 그 중 bioactive factor의 적용은 치주조직의 재생에 있어서 우수한 치료법으로 평가되고 있으며, 이를 수용부에 적절히 적용하기 위한 운반체로 생체친화적인 중합체가 이용되고 있다. 본 연구의 목적은 PLGA를 Inorganic filler에 혼합시킨 재료를 성견의 일벽성 골내낭에 적용하여 이 재료의 생체 친화성과 생체 흡수도를 보고자 하는 것이다. 5마리의 비글견에서 제 3 소구치를 모두 발치한 뒤, 8주간의 치유기간이 지나고 제 2 소구치 원심면과 제 4 소구치 근심면에 5mm 깊이, 4mm폭의 일벽성 골내낭을 형성하였다. 좌측 defect에는 PLGA/inorganic filler matrix를 이식하였고 우측에는 아무것도 이식하지 않은 대조군으로 나누어 술 후 8주에 희생하여 치유 결과를 조직학적으로 비교 관찰하였다. 조직학적 분석 결과, 모든 결손부에서 염증의 소견이 관찰되지 않았으며 치근흡수와 유착은 발견되지 않았다. 백악질과 치조골, 치주인대를 포함한 치주조직의 재생에 있어서 대조군, 실험군 간에 조직학적으로 치유양상에 있어 차이를 많이 보이지 않았으며 PLGA/inorganic filler matrix는 8주 내에 완전히 흡수되어 결합조직이나 신생골내에서 그 흔적을 발견할 수 없었다. 이러한 결과는 PLGA/inorganic filler matrix는 생체친화성 및 생체흡수성이 우수한 재료로서 치주 조직의 재생 치료에 있어서 신체활성인자의 scaffold로 사용될 수 있는 가능성을 보여주었다.

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The TDDB Characteristics of Thin $SiO_2$ with Stress Voltage Polarity (스트레스전압 극성에 따른 얇은 산화막의 TDDB 특성)

  • Kim, Cheon-Soo;Yi, Kyoung-Soo;Nam, Kee-Soo;Lee, Jin-Hyo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.5
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    • pp.52-59
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    • 1989
  • The reliability of the thin thermal oxide was investigated by using constant current stress method. Polysilicon gate MOS capacitors with oxide thickness range of 20-25nm were used in this experiment. Automatic measurement and statistical data analysis which were essential in reliability evaluation of VLSI process preformed by HP 9000 computer. Based on TDDB results, defect density, breakdown charge (Qbd) and lifetime of oxide film were evaluated. According to the polarity of the stress, some different characteristics were shown. Defect density was 62/$cm^2$ at negative gate injection. The value of Qbd was about 30C/$cm^2$ at positive gate injection, and about 21C/$cm^2$ at negative. The current density acceleration factor was 1.43$cm^2$/A for negative gate injection, and 1.25$cm^2$/A for positive gate injection.

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