• 제목/요약/키워드: cause of defects

검색결과 624건 처리시간 0.023초

Regulation of ANKRD9 expression by lipid metabolic perturbations

  • Wang, Xiaofei;Newkirk, Robert F.;Carre, Wilfrid;Ghose, Purnima;Igobudia, Barry;Townsel, James G.;Cogburn, Larry A.
    • BMB Reports
    • /
    • 제42권9호
    • /
    • pp.568-573
    • /
    • 2009
  • Fatty acid oxidation (FAO) defects cause abnormal lipid accumulation in various tissues, which provides an opportunity to uncover novel genes that are involved in lipid metabolism. During a gene expression study in the riboflavin deficient induced FAO disorder in the chicken, we discovered the dramatic increase in mRNA levels of an uncharacterized gene, ANKRD9. No functions have been ascribed to ANKRD9 and its orthologs, although their sequences are well conserved among vertebrates. To provide insight into the function of ANKRD9, the expression of ANKRD9 mRNA in lipidperturbed paradigms was examined. The hepatic mRNA level of ANKRD9 was repressed by thyroid hormone ($T_3$) and fasting, elevated by re-feeding upon fasting. However, ANKRD9 mRNA level is reduced in response to apoptosis. Transient transfection assay with green fluorescent protein tagged- ANKRD9 showed that this protein is localized within the cytoplasm. These findings point to the possibility that ANKRD9 is involved in intracellular lipid accumulation.

CONVERGENCE ANALYSIS OF THE EAPG ALGORITHM FOR NON-NEGATIVE MATRIX FACTORIZATION

  • Yang, Chenxue;Ye, Mao
    • Journal of applied mathematics & informatics
    • /
    • 제30권3_4호
    • /
    • pp.365-380
    • /
    • 2012
  • Non-negative matrix factorization (NMF) is a very efficient method to explain the relationship between functions for finding basis information of multivariate nonnegative data. The multiplicative update (MU) algorithm is a popular approach to solve the NMF problem, but it fails to approach a stationary point and has inner iteration and zero divisor. So the elementwisely alternating projected gradient (eAPG) algorithm was proposed to overcome the defects. In this paper, we use the fact that the equilibrium point is stable to prove the convergence of the eAPG algorithm. By using a classic model, the equilibrium point is obtained and the invariant sets are constructed to guarantee the integrity of the stability. Finally, the convergence conditions of the eAPG algorithm are obtained, which can accelerate the convergence. In addition, the conditions, which satisfy that the non-zero equilibrium point exists and is stable, can cause that the algorithm converges to different values. Both of them are confirmed in the experiments. And we give the mathematical proof that the eAPG algorithm can reach the appointed precision at the least iterations compared to the MU algorithm. Thus, we theoretically illustrate the advantages of the eAPG algorithm.

사례 분석을 통한 김치냉장고의 화재 위험성에 관한 연구 (A Study on the Fire Risk of the Kimchi Refrigerator through Case Analysis of Fire Accidents)

  • 박남규;지홍근;송재용
    • 한국안전학회지
    • /
    • 제35권2호
    • /
    • pp.1-7
    • /
    • 2020
  • In this paper, we describe fire risk of Kimchi refrigerator. The Kimchi refrigerator has been widely spread and used starting from the first half of 2000 and recently fire accidents caused by the Kimchi refrigerator emerged as social concern. In particular, in products of a specific manufacturer, it is not an environmental factor, but a characteristic that the fire is caused due to a defect of the product itself is shown. These features are judged to be formed by unique defects regardless of external factor by forming electrically arc mark in the relay element. In this paper, we analyzed the cause of the fire occurring in the Kimchi refrigerator and finally confirmed the characteristic that the fire occurred mainly in the relay element due to insufficient capacity of the relay element. Therefore, when a fire occurs in a product of the same maker as the Kimchi refrigerator mentioned in this paper, it is always judged that the inspection of the relay element should be carried out.

충격반향기법을 이용한 깊은 기초의 건전도 평가(수치해석) (Integrity Evaluation of Deep Foundations by Using Impact Echo Method(Numerical Study))

  • 김동수;박연홍
    • 한국지반공학회논문집
    • /
    • 제15권2호
    • /
    • pp.139-152
    • /
    • 1999
  • 근래에 들어 구조물의 대형화에 따라 현장타설 말뚝을 하부 구조물로서 광범위하게 적용하고 있다. 그러나 현장타설 말뚝에 결함이 생기면 상부 하중에 대한 지지력 저하와 함께 침하량이 증가하게 되어 상부 구조물에 치명적인 손실을 초래할 수 있다. 따라서 비파괴시험 기법에 의한 콘크리트 말뚝의 효과적인 건전도 평가기법 개발이 중요하게 대두되고 있다. 본 연구에서는 수치해석을 통하여 콘크리트 말뚝의 건전도 평가에 이용되는 충격반향기법의 적용성을 검토하였다. 3차원 축대칭 유한요소법을 이용하여 건전한 말뚝과 현장타설 말뚝의 전형적인 결함인 병목, 공동, 불량 콘크리트를 포함하는 말뚝, 그리고 지반 및 암반위에 놓인 말뚝에 관한 해석을 수행하였다. 해석결과 현장타설 말뚝에 적용되는 충격반향기법의 적용성 평가에 있어서 유한요소법이 효과적임을 알 수 있었다.

  • PDF

Computer Aided Identification of Inter-Layer Faults in Gas Insulated Capacitively Graded Bushing during Switching

  • Rao, M.Mohana;Dharani, P.;Rao, T. Prasad
    • Journal of Electrical Engineering and Technology
    • /
    • 제4권1호
    • /
    • pp.28-34
    • /
    • 2009
  • In a Gas Insulated Substation (GIS), Very Fast Transients (VFTs) are generated mainly due to switching operations. These transients may cause internal faults, i.e., layer-to-layer faults in a capacitively graded bushing as it is one of the most important terminal equipment for GIS. The healthiness of the bushing is generally verified by measuring its leakage current. However, the change in current magnitude/pattern is only marginal for different types of fault conditions. Leakage current monitoring (LCM) systems generate large amounts of data and computer aided interpretation of defects may be of great assistance when analyzing this data. In view of the above, ANN techniques have been used in this study for identification of these minor faults. A single layer perceptron network, a two layer feed-forward back propagation network and cascade correlation (CC) network models are used to identify interlayer faults in the bushing. The effectiveness of the CC network over perceptron and back propagation networks in identification of a fault has been analysed as part of the paper.

Alk3/Alk3b and Smad5 Mediate BMP Signaling during Lymphatic Development in Zebrafish

  • Kim, Jun-Dae;Kim, Jongmin
    • Molecules and Cells
    • /
    • 제37권3호
    • /
    • pp.270-274
    • /
    • 2014
  • Lymphatic vessels are essential to regulate interstitial fluid homeostasis and diverse immune responses. A number of crucial factors, such as VEGFC, SOX18, PROX1, FOX2C, and GJC2, have been implicated in differentiation and/or maintenance of lymphatic endothelial cells (LECs). In humans, dysregulation of these genes is known to cause lymphedema, a debilitating condition which adversely impacts the quality of life of affected individuals. However, there are no currently available pharmacological treatments for lymphedema, necessitating identification of additional factors modulating lymphatic development and function which can be targeted for therapy. In this report, we investigate the function of genes associated with Bone Morphogenetic Protein (BMP) signaling in lymphatic development using zebrafish embryos. The knock-down of BMP type II receptors, Bmpr2a and Bmpr2b, and type I receptors, Alk3 and Alk3b, as well as SMAD5, an essential cellular mediator of BMP signaling, led to distinct lymphatic defects in developing zebrafish. Therefore, it appears that each constituent of the BMP signaling pathway may have a unique function during lymphatic development. Taken together, our data demonstrate that BMP signaling is essential for normal lymphatic vessel development in zebrafish.

Anomaly detection of isolating switch based on single shot multibox detector and improved frame differencing

  • Duan, Yuanfeng;Zhu, Qi;Zhang, Hongmei;Wei, Wei;Yun, Chung Bang
    • Smart Structures and Systems
    • /
    • 제28권6호
    • /
    • pp.811-825
    • /
    • 2021
  • High-voltage isolating switches play a paramount role in ensuring the safety of power supply systems. However, their exposure to outdoor environmental conditions may cause serious physical defects, which may result in great risk to power supply systems and society. Image processing-based methods have been used for anomaly detection. However, their accuracy is affected by numerous uncertainties due to manually extracted features, which makes the anomaly detection of isolating switches still challenging. In this paper, a vision-based anomaly detection method for isolating switches, which uses the rotational angle of the switch system for more accurate and direct anomaly detection with the help of deep learning (DL) and image processing methods (Single Shot Multibox Detector (SSD), improved frame differencing method, and Hough transform), is proposed. The SSD is a deep learning method for object classification and localization. In addition, an improved frame differencing method is introduced for better feature extraction and a hough transform method is adopted for rotational angle calculation. A number of experiments are conducted for anomaly detection of single and multiple switches using video frames. The results of the experiments demonstrate that the SSD outperforms the You-Only-Look-Once network. The effectiveness and robustness of the proposed method have been proven under various conditions, such as different illumination and camera locations using 96 videos from the experiments.

STD11 금형강 재열처리에 따른 미세조직 및 기계적 특성 (Microstructure and Mechanical Properties of STD11 Steel According to Reheat Treatment)

  • 박기연;권의표;허기호
    • 한국재료학회지
    • /
    • 제32권3호
    • /
    • pp.139-145
    • /
    • 2022
  • Reheat treatment process of mold is necessary when partial machining of the mold is required, such as shape correction for an existing mold. If defects such as cracks or significant deterioration of mechanical properties of the mold occur during reheat treatment, it is impossible to reuse the mold. In this study, reheat treatment was performed up to two times for STD11 tool steel, and microstructure and mechanical properties according to the reheat treatment were evaluated. Carbide fraction and grain size of prior austenite were almost unchanged after the reheat treatment. Hardness and impact toughness increased significantly after QT treatment, and these properties were maintained without significant change even after the reheat treatment. It is concluded that up to two iterations of reheat treatment does not cause deterioration of properties of STD11 tool steel. Based on these results, a mold for a face-lifted front bumper was manufactured through machining and reheat-treating of an existing mold.

Prevention and treatment of microstomia

  • Sae Hwi Ki;Tae Jun Park
    • 대한두개안면성형외과학회지
    • /
    • 제25권3호
    • /
    • pp.105-115
    • /
    • 2024
  • The mouth, located in the lower third of the face, is a uniquely visible structure. It serves as a vital organ both aesthetically and functionally, playing a key role in speech, expression, and fundamental oral functions. Consequently, any alterations or defects in its shape, due to various causes, can lead to aesthetic and functional deficiencies. These issues may also result in challenges with social interactions and a decrease in confidence. In cases of microstomia, various surgical approaches are proposed based on the location, extent, shape, and cause of the defect, leading to numerous case reports. Plastic surgeons are proficient in oral reconstruction; however, cases of microstomia are relatively rare, which reduces their familiarity and interest in these cases. Additionally, preferences for oral size and shape vary according to factors such as geographical region and ethnicity, further complicating the functional definition of microstomia. Therefore, both subjective patient and physician judgments play crucial roles in the diagnosis and treatment of microstomia, as these may vary depending on individual and societal aspects. This review aims to classify the various causes and definitions of microstomia, as well as its non-surgical and surgical treatment options, with the goal of the treatment of this condition.

Automated Analysis Technique Developed for Detection of ODSCC on the Tubes of OPR1000 Steam Generator

  • Kim, In Chul;Nam, Min Woo
    • 비파괴검사학회지
    • /
    • 제33권6호
    • /
    • pp.519-523
    • /
    • 2013
  • A steam generator (SG) tube is an important component of a nuclear power plant (NPP). It works as a pressure boundary between the primary and secondary systems. The integrity of a SG tube can be assessed by an eddy current test every outage. The eddy current technique(adopting a bobbin probe) is currently the main technique used to assess the integrity of the tubing of a steam generator. An eddy current signal analyst for steam generator tubes continuously analyzes data over a given period of time. However, there are possibilities that the analyst conducting the test may get tired and cause mistakes, such as: missing indications or not being able to separate a true defect signal from one that is more complicated. This error could lead to confusion and an improper interpretation of the signal analysis. In order to avoid these possibilities, many countries of opted for automated analyses. Axial ODSCC (outside diameter stress corrosion cracking) defects on the tubes of OPR1000 steam generators have been found on the tube that are in contract with tube support plates. In this study, automated analysis software called CDS (computer data screening) made by Zetec was used. This paper will discuss the results of introducing an automated analysis system for an axial ODSCC on the tubes of an OPR1000 steam generator.