• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1469-1474
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• 2007

In recent years, research to machine large-surface micro-features has become important because of the light guide panel of a large-scale liquid crystal display and the bipolar plate of a high-capacity proton exchange membrane fuel cell. In this study, in order to realize the systematic design technology and performance improvements of an ultra-precision machine for machining the large-surface micro-features, a structural characteristic analysis was performed using its virtual prototype. The prototype consisted of gantry-type frame, hydrostatic feed mechanisms, linear motors, brushless DC servo motor, counterbalance mechanism, and so on. The loop stiffness was estimated from the relative displacement between the tool post and C-axis table, which was caused by a cutting force. Especially, the causes of structural stiffness deterioration were identified through the structural deformation analysis of sub-models.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.249-249
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• 2010

We investigated novel surface treatment and its impact on silicon photovoltaic cells. Using 2-step etching methods, we have changed the nanostructure on pyramid surface so that less light is reflected. This work proposes an improved texturing technique of mono crystalline silicon surface for solar cells with sub-nanotexturing process. The nanotextured silicon surface exhibits a lower average reflectivity (~4%) in the wavelength range of 300-1100nm without antireflection coating layer. It is worth mentioning that the surface of pyramids may also affect the surface reflectance and carrier lifetime. In one word, we believe nanotextruing is a promising guide for texturization of monocrystalline silicon surface.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.85.5-85
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• 2002

The Master-Slave manipulator is generally used as a remote handling device in the hot cell, in which the high level radio-active materials such as spent fuels are handled. This study describes a workspace mapping algorithm for a kinematically dissimilar master-slave system The algorithm provides the operator to guide the slave's end effector into unreachable regions which can appear due to the mismatch of workspace between the master and slave manipulator. A spaceball was used for the universal master device, and it can detect the slight fingertip force applied on the ball and also resolve the applied force. The spaceball device was also used to move 3D images instantaneously and simultaneou...

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.121-125
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• 2005

Anemia can be defined as a reduction in blood hemoglobin concentration or red cell mass relative to age matched normal values. Clinical presentation may range from obviously pale and lethargy to an incidental finding during screening of an otherwise well appearing child. The differential diagnosis of anemia in each instance is broad with numerous possible etiologies. A careful history and physical examination as well as complete blood count, peripheral blood smear and additional laboratory tests are necessary in defining underlying cause of the anemia and guide in further treatment plans. In addition, Iron deficiency anemia and anemia of inflammation are common causes of mild to moderate anemia in children, but most pediatricians have some confusions to differentiate these two entities.

• Molecules and Cells
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• v.28 no.1
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• pp.1-5
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• 2009

Vascular endothelial growth factor (VEGF) is essential for many angiogenic processes both in normal and pathological conditions. However, the signaling pathways involved in VEGF-induced angiogenesis are incompletely understood. The protein kinase D1 (PKD1), a newly described calcium/calmodulin-dependent serine/threonine kinase, has been implicated in cell migration, proliferation and membrane trafficking. Increasing evidence suggests critical roles for PKD1-mediated signaling pathways in endothelial cells, particularly in the regulation of VEGF-induced angiogenesis. Recent studies show that class IIa histone deacetylases (HDACs) are PKD1 substrates and VEGF signal-responsive repressors of myocyte enhancer factor-2 (MEF2) transcriptional activation in endothelial cells. This review provides a guide to PKD1 signaling pathways and the direct downstream targets of PKD1 in VEGF signaling, and suggests important functions of PKD1 in angiogenesis.

• BMB Reports
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• v.53 no.1
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• pp.3-9
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• 2020

The mitochondrial genome encodes 13 proteins that are components of the oxidative phosphorylation system (OXPHOS), suggesting that precise regulation of these genes is crucial for maintaining OXPHOS functions, including ATP production, calcium buffering, cell signaling, ROS production, and apoptosis. Furthermore, heteroplasmy or mis-regulation of gene expression in mitochondria frequently is associated with human mitochondrial diseases. Thus, various approaches have been developed to investigate the roles of genes encoded by the mitochondrial genome. In this review, we will discuss a wide range of techniques available for investigating the mitochondrial genome, mitochondrial transcription, and mitochondrial translation, which provide a useful guide to understanding mitochondrial gene expression.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3042-3044
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• 1999

This paper presents a method for solving the path planning problem for robot manipulators. The technique allows manipulators to move from a specified starting point to a goal without colliding with objects in two dimensional environment. Approximate cell decomposition with a greedy depth-first search algorithm is used to guide the end effector though Cartesian space and genetic algorithms are used to solve the joint variable for the robot manipulators.

• Journal of Chest Surgery
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• v.54 no.4
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• pp.294-301
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• 2021

Recent case series and meta-analyses have suggested that robot-assisted minimally invasive esophagectomy (RAMIE) could be a useful alternative to video-assisted thoracic surgery esophagectomy. The advantages of RAMIE are a 3-dimensional view, 7 degrees of freedom, and tremor filtering, which enable more meticulous lymph node dissection with a lower incidence of complications. However, in radical esophagectomy, understanding the concepts of the fascia and compartment is crucial for successful and reliable dissection. The first RAMIE in Korea was performed by our team in July 2006, and since then, we have developed related techniques to achieve better short- and long-term outcomes. The key step in RAMIE for esophageal squamous cell carcinoma is dissection of the upper mediastinum due to the difficulty of lymph node dissection and the high incidence of nodal metastasis in the area. Herein, we describe the technique of fascial plane dissection with esophageal suspension during RAMIE.

• Journal of Yeungnam Medical Science
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• v.36 no.3
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• pp.163-182
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• 2019

The primary function of intraoperative frozen consultation is to provide an as accurate and prompt diagnosis as possible during surgery and to guide the surgeon in further management. However, the evaluation of frozen section (FS) is sometimes difficult because of suboptimal tissue quality and frozen artifacts compared with routinely processed tissue section. The pathologist responsible for the FS diagnosis requires experience and good judgment. Ovarian tumors are a heterogeneous group of tumors including primary surface epithelial tumors, germ cell tumors and sex cord-stromal tumors, secondary tumors, and other groups of tumors of uncertain histogenesis or nonspecific stroma. Intraoperative FS is a very important and reliable tool that guides the surgical management of ovarian tumors. In this review, the diagnostic key points for the pathologist and the implication of the FS diagnosis on the operator's decisions are discussed.

• Anatomy and Cell Biology
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• v.56 no.1
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• pp.1-8
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• 2023

From the era of pre-historic times, the ancient Indians and the Greeks highlighted the importance of body and organ donations thereby emphasizing the need for anatomical sciences in medicine through the use of effective dissections for the same. However, after the Renaissance, there was a surge in dissections throughout the world, particularly in Europe, as a result of which various laws were enacted by governments concerning the procurement of bodies for the purpose of scientific dissections, which were later promulgated throughout the world through various anatomical acts. The situation in India was quite similar to that of Britain until its independence in 1947, after which different Indian states formulated their own anatomy acts that had their own merits and pitfalls. Hence, this literature review serves to highlight the various acts throughout history and would serve as a guide to emphasize the future perspectives of formulating a centralized unified anatomy act for the Indian nation that could possibly be the need of the hour.