• Title/Summary/Keyword: surface development

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Close Surface Targets Detection using Background Removal Integral Projection in Coastal Environment (배경제거 가산투영 방법을 이용한 근거리 해상 표적 탐지)

  • Lee, Boohwan;Kim, Jieun;Yang, Yu Kyung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.1
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    • pp.115-121
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    • 2014
  • In this paper, we propose a robust background removal integral projection(BRIP) method which can detect close surface targets in coastal environment for IRST. Row pixels of background region from coastal infrared image show similar response. Thus, the proposed BRIP is calculated after horizontal and vertical background estimations and removals are performed sequentially. Finally, surface large targets can be detected using the results of the BRIP. Experimental results on a set of real infrared image sequence show that the proposed method could fully detect ships in every frame.

Abnormal oceanic conditions around the Korean peninsula caused by typhoons

  • Suh, Young-Sang;Gu, Ji-Young;Hwang, Jae-Dong;Lee, Na-Kyung;Jang, Lee-Hyun;Jeon, Kyoung-Ok
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.640-641
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    • 2003
  • Abnormal oceanic conditions associated with the passage of typhoons are examined using hydrographic and satellite data 1990-2002. During the passage period of typhoons in the Korean waters, an abrupt decrease of sea surface temperature(SST) in range of 5 to 8 $^{\circ}$ was observed. The areas of SST decrease were an order of 100-200km, and the low SST lasted about 15-25 days after passage of typhoon. After passage of typhoon, the water temperatures in the surface mixed layer of 30m show negative anomalies for quite a long period. In addition, stratification parameters were substantially decreased and chlorophyll a density was rapidly increased.

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A Development of Algorithm for Control of Surface Roughness on Ball End Mill (Ball End Mill 가공의 표면거칠기 제어 알고리즘 개발)

  • 오영생
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.03a
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    • pp.25-29
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    • 1998
  • One of the crucial problems that must be solved in a computerised unmanned machining environments requires the development of algorithm in order to predict the reliable cutting conditions on surface roughness. This paper is to develop the mathematical models for choosing the suitable cutting conditions and assist a comprehensive understanding of its machinability properties for cutting process by Ball End Mill. The mathematical equations developed to predict the surface results. It has been found that theoretical results obtained from the empirical equations agree with the experimental results of surface roughness.

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Effect of Hydrogen Concentration on Surface Oxidation Behavior of Alloy 600 in Simulated Primary Water of Pressurized Water Reactor (원전 1차측 수화학 환경에서 수소 농도가 Alloy 600의 표면산화 거동에 미치는 영향)

  • Yun Soo, Lim;Dong Jin, Kim;Sung Woo, Kim;Seong Sik, Hwang;Hong Pyo, Kim;Sung Hwan, Cho
    • Corrosion Science and Technology
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    • v.21 no.6
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    • pp.466-475
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    • 2022
  • Surface oxides and intergranular (IG) oxidation phenomena in Alloy 600 depending on hydrogen concentration were characterized to obtain clear insight into the primary water stress corrosion cracking (PWSCC) behavior upon exposure to pressurized water reactor primary water. When hydrogen concentration was between 5 and 30 cm3 H2/kg H2O, NiFe2O4 and NiO type oxides were found on the surface. NiO type oxides were found inside the oxidized grain boundary when hydrogen concentration was 5 cm3 H2/kg H2O. However, only NiFe2O4 spinel on the surface and Ni enrichment were observed when hydrogen concentration was 30 cm3 H2/kg H2O. These results indicate that the oxidation/reduction reaction of Ni in Alloy 600 depending on hydrogen concentration can considerably affect surface oxidation behavior. It appears that the formation of NiO type oxides in a Ni oxidation state and Ni enrichment in a Ni reduction (or metallic) state are common in primary water. It is believed that the above different oxidation/reduction reactions of Ni in Alloy 600 depending on hydrogen concentration can also significantly affect the resistance to PWSCC of Alloy 600.

Development of a Large Surface Mechanical Micro Machining System & Machine (대면적 미세가공시스템 및 장비 개발)

  • Park, Chun-Hong;Oh, Jeong-Seok;Shim, Jong-Youp;Hwang, Joo-Ho
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.7
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    • pp.761-768
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    • 2011
  • The large surface micro machining system includes the equipments and processes for manufacturing the ultra precision micro patterned products with large surface through the mechanical machining. Recent major issue on the micro machining technology may be the development of optical parts for the back light unit of display which has the largest market. This special issue makes up with three parts; the large surface micro machining system and machine, machining process and forming process. In this paper, the state-of-the-art and core technology of large surface micro machining system is introduced with focus on the manufacturing technology for the back light unit of LCD TV. Then, some research results on the development of a roll die lathe is introduced which involves the concept of machine design, improvement of thermal characteristics in the spindle system, improvement of relative parallelism and straightness between spindle system and long stroke feed table, machining of micro pitch patterns. Finally, the direct forming process is introduced as the future work in the large surface micro machining field.

A Study of Surface Improvement for Automotive Part by Injection Mold of Electronic Heating (전류가열 사출금형에 의한 자동차 부품의 표면개선에 관한 연구)

  • Choi, Dong-Hyuk;Hwang, Hyun-Tae;Son, Dong-Il;Kim, Daeil
    • Journal of the Korean institute of surface engineering
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    • v.51 no.1
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    • pp.40-46
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    • 2018
  • The light-weight of the research and development materials is actively carried out by overseas automobile companies and technology development continues in Korea. For the sake of fuel efficiency, the development of lightweight technology by improving the manufacturing method has been very effective. Recently, to maximize the effects of light weight, automotive interior parts have been applied by the micro-cellular injection molding using supercritical fluids and we call the Mucell manufacturing. This technique causes a problem in the quality of the surface of the products, because the shooting cells are revealed as the surface layer of the products by forming micro cells at the center of the products during injection molding. To overcome these phenomenon, we increased the temperature of injection molding using joule heating until critical value. In this study, we have predicted the problem of Mucell injection molding through the finite element analysis as changed the temperature by joule heating. From the result of finite element analysis, we have determined the optimized process and made the injection mold included electric current heating system with Mucell manufacturing analyzed the surface characteristics of the injection product according to changing mold temperature.

A Study on the Property of the Foot Form through a Development Figure of the Surface Area (발의 체표면적 특성에 관한 연구)

  • 문명옥
    • Journal of the Korean Society of Costume
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    • v.36
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    • pp.43-52
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    • 1998
  • This study was to analyze properties of the foot form through a development figure of the surface area by factor analysis, cluster analysis, and reglation analysis. This study was performed 71 college women between 19 adn 23 years old residing in Pusan urban area. The result was as follows; 1. There are four factors selected by factor analysis. The 1st factor signifies the surface area of the toe. The 2nd factor signifies the surface area between Metatarsal circumfer-ence and Tarsal circumference. The 3rd factor signifies the surface area between Toe circumference and Metatarsal circumference. The 4th factor signifies the surface area between Heel-ankle circumference. 2. There are three clusters selected by fast cluster. Cluster 1 : The foot size, most parts of foot surface area and total foot surface area are relatively small to other clusters, but the surface area between Metatarsal circumference and Tarsal circumference is relatively large to other clusters. Cluster 2 : The foot size, all parts of foot surface area and total foot surface area are relatively large to other clusters as Cluster 1, but the surface area of the sole of the heel and the ankle is relatively large to other clusters. 3. Total surface area of the foot=-274.94+24.01* Foot lengh+9.28*Metatarsal circumference.

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Cancer stem cell surface markers on normal stem cells

  • Kim, Won-Tae;Ryu, Chun Jeih
    • BMB Reports
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    • v.50 no.6
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    • pp.285-298
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    • 2017
  • The cancer stem cell (CSC) hypothesis has captured the attention of many scientists. It is believed that elimination of CSCs could possibly eradicate the whole cancer. CSC surface markers provide molecular targeted therapies for various cancers, using therapeutic antibodies specific for the CSC surface markers. Various CSC surface markers have been identified and published. Interestingly, most of the markers used to identify CSCs are derived from surface markers present on human embryonic stem cells (hESCs) or adult stem cells. In this review, we classify the currently known 40 CSC surface markers into 3 different categories, in terms of their expression in hESCs, adult stem cells, and normal tissue cells. Approximately 73% of current CSC surface markers appear to be present on embryonic or adult stem cells, and they are rarely expressed on normal tissue cells. The remaining CSC surface markers are considerably expressed even in normal tissue cells, and some of them have been extensively validated as CSC surface markers by various research groups. We discuss the significance of the categorized CSC surface markers, and provide insight into why surface markers on hESCs are an attractive source to find novel surface markers on CSCs.

Optimal Search Pattern of Ships based on Performance Surface (음향 탐지 성능 분포도 기반에서 함정 최적탐색패턴에 관한 연구)

  • Cheon, Minki;Kim, Sunhyo;Choi, Jee Woong;Choi, Cheolwoo;Son, Su-Uk;Park, Joungsoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.3
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    • pp.328-336
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    • 2017
  • The goal of this study is simulation of optimal search pattern of ships based on performance surface which are reflected underwater environmental. The process is as follows. First, temporal and spatial environmental database are extracted in complex environment and input hull mounted SONAR system parameters. The environmental database and SONAR system parameters are substituted to SONAR equations, and calculate signal excess, detection probability, detection range. And then, the performance surface, which can be used to provide operational insight of SONAR detection performance, are pictorialized. Finally, optimal search pattern of ships are simulated using genetic algorithm based on performance surface. And then, we certify optimal search pattern in various ways.

Design of an Algorithm to Simulate Surface Roughness in a Turning for an Integrated Virtual Machine Tool

  • Jang, Dong-Young
    • Proceedings of the Korea Society for Simulation Conference
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    • 1998.10a
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    • pp.204-208
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    • 1998
  • The fundamental issues to evaluate machine tool's performance through simulation pertain to the physical models of the machine tool itself and of process while the practical problems are related to the development of the modular software structure. It allows the composition of arbitrary machine/process models along with the development of programs to evaluate each state of machining process. Surface roughness is one of the fundamental factors to evaluate machining process and performance of machine tool, but it is not easy to evaluate surface roughness due to its tribological complexity. This paper presents an algorithm to calculate surface roughness considering cutting geometry, cutting parameters, and contact dynamics of cutting between tool and workpiece as well as tool wear in turning process. The designed virtual machining system can be used to evaluate the surface integrity of a turned surface during the design and process planning phase for the design for manufacturability analysis of the concurrent engineering.

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