• Title/Summary/Keyword: gap k-joint

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SEISMIC ISOLATION OF LEAD-COOLED REACTORS: THE EUROPEAN PROJECT SILER

  • Forni, Massimo;Poggianti, Alessandro;Scipinotti, Riccardo;Dusi, Alberto;Manzoni, Elena
    • Nuclear Engineering and Technology
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    • v.46 no.5
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    • pp.595-604
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    • 2014
  • SILER (Seismic-Initiated event risk mitigation in LEad-cooled Reactors) is a Collaborative Project, partially funded by the European Commission in the $7^{th}$ Framework Programme, aimed at studying the risk associated to seismic-initiated events in Generation IV Heavy Liquid Metal reactors, and developing adequate protection measures. The project started in October 2011, and will run for a duration of three years. The attention of SILER is focused on the evaluation of the effects of earthquakes, with particular regards to beyond-design seismic events, and to the identification of mitigation strategies, acting both on structures and components design. Special efforts are devoted to the development of seismic isolation devices and related interface components. Two reference designs, at the state of development available at the beginning of the project and coming from the $6^{th}$ Framework Programme, have been considered: ELSY (European Lead Fast Reactor) for the Lead Fast Reactors (LFR), and MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) for the Accelerator-Driven Systems (ADS). This paper describes the main activities and results obtained so far, paying particular attention to the development of seismic isolators, and the interface components which must be installed between the isolated reactor building and the non-isolated parts of the plant, such as the pipe expansion joints and the joint-cover of the seismic gap.

A Study on the Development of High Deposition Automatic Vertical Welding of Erection Stage in Shipbuilding (조선 탑재용접용 대입열 수직자동용접법의 개발에 관한 연구)

  • Park, Ju-Yong;Choe, Woo-Hyeon
    • Journal of Welding and Joining
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    • v.26 no.5
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    • pp.66-73
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    • 2008
  • Welding work in pre-erection or erection stage of shipbuilding construction to be carried out in flat and vertical upward position mostly and Electrogas welding(EGW) is actively applied especially for vertical butt joint of thicker steel plate recently. In this study considered how to develope and improve mechanical properties of weld metal and HAZ in high heat input welding processes such as EGW and Electroslag welding(ESW) with its welding equipment in order to extend the application range to the longitudinal members and hatch coaming parts of container ship. Some components of welding system and parameters were modified to get the faster travel speed and reduce weld heat input, and also by adding additional filler rods or tubes increase the amount of deposited weld metal. With the test get some good date can apply to actual fabrication work and recommend items to manufacture welding materials make better. Above all things it's a fruition that to prepare the possibility of application of ESW to shipbuilding construction which fill up the gap of stoppage days of more than 20 years.

Growth features and nucleation mechanism of Ga1-x-yInxAlyN material system on GaN substrate

  • Simonyan, Arpine K.;Gambaryan, Karen M.;Aroutiounian, Vladimir M.
    • Advances in nano research
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    • v.5 no.4
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    • pp.303-311
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    • 2017
  • The continuum elasticity model is applied to investigate quantitatively the growth features and nucleation mechanism of quantum dots, nanopits, and joint QDs-nanopits structures in GaInAlN quasyternary systems. We have shown that for GaInAlN material system at the critical strain of ${\varepsilon}^*=0.039$ the sign of critical energy and volume is changed. We assume that at ${\varepsilon}={\varepsilon}^*$ the mechanism of the nucleation is changed from the growth of quantum dots to the nucleation of nanopits. Obviously, at small misfit (${\varepsilon}$ < ${\varepsilon}^*$), the bulk nucleation mechanism dominates. However, at ${\varepsilon}$ > ${\varepsilon}^*$, when the energy barrier becomes negative as well as a larger misfit provides a low-barrier path for the formation of dislocations, the nucleation of pits becomes energetically preferable. The free energy of mixing for $Ga_{1-x-y}In_xAl_yN$ quasiternary system was calculated and studied and its 3D sketch was plotted.

An Availability Analysis on the Gap K-Joints using High Strength Circular Hollow Section Members (고강도 원형강관 갭K형 접합의 사용성 해석)

  • Ahn, Kwan-Su;Choi, Byong-Jeong;Oh, Young-Suk;Kim, Jae-Woon
    • Journal of Korean Society of Steel Construction
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    • v.22 no.2
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    • pp.109-119
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    • 2010
  • There are many restrictions in the application of high-strength HSSs, including yield strength and yield ratio for the 600-MPa steel. The AISC and Canadian codes recommend that the yield strength and yield ratio of HSS members be 360 MPa and 80%, respectively. It is important to understand the true buckling behaviors of HSSs using high-strength steel at the limit states. There are many experimental data regarding the rectangular HSSs, and the circular ones are not enough for high-strength steel. Therefore, this study was conducted to create a better understanding of the buckling behaviors of the 600- and 400-MPa steels based on the results of the finite-element analysis that was done before the experiment. To understand the structural behaviors of the aforementioned steels, the width-to-thickness ratios, the angle of the web members, the yield strength, and the gap of the web members were selected as the main parameters in this study, and ABAQUS, a general finite-element program, was used.As a result, the compression web member reached elastic buckling in the 600-MPa steel and inelastic buckling in the 400-MPa steel. A brittle fracture occurred in the case where the yield ratio was greater than 80%. At the same time, it was found that the limit strength determined via FEM analysis had a higher value compared to the code evaluation with the variation of the width-to-thickness ratio in the main code member. The change in the connection load in high-strength steels was not identified by the other factors.

A Study of Whether Extinctive Prescription and Joint Payment Apply to the Right of Imposing Fine on the Law of National Health Insurance or Not ("국민건강보험법" 상 과징금부과처분 권한에 대한 소멸시효 적용여부 및 과징금 연대 납부 의무 유무)

  • Park, Tae-Shin
    • The Korean Society of Law and Medicine
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    • v.12 no.2
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    • pp.189-217
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    • 2011
  • According to the current law of national health insurance, the Minister of Health and Welfare can impose a suspension of business or license, and a fine with medical institutions who violate the law. In case that medical institutions raise an action for ity with each penalty, they ask for replacing the suspension of business with a fine during the pendency of the action. But there is a long gap of time between an offense and administrative measures. One violation cause several types of administrative measures (suspension of business or fine, suspension of license etc.) and different government departments impose these penalties. It takes a lot of time to organize their opinions and they are liable to impose penalties after considerable space of time because of overwhelming tasks. Then the medical institutions can sustain a loss by getting unexpected administrative measures after their offense against the law. Thus, this article review whether extinctive prescription apply to the right of imposing fine on the law of national health insurance or not. Meanwhile, we have no regulations imposing a same fine to co-representatives of medical institution who infringe the law of national health insurance. On this point, this study review whether they have equal duty on that or not.

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A study on measurement and compensation of automobile door gap using optical triangulation algorithm (광 삼각법 측정 알고리즘을 이용한 자동차 도어 간격 측정 및 보정에 관한 연구)

  • Kang, Dong-Sung;Lee, Jeong-woo;Ko, Kang-Ho;Kim, Tae-Min;Park, Kyu-Bag;Park, Jung Rae;Kim, Ji-Hun;Choi, Doo-Sun;Lim, Dong-Wook
    • Design & Manufacturing
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    • v.14 no.1
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    • pp.8-14
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    • 2020
  • In general, auto parts production assembly line is assembled and produced by automatic mounting by an automated robot. In such a production site, quality problems such as misalignment of parts (doors, trunks, roofs, etc.) to be assembled with the vehicle body or collision between assembly robots and components are often caused. In order to solve such a problem, the quality of parts is manually inspected by using mechanical jig devices outside the automated production line. Automotive inspection technology is the most commonly used field of vision, which includes surface inspection such as mounting hole spacing and defect detection, body panel dents and bends. It is used for guiding, providing location information to the robot controller to adjust the robot's path to improve process productivity and manufacturing flexibility. The most difficult weighing and measuring technology is to calibrate the surface analysis and position and characteristics between parts by storing images of the part to be measured that enters the camera's field of view mounted on the side or top of the part. The problem of the machine vision device applied to the automobile production line is that the lighting conditions inside the factory are severely changed due to various weather changes such as morning-evening, rainy days and sunny days through the exterior window of the assembly production plant. In addition, since the material of the vehicle body parts is a steel sheet, the reflection of light is very severe, which causes a problem in that the quality of the captured image is greatly changed even with a small light change. In this study, the distance between the car body and the door part and the door are acquired by the measuring device combining the laser slit light source and the LED pattern light source. The result is transferred to the joint robot for assembling parts at the optimum position between parts, and the assembly is done at the optimal position by changing the angle and step.

Cognitive Discrepancies of the Mutual Development Strategies of Western and Oriental Medicine in Korea - A Comparison between Western and Oriental Medical Practitioners and Health Professionals - (양.한방 상호보완 방안에 관한 인식도 연구 - 의사, 한의사 및 보건의료전문가간 비교를 중심으로 -)

  • Park, Jong-Ku;Kim, Chun-Bae;Cho, Kyung-Sook;Choi, Seo-Young;Lee, Jong-Chan;Lee, Sun-Dong;Chun, Sae-Il;Kim, Joong-Ho
    • Health Policy and Management
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    • v.10 no.4
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    • pp.57-74
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    • 2000
  • This study is conducted to compare how the Western.Oriental medical practitioners and health professionals perceive reciprocal development strategies respectively of Western.Oriental Medicine in Korea. A total of 3,273 persons were questioned by direct distribution, e-mail, and mail with a self-developed questionnaire. Of those questioned, 362 responded (the response rate of 11.1%), and of them n persons (Western medical practitioners 206, Oriental medical practitioners 90, and health professionals 64) were analyzed with SPSS for Windows. The results were as follows: The need for legislation on the mutual development system for Western.Oriental Medicine was recognized by 66.9% (218 persons) of respondents. Among them, largest group who agreed with this need was the health professionals. Western medical practitioners chose the "the difference of approach methods on the diseases between Western.Oriental Medicine" as their response, and Oriental medical practitioners & health professionals selected "the indifference or bias of Western medical practitioners"as the reasons for the inactivity in developing a mutual system of Western.Oriental Medicine. Therefore, Western medical practitioners and health professionals selected the category of "the reformation of educational system", while Oriental medical practitioners selected the category of "the activation of joint research on Western.Oriental medical care" as the most important condition for setting a precedent. Also, Western medical practitioners preferred "cooperative health care system for Western medical care supported by Oriental medical care", but Oriental medical practitioners and health professionals preferred “cooperative health care system of Western.Oriental medicine on equal terms" In conclusion, Western '||'&'||' Oriental medical practitioners have to make every effort to close the gap between differing views through mutual understanding and respect if joint research of Western.Oriental medical care is to become a reality. The government should continuously enforce the health policy on development of a legal and systematic infrastructure for mutual development strategy of Western.Oriental Medicine in Korea.strategy of Western.Oriental Medicine in Korea.

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Study on the Extension of Reinforced Concrete Slabs (철근콘크리트 바닥판 평면확장 공법에 대한 연구)

  • Kim, Jin-Pyeng;Kim, Sang-Sik;Choi, Kwnag-Ho;Jeon, Byong-Gap;Lee, Jung-Yoon
    • Journal of the Korea Concrete Institute
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    • v.18 no.3 s.93
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    • pp.321-330
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    • 2006
  • In order to remodel old aged reinforced concrete buildings, it is often required to extend the residence area of the buildings by increasing the slab area. The slab area is usually extended by attaching a new slab to the existing slab with hinged joint or rigid joint. Transmission of the loads of the attached slabs to the existing slabs depends on the connecting methods, such as hinged or rigid connection. In this research, 8 specimens and 24 RC slabs connected by rigid joints were tested. The new slab was connected to the existing slab by three types of rigid joints using dowel bars and longitudinal tensile bars. Main parameters of the slabs were three types of the rigid joints, anchor length of steel bars(0, 50, 60, 100, and 120mm), development length of steel bars(100, 200, and 300mm), and the spacing of the steel bars(150, 200, 300, and 450mm). The test results indicated that the flexural strength of the RC test slabs having various types of rigid joints was approximately the same to that of the slab without any connections.

Flip Chip Process for RF Packages Using Joint Structures of Cu and Sn Bumps (Cu 범프와 Sn 범프의 접속구조를 이용한 RF 패키지용 플립칩 공정)

  • Choi, J.Y.;Kim, M.Y.;Lim, S.K.;Oh, T.S.
    • Journal of the Microelectronics and Packaging Society
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    • v.16 no.3
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    • pp.67-73
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    • 2009
  • Compared to the chip-bonding process utilizing solder bumps, flip chip process using Cu pillar bumps can accomplish fine-pitch interconnection without compromising stand-off height. Cu pillar bump technology is one of the most promising chip-mounting process for RF packages where large gap between a chip and a substrate is required in order to suppress the parasitic capacitance. In this study, Cu pillar bumps and Sn bumps were electroplated on a chip and a substrate, respectively, and were flip-chip bonded together. Contact resistance and chip shear force of the Cu pillar bump joints were measured with variation of the electroplated Sn-bump height. With increasing the Sn-bump height from 5 ${\mu}m$ to 30 ${\mu}m$, the contact resistance was improved from 31.7 $m{\Omega}$ to 13.8 $m{\Omega}$ and the chip shear force increased from 3.8 N to 6.8 N. On the contrary, the aspect ratio of the Cu pillar bump joint decreased from 1.3 to 0.9. Based on the variation behaviors of the contact resistance, the chip shear force, and the aspect ratio, the optimum height of the electroplated Sn bump could be thought as 20 ${\mu}m$.

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AUTOMATIC MULTITORCH WELDING SYSTEM WITH HIGH SPEED

  • Moon, H.S;Kim, J.S.;Jung, M.Y.;Kweon, H.J.;Kim, H.S.;Youn, J.G.
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.320-323
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    • 2002
  • This paper presents a new generation of system for pressure vessel and shipbuilding. Typical pressure vessel and ship building weld joint preparations are either traditional V, butt, fillet grooves or have narrow or semi narrow gap profiles. The fillet and U groove are prevalently used in heavy industries and shipbuilding to melt and join the parts. Since the wall thickness can be up to 6" or greater, welds must be made in many layers, each layer containing several passes. However, the welding time for the conventional processes such as SAW(Submerged Arc Welding) and FCAW(Flux Cored Arc Welding) can be many hours. Although SAW and FCAW are normally a mechanized process, pressure vessel and ship structures welding up to now have usually been controlled by a full time operator. The operator has typically been responsible for positioning each individual weld run, for setting weld process parameters, for maintaining flux and wire levels, for removing slag and so on. The aim of the system is to develop a high speed welding system with multitorch for increasing the production speed on the line and to remove the need for the operator so that the system can run automatically for the complete multi-torch multi-layer weld. To achieve this, a laser vision sensor, a rotating torch and an image processing algorithm have been made. Also, the multitorch welding system can be applicable for the fine grained steel because of the high welding speed and lower heat input compare to a conventional welding process.

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