• International conference on construction engineering and project management
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• 2013.01a
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• pp.616-623
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• 2013

One of the oldest, most common engineering problems is measuring the dimensions of different objects and the distances between locations. In AEC/FM, related uses vary from large-scale applications such as measuring distances between cities to small-scale applications such as measuring the depth of a crack or the width of a welded joint. Within the last few years, advances in applying new technologies have prompted the development of new measuring devices such as ultrasound and laser-based measurers. Because of wide varieties in type, associated costs, and levels of accuracy, the selection of an optimal measuring technology is challenging for construction engineers and facility managers. To tackle this issue, we present an overview of various measuring technologies adopted by experts in the area of AEC/FM. As the next step, to evaluate the performance of these technologies, we select one indoor and one outdoor case and measure several dimensions using six categories of technologies: tapes, total stations, laser measurers, ultrasound devices, laser scanners, and image-based technologies. Then we evaluate the results according to various metrics such as accuracy, ease of use, operation time, associated costs, compare these results, and recommend optimal technologies for specific applications. The results also revealed that in most applications, computer vision-based technologies outperform traditional devices in terms of ease of use, associated costs, and accuracy.

• Educational Technology International
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• v.8 no.1
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• pp.57-69
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• 2007

The advantages of the Internet enable teachers in the world to break the communication barriers between their schools and collaborate with each other, giving them opportunities for richer educational practices than ever accomplished. I assume that collaborative learning like an international exchange naturally lead the students to acquire the knowledge to communicate with their peers using ICT skills. In this paper, two international exchange projects that have years of practice are reported, i.e., new types of collaborative education projects that the development of the Internet has enabled us to carry out. The international exchanges reported here have been possible because both students and teachers have effectively used the various functions of the Internet. To use English as a "common international communication language" is particularly important for the youth in Asia, and the students have come to realize the importance of English as a communication language through these projects. Also, since these practices are based on the infrastructure of the Internet, they have elucidated what kind of Internet use produces richer educational results .At the final stage of the exchanges, "joint presentation in English" is designed. Students communicate and collaborate over the network, and finally meet with each other and try to give a presentation as a product of their collaborative work. The files and scenes of their presentations are stored on the network and used as educational materials in Asia as well as models for the activities in the following years. We will report how to design international exchange education in this Internet age.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.4
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• pp.305-313
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• 2016

Movements of the lower limb are important for normal walking and smooth oscillation of the center of gravity. The ankle rotations such as dorsi-flexion, plantar-flexion, inversion and eversion allows the foot to accommodate to ground during level ground walking. Current below knee (B/K) prostheses are used for replacing amputated ankle, and make it possible for amputees to walk again. However, most of amputees with B/K prostheses often experience a loss of terrain adaptability as well as stability because of limited ankle rotation. This study is focused on the development of multi-rotational prosthetic foot for lower limb amputee. Our prosthesis is possible for amputees to easily walk in level ground by rotating ankle joint in sagittal plane and adapt to the abnormal terrain with ankle rotation in coronal plane. The resistance of ankle joint in the direction of dorsi/plantar-flexion can be manually regulated by hydraulic damper with controllable nozzle. Furthermore, double layered rubber induce the prosthesis adapt to irregular ground by tilting itself in direction of eversion and inversion. The experimental results highlights the potential that our prosthesis induce a normal gait for below knee amputee.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.327-332
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• 2023

On December 26, 2022, North Korea's drone provocation resumed for the first time in eight years. The threat covered not only the Seoul metropolitan area but also the no-fly zone for the presidential office's security, and the South Korean military's response to it is not appropriate, which is a major controversy. In the midst of this, problems caused by the prohibition of small drones' flight and illegal intrusion into restricted areas are increasing in Korea, and the threat is becoming a reality, such as being used for terrorist attacks abroad. In this paper, the concept of "Counter-Drone" and related technologies were considered for these drone threats, and implications were derived through domestic and overseas small drone threats, and the direction of development of the Counter-Drone system was presented. North Korea's drone threat is expected to be more diversified, massified, and advanced, resulting in bolder attacks and provocations. Therefore, the South Korean military should push for early powering of the integrated control system and the conter drone system, joint and military cooperation in response to the threat of small drones, and the ability to carry out joint operations between South Korea and the U.S.

• Journal of Advanced Navigation Technology
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• v.6 no.2
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• pp.138-150
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• 2002

This paper addresses the problem of combining adaptive polarization processing and space-time processing for further performance improvement of radar target detection in clutter and Jammer environments. Since the most straightforward cascade combinations have quite limited performance improvement potentials, we focus on the development of adaptive processing in the joint polarization-space-time domain. Unlike a direct extension of some existing space-time processing algorithms to the joint domain, the processing algorithm developed in this paper does not need a potentially costly polarization filter bank to cover the unknown target polarization parameter. The performance of the new algorithm is derived and evaluated in terms of the probability of detection and the probability of false alarm, and it is compared with other algorithms that do not utilize the polarization information or assume that the target polarization is known.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5419-5424
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• 2014

A weld scallop is a small quadrant or half circle type hole installed in the weld line cross area for easy welding operation. Many types of T-bars with a scallop can be welded in a block assembly stage in shipbuilding. The difficulties arise from the fact that scallops are to be filled by build-up welding after welding of the cross line is complete. In this study, a non-scallop block joint welding method was developed using special type CBM (ceramic backing material). The wedge shaped CBM was devised to insert a CBM into just the V groove of weld line cross area without weld scallop. A saw-toothed shape was adopted for easy cutting of the unnecessary part in the CBM fitting process. The applicability of the developed method was verified through welding experiments based on the yard welding conditions.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.2 s.43
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• pp.23-33
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• 2007

The growing environmental regulation governs the use of lead by RoHS, WEEE, and then. The electronic industry is moving to replace Pb-bearing solder with Pb-free solder. To use the Pb-free solder, microelectronic industry needs consequently the new reliability appraisal such as the packaging for high temperature process, various mechanical change caused by new solder, and the development of Pb-free sloder for long life of product. The evaluation of solder bar and mechanical properties of joint were performed compared with international standard, and new appraisal standard was established. The solderability and spread ability of Sn-0.7Cu solder material showed up to the standard. Shear test of solder joint using by the solder resulted that the shear strengths after thermal shock or after aging were not much lower than the shear strength of as-soldered and that they were also up to the standard.

• Journal of muscle and joint health
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• v.11 no.1
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• pp.18-30
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• 2004

Purpose: The purpose of this study was to identify the trend of research on the nursing research in the journal of rheumatology health and to suggest future perspective for nursing research. Method: In this study, we reviewed the contents of 131 researches published in this journal from its beginning year 1994 to year 2003. Result: In the 85.5% researches, type of the research subjects was patient. research that subject is patient' family was none. An analysis of the research design showed, non-experimental research was 67.2%, experimental research was 26.7%, qualitative research was 5.3%, triangulation research was only one. In the experimental design types of nursing intervention were movement intervention 38.4%, cognitive intervention 38.4%. and true experimental research was none. Among non-experimental researches, 93.2% was survey method, methodological research was two, concept analysis research was two, a-method was one. Conclusion: There has been a lack of qualitative research, true experimental research, research using vary nursing intervention. Further research need nursing intervention development that intervention can be use in actual nursing care area.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.5
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• pp.527-535
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• 2015

As a new technical approach, a hydraulic and magnetic clamp device was attempted to realize a magnetic clamp crane system that uses 8 simultaneously actuating individual hydraulic cylinders. Through this approach, a Sr type of ferritic permanent magnet ($SrO{\cdot}6Fe_2O_3$), not the previously employed electro-magnet, was utilized for the purpose of lifting and transporting the heavy weighted and oversized curved steel plates used for manufacturing the ships. This study is aimed at manufacturing and developing the hydraulic magnetic clamp prototype, which is composed of three main parts - the base frame, cylinder joint, and magnet joint - in order to safely transport such curved steel plates. Furthermore, this research was pursued to conduct a performance evaluation as to the prototype manufacture and acquire the planned quantity value and the development purpose items. The most significant item for a performance evaluation was estimated for the magnetic adhesive force (G) and in this process, a ferritic permanent magnet (Sr type) with 3700~4000 G of residual induction (Br) and 2640/2770 Oe of coercive force (Hc) was utilized. In addition, other relevant items such as hoist tension (kN), transportation time (sec), and the applied load (Kgf) exerted on the hydraulic cylinders were also evaluated in order to acquire the optimum quantity value. As a result of the evaluation, the relevant device turned out to be suitable for safely transporting the curved steel plates.

• Journal of Electrical Engineering and Technology
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• v.8 no.1
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• pp.90-96
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• 2013

As the need of electric motor is increased rapidly throughout our society, the various application fields are created and the service market called robot gets expanded as well as the existing industrial market. Out of those, the joint systems such as humanoid that is servo actuator for position control or all fields which require multi-degree of freedom (multi-DOF) require the development of innovative actuator. It is multi-DOF spherical motor that can replace the existing system in multi-DOF operating system. But, multi-DOF spherical motor that has been researched up to date is at the stage which is insufficient in performance or mechanical practicality yet. Thus, first of all the research results and limitation of the previously-researched guide frame-type spherical motors were analyzed and then the feature of double air-gap spherical motor which was devised to complement that was studied. The double air-gap multi-DOF spherical motor is very suitable spherical motor for system applying which requires the multi-DOF operation due to its simple structure that does not require other guide frame as well as performance improvement due to its special shape which has two air-gaps. So, the validity of the study was verified by designing and producing it with 3D-FEM through the exclusive jig for multi-DOF spherical motor.