• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.113-123
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• 2002

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.237-245
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• 1998

Greenhouse crop production under critical summer climate In Korea has considerable difficulties because of high temperature and relative humidity. In this study, some water pipes were tested as a means of the dehumidification and increment of evaporative cooling efficiency. As a result of heat transfer characteristic analysis, overall heat transfer coefficient of copper pipe was larger than steel pipe, and estimated values were smaller than measured values. The condensed quantities of vapor were not significantly different between copper pipe and steel pipe, however dehumidifying effect by the water pipes was significantly large. It was estimated based on the results that the evaporative cooling system by the water pipe will be able to increase the evaporative cooling efficiency of about 48%, and decrease the temperature of about 1.3$^{\circ}C$.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.118-123
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• 2000

This paper describes the characteristics of a newly suggested arc-inducing driven rod with needles which could effectively spread out both the failure current with power frequency and the lightning current. The structural characteristic of the driven rod was that needles were attached on the surface of the conventional shaped driven rod and the driven rod with needles was installed inside of a copper pipe.As a result of analyzing the characteristics of this suggested driven rod when it was employed as the driven rod of an arrester in distribution system, it was verified that the primary voltage of the arrester was reduced by effectively exhausting the electrical energy since the arc occurred between the needle and the copper pipe.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.1
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• pp.1-8
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• 2004

This study intend to make easy modification, even if there is a new job or structure change, by modularizing program and computerize and automation of production control management used in CIM. under the condition where manager control production on the job-site, for increasing connection with other operation and management on the computer by monitoring center computer, recognizing information by computer is needed, it is possible by converting transaction. So this study goal is to make delivery control and order control fast and accurate by finding dynamic history of machine and production information in enterprise without input production and quality information by themselves with quality information system. So production increase and quality improvement are possible by diminishing manager's and producer's work with the result of the study combining POP and CIM, after that, in e-business and m-business period that every enterprise must pass, customer satisfaction and sales promotion are possible with employee's computerizing minds. these study result also can knowledge process condition with theoretical class and have a power in finding a solution with foundation of theoretical knowledge.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.2001-2005
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• 2005

The tensile test is generally used to measure mechanical properties with conventional fracture test. This test is extremely certain method to measure Young's modulus, yield strength, tensile strength and so on. ASTM, by international standard, prescribes two classes of tensile tests in tubular products. One is method that specimens aren't done by any process with Tube-shape. The other is that specimens are made on process for C-shape. In this paper, we would like to present the new-shape specimens for the tensile test. The presented specimen's shape is that put two pieces of C-shape specimens together. Besides a load point and a support point are fixed like Tube-shape specimens. This shape of specimen has a difference that existing specimen is made on one-step process out this specimen is made on two-step process. This shape is considered that stress concentration phenomenon occurs at the reduced section if a specimen is made on one step process.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.2
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• pp.175-179
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• 2006

Welders are exposed to a number of hazards including metal fumes, toxic gases, electricity, heat, noise, and radiation such as ultraviolet and infrared light. We encountered a patient who developed non-cardiogenic pulmonary edema within a day after cutting copper pipe with an oxyethylene torch. The patient was a 26-year-old welder. He complained of dyspnea, generalized myalgia, and febrile sensation the following morning. The patient's chest X-ray and chest CT scan showed extensively distributed and ill-defined centrilobular nodules. Both his symptoms and chest X-ray abnormalities improved spontaneously. We attributed the patient's symptoms to non-cardiogenic pulmonary edema due to nitrogen dioxide, reasoning that: 1) the pipe consisted only of copper, according to material safety data sheet (MSDS); 2) a previous report in the literature demonstrated increased nitrogen dioxide levels under similar conditions; 3) the patient's clinical course and radiologic findings were very reminiscent of non-cardiogenic pulmonary edema following accidental exposure to nitrogen dioxide.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.558-564
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• 2021

The water purifier market has increased rapidly in recent years. The welding technology of the evaporator is a key component that determines the level of ice production and the cold water performance of an ice purifier. The finger type evaporator of an ice purifier can remove ice and is divided largely into an instant heat method and a hot gas method. In the hot gas type evaporator, particularly during the production process, the pinhole phenomenon inside the copper pipe and clogging problems occur intermittently when welding high-pressure pipes due to the high-temperature oxygen welding. Its use in a water purifier can cause a problem in that ice and cold water do not form, and repairs cannot be made on site. To solve this problem, in this study, a cap jig was applied to improve the welding defect of the hot gas evaporator. In addition, the oxygen welding flame size was adjusted so that the heat source could be well supplied to the cap jig, and the effectiveness was confirmed through a wave pressure test, a test, and a thermal shock test.