• Journal of ILASS-Korea
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• v.18 no.3
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• pp.132-139
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• 2013

Smoke emissions from light duty diesel vehicles were measured using light extinction method with the free acceleration test mode. The smoke emissions for each measurement cycle of the free acceleration method showed large variations according to driver's pedal pushing pattern. The smoke values for each measurement cycle initially increased and reach a peak value. Integration of the smoke emissions with time for each measurement cycle was performed to get a representative smoke value which was obtained by averaging the integrated results. Two kinds of integration time range were used. One is range over the whole measurement cycle of the free acceleration method. The other is only the acceleration range in the measurement cycle. Overall, variation of the representative smoke values obtained by the integration method was reduced comparing to the traditional representative smoke value which was obtained from a peak smoke value over the measurement cycle. Ten vehicles of the same model with 2.5 liter diesel engines, and seven vehicles of the same model with 2.7 liter diesel engines, were tested using the free acceleration test method.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.4
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• pp.353-360
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• 2008

The LGP with nanometer structures resulted in enhancement of optical efficiency. Its fundamental mechanism is to recycle the polarized light via one round-trip through QWP(Quarter-Wave Plate) but the maximum efficiency to reach with this method is limited up to 2. To get the larger efficiency than this limited one a LGP with nanometer-patterned grating is suggested. For its optimum design the computer simulation is performed and suggests a grating that the spatial frequency between adjacent patterns is 500nm, its height 250nm, duty cycle 50%, and its cross section is rectangular. On the basis of simulation results the LGP with nanometer-patterned grating is fabricated and its optical properties such as angular intensity distribution and CIE color coordinates are characterized. The angles of transmitted light are nearly the same as the results expected from the generalized Snell's law. Thus the Mathematica code, developed in this experiment, will be applied to designing the optimized LGP. The LGP with nanometer-patterened grating shows the enhancement of transmitted intensity distribution up to 4.9 times.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.3
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• pp.47-55
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• 2010

Investigations on the inundation damage and improvement measures were carried out centering around the protected horticultural complex concentrated in lowlands on the side of Geum river, in Nonsan and Buyeo, Chungnam. Most greenhouses were single-span plastic houses in this area, and tomato, strawberry and watermelon were cultivated mainly. 45.8 % of whole farmhouse were experienced in damage by inundation, and a frequency of the damage was average once in 11 years. The most urgent problem at the greenhouse culture in this area was showed in order of drainage improvement, irrigation water resources and energy saving. Consideration items in drainage improvement project for protected horticulture were showed in order of extending drain pumps, extending drain canals, using concrete flume in drain ditch. It needs to consider systematic plans that can restrain new establishment of greenhouses on the lowland paddy field in drainage area. It is difficult to remove greenhouses which are already established or prohibit cultivation. Therefore we should impose minimum duty items so that greenhouse tillers can cope with inundation. And it is thought that managing agency need to minimize farmers damage by improving drainage ability and introducing maintenance pattern that is different from rice cropping.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.6
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• pp.530-534
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• 2008

The LGP with nanometer structures resulted in enhancement of optical efficiency. Its fundamental mechanism is to recycle the polarized light via one round-trip through QWP(Quarter-wave Plate) but the maximum efficiency to reach with this method is limited up to 2. To get the larger efficiency than this a LGP with 1D PC(one-dimensional photonic crystal) nanometer-patterned on its top and bottom surfaces is suggested. For its optimum design the computer simulation is performed and suggests a grating that the spatial frequency between adjacent patterns is 500nm, its height 250nm, duty cycle 50%, and its cross section is rectangular. The angles of transmitted light are nearly the same as the results expected from the generalized Snell's law. Thus the Mathematica code, developed in this experiment, will be applied to designing the optimized LGP. The LGP with nanometer-patterened 1D PC LGP on its both surfaces shows the enhancement of transmitted intensity distribution up to 5.7 times.

• Journal of ILASS-Korea
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• v.21 no.3
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• pp.137-143
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• 2016

The LPG vehicles are being operated by commercial purposes generally such as taxis. Most of taxis have a long-mileage and a harsh driving pattern. These properties may accelerate aging of the three-way catalysts much faster than the passenger vehicles. Because of this background, it was analyzed the test result of fuel efficiency and emissions on the LPG-fueled light duty vehicle. It was selected for a LPG vehicle of ULEV level to measure the fuel efficiency and emissions of the aged three-way catalysts. And the aged three-way catalysts which was driven about 300,000km and 550,000km replaced on the test vehicle in consecutive order. As a result, The aged three-way catalysts generally had no effect on fuel efficiency result, and harmful exhaust emissions had been shown to increase in most of the test mode, even though it satisfied the regulation value on most test modes.

• Transactions of Materials Processing
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• v.21 no.1
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• pp.67-74
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• 2012

Although high productivity is possible, cold forged helical gears have not been widely used due to difficulty in achieving mechanical properties as well as dimensional accuracy of the product. Confidence in the gear characteristics also is very important in heavy-duty gear applications. Therefore, the properties of forged gears must be compared to the properties of conventional machined gears. The properties might be different due to the different fabrication processes. In this study, machined and forged products both before and after heat-treated have been compared by measuring the residual stress and involute curve of the tooth. Characteristics of hardness and microstructure were also compared. Additionally, tooth fracture strength was compared for the heat-treated products. Moreover, the tooth strength and the fracture pattern were compared between the machined and forged gears. The forged gear showed decreased changes in residual stress and decreased changes in dimensions when compared to the machined gear before and after heat treatment. The forged gear was over 10% better than the machined gear in tooth strength.

• Journal of Institute of Convergence Technology
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• v.11 no.1
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• pp.19-23
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• 2021

These days, sales of battery electric vehicles have been rapidly increasing due to the strict CO₂ regulations. However, since it take too long to measure the energy economy of electric vehicles, it has been required to improve the procedure of energy economy measurement. In order to improve this problem, the present study analyzed the battery charge/discharge pattern according to the changes in battery SOC (state of charge). In general, the energy economy test is started with a battery SOC charged to 100 %. However, it was identified that when the battery is fully charged, it can actually be charged over the 100 % (e.g., 100.5 %). This can induce errors in the energy economy measurement. Therefore, the present study recommend to start the test at SOC 99.9 %. The regenerative braking was partly restricted for the SOC over 90 %. This made it difficult to estimate the overall energy economy of the electric vehicle. However, it was identified that there was no change in the battery charge/discharge characteristics under the SOC 90 %. Therefore, the energy economy test can be shortened by predicting the overall energy economy through a short mileage test.

• Korean Journal of Adult Nursing
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• v.13 no.1
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• pp.123-135
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• 2001

The purpose of this study is to analyze the structural pattern of nurses' pain management with patients who experience pain. As a research method, the Q methodology, which is useful for an objective view of a highly abstract concept, was applied. The data collecting activity of this study was from August, 21st, 2000 to November, 24th 2000. The Q-population, the previous thesis and a literature review were done. Questions about pain management by the nurse on the patients, caregivers, nursing students, doctors, nurses, and others were asked in documentary work and in-depth interviews. In all, 223 units of the Q-population were formed, and the last 35 units of the Q-population were extracted. The data on the P-sample was collected from 41 nurses who worked in the medical and surgical units of a hospital that belonges to C university in Seoul. The research results were constituted in 3 types. Type I was the 'pattern of judging by objectivity'. The statement on which most of the people highly agreed for those patterns was shown by 'If patients said that they are suffering from pain, we sufficiently performed an assessment about the etiology, location, duration and degree'. For type I, the same pain was found in different locations according to the patients, so the etiology of the pain should be identified first place. Since ways of coping are different according to pain etiology, it was thought that it is important to assess sufficiently the pain etiology, location, duration, and degree. Therefore, when patients complain of pain, the pain etiology should be identified and assessed; according to the result, pain management should be performed systematically. Type II was the 'pattern of accepting by subjectivity'. The statement on which most of the people highly agreed for those patterns was shown as 'If patients said that they are suffering from pain, the medical treatment should be performed rapidly and speedily.' For type II, when the patient complains of pain, treatment should be performed quickly in order to prevent the condition getting worse, and it is thought that activity is a reasonable duty. Further, by trying to show empathy after pain is admitted and by understanding and coping rapidly with the pain of patients, an attitude which matched the altruistic morals of nurses is being shown. Type III was the 'pattern of worrying about', and the statement on which most of the people highly agreed for those patterns was shown is 'When there is a pain, to help patients to tolerate the pain to the highest degree.' In type III, the pain is a subjective expression, so there is a difference according to every individual. Therefore, actually if there is no measurement of pain, it could be exaggerated so nurses should help patients to tolerate it to the utmost. Even if there is a way to remove pain without an analgesic drug, nurses were reluctant to perform pain management as they possibly could. Through these research results, pain management of nurses was classified in 3 types, and structural characteristics in each type were discovered. Based upon the characteristics according to the type, an individualized pain management intervention strategy should be established and the follow up work performed.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.4
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• pp.407-413
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• 2011

This paper presents an electrical power monitoring system for home energy management and an automatic appliance-identification algorithm based on the electricity-usage patterns collected during the monitoring tests. This paper also discusses the results of the field tests of which the proposed system was voluntarily deployed at 13 homes. The proposed monitoring system periodically measures the amount of power consumption of each appliance with a pre-specified time interval and effectively displays the essential information provided by the monitored data which is required users to know in order to save power consumption. Regarding the field tests of the monitoring system, the households responded that the system was useful in saving electricity and especially the electricity-usage patterns per appliances. They also considered that the predicted amount of the monthly power consumption was effective. The proposed appliance-identification algorithm uses 4 patterns: Zero-Crossing Rate(ZC), Variation of On State(VO), Slope of On State(SO) and Duty Cycle(DC), which are applied over the 2 hour interval with 25% of it on state, and it yielded 82.1% of success rate in identifying 5 kinds of appliances: refrigerator, TV, electric rice-cooker, kimchi-refrigerator and washing machine.

• Korea journal of population studies
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• v.25 no.1
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• pp.83-111
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• 2002

This study examines the structure of intergenerational relationship and its effects on old-age security of the Korean society. Of interest is the effects of the middle aged's attitudes on old parents'security on their intergenerational exchange relationship and on their own old-age security as well. This study also attempts to test the applicability of the social exchange perspective to the study of intergenerational support relationship in Korea The social exchange perspective considers intergenerational relationship as an exchange of aids and rewards between generations. However due to strong norm of filial duty and inadequate welfare system, supporting old parents is regarded as younger generation's duty in Korea This study utilizes a survey data conducted by Kim et al.(2000). Major findings can be summarized as follows. First, the middle aged who gives one-sided supports to their parents tends to have the traditional attitude on old parents' security. It implies that intergenerational support relationship in Korea is not consistent with the explanations from the social exchange perspective. This study suggests a 'chained reward system'as an altermative explaining the intergenerational relationship. Second, an absolute majority of the middle aged tend to think that they are responsible for their own old-age security regardless of the pattern of intergenerational support relationship and attitudes on old parents' security. It implies that the middle aged in Korea holds the status of 'marginal men' who supports their parents but can't take the similar supports from their children.