• Transactions of the Korean hydrogen and new energy society
• /
• v.12 no.3
• /
• pp.169-176
• /
• 2001

The purpose of study is to obtain low-emission and high-efficiency in LPG engine with hydrogen enrichment. The test engine was named heavy-duty variable compression ratio single cylinder engine (VCSCE). The fuel supply system provides LPG/hydrogen mixtures based on same heating value. Various sensors such as crank shaft position sensor (CPS) and hall sensor supply spark timing data to ignition controller. Displacement of VCSCE is $1858.2cm^3$. VCSCE was runned 1400rpm with compression ratio 8. Spark timing was set MBT without knocking. Relative air-fuel ratio(${\lambda}$) of this work was varied between 0.76 and 1.5. As a result, i) Maximum thermal efficiency occurred at ${\lambda}$ value 1.0. It was shown that thermal efficiency was increased approximately 5% with hydrogen enrichment at same ${\lambda}$ value. ii) Engine-out carbon monoxide (CO) emissions were decreased at a great rate under LPG/hydrogen mixture fuelling. iii) Total hydrocarbon (THC) emission was much exhausted in rich zone, same as CO. But THC was exhausted a little bit more in lean zone. iv) Finally, engine-out oxides of nitrogen (NOx) was increased with ${\lambda}$ value 1.0 zone at a greater rate with hydrogen enrichment due to high adiabatic flame temperature.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.472-472
• /
• 2011

The capacitive coupled plasma (CCP) has been extensively used in the semiconductor industry because it has not only good uniformity, but also low electron temperature. But CCP source has some problems, such as difficulty in varying the ion bombardment energy separately, low plasma density, and high processing pressure, etc. In this reason, dual frequency CCP has been investigated with a separate substrate biasing to control the plasma parameters and to obtain high etch rate with high etch selectivity. Especially, in this study, we studied on the etching of $SiO_2$ by using the pulse-time modulation in the dual-frequency CCP source composed of 60 MHz/ 2 MHz rf power. By using the combination of high /low rf powers, the differences in the gas dissociation, plasma density, and etch characteristics were investigated. Also, as the size of the semiconductor device is decreased to nano-scale, the etching of contact hole which has nano-scale higher aspect ratio is required. For the nano-scale contact hole etching by using continuous plasma, several etch problems such as bowing, sidewall taper, twist, mask faceting, erosion, distortions etc. occurs. To resolve these problems, etching in low process pressure, more sidewall passivation by using fluorocarbon-based plasma with high carbon ratio, low temperature processing, charge effect breaking, power modulation are needed. Therefore, in this study, to resolve these problems, we used the pulse-time modulated dual-frequency CCP system. Pulse plasma is generated by periodical turning the RF power On and Off state. We measured the etch rate, etch selectivity and etch profile by using a step profilometer and SEM. Also the X-ray photoelectron spectroscopic analysis on the surfaces etched by different duty ratio conditions correlate with the results above.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2006.06b
• /
• pp.39-46
• /
• 2006

It is naturally to be expected that the stress of seafarers has some specific characters compared to other workers who are labouring on land. Because the physical rigors of working and living at sea has been endured as a part of job. The excessive stress caused by shipboard life, their jobs, can weaken the health status and court the work related accidents. Also it will be the immediate causes of marine accidents such as collision, sinking etc. In this paper, a questionnaire survey was undertaken to find out the approximate quantity and source of seafarer's occupational stress. And the heart rate of deck officers on duty was measured to develop a profile of correlation between the stress and the work.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.11
• /
• pp.4745-4750
• /
• 2011

A HIL(hardware-in-the-loop) system was established and the simulation was carried out to determine whether the system operates normally. The system consists of turbocharger test bench, HIL platform with real time S/W and DAQ, and engine model using Matlab/Simulink. In the simulation the supplied fuel rate is changed step-by-step from 1.8944 kg/h to 4.7360 kg/h. The change of air-fuel ratio is analyzed and observed whether the air-fuel ratio follow the target air-fuel ratio 32. When the supplied fuel rate is changed, the air-fuel ratio is converged to the target air-fuel ratio after about 20 seconds. And the vane duty ratio of turbine and the boost pressure of compressor are also changed properly. Therefore this HIL system can be used to develop the new turbocharger and improve the performance of the modified turbocharger.

• The Korean Journal of Emergency Medical Services
• /
• v.13 no.1
• /
• pp.19-33
• /
• 2009

Purpose : To check the legal relation between rescue team and patient as well as legal responsibility for patient's damage intentionally or erroneously caused by rescue member, a public official, in the performance of relevant job ; to prevent legal dispute over rescue team and to present program for fair settlement of dispute and equitable and feasible burden of damage. Method : First, the legal principle of Civil Law, Criminal Law and Administrative Law related to the theme of this research will be investigated around research by literature. Second, the case of dispute related to rescue team will be introduced. Result: 1. If 119 rescue members as a public official intentionally or erroneously cause damage to patient in the performance of job, they shall bear civil, criminal and administrative responsibility. They shall bear civil responsibility for indemnity for damage due to default or tort. The typical criminal responsibility includes accidental homicide arising out of duty, preparing falsified official document, dereliction of duty, etc. In the administrative side, the state is responsible for indemnity for peculiar status of the rescue member, public official. 2. Though raising civil petition or legal dispute over unsatisfactory rescue service may be reasonable to guarantee the right of nation, such action may cause stress to rescue member as well as may lead to mental shrinking and defensive attitude only to take the basic first aid treatment which has low possibility of mistake instead of active first aid treatment so as to avoid legal responsibility. 3. The program that may prevent legal dispute over 119 rescue team includes expansion of manpower specialized in first aid treatment, enhancement of education on legal environment, development and application of standard job guideline, formation of mutual trust with patient, detailed explanation, preparing and keeping minute record, improvement of the rescue members' ability of first aid treatment and development of medical instruction mode. Conclusion : The best policy is to prevent legal dispute. If it is impossible to basically exclude the possibility of dispute, however, we need to make effort to minimize the occurrence, settle fairly and divide damage equitably and feasibly. To improve the preventible death rate of our first aid system to the level of advanced country, 119 rescue team which is in charge of the stage before hospital needs to positively enforce special first aid by improving the qualitative level of rescue service and to strive to prevent legal dispute that may occur in the process.

• The Korean Society of Law and Medicine
• /
• v.22 no.2
• /
• pp.3-48
• /
• 2021

Among the major rulings handed down in 2020, there were cases involving anaphylaxis, which is timely as a side effect of coronavirus and flu vaccine. And as a rare case, a ruling was handed down that if medical treatment was done so unfaithfully beyond the limit of patience of ordinary people, it can be an independent illegal act and a cause of compensation for emotional distress. Also, there was a ruling in the appellate court that evaluated disability rate applying the Korean Academy of Medical Sciences Guides for the Evaluation of Permanent Impairment, not McBride system. And the supreme court made it clear that telemedicine is illegitimate. In relation to duty of explanation, it is in the process of adding detail criterion on the firm principles in the individual cases. In regard of medical records, there was a case that even when a medical record is strongly suspected to be tampered with, it is not considered to be an obstruction of proof. There were cases that resulted in different conclusion between the court of first instance and the appellate court rulings. Lastly, in the face of a growing number of cases in which doctors are sentenced to prison for malpractice, we reviewed a ruling that sentenced a doctor to prison.

• Journal of Korean society of Dental Hygiene
• /
• v.1 no.2
• /
• pp.201-211
• /
• 2001

Dental caries causes the majority of tooth loss among Koreans. Korea is experiencing an increase in dental caries. And it shows a high prevalence of caries in preschool children, which contrasted with the much-improved situation in developed countries. So, it is important to control caries from preschool periods in Korea. Recently, inspections of the teeth of preschool children for evidence of dental disease became a legislative duty in Korea following Oral Health Act(2000). But, standardized oral health programs in preschool children is not yet proposed. Therefore, it is necessary to develop an community based oral health program in preschool children. The purpose of this study was to obtain basic data for the development of community based oral health program in preschool children of Sungnam city. Oral health status in primary dentition were surveyed in 862 2-6 year-old preschool children of Sungnam city by WHO criteria. From the data, df rate, percentage of preschool child ren with active caries, dft index, dt rate, percentage of preschool children with pit and fissure sealant of each age were calculated, and discussed. The obtained results were as follows : 1. The experience of dental caries in primary dentition showed a tendency to increase quickly between 2 and 3 year old children. So, the oral health program in preschool children should be developed to prevent dental caries and control their oral health under three years of age. 2. In 5 year-old children, the percentage with active caries was 60.8% and dft index was 5.06. The dt rate showed a tendency to decrease as proportion to age, but even though 6 year-old children, the dt rate was 47.7%. Therefore, the annual screening dental examination and oral health education programs at the institution for preschool children should be developed to detect and treat dental caries in primary dentition at early stage. 3. The percentage of preschool children with pit and fissure sealant at six years of age was 10.2%. So, pit and fissure sealant and professional fluoride application programs in Public Health Center should be developed to prevent dental caries. 4. Also, it is necessary to establish oral health goals in preschool children and develop water fluoridation program 10 improve and preserve oral health of preschool children in Seongnam city, effectively.

• Journal of agricultural medicine and community health
• /
• v.14 no.1
• /
• pp.30-36
• /
• 1989

In order to desirable attitudes of health subcenter personnel, affecting to utilization of a rural health subcenter for primary health care, a study carried out, through analyzing the specific survey datas of 228 out of 1151 total house-holders in a rural community, Su-Dong Myun, Yam-yang-ju kun, Kyung-Gi Do in Korea, and the medical re-cords of total out-patients of health subcenter in this district during 1981-1988. The following results were obtained: 1) The annual utilization rate showed decreasing tedency such as 723 per 1,000 inhabitants in 1981, 652 in 1982, 618 in 1985, 54H in 1984 and 341 in 1987, since 1981. 2) The utilization Rate in 1987 was unusually the lowest with 341 per 1,000 inhabitants in decreasing tendency, steadily. 3) In advatage on utilization of health subcenter for primary health care in a rural area, 68.8% of the respondents answered that it was in comprehensive health care with the highest rate and next order in near distance from living place with 16.7% in easy and simple process to utilize with 9.2% and in lower medical cost with 5.3%. 4) The order of desirable image of rural health subcenter personnel for primary health care was of good attitude(57.0%), of good skill(29.0 %) and of wide knowledge(14.0%), 5) The order of desirable image of doctor for primary health care in rural health subcenter was of good skill(.44.3%), of good attitude(36.8%) and of wide knowledge(18.9%), and nurse was of good attitude(76.8%), of good skill(14.0 %) and of wide knowledge(9.2%). 6) The percentage order by good attitudes of rural health subcenter personnel was the highest in responsibility(38.2%), kindness(26.3% ), proprieties(14.9%), sincerity(12.7%) and notion of duty hours(6.6%). 7) The statistical datas in health subcenter was written and kept, without distinction of definition of new and old patients, by month and for suitable method of medical expenses of medical insurance and medicaid by clerical convenience. 8) In future, the organization of health subcenter must be unified, systematized and rationlized for primary health care. Health subcenter must be organized by 3 parts of function(medical care, health service and clerical affair) and then function of health subcenter will be more activated by clerical activities.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.3
• /
• pp.112-118
• /
• 2018

In order to meet the strict emission regulations for internal combustion engines based on fossil fuel, the proportion of after-treatments for vehicles and vessels is gradually increasing. Diesel engines have high power, good fuel economy, and lower $CO_2$ emissions, and their market shares are increasing in commercial vehicles and passenger cars. However, NOx is generated in the localized high-temperature combustion regions, and particulate matter is formed in the zones of diffusion combustion. LNT and urea-SCR catalysts have been developed for after-treatment of the exhaust gas to reduce NOx in diesel vehicles. This study aims to improve the NOx reduction performance of Cu SCR catalyst, which is widely used in light, medium, and heavy-duty diesel engines. The de-NOx performance of $5Cu-2ZrO_2$/93Zeolyst(Si/Al=13.7) SCR catalyst was about 5-50% higher than that of $5Cu-2ZrO_2$/93Zeolite(Si/Al=2.9) at catalyst temperatures of $300^{\circ}C$ or higher. The zeolite had lower metal dispersion than zeolyst, and the reaction rate of the catalyst decreased as the average particle size increased. The $10Cu-2ZrO_2$/88Zeolyst catalyst loaded with 10wt% Cu had the highest NOx conversion rate of 40% at $200^{\circ}C$ and about 65% at $350^{\circ}C$. The ion exchange rate of Cu ions increased with that of Al, the crystalline compound of zeolite, and the de-NOx performance was improved by 20-40% compared to other catalysts.

• Journal of agricultural medicine and community health
• /
• v.20 no.1
• /
• pp.51-60
• /
• 1995

This study was to examine the awareness of health and the utilization of primary health care in rural areas. The data were obtained from self-administered questionnaire conducted 450 parents of Mi Gum md Su Dong middle school students in Nam yang Ju city, Kyung Gi-Do, Korea, from December 15 to 20 in 1993. The results were as follows : 1) Among the causes of disease, 'insufficient health care' was the highest(39.1%), and 'bad environment'(28.9%), 'complexity of life style'(17.8%) in next order. 2) In the priority between 'daily farm work' and 'primary health care', only 45.6% of respondents answered that primary health care is more important than the daily farm work. The 29.8% of respondents answered 'daily farm work', and the 23.1% answered 'the equal of the both'. 3) The 63.6% of the respondents recognized correctly, the meaning of primary health care. And the rate of information source in primary health care were 'TV and Radio'(42.2%), 'medical facilities'(23.3%), and 'newspaper and magazine'(11.3%) in order. 4) In the choice rate of medical facilities for primary health care, 'drug store' was the highest(34.9%), and 'local private clinic'(34.7%), 'health (sub)center'(15.8%), 'hospital'(10.2%) in next order. 5) The 53.5% of the respondents had experienced to visit the health (sub)center more than once. And the disfavorite reasons of health (sub)center were 'insufficient equipment'(36.7%), 'inavailable time to visit'(26.9%), and 'poor treatment'(9.1%). 6) Among the preference of the physicians for primary health care, 'specialist' was the highest rate of the respondents(54.2%), and 'general practitioner'(32.4%), and 'family doctor'(9.8%) in next order. The major obstacles in utilizing the medical facilities for primary health care were 'daily farm work'(41.6%), 'distance'(21.1%) and 'medical cost'(10.4%) in order. 7) The weakened reasons in health (sub)center function were 'insufficient medical equipment'(44.4%), 'the lack of resident's understanding for health (sub)center'(21.8%), and 'short thought of duty in health (sub)center personnel'(16.9%) in order.