• Economic and Environmental Geology
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• v.5 no.4
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• pp.187-209
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• 1972

Drilling position is one of the most important factors affecting on the blasting effects. There has been many reports on several blasting factors of burn-cut by Messrs. Brown and Cook, but in this study the author tried to compare drilling positions of burn-cut to pyramid-cut, and also to correlate burn-cut effects of drilling patterns, not being dealt by Prof. Ito in his theory, which emphasized on dynamical stress analysis between explosion and free face. According to former theories, there break out additional tensile stress reflected at the free face supplemented to primary compressive stress on the blasting with one-free-face. But with these experimented new drilling patterns of burn-cut, more free faces and nearer distance of each drilling holes make blasting effects greater than any other methods. To promote the above explosive effect rationary, it has to be considered two important categories under-mentioned. First, unloaded hole in the key holes should be drilled in wider diameter possibly so that it breaks out greater stress relief. Second, key holes possibly should have closer distances each other to result clean blasting. These two important factors derived from experiments with, theories of that the larger the dia of the unloaded hole, it can be allowed wider secondary free faces and closes distances of each holes make more developed stress relief, between loaded and unloaded holes. It was suggested that most ideal distance between holes is about 4 clearance in U. S. A., but the author, according to the experiments, it results that the less distance allow, the more effective blasting with increased broken rock volume and longer drifted length can be accomplished. Developed large hole burn-cut method aimed to increase drifting length technically under the above considerations, and progressive success resulted to achieve maximum 7 blasting cycles per day with 3.1m drifting length per cycle. This achievement originated high-speed-drifting works, and it was also proven that application of Metallic AN-FO on large hole burn-cut method overcomes resistance of one-free-face. AN-FO which was favored with low price and safety handling is the mixture of the fertilizer or industrial Ammonium-Nitrate and fuel oil, and it is also experienced that it shows insensible property before the initiation, but once it is initiated by the booster, it has equal explosive power of Ammonium Nitrate Explosives (ANE). There was many reports about AN-FO. On AN-FO mixing ratio, according to these experiments, prowdered AN-FO, 93.5 : 6.5 and prilled AN-FO 94 : 6, are the best ratios. Detonation, shock, and friction sensities are all more insensitive than any other explosives. Residual gas is not toxic, too. On initation and propagation of the detonation test, prilled AN-FO is more effective than powered AN-FO. AN-FO has the best explosion power at 7 days elapsed after it has mixed. While AN-FO was used at open pit in past years prior to other conditions, the author developed new improved explosives, Metallic AN-FO and Underwater explosive, based on the experiments of these fundmental characteristics by study on its usage utilizing AN-FO. Metallic AN-FO is the mixture of AN-FO and Al, Fe-Si powder, and Underwater explosive is made from usual explosive and AN-FO. The explanations about them are described in the other paper. In this study, it is confirmed that the blasting effects of utilizing AN-FO explosives are very good.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1277-1283
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• 1998

Background : Surgical tracheostomy(ST) is usually performed by surgeons in operating room. For a patient with mechanical ventilation, however, transportation to operating room for ST could be dangerous for patients. In addition, ST is often delayed due to unavailability of operating room or surgeon. Percutaneous dilatational tracheostomy(PDT), although novel in Korea, is gaining popularity as a bedside procedure in the hospitals of western countries. We evaluated the technical ease and safety of PDT in comparison with ST. Method : Thirty-eight patients in medical intensive care unit (ICU) who were either under mechanical ventilation for more than 7 days or required airway protection, were randomly assigned to ST(18 patients) or PDT(20 patients). Between two groups, there was no significant clinical difference except that female to male ratio was higher in the ST group. ST was performed by second year residents of the department of otolaryngology while PDT was performed by third grade medical resident and pulmonologist under bronchoscopic guide using Ciaglia Percutaneous Tracheostomy Set(Cook Critical Care, Bloomington, USA) in medical ICU. The following factors were compared between two groups : number of delayed cases after the decision for tracheostomy, procedural time, complications related to tracheostomy. Results : Delayed cases were 11 in ST group and 3 in PDT group (P<0.05). Procedural time was significantly shorter in PDT group ($15.6{\pm}7.1min$) than in ST group ($29.1{\pm}11.6min$, P<0.0001). Complications related to tracheostomy occurred in 5 cases in ST group : accidental decannulation (1), subcutaneous emphysema (2) and minor bleeding (2), and in 4 cases in PDT group : minor bleeding (2), subcutaneous emphysema (1) and premature extubation (1) (P>0.05). Conclusion : Since percutaneous dilatational tracheostomy was easy to practice and its complications were not different from surgical tracheostomy, PDT can be a useful bedside procedure for mechanically ventilated patients.

• Journal of radiological science and technology
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• v.44 no.5
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• pp.525-534
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• 2021

In order to provide high-quality medical services to the public and contribute to the improvement of public health, it is necessary to enact an independent law according to the work of radiological technologists. Therefore, this study intends to review the regulations related to radiographers in the Medical Service Technologists, etc. Act. and to present opinions and directions for enactment of individual laws for radiological technologists. An online survey was conducted to 15,000 radiological technologists working in medical institutions and education sites in Korea; 1,027 people (6.85%) responded. The questionnaire consisted of 3 questions on demographic characteristics, 5 questions on the scope of work, and 12 questions on the revision of the Medical Service Technologists, etc. Act. and the establishment of the Radiological Technologist Independent Act. Reliability and factor analysis were performed on 9 questions measured on a Likert 5-point scale in "Revision of the Medical Service Technologists, etc. Act. and the establishment of the Radiological echnologist Independent Act" among the questionnaire items. Reliability for the total 9 questions was Chronbach α=0.728. There was a high perception that the regulations related to radiological technologists were insufficient in the current Medical Service Technologists, etc. Act., and the perception that examinations performed by radiological technologists at medical institutions were included in medical practice was high. If the Radiological Technologist Independent Act is enforced, a high percentage of respondents said that they could receive legal protection through the institutionalization of the scope of work, that the status of radiological technologists would be improved, and the scope of work would be expanded. The response that the scope of work of radiological technologists should be included was the highest at 96.6%. In the analysis according to demographic characteristics, it was found that 96.7% of the respondents were agreed regardless of the factors. Radiological technologists will have to work hard to secure the public health by coping with new radiology devices, procedures and treatment methods. Therefore, as the results of this study, it is expected that the enactment and implementation of the Radiological Technologist Independent Act will contribute to the improvement of the quality of treatment for patients and to the public health.

• Research in Community and Public Health Nursing
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• v.9 no.2
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• pp.502-517
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• 1998

This research intends to survey family environment, health behavior and health status of the students in urban-rural elementary schools and analyze those factors comparatively, and use the result as basic material for school health teacher to teach health education in connection with family and regional areas. It also intends to improve a pupil's self-abilitiy in health care. The subjects involve 2,774 students of urban elementary schools and 583 student in rural ones, who were selected by means of a multi -stage probability sampling. Using the questionnaire and school documents, we collected data on family environment, health behavior and health status for 19 days. Feb. 2nd 1998 through Feb. 20th 1998. The R -form of Family Environment Scale (Moos, 1974) was used in the analysis of family environment(Cronbach's Alpha =0.80). Questionnaires of Health Behavior in School-aged children used by the WHO in Europe(Aaro et al., 1986) and the ones developed by the Health Promotion Committee of the Western Pacific(WHO, 1995)(adapted by long Young-suk and Moon Young-hee(1996)) were used in the analysis of health behavior, as well documents on absences due to sickness, school health room-visits, levels of physical strength, height, weight and degree of obesity were used to determine health status. In next step, We used them with an $X^2$-test, t-test, Odds Ratio, and a 95% Confidence Interval. 1. In two dimensions of three, family-relationship (t=3.41, p=0.001) and system -maintenances(t= 2.41, p=0.0l6) the mean score of urban children were significantly higher than those of rural ones. In the personal development dimension however, there was little significant difference. Assorting family environment into 10 sub-fields and analyzing them, we recognized that urban children were superior to rural children in the sub-fields of expressiveness (t =3.47, p=0.001), conflict (t=0.48, p=0.001), active-recreational orientation (t = 1.97, p=0.049) and organization (t=4.33, p=0.000). 2. Referring to the Odds Ratios of urban-rural children's health behaviors, urban children set up more desirable behavior than rural children wear ing safety belts (Odds Ratio =0.32, p=0.000), washing hands after meals(Odds Ratio = 0.43, p= 0.000), washing hands after excreting (Odds Ratio = 0.39, p=O.OOO), washing hands after coming - home ( Odds Ratio = 0.75, p = 0.003), brushing teeth before sleeping(Odds Ratio =0.45, p=0.000), brushing teeth more than once a day (Odds Ratio =0.73, p=0.0l2), drinking boiled water (Odds Ratio = 0.49, p=0.000), collecting garbage at home(Odds Ratio=0.31, p=0.000) and in the school(Odds Ratio =0. 67, p=0.000). All these led to significant differences. As to taking milk(Odds Ratio = 1.50, p=0.000), taking care of eyesight(Odds Ratio=1.41, p=0.001) and getting physical exercise in(Odds Ratio = 1.33, p=0.0l9) and outside the school(Odds Ratio = 1.32, p=0.005), rural children had more desirable behavior which also revealed a significant difference. There was little significant difference in smoking, but the smoking rate of rural children(5.5%) was larger than that of urban children(3.9%). 3. Health status was analyzed in terms of absences, school health room-visits, levels of physical strength, and the degree of obesity, height and weight. Considering Odds Ratios of the health status of urban-rural children, the health status of rural children was significantly better than that of the urban ones in the level of physical strength(t=1.51, p=0.000) and the degree of obesity(t=1.84, p=0.000). The mean height of urban children ($150.4{\pm}7.5cm$) is taller than that of their counterparts($149.5{\pm}7.9$), which revealed a significant difference (t =2.47, p=0.0l4). The mean weight of urban children($42.9{\pm}8.6kg$) is larger than that of their counterparts($41.8{\pm}9.0kg$), which was also a significant difference(t=2.81, p=0.005). Considering the results above, we can recognize that there are significant differences in family environment, health behavior, and health status in urban-rural children. These results also suggestion ideas for health education. What we would suggest for the health program of elementary schools is that school health teachers should play an active role in promoting the need and importance of health education, develop the appropriate programs which correspond to the regional characteristics, and incorporate them into schools to improve children's ability to manage their own health management.

• Journal of Korean Academy of Nursing
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• v.11 no.2
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• pp.33-54
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• 1981

The purposes of this study were to determine the relevant nursing needs of patients following discharge; to identify the degree of their nursing needs; to identify types and status of discharge order and information given to patients; and to determine their specific nursing needs according to their diagnosis. In addition, opinions toward home care services provided by hospitals or by public health nurses and appointment plans with their physicians were also asked in order to determine the necessity of follow-up care for the patient after discharge. Nine hundred and eighty eight subjects were collected among patients being discharged from one national university hospital and four city hospitals. Data were collected from June,1979 to December,1979 using questionnaires and interviews. On the bases of these data the following findings were observed; 1) Almost 40 percents of total subjects discharged from the hospital with some or great degree of nursing needs in general. The most problematic nursing needs were needs for comfort which include needs for releaving pain, for sound sleep and rest, because these needs can only be met by professional help. More than 50% of total subjects have this problem. 2) Needs for mental health, general metabolism, general hygiene and activities and safety were observed in more than 20 percent of subjects. 3) Discharge orders on diet and oral medication were recorded in patients' charts in 70% of all cases. However, more than fifty percents of patients have not been told these information from doctors or nurses. Even though some of them might have had appointment plans with their physicians, they would not keep the appointments unless they completely understood the necessity of the follow-up care. If they have not had any appointment or would not visit the out-patient clinic, there is no method of caring them and prerenting funther discomfort or complications. Even in injection, ski care, dressing and bath, only one thirds of the subjects having recorded discharge orders understood what they need after discharge. The rest of cases have not known what to do for their further care. 4) More than 80 percents and 70 percents of total subjects agreed to a system of home care services provided by hospitals or public health nurses respectively. That is, regardless of sources of medical expenses, most of patients wanted to be taken care of at home following discharge. 5) While more than half of the patients having benefit of medical insurance or paying fully by themselves had appointment plans with their physicians, only one thirds of the patients fully or partially paid by government had appointment plans with their physicians. These results ex-plain that the appointment plan is directly associated with their economic power. This indicates that the home care services are more needed to the people with lower economical status. 6) Those who have been in the hospital more than 24 days wanted !o have home care services more than those who had less hospital days. They also had more appointment plans than other groups. 7) More than 70 percents of the subjects who had been in a university hospital and approximately 30 percents of the subjects in the city hospitals had appointment plans with their physicians. 8) Those who had the cerebrovascular disease, cancer or hypertension demanded more nursing needs such as needs for comfort, for general metabolism and for mental health. 9) Factors which were associated with the degree of patients' nursing needs were age, duration of hospitalization, opinion toward home care services given by public health nurses, hospital appointments and types of hospital. That is, the older they were and the longer the periods of hospitalization were, the higher were their nursing needs. The more they had nursing needs, the more they wanted to have nursing services and had appointment plans. It can be concluded that there is a great demand for a positive and systematic home care services to the people who have been discharged from hospitals following critical care. This program is definitely demanded for the low income groups of people with less education with the financial assistance of the government or other funding agencies.

• Korean Journal of Heritage: History & Science
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• v.52 no.2
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• pp.240-253
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• 2019

Archaeological heritages are precious cultural relics and public assets that must be preserved, conserved, and shared with people all over the world. Investigating archaeological heritage is valuable and plays an important role for the public good; our ancestors' cultures can be restored, and it helps with developing a clear understanding of the cultural and social aspects of a historical period as well as teaches about historical factors unreported in the literature. One of the most basic and important conditions necessary for recognizing the value and importance of archaeological heritage investigation, expertise, and quality improvement is to establish detailed criteria for investigation services and the qualification examination of archaeological heritage. Observation of detailed criteria and the qualification examination of archaeological heritage can partially demonstrate society's recognition of strengthening transparency, public property, and the objectivity of the investigation of archaeological heritage. However, the detailed criteria for investigation services and the qualification examination of archaeological heritage currently implemented as administrative rules are neither followed by all institutes in the public and private sectors nor the government. Thus, there are serious problems in terms of the effectiveness and stability of institutions. The detailed criteria for the qualification examination breach the principle of statutory reservation, the principle of statutory regulation, and regulations on the announcement and management of orders and rules. Non-compliance with compensation criteria for investigation services or with detailed criteria for the qualification examination of archaeological heritage will be one of the reasons for the failure of the investigation foundation for archaeological heritage in the future. That is, it will result in the expansion, reproduction, and repetition of a vicious cycle of conflict between developers, who are the decision-makers responsible for selecting an investigating organization for archaeological heritage and determining the cost, and investigating organizations. This includes the impractical shortening of investigation periods and reducing costs by developers, distrust of the values and the importance of investigations of archaeological heritage, a decrease in quality, accidents caused by a lack of safety, a lack of occupational ethics, and non-recruitment of new experts, etc. Therefore, it is necessary to change the structure from a vicious cycle to a virtuous cycle, and promote the enactment of regulations that will ensure effectiveness and stability in the process of attaining the goals of the institution and application of the institution, as well as the continuous advancement of work to fill the gaps with reality.

• Korean Journal of Health Education and Promotion
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• v.9 no.1
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• pp.1-13
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• 1992

The purpose of this thesis is to provide the framework of the health education curriculum on a school level which should be accomplishe in futrue and farthermore to establish the health education as a independent and regular course. The relation among the status in quo and the satisfaction degree of health education, the degree of the knowledge about health, the degree of the understanding of the health education and the degree of requirement for the health education curriculum has been analyzed in this paper. The research has been carried out through the questionnaire forms distributed to the girl students and the instructors at a few general senior high school and vocational senior high schools in Seoul, and the consequences are as follows : 1. As to the degree of understanding of the health education, it has been indicated that the health education should be performed one or two hours a week from the elementary school for all the boy and girl students by the experts trained in the departments concerned with health. 2. Concerning the degree of requirement for health education curriculum, the high school girl students have shown the need for first aid, sex education, environmental health, drinking, smoking, drug abuse, maternal and child health, industrial health, safety health, mental health, growth & development, epidemiology, the old health in the order named. On the other hand, the instructors have shown the need for drinking, smoking, drug abuse, sex education, maternal and child health, public health and industrial health also in the order named. The items having low degree of requirement are biostatistics, community health and health administration in case of the gril students and biostatistics, health administration and health economics in case of the instructors. 3. The status in quo and the satisfaction degree of the health education has proved higher in senior high school curriculums than in junior high school curriculums, and the most instructive course about health has turned out to be gymnastics in junior high school and the training course in senior high school respectively. 4. As to the degree of understanding of the health education in case of the girl students, the significance has been found between the health condition and the time for performing the health education, the monthly income and the objects for the health education, and the school records and the school hours per week. The significance has been shown only in regard to the school records in case of the degree of requriement for the health education curriculum. 5. The degree of requirement for the health education in case of the instructors has shown the significance between the teching career and the need for the health education. In addition, the degree of requirement for the health education curriculum has indicated significance with regard to sex and age. 6. The degress of the understanding of the health education according to the degree of knowledge about health and the degree of requirement for the health educatio curriculum have been all turned out to be statistically significant. 8. Among the factors which have an influence on the degree of the understanding of the health education, the recognition of the relation between the health course and the training course has significatly influenced the selection of the health education instructors. In additon, the understanding of the need for the health eduation has significantly influenced the objects for the instructors and the school hours, and the understanding of the need for establishing the health education course has significatly influenced the time for performing the health education.

• Journal of Science and Technology Studies
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• v.8 no.1
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• pp.97-129
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• 2008

We are living in the time of high probability of technological risk due to increased rate of technology development and diffusion of new technologies. Resolving uncertainties, the basic attribution of risk, by accumulating knowledge over the risk factors of certain technology is critical to management of technological risk. In many cases of technological risks, high uncertainty of knowledge is commonly mentioned reason for public controversies on risk management. However, the type of technological risk with low social agreement and low uncertainty of knowledge, the main reason for public controversy is absence of social agreement. Public debates on the risks of mobile phones electromagnetic fields(EMF) to human health comes under this category. The knowledge uncertainty on human health effect of mobile phones EMF has been lowered increasingly by accumulating enormous volume of knowledge though scientists have not reached a final conclusion whether it pose a risk to the physical and mental health of the general population or not. In contrast with civil organizations calling for precautionary approach based regulation, the mobile phone industry is cling to the position of no-regulation-needed by arguing no clear evidence to prove health risks of mobile phone EMF has found. In Korea, government set exposure standards based on a measurement called the 'specific absorption rate'(SAR) and require the mobile phone industry to open SAR information to the public by their own decision. From the view of pro-regulation side based on precautionary approach, technology risk managament of mobile phones EMF in Korea is highly limited and formalized one with limited measuring of SAR on head part only and problematic self-regulated opening of information about SAR to the public. As far as the government keeps having priority on protecting interest of mobile phone industry over precautionary regulation of mobile phones EMF, the disagreement between civil organizations and the government will not resolved. The risk of mobile phones EMF to human health have high probability of being underestimated in the rate and damage of risk than objectively estimated ones due to familiarity of mobile phone technology. And this can be the cause of destructive social dispute or devastating disaster. To prevent such disastrous results, technology risk management, which integrating the goals of safety with economic growth in public policy and designing and promoting risk communication, is required.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.1-2
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• 2011

Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.71-130
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• 2008

Using data from the Korean Labor & Income Panel Study (KLIPS), this study investigates private income transfers in Korea, where adult children have undertaken the most responsibility of supporting their elderly parents without well-established social safety net for the elderly. According to the KLIPS data, three out of five households provided some type of support for their aged parents and two out of five households of the elderly received financial support from their adult children on a regular base. However, the private income transfers in Korea are not enough to alleviate the impact of the fall in the earned income of those who retired and are approaching an age of needing financial assistance from external source. The monthly income of those at least the age of 75, even with the earning of their spouses, is below the staggering amount of 450,000 won, which indicates that the elderly in Korea are at high risk of poverty. In order to analyze microeconomic factors affecting the private income transfers to the elderly parents, the following three samples extracted from the KLIPS data are used: a sample of respondents of age 50 or older with detailed information on their financial status; a five-year household panel sample in which their unobserved family-specific and time-invariant characteristics can be controlled by the fixed-effects model; and a sample of the younger split-off household in which characteristics of both the elderly household and their adult children household can be controlled simultaneously. The results of estimating private income transfer models using these samples can be summarized as follows. First, the dominant motive lies on the children-to-parent altruistic relationship. Additionally, another is based on exchange motive, which is paid to the elderly parents who take care of their grandchildren. Second, the amount of private income transfers has negative correlation with the income of the elderly parents, while being positively correlated with the income of the adult children. However, its income elasticity is not that high. Third, the amount of private income transfers shows a pattern of reaching the highest level when the elderly parents are in the age of 75 years old, following a decreasing pattern thereafter. Fourth, public assistance, such as the National Basic Livelihood Security benefit, appears to crowd out private transfers. Private transfers have fared better than public transfers in alleviating elderly poverty, but the role of public transfers has been increasing rapidly since the welfare expansion after the financial crisis in the late 1990s, so that one of four elderly people depends on public transfers as their main income source in 2003. As of the same year, however, there existed and occupied 12% of the elderly households those who seemed eligible for the National Basic Livelihood benefit but did not receive any public assistance. To remove elderly poverty, government may need to improve welfare delivery system as well as to increase welfare budget for the poor. In the face of persistent elderly poverty and increasing demand for public support for the elderly, which will lead to increasing government debt, welfare policy needs targeting toward the neediest rather than expanding universal benefits that have less effect of income redistribution and heavier cost. Identifying every disadvantaged elderly in dire need for economic support and providing them with the basic livelihood security would be the most important and imminent responsibility that we all should assume to prepare for the growing aged population, and this also should accompany measures to utilize the elderly workforce with enough capability and strong will to work.