• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.63-74
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• 2006

During the construction of circular underground pipe, the non-proper compaction along the pipe and the decrease of compaction efficiency have been the main problems to induce the failure of underground pipe or facility. The use of CLSM (controlled low strength materials) should be one of the possible applications to overcome those problems. In this research, the full-scaled field test and the numeric analysis using PENTAGON-3D FEM program were carried out for three different cases on the change of backfill materials, including the common sand, the soil from construction site, and the CLSM. From the full-scaled test in field, the use of in-situ CLSM as backfill materials reduced the vertical and lateral deformation of the pipe, as well as the deformation of the ground surface. The main reason for reducing the deformation would be the characteristics of the CLSM, especially self-leveling and self-hardening properties. The measured earth pressure at the surround of the corrugated pipe using the CLSM backfills was the smaller than the other cases, and the absolute value was almost zero. Judging from the full-scaled field test and FEM analysis, the use of CLSM as backfill materials should be one of the best choices reducing the failure of the underground pipes.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.95-120
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• 1996

College level educational training system for the allied health manpower in the country is one of the oldest junior college education programs, and has been developed at very steady phase. Since the school years of the programs limited for 2 to 3 years by the education related law, qualification of the manpower is insufficient to meet the rapidly changing needs in the field of allied health and medicine. The system is comparable with that of developed countries where 4-year baccalaureate degree programs are basically required to be an allied health personnel. Thus, education and training background of allied health program graduates of the country confronts the barriers in competition and cooperation with the graduates of foreign countries at equal basis. Beside, junior college graduates can hardly find the way through advanced courses at 4-year colleges in their specialties except a few programs such as environmental sicience or courses in hygiene. It has long been sought to develop the education and training programs for junior college graduates. Some of them are already materilized and some show remarkable progress while some need to tackle. Wide opening of the opportunity to enroll extensive education program for the junior college graduates of allied health science majors in 4-year colleges with eventual grant of bachelor's degree for those who successfully completed the programs should soon be substantiated. The study was focused to emphasize the necessity of the extensive education and training for the junior college graduate allied health manpower, and to show possibility of the education program development in connection with the 4-year degree granting education programs. The outcome of the study can be summarized as followings. 1. A total number of graduates from eight allied health sciences related programs of junior colleges by the year of 1995 are 109,320. 2. According to the survey report analysed through questionnaires, 99.7% of respondents including administrative deans and professors of junior colleges agreed with the establishment of extensive education and training programs in junior colleges. 53.9% of administrative deans, 52.9% of professors and 47.6% of the graduates expected that it is possible to learn more about their majors, and to earn bachelor's degree through the extensive education programs. Other opinions include that the programs can provide supplementary opportunities to fortify in the area of basic life science, and development of research and technology. 3. It was also found through the survey that 91.2% of the deans, 87.8% of the professors and 68.2% of the graduates responded that the most appropriate organizations to open the extensive education and training programs for allied health manpower are junior colleges where allied health personnel are taught and trained. The majority of the respondents agreed that the acceptable number of credits offered for the previous 2-year junior college graduates are $50\sim60$, and those for the current 3-year graduates are $20\sim30$ units. 4. It was strongly suggested through the survey that baccalaureate degree should be granted for those who successfully completed the extensive courses. The suggestion was claimed by 94.1% of the deans, 89.4% of the professors and 83.4% of the graduates. 5. The model curricula for the extensive education and training programs for the allied health manpower are designed for the purpose of broad capability in practice, enrichment of knowledge and promotion of proficiency for the self access in the major areas. 6. To meet the universal standards of allied health education and training program, it is recommended that opening of the curricula for the extensive, and as well as intensive, courses within junior colleges(continuation education institute) should be materialized. The special baccalaureate degree programs within junior colleges are also recommended to accommodate the junior college graduates and to grant the degree fellowing successful completion of the courses. As a part of the education revolution in progress, the school years at junior college level should be flexible depending upon the nature of course and trend of the universe. For instance, the school years for the allied health manpower should be extended to two to four years from current two to three years.

• Journal of radiological science and technology
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• v.40 no.3
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• pp.461-468
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• 2017

This study measured and compared the protective clothing using Pb used for shielding in a diagnostic X-ray energy range, and the shielding rates of X-ray fusion shielding materials using Si and $TiO_2$. For the experiment, a pad type shielding with a thickness of 1 mm was prepared by mixing $Si-TiO_2$, and the X-ray shielding rate was compared with 0.5 mmPb plate of The shielding rate of shielding of 0.5 mmPb plate 95.92%, 85.26 % based on the case of no shielding under each 60 kVp, 100 kVp tube voltage condition. When the shielding of $Si-TiO_2$ pad was applied, the shielding rate equal to or greater than 0.5 mmPb plate was obtained at a thickness of 11 mm or more, and the shielding rate of 100% or more was confirmed at a thickness of 13 mm in 60 kVp condition. When the shielding of $Si-TiO_2$ pad was applied, the shielding rate equal to or greater than 0.5 mmPb plate was obtained at a thickness of 17 mm or more, and a shielding rate of 0.5 mmPb plate was observed at a thickness of 23 mm in 100 kVp condition. Through the results of this study, We could confirm the possibility of manufacturing radiation protective materials that does not contain lead hazard using various metalic compound and liquid Si. This study shows that possibility of liquid Si and other metalic compound can harmonize easily. Beside, It is flexible and strong to physical stress than Pb obtained radiation protective closthes. But additional studies are needed to increase the shielding rate and reduce the weight.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.145-158
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• 1994

This study was performed to investigate the knowledge and attitude of workers in small scale industries on health management, and to provide the basic data for more effective service by the group occupational health service system. The knowledge and attitude of 247 workers and 46 health personnel in the industries scattered around Incheon were investigated from December 1992 to February 1993. The results were summerized as follows ; 1. There were significant differences between the workers and the health personnel by age, sex, marriage status, job-position and education level. 2. The recognition level of the workers to contract work related disease was significantly higher than that of health personnel, and recognition level of the workers on environmental hazards and on the utility of measuring hazards were lower than that of health personnel. 3. The recognition level on the content of the group occupational health service system was significantly different between workers and health personnel, 72.6% of the responses from the workers answered that they did not know what the group occupational healthe service system was, but 82.2% of the responses from the health personnel answered that they knew well what it was. And 79.0% of all respondents thought it was necessary for worker's health. 4. Seventy three percent of the respondents from the workers indicated that they had never taken health education. However, 93.0% of all respondents answered positively for the need of health education to promote their health. 5. Current health service system was judged to be insufficient for the demand of workers for better health. Most of the respondents prefered a formal but flexible health service system and they wanted the periodic health examination to be followed up. It was revealed that despite of poor knowledge, the demand of workers for health service was higher than the current supply. Therefore, this study suggests that educating both health personnel and workers to obtain correct knowledge on the hazards to work enviroment and health management is needed for effective occupational health service.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.11-24
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• 1994

The studies reported here were undertaken to investigate the effects of mercury chloride on immune system of Balb/c mouse employing a flexible tier of in vitro and in vivo assays. Mercury chloride inhibited the proliferative responses of spleen cells to lipopolysaccharide, pokeweed mitogen, and phytohemagglutinin as a dose-dependent manner. This inhibitory effect was observed not only when $HgCl_2$ was added 2nd or 3rd day of 3 days culture period but also when spleen cells was pretreated with $HgCl_2$ for 2 hours. Mercury chloride, however, potentiated the production of IgM and IgG from spleen cells. During the $HgCl_2$ administration by drinking for 3 weeks, the weight gain of mice was significantly blunted than that o control group mice, while no overt signs related to mercury toxicity were noted in any mice of experimental group. There was no change in thymus and spleen weights, and in histological findings of kidney, bone marrow of femur, thymus, spleen, and popliteal lymph node after 3 weeks of mercury exposure. However, $HgCl_2$ induced a significant increase of total serum IgM, IgG including $IgG_1,\;IgG_{2a}\;and\;IgG_{2b}$, and IgE in Balb/c mice. Treatment in vivo with anti-IL-4 monoclonal antibody significantly abrogated the $HgCl_2$-induced increase in total serum IgG1 and IgE. Whereas $HgCl_2$ potentiated total serum IgM and IgG, there was no difference in total serum hemagglutinin to SRBC (Sheep Red Blood Cell) between experimental and control group mice when these mice were immunized with SRBC. All these findings observed in Balb/c mice suggest that mercury perturbates well-orchestrated regulation of immune responses before developing histopathological changes in lymphoid tissues.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.35-42
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• 2004

Background: For the treatment of isolated left main coronary artery disease, twelve arterial revascularizations with Y-composite grafts using left internal thoracic artery and radial artery or right gastroepiploic artery were peformed. This study was performed to investigate whether V-composite graft can satisfy the blood flow required to make myocardium act properly or not. Borderline stenotic lesions on the left main coronary artery, which are very prone to remodel the bypassed vessels due to competitive flows, were also considered. Material and Method: Among 247 patients who underwent coronary artery bypass grafting from March 2000 to April 2003, 12 patients (4.7%) who had received total arterial revascularizations for the isolated left main coronary artery disease were studied retrospectively. Result: left anterior descending arteries were bypassed with left internal thoracic artery by off-pump technique in all patients, however, 2 cases of left obtuse marginal branches were bypassed under on-pump beating heart. Except for one patient, who did not have an obtuse marginal branch more than 1 mm in diameter, 11 patients had gone through complete arterial revascularizations by use of the Y shape arterial graft. Among five patients who had less than 75% stenosis, one patient showed string sign on left internal thoracic artery grafted to left anterior descending artery. However, two grafts to obtuse marginal blanches were completely obstructed and one showed slender sign. There were no graft-dominant flow in patients with stenotic lesion less than 75%. On the contrary to the result of patients with stenotic lesions less than 75%, all the patients with stenotic lesions more than 90% showed graft-dominant blood flow. Conclusion: In conclusion, it is assumed that, when stenotic lesions are over 90%, coronary artery bypass grafting with an Y shape arterial graft could possibly give enough help to the obstructed coronary arteries in blood supplying to myocardium, which needs massive quantity of blood to act well. However, when patients have borderline stenoses, through scrupulous examinations, more prudent and flexible decisions are required in choosing the treatment methods, such as, direct anastomosis of vein or artery to aorta, or adding supplementary treatment methods like percutaneous coronary intervention, rather than choosing a fixed treatment methods.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.17-20
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• 1970

Occasionally, We make mistake of discrimination of sex since a pair of small spots around tile abdomen of 9th abdominal of males and posterior spots of females of the silkworms larvae are found at almost same position. As already have reported, more larvae which have the small spots were found in Chinese race than the Japanese. This research has been conducted in order to grasp the rate of appearance of the small spotted larvae hereditarily when hybridize with different race (F$_1$) 1. According to the first report, average 17,8％ of the small spotted larvae are found in the Japanese race and 57.0％ in the Chinese, but my re-invested data which was carried out recently shows that average 13.6％ in the former case and 37.8％ in the latter. Those new data are supposed to be come to a conclusion that the figures are flexible but in any case high frequency of appearance of the larvae were found in the Chinese race than the Japanese (Reference Table 1 ) 2. Miscalculated ratio of the larvae from males to females are 1.2-2.6％, and from females to males are found 0.5％-0.9％ in the Japanese race, In case of the Chinese race, 7.1-9.4％ in tile former and 2.9-3.4％ in the latter. Those data also shows that more of the larvae found in Chinese race. 3. The larvae of small spotted and non-spotted are also seperated when hlybridize with different mating types and races. 4. More small spotted larvae are seen when hybridize with less appeared of the small spots of females and males which have the small spots than more appeared of the small spots of females with none spotted of the males (Reference Table 2. C.G.)B.F.). 5. More larvae of the small spots and found in case of hybridize in a group of having small spots than none of the spots (H>E). 6. With the exception of the case (A.B), in the same type of cross breeding (C.D, E.F, G,H), more larvae of the smal1 spots are also found in case of hybridize with males of having the spots than none of the spots.

• Analytical Science and Technology
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• v.6 no.1
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• pp.29-37
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• 1993

Some new podands containing phenyl(B), benzyl(Bz), pyridine(Py), quinoline(Q) and naphthalene(Np) as end-groups, and oxygen(O) and sulfur(S) in ether chains as donor atoms have been synthesized. The univalent cation binding characteristics of these podands have been studied by NMR titration and solvent extraction. By NMR titration we have found that the most of podands form 1:1 complexes with $Ag^+$ ion. Especially, the substituted sulfur atoms in ether chains show the effects to enhance the stabilities. We also carried out the extractions of univalent cation picrates including alkaline metal, $Ag^+$, $Tl^+$ and $NH_4{^-}$ ions from aqueous to chloroform layer by using these podands. We found that the extractabilities of $Ag^+$ ion with the quinoline-containing podands such as, $Q_2O_4$, $Q_2O_5$ and $BQO_5$ were 86.8, 86.6 and 48.0% respectively, but the naphthalene-containing podands such as, $Np_2O_4$ and $Np_2O_5$ extracted quite small amount. Otherwise, in cases of $Bz_2O_3S_2$(89.4%), $B_2O_2S_2$(96.8%), $B_2O_3S_2$(58.9%), $Py_2O_2S_2$(58.8%), $Py_2O_3S_2$(42.1%), and $B_2O_4S$(15.0%), interestingly, $Bz_2O_3S_2$ which have sulfur atoms and benzyl groups showed the highest extraction selectivity for $Ag^+$ ion. This result seems due to not only the strong interaction of $Ag^+$ ion with sulfur donors according to the HSAB theory, but also the effective ${\pi}-{\pi}$ stacking interaction between two aromatic end-groups which is enhanced by the flexible methylene spacing group in benzyl groups instead of phenyl groups. The extraction coefficients gave the similar tendency as the extractabilities and the stabilities. From these results, it could be concluded that the predominant factor affected to extraction coefficients is the stabilities, which are strongly influenced by the structures of podands.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.101-111
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• 2017

Mineral carbonation is a technology in which carbonates are synthesized from minerals including serpentine and olivine, and industrial wastes such as slag and cement, of which all contain calcium or magnesium when reacted with carbon dioxide. This study aims to develop the mineral carbonation technology for commercialization, which can reduce environmental burden and process cost through the reduction of carbon dioxide using steel slag and the slag reuse after calcium extraction. Calcium extraction was conducted using NH4Cl solution for air-cooled slag and convert slag, and ${\geq}98%$ purity calcium carbonate was synthesized by reaction with calcium-extracted solution and carbon dioxide. And we conducted experimentally to minimize the quantity of by-product, the slag residue after calcium extraction, which has occupied large amount of weight ratio (about 80-90%) at the point of mineral carbonation process using slag. The slag residue was used to replace silica sand in the manufacture of cement panel, and physical properties including compressive strength and flexible strength of panel using the slag residue and normal cement panel, respectively, were analyzed. The calcium concentration in extraction solution was analyzed by inductively coupled plasma optical emission spectrometer (ICP-OES). Field-emission scanning electron microscope (FE-SEM) was also used to identify the surface morphology of calcium carbonate, and XRD was used to analyze the crystallinity and the quantitative analysis of calcium carbonate. In addition, the cement panel evaluation was carried out according to KS L ISO 679, and the compressive strength and flexural strength of the panels were measured.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.2
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• pp.106-111
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• 2012

Purpose: The purpose of this study was to compare the effect of 3 chairside polishing methods and laboratory polishing methods on surface roughness and $C.$ $albicans$ adhesion of polyamide denture base. Materials and methods: Using contact profilometer, the surface of polyamide specimens ($25{\times}15{\times}2mm$) was studied after conventional polishing without finishing and after chiarside polishing with 2 chiarside polishing kits and chairside-pumice polishing following finishing with tungsten carbide bur. To evaluate the adhesion of $C.$ $albicans$, $C.$ $albicans$ suspension was overlayed on the test specimen. And the specimens were incubated for 2 hours. Imprint culture method was achieved and counted the colony on the agar plate. Polished polyamide were evaluated using a scanning electron microscope. The statistics were conducted using one-way ANOVA and in case of difference, Scheffe test and Tamhane's T2 test were used. Results: Surface roughness (Ra) of surfaces polished with 2 chairside polishing kits had higher than conventional polishing and pumice polishing. The highest roughness value was $0.32{\pm}0.10{\mu}m$, and the lowest was $0.02{\pm}0.00{\mu}m$. The adhesion of $C.$ $albicans$ on the specimens polished with chairside polishing group and pumice polishing group were increased than conventional polishing group ($P$<.01). Conclusion: Conventional laboratory polishing was found to produce the smoothest surface and the lowest adhesion of $C.$ $albicans$. Two groups polished with Chairside polishing kits were similar with respect to surface roughness. Surface of the specimen polished with pumice is significantly smoother than 2 chairside polishing groups, but the result of $C.$ $albicans$ adhesion is that group polished with pumice was similar with 2 chairside polishing groups ($P$>.01).