• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.135-143
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• 2017

The domestic unique research reactor, HANARO (Hi-flux Advanced Neutron Application ReactOr), has been constructed with the open-pool, the core is submerged in, for the multi-purpose neutron application. The reactor has a primary cooling system to remove the fission heat from the core and its connected fluidic systems. Since the works are required at the reactor pool top as a characteristic of the research reactor, the radiation shall be minimized with the operation of the hot water layer system to avoid unnecessary radiation exposure on the workers during work at the pool top. Moreover, the pool water management system is connected to the reactor pool to maintain the pool temperature below $50^{\circ}C$ to minimize the uprising radioactive gas or impurity from the colder pool bottom. For the efficient flow rate of the PWMS, the thermal capacity of heat exchanger is selected with 260 kW in the normal operation condition. In this paper, the modeling is formulated to figure out whether or not each pool temperature maintains below the temperature limit and the calculation results show that the designed PWMS heat exchanger has enough capacity with the design margin regardless of the reactor operation mode.

• Journal of Families and Better Life
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• v.23 no.4 s.76
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• pp.101-112
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• 2005

The purpose of this study was to provide the design guidelines for the activity spaces in the skilled nursing facilities for the elderly through the investigation of the spatial characteristics and using behavior The researcher interviewed the staff regarding programs in 15 facilities, investigated and observed the use of the spaces from 15th of December, 2004 to 19th of February, 2005. The programs in facilities were categorized into human knowledge, arts, music, exercise, recreation, cooking gardening, religious and social activities, and those were peformed once to 4 times a day. They were conducted in the elderly individual rooms, lounges, program rooms, dining room, or(and) auditorium. The results of the study were as follows: First, investigating the activity spaces, the lounges and elderly individual rooms were mostly on the same floor so that the elderly had no big trouble in access to the lounge. The program rooms of the facilities in suburban and rural area were on the same floor as the elderly individual rooms and they were likely to combine with another usage, compared to those On city were mostly separated from the residence floor. Most of dining rooms and auditorium were on the basement or on the 1st floor. Second, in the programs by the activity spaces, elderly individual room and the program room were used more for the human knowledge and art programs with small group. The lounges were for recreation and social activities with (both of) small or(and) big group and dining rooms were mainly used for cooking programs. In auditorium, recreation, religious and social activity were performed with big group. Third, the individual rooms for the elderly had more capacity if those did not have any beds, but often had a trouble in making a passage way. The lounges needed to remove decorations and displayed furniture obstructing the passages and to arrange both of the western and eastern type of tables for the efficient use of the spaces. It took a long time in preparation of the furniture and other equipment if the program room was with another usage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.1
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• pp.43-48
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• 2023

The biocompatibility and durability of implant fixtures are major concerns for dentists and patients. Mechanical complications of the implant include abutment screw loosening, screw fracture, loss of implant prostheses, and implant fracture. This case report aims to describe management of a case of fixture damage that occurred after screw fracture in a tissue level, internal connection implant and microscopic evaluation of the fractured fixture. A trephine bur was used to remove the fixture, and the socket was grafted using allogeneic bone material. The failed implant was examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), which revealed a fractured fixture with both normal and irregular bone patterns. The SEM and EDS results give an enlightenment of the failed fixture surface micromorphology with microfracture and contaminated chemical compositions. Noticeably, the significantly high level of gold (Au) on the implant surface and the trace amounts of Au and titanium (Ti) in the bone tissue were recorded, which might have resulted from instability and micro-movement of the implant-abutment connection over an extended period of time. Further study with larger number of patient and different types of implants is needed for further conclusion.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.13 no.2
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• pp.140-151
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• 2000

Acne is a common chronic disease which most frequently affects the face, appearing in both males and females near puberty, and in most cases becomes less active as adolescence ends. The intensity and duration of activity vary for each individual. The disease may be minor, with only a few comedones or papules, or it may occur as the highly inflammatory and diffusely scarring acne conglobation. Permanent scarring of the skin and psyche can result from such inaction. The disease, however, has implications far beyond the few marks that may appear on the face. The lesions cannot be hidden under clothing; each is prominently displayed and detracts significantly from one's personal appearance and self-esteem. Recently many of acne patients are visiting to Oriental Medicine Hospitals. They want to receive the treatment of acne related another disease and causes, or worry about side effects of antibiotics and hormone therapy. This study was performed at Pundang Cha Oriental Medicine Hospital Department of Dermatology from March 1, 1997 to February 29, 2000 in 31 patients with recurrent acne. We investigated the clinical findings, included distribution of age & sex, severity of acne, sites on face, related causes, duration of disease and causes of visiting Oriental Medicine Hospital and so on. The results were as follows : The peak age at onset was 20-29 years old in females with 16 cases reported. The 22 total cases patients had severe signs with most frequently sites being forehead & chin. They visited Oriental Medicine Hospital because they want to take the treatment of acne related with another body problems(12 cases) and worry about side effects of antibiotics. Twenty cases were diagnosed 肺熱血熱(20 cases). And given acupuncture treatment, herb-medication and sometimes we used external applications. Relatively, their satisfaction grade was high. Dermatologists are trying to treat new methods in order to remove scar and decrease sebaceous gland secretion,. And we, Oriental Medicine doctors, have to develop and offer to patients the most effective management and successful treatment of this disease.

• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.249-256
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• 2010

A phytoremediation study has been conducted to see if some known aquatic plants can remove the pesticides, endosulfan-${\alpha},\;{\beta}$ and fenitrothion which are frequently used in the crop protection and golf course management, and are likely to exist as residual pollutants in the aquatic ecosystems. Among the five aquatic plants tested in the microcosms, water lily Nymphaea tetragona Georgi showed the highest degradation efficacies (85~95%) for the three pesticides as opposed to the control(13~26%). The efficacies for the other plants were in the range of 46~80% in the order of Pistia stratiotes, Cyperus helferi, Eichhornia crassipes, and Iris pseudoacorus. Fenitrothion, an organo-phosphorus pesticide, was much more vulnerable to the phytoremediation than the organo-chlorine pesticides, endosulfan-${\alpha}$ and endosulfan-${\beta}$. The kinetic rate constants ($min^{-1}$) for removal of the three pesticides were more than 10 times higher than the control (non-planting) in case of Nymphaea tetragona Georgi. This aquatic plant showed kinetic rate constants about 2 times as much as the lower kinetic rate constants shown by Iris pseudoacorus. The reason for the highest degradation efficacy of water lily would be that the plant can live in the sediment and possess roots and broad leaves which could absorb or accumulate and degrade more pollutants in association with microbes. These results indicate that some of the selected aquatic plants planted near the agricultural lands and wetlands could contribute to remediation of pesticides present in these places, and could be applicable to protection of the aquatic ecosystems.

• Journal of Periodontal and Implant Science
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• v.44 no.5
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• pp.227-234
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• 2014

Purpose: Dentin hypersensitivity is a potential threat to oral health. Laser irradiation may provide reliable and reproducible treatment but remains controversial. The present study aimed to evaluate the effects of $CO_2$ or erbium-doped yttrium aluminium garnet (Er:YAG) laser therapy, and to assess mineral content. Methods: Eighteen human single-rooted teeth affected with advanced periodontitis were obtained. Buccal and lingual surfaces were planed to form 36 specimens. Ethylenediaminetetraacetic acid gel (24%) was applied to remove the smear layer and simulate hypersensitive teeth. The experimental groups were: group 1, control (no irradiation); group 2, $CO_2$ laser (repetitive pulsed mode, 2 W, $2.7J/cm^2$); and group 3, Er:YAG laser (slight contact mode, 40 mJ/pulse and 10 Hz). To evaluate dentinal tubule occlusion, six specimens per group (2-mm thickness) were prepared and observed using scanning electron microscopy (SEM) for calculation of the occlusion percentage. To evaluate the mineral content, six specimens per group (0.6-mm thickness) were used, and then the levels of Ca, K, Mg, Na, and P were measured by inductively coupled plasma-atomic emission spectrometry. In addition, the surface temperature of the specimens during laser irradiation was analyzed by a thermograph. Results: The SEM photomicrographs indicated melted areas around exposed dentinal tubules and a significantly greater percentage of tubular occlusion in the $CO_2$ and Er:YAG laser groups than the control, and in the Er:YAG group than the $CO_2$ laser group. In addition, no significant differences were noted among the experimental groups for the mineral elements analyzed. The $CO_2$ laser group showed an evident thermal effect compared to the Er:YAG group. Conclusions: $CO_2$ and Er:YAG laser are effective in treating dentin hypersensitivity and reducing its symptoms. However, the Er:YAG laser has a more significant effect; thus, it may constitute a useful conditioning item. Furthermore, neither $CO_2$ nor Er:YAG lasers affected the compositional structure of the mineral content.

• Korean Journal of Veterinary Service
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• v.45 no.4
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• pp.263-268
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• 2022

The current study examined the impact of fermented barley sprout extract prepared using lactic acid bacteria (Lactobacillus sp.) in decreasing odor and increasing livestock productivity and measured the difference in the polyphenol and flavonoid contents of the extract after fermentation. Furthermore, the effectiveness of fermented barley sprout extract was evaluated through order level and production index of livestock by supplying it to a broiler house. The results showed that with fermented barley sprout extract, the polyphenol and flavonoid contents were increased significantly by 174% and 562%, respectively. When the extract was applied as an additive to drinking water in the test farm, the productivity improved by about 10%, the mortality rate was reduced by about 66%, and there was a significant decrease in odor by about 80%. Compared with the control group, the production index increased by about 21%, the feed requirement decreased by about 8%, the odor showed a decrease in the NH₃ level, and no other gas was detected. It was observed that lactic acid bacteria settle in the intestine, suppress the proliferation of bacteria that cause diarrhea and enteritis, and help digestion. The lactic acid bacteria effectively remove bad odor gases such as NH₃, Amines, H₂S and CH₄S. Such odor reduction improves productivity. Our findings provide valuable information for quality water supply, production optimization and livestock management.

• 한국디지털정책학회:학술대회논문집
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• 2005.06a
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• pp.107-143
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• 2005

Mobile service that geography, position by development of space Information Technology and technology of communications, space are various to us now becoming limelight as point contents and infra information that customers do demand based on radio superhigh speed authentication net on highly information society by offer infringement problem about individual's privacy or information by political and scientific interest be injured. Purpose of this study grasps use factor of LBS application Mobile service, and it is that analyze actual proof through questionnaire to grasp whether some relation is with value and action determination that is felt of LBS application Mobile service. Distributed all question of 190 copies but disk floret inclination did valid data 171 that clear question and omission remove a lot of questions by type of study among questionnaire of collected 182 wealths. Analyzed factor analysis and authoritativeness to search validity and confidence of questionnaire and used single regression analysis and multiple regression analysis for hypothetical verification. According to verification result, Mobile service that apply position base service usefulness and system quality, adaptedness of Mobile service that apply position base service by leading person affecting in use, acted for connection healthy and felt value is important factor immediately. Usability and social effect, felt expense, privacy did not appear by leading person that keep in mind in this study. Is been related with step that Mobile service that apply position base service is placed. That is, as present childhood, a person who have experience that use service to look for friend is few and usability fairly in last in wide application boundary and this very important person was removed finally in model. This study has sense in terms of study systematically about LBS application service use leading person that is getting into the spotlight worldwide among Mobile service that is injured newly.

• Journal of environmental and Sanitary engineering
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• v.6 no.1
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• pp.7-25
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• 1991

Until now, pure drinking water grnerally menas the water without taste, odor, general bacteria, coliform, and other exotic substance. Such a definition has been changing recently due to the finding of numerous other inorganic and organic substances unknown to us. 10 years ago, major causes of death were infectious agents and parasites contained in water, but recently, it has become apparent that some substances contained in drinking water cause cancer and heart diseases. We must drink about 2L of water everyday in order to maintain healthy condition. Waters used for drinking include tap water, well water, spring water, filtered water, etc., but the quality of drinking water has more polluted due to the industrial development and population increase. For example, industrial waste waters from industrial plants pollute the water supply sources ; toxic substances contained in the waste waters pollute the ground water sources by penetrating the geological strata, and municipal, livestock, public building waste waters also pollute the water supply sources. Sometimes, the polluted surface waters were announced to be polluted by various kinds of orgainc substance, and it is reported that the pollution of ground water by orga nic substances has few in number but high in its concectration comparing with those of surface water. As the water quality pollution level increases, so the amount of disinfectant also increase. For example, chlorine solution, one of widely used disinfectants, creates trihalomethane(THM), a carcinogen, and halogen compounds. According to Oliver, through chlorine disinfection process, humine substance and chlorine create bolatile organic halide and nonvolatile organic halide by chemical reaction. There are tens or hundreds filtering devices, but filtering principles and maintenance metjhods are different, so their efficiency tests are needed. According to Smith, the effeciency tests aginst over 30 Ameican filtering devices show that 10 devices can remove 85% of volatile organics and further studies on filtered waters are underway. In consideration of important impacts of polluted drinking water on national health, authors studied the state of water quality pollution against tap water used as drinking water, filtration device passed water, ground water, and conserved drinking water ; tested the efficiency of filtration devices for tap water ; tried to sep up the detection method by using ion chromatography based on negative ion and positive ion by using single column, and attemped the simple filtration method for general households.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.5
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• pp.464-467
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• 2001

Aplastic anemia is a hematopoietic disorder characterized by marked reduction or absence of erythoid, granulocytic, and megakariocytic cells in the bone marrow with resultant pancytopenia. To control of infection & bleeding secondary to leukopenia and thrombocytopenia, the inflammatory lesions in oral & maxillofacial area should be removed. Material & Method: The extractions were performed on 21 patients with severe aplastic anemia. The initial, pre-operative and postoperative CBCs were checked up. Amount and kind of transfused platelet in each patient and increment of platelet level were recorded. The complications were documented. Result : A mean of 2.9 teeth were extracted from each patient(ranging between 1 and 13). Furthermore, surgical extractions including ostectomy and odontectomy of the third molar were performed on 11 patients. The preoperative WBC levels presented between $600/{\mu}L$ and $5000/{\mu}L$(mean $2376/{\mu}L$). The WBC values decreased by an average of $145/{\mu}L$ per patient after extractions had been performed. The teeth of 16 patients were extracted under 10.0g/dL, and the mean change in postoperative hemoglobin levels in comparison with preoperative hemoglobin levels was -0.06 per patient. The initial platelet levels were between 1000/(L and $81,000/{\mu}L$(mean $20,174/{\mu}L$). In five patients, extractions were performed with platelet levels less than $50,000/{\mu}L$. Conclusion : The results suggest that more active and preventive treatments in the oral and maxillofacial area are possible and are necessary to remove the infectious foci on the patients with severe aplastic anemia. We report the results of our experiences and literature reviews in treatment of the patients with severe aplastic anemia in our department.