• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.979-995
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• 1997

The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.186-193
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• 2005

Purpose: To improve the management of a medical linear accelerator, the records of operational failures of a Varian CL2l00C over a ten year period were retrospectively analyzed. Materials and Methods: The failures were classified according to the involved functional subunits, with each class rated Into one of three levels depending on the operational conditions. The relationships between the failure rate and working ratio and between the failure rate and outside temperature were investigated. In addition, the average life time of the main part and the operating efficiency over the last 4 years were analyzed. Results: Among the recorded failures (total 587 failures), the most frequent failure was observed in the parts related with the collimation system, including the monitor chamber, which accounted for $20\%$ of all failures. With regard to the operational conditions, 2nd level of failures, which temporally interrupted treatments, were the most frequent. Third level of failures, which interrupted treatment for more than several hours, were mostly caused by the accelerating subunit. The number of failures was increased with number of treatments and operating time. The average life-times of the Klystron and Thyratron became shorter as the working ratio increased, and were 42 and $83\%$ of the expected values, respectively. The operating efficiency was maintained at $95\%$ or higher, but this value slightly decreased. There was no significant correlation between the number of failures and the outside temperature. Conclusion: The maintenance of detailed equipment problems and failures records over a long period of time can provide good knowledge of equipment function as well as the capability of predicting future failure. Wore rigorous equipment maintenance Is required for old medical linear accelerators for the advanced avoidance of serious failure and to improve the qualify of patient treatment.

• The Journal of Dong Guk Oriental Medicine
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• v.10
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• pp.119-145
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• 2008

Through a simple study of the medical classics in the '$\bar{A}yurveda$', we have summarized them as follows. 1) Traditional Indian medicine started in the Ganges river area at about 1500 B. C. E. and traces of medical science can be found in the "Rigveda" and "Atharvaveda". 2) The "Charaka(閣羅迦集)" and "$Su\acute{s}hruta$(妙聞集)", ancient texts from India, are not the work of one person, but the result of the work and errors of different doctors and philosophers. Due to the lack of historical records, the time of Charaka(閣羅迦) or $Su\acute{s}hruta$(妙聞)s' lives are not exactly known. So the completion of the "Charaka" is estimated at 1st$\sim$2nd century C. E. in northwestern India, and the "$Su\acute{s}hruta$" is estimated to have been completed in 3rd$\sim$4th century C. E. in central India. Also, the "Charaka" contains details on internal medicine, while the "$Su\acute{s}hruta$" contains more details on surgery by comparison. 3) '$V\bar{a}gbhata$', one of the revered Vriddha Trayi(triad of the ancients, 三醫聖) of the '$\bar{A}yurveda$', lived and worked in about the 7th century and wrote the "$Ast\bar{a}nga$ $Ast\bar{a}nga$ hrdaya $samhit\bar{a}$ $samhit\bar{a}$(八支集) and "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$(八心集)", where he tried to compromise and unify the "Charaka" and "$Su\acute{s}hruta$". The "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$" was translated into Tibetan and Arabic at about the 8th$\sim$9th century, and if we generalize the medicinal plants recorded in each the "Charaka", "$Su\acute{s}hruta$" and the "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$", there are 240, 370, 240 types each. 4) The 'Madhava' focused on one of the subjects of Indian medicine, '$Nid\bar{a}na$' ie meaning "the cause of diseases(病因論)", and in one of the copies found by Bower in 4th century C. E. we can see that it uses prescriptions from the "BuHaLaJi(布唅拉集)", "Charaka", "$Su\acute{s}hruta$". 5) According to the "Charaka", there were 8 branches of ancient medicine in India : treatment of the body(kayacikitsa), special surgery(salakya), removal of alien substances(salyapahartka), treatment of poison or mis-combined medicines(visagaravairodhikaprasamana), the study of ghosts(bhutavidya), pediatrics(kaumarabhrtya), perennial youth and long life(rasayana), and the strengthening of the essence of the body(vajikarana). 6) The '$\bar{A}yurveda$', which originated from ancient experience, was recorded in Sanskrit, which was a theorization of knowledge, and also was written in verses to make memorizing easy, and made medicine the exclusive possession of the Brahmin. The first annotations were 1060 for the "Charaka", 1200 for the "$Su\acute{s}hruta$", 1150 for the "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$", and 1100 for the "$Nid\bar{a}na$". The use of various mineral medicines in the "Charaka" or the use of mercury as internal medicine in the "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$", and the palpation of the pulse for diagnosing in the '$\bar{A}yurveda$' and 'XiZhang(西藏)' medicine are similar to TCM's pulse diagnostics. The coexistence with Arabian 'Unani' medicine, compromise with western medicine and the reactionism trend restored the '$\bar{A}yurveda$' today. 7) The "Charaka" is a book inclined to internal medicine that investigates the origin of human disease which used the dualism of the 'Samkhya', the natural philosophy of the 'Vaisesika' and the logic of the 'Nyaya' in medical theories, and its structure has 16 syllables per line, 2 lines per poem and is recorded in poetry and prose. Also, the "Charaka" can be summarized into the introduction, cause, judgement, body, sensory organs, treatment, pharmaceuticals, and end, and can be seen as a work that strongly reflects the moral code of Brahmin and Aryans. 8) In extracting bloody pus, the "Charaka" introduces a 'sharp tool' bloodletting treatment, while the "$Su\acute{s}hruta$" introduces many surgical methods such as the use of gourd dippers, horns, sucking the blood with leeches. Also the "$Su\acute{s}hruta$" has 19 chapters specializing in ophthalmology, and shows 76 types of eye diseases and their treatments. 9) Since anatomy did not develop in Indian medicine, the inner structure of the human body was not well known. The only exception is 'GuXiangXue(骨相學)' which developed from 'Atharvaveda' times and the "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$". In the "$Ast\bar{a}nga$ Sangraha $samhit\bar{a}$"'s 'ShenTiLun(身體論)' there is a thorough listing of the development of a child from pregnancy to birth. The '$\bar{A}yurveda$' is not just an ancient traditional medical system but is being called alternative medicine in the west because of its ability to supplement western medicine and, as its effects are being proved scientifically it is gaining attention worldwide. We would like to say that what we have researched is just a small fragment and a limited view, and would like to correct and supplement any insufficient parts through more research of new records.

• The Journal of Korean Society for Radiation Therapy
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• v.28 no.2
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• pp.171-178
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• 2016

Purpose : In order to minimize the dose of femoral head as an appropriate treatment plan for rectal cancer radiation therapy, we compare and evaluate the usefulness of 3-field 3D conformal radiation therapy(below 3fCRT), which is a universal treatment method, and 5-field 3D conformal radiation therapy(below 5fCRT), and Volumetric Modulated Arc Therapy (VMAT). Materials and Methods : The 10 cases of rectal cancer that treated with 21EX were enrolled. Those cases were planned by Eclipse(Ver. 10.0.42, Varian, USA), PRO3(Progressive Resolution Optimizer 10.0.28) and AAA(Anisotropic Analytic Algorithm Ver. 10.0.28). 3fCRT and 5fCRT plan has $0^{\circ}$, $270^{\circ}$, $90^{\circ}$ and $0^{\circ}$, $95^{\circ}$, $45^{\circ}$, $315^{\circ}$, $265^{\circ}$ gantry angle, respectively. VMAT plan parameters consisted of 15MV coplanar $360^{\circ}$ 1 arac. Treatment prescription was employed delivering 54Gy to recum in 30 fractions. To minimize the dose difference that shows up randomly on optimizing, VMAT plans were optimized and calculated twice, and normalized to the target V100%=95%. The indexes of evaluation are D of Both femoral head and aceta fossa, total MU, H.I.(Homogeneity index) and C.I.(Conformity index) of the PTV. All VMAT plans were verified by gamma test with portal dosimetry using EPID. Results : D of Rt. femoral head was 53.08 Gy, 50.27 Gy, and 30.92 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. D of Rt. aceta fossa was 54.86 Gy, 52.40 Gy, 30.37 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. The maximum dose of both femoral head and aceta fossa was higher in the order of 3fCRT, 5fCRT, and VMAT treatment plan. C.I. showed the lowest VMAT treatment plan with an average of 1.64, 1.48, and 0.99 in the order of 3fCRT, 5fCRT, and VMAT treatment plan. There was no significant difference on H.I. of the PTV among three plans. Total MU showed that the VMAT treatment plan used 124.4MU and 299MU more than the 3fCRT and 5fCRT treatment plan, respectively. IMRT verification gamma test results for the VMAT plan passed over 90.0% at 2mm/2%. Conclusion : In rectal cancer treatment, the VMAT plan was shown to be advantageous in most of the evaluation indexes compared to the 3D plan, and the dose of the femoral head was greatly reduced. However, because of practical limitations there may be a case where it is difficult to select a VMAT treatment plan. 5fCRT has the advantage of reducing the dose of the femoral head as compared to the existing 3fCRT, without regard to additional problems. Therefore, not only would it extend survival time but the quality of life in general, if hospitals improved radiation therapy efficiency by selecting the treatment plan in accordance with the hospital's situation.

• The Korean Journal of Air & Space Law and Policy
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• v.27 no.2
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• pp.29-65
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• 2012

Der neue strukturelle Ansatz der Kommbination eines Rahmen$\ddot{u}$bereinkommens und eines ausr$\ddot{u}$stungsspezifischen Sonderprotokolls bedingt einen neuen organisatorischen Anstz f$\ddot{u}$r die Zusammenarbeit zwischen internationalen Organisationen bei der Schaffung von internationalem Einheitsprivatrecht. So haben hier zwei internationale Organisationen gemeinsam die Verantwortung f$\ddot{u}$r einmultilaterales $\ddot{U}$bereinkommen $\ddot{u}$bernommen: auf der einen Seite UNIDROIT als die internationale Organisation, die generell f$\ddot{u}$r die Vereinheitlichung des Privatrechts kompetent ist; auf der anderen Seite ICAO als die f$\ddot{u}$r die private Luftfahrt zust$\ddot{a}$ndige internationale Organisation. Dieses neue, f$\ddot{u}$r die Luftfahrzeugausr$\ddot{u}$stung praktizierte organisatorische Modell eines joint venture zweier internationaler Organisation bei der Einheitsrechtsetzung, namlich die Betreuung eines allgemeinen privatrechtsvereinheitlichenden Rahmens$\ddot{u}$bereinkommens durch UNIDROIT und die Wahrnehmung der sektorspezifischen Belange in einem ausr$\ddot{u}$stungsspesifischen Sonderprotokoll durch die jeweils zust$\ddot{a}$ndige internationale Spezialorganisation, hat bereits f$\ddot{u}$r die Sektoren der Eisenbahn- und Weltraumausrustung Schule gemacht. Das in Kapstadt beschlossene v$\ddot{o}$lkervertragliche Regelungswerk hat erstmals ein einheitsrechtliches - grunds$\ddot{a}$atzlich weltweite Geltung anstrebendes - Sicherungsrecht geschafen. Dies kann f$\ddot{u}$r die Sachenrechtsintergration einen $\ddot{a}$hnlichen Durchbruch bedeuten, wis das Wiener UN-kaufrechts$\ddot{u}$bereinkommen von 1980 f$\ddot{u}$r das Schuldvertragsrecht. Voraussetzung daf$\ddot{u}$r ist allerdings die juristische Qualit$\ddot{a}$t und Praxisgerechtigkeit des Regelungswerkes und - insbesondere - das Funktionieren des Registersystems. Von wesentlicher Bedeutung f$\ddot{u}$r den Erfolg des $\ddot{U}$bereinkkommens wird auchsein, ob es Rechtssicherheit zu gew$\ddot{a}$hrleisten vermag.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.1-18
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• 2016

This study was carried out to investigate the flora of the western front (Paju-Yencheon Area) of the Civilian Control Zone. Vascular plants collected in these areas were a total of 558 taxa composing of 501 species, 3 subspecies, 48 varieties and 1 forma of 330 genera under 109 families This shows that 11% of the 4,880 vascular plant species that are known to exist in Korea is distributed in the western part of the DMZ. 1 taxa of endangered species designated by the Ministry of Environment was found: the Polygonatum stenophyllum Maxim in the edge of the military operation road from Taepung observatory to Imjin river. For the floristically specific ones of the Korean floristic zones, 3 taxa of the $5^{th}$ grade, 3 taxa of the $4^{th}$ grade, 13 taxa of the $3^{rd}$ grade, 13 taxa of the $2^{nd}$ grade and 22 taxa of the $1^{st}$ grade were found. For the endemic species of Korea, 4 taxa including Cirsium setidens (Dunn) Nakai were confirmed to be distributed mostly on the slope or the cutting area. Among the collected rare plants (11 taxa), there were 1 taxa of endangered species, 4 taxa of vulnerable species and 6 taxa of least concern species. Also, 51 taxa of naturalized plants were identified and 4 taxa of ecosystem disturbance organism designated by the Ministry of Environment were identified. The urbanization index and naturalization index for all species were estimated to be 15.89% and 9.14% respectively. Our survey is expected to be considered as primary data of biological diversity and ecological axis in the DMZ and the western part of the DMZ. According to the results of this study, it is thought to be necessary to establish policies for conservation and protection of the DMZ.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.75-85
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• 2017

A method to estimate hourly temperature profiles on calm and clear nights was developed based on temporal changes of inversion height and strength. A meteorological temperature profiler (Model MTP5H, Kipp and Zonen) was installed on the rooftop of the Highland Agriculture Research Institute, located in Daegwallyeong-myeon, Pyeongchang-gun, Gangwon-do. The hourly vertical distribution of air temperature was measured up to 600 m at intervals of 50 m from May 2007 to March 2008. Temperature and relative humidity data loggers (HOBO U23 Pro v2, Onset Computer Corporation, USA) were installed in the Jungdae-ri Valley, located between Gurye-gun, Jeollanam-do and Gwangyang-si, Jeollanam-do. These loggers were used to archive measurements of weather data 1.5 m above the surface from October 3, 2014, to November 23, 2015. The inversion strength was determined using the difference between the temperature at the inversion height, which is the highest temperature in the profile, and the temperature at 100 m from the surface. Empirical equations for the changes of inversion height and strength were derived to express the development of temperature inversion on calm and clear nights. To estimate air temperature near the ground on a slope exposed to crops, the equation's parameters were modified using temperature distribution of the mountain slope obtained from the data loggers. Estimated hourly temperatures using the method were compared with observed temperatures at 19 weather sites located within three watersheds in the southern Jiri-mountain in 2015. The mean error (ME) and root mean square error (RMSE) of the hourly temperatures were $-0.69^{\circ}C$ and $1.61^{\circ}C$, respectively. Hourly temperatures were often underestimated from 2000 to 0100 LST the next day. When temperatures were estimated at 0600 LST using the existing model, ME and RMSE were $-0.86^{\circ}C$ and $1.72^{\circ}C$, respectively. The method proposed in this study resulted in a smaller error, e.g., ME of $-0.12^{\circ}C$ and RMSE of $1.34^{\circ}C$. The method could be improved further taking into account various weather conditions, which could reduce the estimation error.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.1
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• pp.45-85
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• 2005

The purpose of this paper is to examine the concept of "accident" under the Warsaw system including the Warsaw Convention for the Unification of certain Rules for International Carriage by Air of 1929 and the Montreal Convention of 1999. Most leading case on this subject is Air France v. Saks(470 U.S. 392 (1985)). In the Saks case, it was held that the definition of an accident must be applied flexibly, and most courts have adhered to the definition of accident in Saks case, the application of accident has been less than consistent. However, most cases have held that if the event is usual and expected operation of the aircraft, then no accident has occurred. Courts have also held that where the injury results from passenger's own internal reaction to the usual, normal, and expected operations of the aircraft, it is not caused by an accident. As the Warsaw drafters intended to create a system of liability rules that would cover all hazards of air travel, the carrier should liable for the inherent risks of air travel. It is right in that the carrier is in a better position than the passenger to control the risks during air travel. Most US courts have held that carriers are not liable for one passenger's assault on the other passenger. The interactions between passengers are not part of the normal operations of the aircraft and are therefore not covered by the word "accident" under Art 17 of the Warsaw Convention. It is regretful that the Montreal Convention did not attempt to clarify the concepts of accident in itself. In the light of an emerging tendency to hold the air carrier liable for occurrences that do not exactly go to the operation of the aircraft, it is desirable to regulate that the carrier is liable for an "event" instead of an "accident" in accordance with the Guatemala City protocol.

• Journal of Korean Home Economics Education Association
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• v.21 no.3
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• pp.111-122
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• 2009

This study assessed the levels of knowledge and behavior about food safety, the factors influencing them and the causal relationship between them. The data were collected from 297 high school students in Gyeongbuk region by the self-administered questionnaire. The questionnaire was composed of closed-end questions regarding each respondent's characteristics such as sex and grade, recognition on food safety, concern about hazardous elements towards foods and knowledge and behavior about food safety. The results of this study were as follows. Both levels of knowledge and behavior about food safety were not particularly high. The factors affecting the level of knowledge about food safety were mother's age and concern about hazardous elements towards foods. Grade, father's educational level, concern about hazardous elements towards foods, and the level of knowledge about food safety influenced the level of behavior about food safety. The results of the path analysis showed that grade and father's educational level directly affected the level of behavior about food safety. In addition, concern about hazardous elements towards foods had direct and indirect effect on the level of behavior about food safety On the other hand, the level of knowledge about food safety had an direct influence on the level of behavior about food safety.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1766-1773
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• 2014

The purpose of this research was to scrutinize dieticians' perspective of seafood ingredients prices in school food-service. Suppliers' contract status, seafood ingredient usage and satisfaction, expectations regarding prices of seafood ingredients, and willingness to pay when HACCP is taken into account were studied. Through random sampling, the survey was conducted on 231 dieticians in 11 different educational districts and 12 elementary, six middle, and three high schools. Ultimately, 142 survey responses were taken into account. Data analysis was performed using SPSS v15.0 by descriptive analysis, ${\chi}^2$-test, and t-test. For contracts regarding seafood ingredients, competitive contracts composed 79.7%. Exactly 42.1% responded that contracts were breached, and 60.1% testified that product returns were due to excessive glazing of ingredients. The satisfaction rate of 'hygiene & sanitation of product' was the highest, whereas 'price of product' was the lowest. For 'recontracting intention', 'informal purchasing' showed higher rates compared to 'competitive bidding'. Reflecting upon the six main price factors, 'designation and maintenance of HACCP', 'price of raw seafood ingredients', 'processing costs', 'margin', 'logistic costs', and 'cost of standardizing seafood ingredients', dieticians' perceived 'impact on the anticipated price' on total cost was lower than present counterparts. This implicates that 'impact on the present price' of the six price factors is too excessive, suggesting that many dieticians are unsatisfied with the current prices of seafood ingredients. Furthermore, 52.8% of dieticians stated that the maximum additional payment of HACCP seafood ingredients should be less than 5%. Consequently, this research serves as basic information for reasonable pricing of seafood ingredients and contributes to increased seafood usage by school food-services.