• Journal of Embryo Transfer
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• v.30 no.3
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• pp.149-159
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• 2015

This study was designed to know the possibility in repeat uses of elite donor cows for getting mass production of OPU-derived embryo production (OPU-IVP). Ultrasound transvaginal ovum pick-up (OPU) performed in 6 Korean native cows was aged 4 to 10 years old. The aspiration of immature oocytes for OPU derived embryo was carried out 2 times per week, and OPU-IVP of $1^{st}$ period was carried out 22~48 sessions from each donors. And the break time for OPU-IVP of $2^{nd}$ period after $1^{st}$ OPU from each donors were 2~25 months. The OPU-IVP of $2^{nd}$ period each donors conducted total 15~65 times for 2~8 months by an ultrasonographic, was guided follicular aspiration system. The average numbers of collected oocytes, grade 1 + grade 2(G1+G2) oocytes and cleavage embryo from $1^{st}$ period OPU-IVP were significantly differences between donors (p<0.05). Total collected oocytes of donor D were significantly higher compared with donors of A, B, C, E and F (average 17.0 per session vs. 11.2, 10.1, 8.5, 10.2 and 9.6; p<0.05) and also oocytes of G1+G2 were significantly higher compared with r A and D and subsequently to donors of B, C, E and F (average 7.9 and 8.5 per session vs. 5.0, 2.7, 6.0 and 1.6; p<0.05). Cleavage rate of donor D was significantly higher compared with donors of A, B, C, E and F (average 13.1 per session vs. 10.1, 9.1, 6.9, 8.9 and 6.7; p<0.05). The average numbers of OPU-IVP for $1^{st}$ period was significantly higher from donors of B, D and E than those from donors of A, C and F (average 6.5, 7.1 and 6.5 per session vs. 3.5, 4.2 and 2.8; p<0.05). The possibility investigation of $2^{nd}$ OPU-IVP was carried out after 2~25 months rest periods from $1^{st}$ period OPU session. Total average numbers of collected oocytes, cleavages and blastocyst development rates were significantly higher from $1^{st}$ period OPU compared with $2^{nd}$ period one (p<0.05). The OPU-IVP efficiency by break for more embryo production from elite cow was analysis comparing without rest of donor A, under 6 months rest period as B and over 6 months rest period as C and then the average numbers of collected oocytes, cleavages and blastocysts were significantly higher from A group (11.8, 9.5 and 5.2 per session) than those from B and C groups (7.9, 6.2 and 2.6 vs. 9.2, 7.5 and 3.9, p<0.05), and also C group was significantly higher than B group. In conclusion, $1^{st}$ period OPU-IVP was more efficient compared with $2^{nd}$ period repeated uses of donor, and the break times for additional production of embryo on donor were needed more than over 6 months after $1^{st}$ period OPU-IVP. This repeating uses of elite donor cows given more emphasis for getting the opportunity on mass production of elite cow OPU-IVP embryo should be increased G1+G2 possibility of genetic improvement of livestock within short period.

• Journal of Haehwa Medicine
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• v.2 no.2
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• pp.219-246
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• 1993

In 1991, Obesity rate of South Korea has reached to 18.7%. Because of economical development, the pattern of diet is exchanged from carbohydrate to rich protein and fat. The more problem is not only obesity of adult but also one of little child. Obesity is induced to diabetes mellitus, hypertension, artherosclerosis, hyperlipoidemia. heart and C.V.A disease, etc. In Woman, special important ploblem is the complex of beauty about Woman's figure. In Oriental Medicine, the factor of obesity is mainly regarded as dampness. And there are many treatments and methods to body weight loss, but obesity patients dislike to use them because of their side effects and inconvenience, intolerance. Now ear acupuncture is applied on so many disease because of its easy handly, non-side effect and high efficiency in clinics. Here obesity acupuncture is used to ear and whole body acupuncture. Because they react eachother for lack point. Therefore, in order to investigate the effect of obesity acupuncture and develop non-drug, non-starvation etc, we analyzed 453 the cases of body weight loss patients treated with ear and whole body acupuncture in Oriental Medicine Hospital of Jeon-Ju Woo-Sug University from April.1.1992. to March.17. 1993. The results were summarized as follows. 1. Distribution of sex ; male (4.4%), Female(95.6%) 2. Distribution of age in descending order ; 30s, 20s, 40s, 10s, 50s, below 10s, abowe 60s. The 20s-30s are group made up 60.7% of the group. 3. Distribution of occupation in descending order; housewife, student, service, salaried, merchant, teacher, farmer, inoccupation. 4. Distribution of human coporal constitution in descending order : Tae-Eum-In, So-Eum-In, So-Yang-In. 5. Distribution of body height and weight, 155-164cm ; 71.1%, 60-70kg, 74.6% are majority. 6. Distribution of weight variation, 2-6kg(71.0%) is majority, also 13-14kg(0.4%). 7. Distribution of duration in descending order ; 1-3 years, 3-6 years, 1-12months, above 10 years but in success, 1-12 months, 1-3 years, 3-6 years, above 10 years. Therefore, we know that the shorter duration of obesity is, the more loss of body weight. 8. Past experiences to body weight loss; Yes(69.5%), No(30.5%). The success rate accordant with the past temporary experiences shows that the cases without experience is higher than the ones with experience. 9. In distribution of times(treatments), 10 times is top. The rate of body weight loss is the highest in 14 times. Therefore, I think that one would need at least 10 times. in order lose body weight 10. Distribution of body weight variation in treatments times is at 2 times(3-4kg loss), and surprisingly is 14kg loss at above 15 times. 11. Distribution of symptoms improvement, in descending order ; heavy sense in body, dec. of appetite, inc.of exercise, lumbago, edema, knee pain, inc.of urine, inc. of fullness sense, thirsty, disease of gynecology, white tung, chest burning, heart burning, dec.of tobacco, drink taste. motion sickness, allergy, water eczema, arthma, belching. 12. Distribution of snack; Yes(87.4%), No(78.6%) 13. Distribution of exercise; Yes(21.4%), No(78.6%) 14. Distribution of sleeping times, above 7 hours(79.0%) 15. Distribution of the reason to body loss, the complex of beauty(68.7%) is top. 16. Distribution of side effect in obesity acupuncture, constipation (17.4%) is top. 17. Distribution of method in body weight loss ; dietary treatment (31.1%), sauna(26.7%), exercise(19.7%), the center of body weight loss (15.0%) herb-med and starvation treatments (5.1%), hand-finger acupuncture (hand-foot acupuncture) is 1.6%, diet pill(0.3%), etc(0.6%).

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.1-10
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• 2010

Objectives : It is necessary that the international classification of diseases (ICD) be examined in order to comprise the third revision of the Korean Classification of Disease on Oriental Medicine (KCD-OM) and disease classification in the oriental internal medicine field. It is essential that the selection, classification and definition of disease and pattern names of oriental concepts in internal medicine be clear. Since 2008, the fifth revision of the Korean Classification of Disease (KCD-5) has been used in Korea. It was required to use the reference classification from the Oriental medicine area based on the ICD-10. Methods : In this review, the necessity for, meaning of and content of the third revision are briefly described. The ICD system was reviewed and KCD-OM was reconstructed. How diagnosis in the oriental internal medicine area had changed is discussed. Review and Results : In 1973, the disease classification of oriental medicine was established the basis on the contents of Dongeuibogam. It was irrespective of the ICD. As to the classification system in the Oriental internal medicine field, systemic disease was comprised of wind, cold, warm, wet, dryness, heat, spirit, ki, blood, phlegm and retained fluid, consumptive disease, etc. Diseases of internal medicine comprised a system according to the five viscera and the six internal organs and followed the classification system of Dongeuibogam. The first and second revisions were of the classification system based on the curriculum in 1979 and 1995. In 1979, in the first revision, geriatric disease and idiopathic types of disease were deleted, and skin disease was included among surgery diseases. This classification was expanded to 792 small classification items and 1,535 detailed classification items to the dozen disease classes. In 1995, in the second revision, it was adjusted to 644 small classes and 1,784 detailed classification items in the dozen disease classes. KCD-OM3 did KCD from this basis. It added and comprised the oriental medical doctor's concept names of diseases considering the special conditions in Korea. KCD-OM3 examined the KCD-OMsecond revised edition (1994). It improved the duplex classification, improper classifications, etc. It is difficult for us to separate the disease names and pattern names in oriental medicine. We added to the U code and made one classification system. By considering the special conditions in Korea, 169 codes (83 disease name codes, 86 pattern name codes) became the pre-existence classification and links among 306 U codes of KCD-OM3. 137 codes were newly added in the third revision. U code added 3 domains. These are composed of the disease name (U20-U33, 97 codes), the disease pattern name (U50-U79, 191 codes) and the constitution pattern name of each disease (U95-U98, 18 codes). Conclusion : The introduction of KCD-OM3 conforms to the diagnostic system by which oriental medical doctors examine classes used with the basic structure of the reference classification of WHO and raises the clinical study and academic activity of the Korean oriental medicine and makes the production of all kinds of nation statistical indices possible. The introduction of KCD-OM3 promotes the diagnostic system by which doctors of Oriental medicine examine classes using the association with KCD-5. It will raise the smoothness and efficiency of oriental medical treatment payments in the health insurance, automobile insurance, industrial accident compensation insurance, etc. In addition, internationally, the eleventh revision work of the ICD has been initiated. It needs to consider incorporating into the International Classification of Diseases some of every country's traditional medicine.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.84-91
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• 2020

The efficiency of the synthetic magnesium silicate used in basic polyols and edible oil purification is evaluated by its purification ability and filtration rate and is affected by the particle size and surface area of magnesium silicate. In this study, it was investigated the change on the particle size of magnesium silicate was influenced by the reaction temperature, injection rate, injection order (Si, Mg) and Mg/Si reaction mole ratio. The synthesized magnesium silicate was compared and analyzed for the synthesis, grinding, and refining processes. In the synthesis process, the reaction temperature and feed rate did not affect the average particle size change of magnesium silicate, while the reaction molar ratio of Mg / Si and the order of injection acted as main factors for the change of average particle size. The average particle size of magnesium silicate increased by 8.7 ㎛ from 54.4 ㎛ to 63.1 ㎛ at Mg injection when Mg molar ratio increased from 0.125 to 0.500, and increased by about 4.8 ㎛ from 47.3 ㎛ to 52.1 ㎛ at Si injection. The average particle size according to the order of injection was 59.1 ㎛ for Mg injection and 48.4 ㎛ for Si injection and the difference was shown 10.7 ㎛, therefore the filtration rate was about 2 times faster under the condition of Mg injection. That is, as the particle size increases, the filtration time is shortened and washing filtration rate can be increased to improve the productivity of magnesium silicate. The cake form of separated magnesium silicate after filtration becomes a solid through drying process and is used as powdery adsorbent through the grinding process. As the physical strength of the dried magnesium silicate increased, the average particle size of the powder increased and it was confirmed that this strength was affected by the reaction molar ratio. As the reaction molar ratio of Mg / Si increased, the physical strength of magnesium silicate decreased and the average particle size after grinding decreased by about 40% compared to the average particle size after synthesis. This reduction of strength resulted in an improvement of the refining ability due to the decrease of the average particle size and the increase of the amount of fine particle after the pulverization, but it resulted in the decrease of the purification filtration rate. While the molar ratio of Mg/Si was increased from 0.125 to 0.5 at Mg injection, the refining ability increased about 1.3 times, but the purification filtration rate decreased about 1.5 times. Therefore, in order to improve the productivity of magnesium silicate, the reaction molar ratio of Mg / Si should be increased, but in order to increase the purification filtration rate of the polyol, the reaction molar ratio should be decreased. In the synthesis parameters of magnesium silicate, the order of injection and the reaction molar ratio of Mg / Si are important factors affecting the changes in average particle size after synthesis and the changes of particle size after grinding due to the changes of compressive strength, therefore the synthetic parameter is an important thing that determines productivity and refining capacity.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.4
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• pp.3170-3180
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• 1973

This study of the subject will review past and present irrigation development in Korea. Particular attention will be given to water pricing structure and a case study on the purpose of rational operation and management of irrigation water and organizations, and the optimum irrigation water and organizations, and the optimum irrigation water fee inorder to reduce farmers burden and to rationalize the farmland associations management so as to achieve development of the rural environment. In 1971, the reservoir of the Farmland Improvement A sociation (FIA) produced only 775 millison $m^3$ of irrigation water or 77% of planned capacity of 1,015 million $m^3$. It was caused by inefficient maintenance of irrigation facilities; for instance, about 21% of reservoirs, pumping stations and weirs in Korea have been silted by soil erosion which hinder to water production according to an ADC survey. The first Irritation Association was established in 1906, whcih was renamed the Farmland Assoeiation by the Rural Development Enouragement Law in 1970. By the end of 1971, 411,000 ha of rice paddies were under the control of 267 associations nationwide. The average water price assessed by Associations nationwide rose from 790 won per 0.1 ha. in 1966 to 1,886 won in 1971. The annual growth rate was 20%. The highest water price in 1971 was 4,773 won her 0.1 ha. and the lowest was 437 won. This range was caused by differences in debt burden, geographic conditions and management efficiency among the Associations. In 1971, the number of Associations which exceeded the average water price of 1,886 won per 0.1 ha. was 144, or 55.1% of all Association. In determination of water price, there are two principles; one is determined by production cost such as installation cost of irrigation facilities, maintenance cost, management cost and depreciation ect. For instance, the Yong San River Development project was required 33.7 billion won for total construction and maintenance cost is 3.1 billion won for repayment, maintenance and management cost per year. The project produces 590 million $m^3$ of irrigation water annually. Accordingly, the water price per $m^3$ is 5.25 won. The other principle is determined by water value in the crop products and in compared with production of irrigated paddy and non-irrigated paddy. By using this method, water value in compared with paddy rice vs. upland rice(Average of 1967-1971) was 14.15 won per $m^3$ and irrigated paddy vs. non-irrigated paddy was 2.98 won per $m^3$. In contrast the irrigation fee in average association of 1967-1971 was 1.54 won per $m^3$. Accordingly, the current national average irrigation fee(water price) is resonable compared with its water value. In this study, it is found that the ceiling of water price in terms of water value is 2.98 won per $m^3$ or 2,530 won per 0.1 ha. However, in 1971 55% of the associations were above the average of nationwide irrigation fees. which shows the need for rationalization of the Association's management. In connection with rationalization of the Association's management, this study recommends the following matters. (1) Irrigation fee must be assessed according to the amount of water consumption taking intoaccount the farmer's ability. (2) Irrigation fee should be graded according to behefits and crop patterns. (3) Training personnel in the operation and procedures of water management to save O&M costs. (4) Insolvent farmland association should be integrated into larger, sound associations in the same GUN in order to reduce farmers' water cost. (5) The maintenance and repair of existing irrigation facilities is as important as expansion of facilities. (6) Establishment of a new Union of Farmland Association is required to promoted proper maintenance and to protect the huge investment in irrigation facilities by means of technical supervision and guidance.

• Journal of Science Education
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• v.34 no.2
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• pp.291-305
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• 2010

The aim of this study was to survey the perceptions of the elementary school teachers on the smallscale chemistry(SSC) following its training session. The teachers participating in the survey were 266 teachers in the Gyeongnam province. They were given a questionnaire that focused on the nine areas of the SSC: Needs for the teacher training and its application, its benefits, issues of safety and danger as well as treatment of environmental pollution, its economic efficiency and the development of investigative skills. The designed questionnaire was checked by an authority, and the responses to each question were tallied and analyzed. The results are as follows. The biggest problems of the traditional experimental methods as rated by the teachers were, in the order of importance, the preparation time, the legal liability of teachers for the safety and accidents, financial issues, disposal of the experimental wastes and the lack of relevant data. Since most of the teachers had not experienced the SSC lab programs in the field, they responded positively to the questions of need for its introduction and training. The implementation of the experimental SSC lab programs should proceed in the following order: introduction into the textbook, teacher training program, after-school education and the invitation of instructors. The most useful materials for the SSC program were CDs, videos, books and various printed materials, in that order. The responses regarding benefits of the SSC program included its simplicity, convenience, time savings, diversity, qualitative and quantitative aspects, integration into the regular class and use of toys. In particular, the teachers mentioned the increased safety due to the small amount of experimental reagents needed and the durability of plastic instruments. The familarity from the use of everyday tools as well as easy access to and the low-cost of the instruments were other important benefits. The teachers in general rated the educational content of the program highly, but many also found it to be average. Some pointed out the lack of sufficient discussion due to the individual or pair groupings as a potential shortcoming. The potential for development of problem solving ability and improvement of skills was rated positively. The number of teacher who rated the development of creativity positively was just over the half. As for the area of improving investigative skills, many found its assessment difficult and confusing because of the lack of its systemic definition and categorization. Based on the findings of this study, I would like to recommend the application and a wider dissemination of the small-scale chemistry lab program into the elementary school science curriculum.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.4
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• pp.60-72
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• 2019

The purpose of this study was to identify detailed factors that affect visitor satisfactions of the plants on display, environments of pedestrian road and facility of each theme garden by conducting a survey of visitors to Jade Garden. The 400 data including 100 copies per theme garden were used for statistical analysis. The statistical techniques used in the survey analysis include multi-regression analysis, t-test, and analysis of variance(ANOVA). As a result of the analysis, most of theme gardens tended to have the greatest impact on the satisfaction of the plants on display and the lowest level of facility satisfaction. According to detailed factors analysis of the satisfaction of plants on display satisfaction of plant diversity and the method of plant display were most affected in most of the theme gardens. Among them, promoting the satisfaction of plant diversity is necessary to plant various species, but in case of Ginkgo Maze Garden, a type of tree community as one tree(Ginkgo biloba), the satisfaction of plants diversity did not show a rising-up value. Therefore, it was confirmed that the appropriate degree of plants diversity depends on the theme or environment of the garden. In the case of the pedestrian-road-satisfaction, the width of the pedestrian road was the most affected, It was analyzed that whether the point of intersection can be easily available during peak season has a significant impact on the satisfaction of visitors. In the case of facility satisfaction, it was analyzed that the presence of rest and convenience facilities had the most direct influence on visitors, so the facility diversity had the greatest influence. Therefore, it is necessary to more systematically categorize and consider the influential detailed factors such as plants diversity and methods of plant display, width of pedestrian road and facilities diversity for the management and development of the arboretum.

• The Korean Journal of Air & Space Law and Policy
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• v.34 no.1
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• pp.3-38
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• 2019

In 1984, Congress enacted a new measure of administrative sanctions which is a civil money penalty program for violations of Aviation Act and its implementing regulations. This civil money penalty system has been in operations in lieu of suspending or revoking certificates issued by Korean government, Ministry of Land, Infrastructure, and Transport. According to the rules of Aviation Business Act or Aviation Safety Act, where the Minister of Land, Infrastructure and Transport should order an air carrier to suspend operation because of her violation under certain rules, in which case the suspension of operation is likely to cause serious inconvenience to consumers of air transport services or to harm public interest, the Minister of the department may impose an administrative monetary penalty in lieu of the suspension of operation. In this regard, airline related civil money penalties are somewhat different from those of fair trade, which is the origin of the money penalties system in Korea. Civil money penalties in the field of fair trade are imposed on executive duty violations that undermine the value of the market economy order, and focus on reimbursement of profits due to violations and compensation for unfair spending by consumers. However, in the aviation sector, breach of duty by a business operator does not simply cause the property loss of the public, but it has a direct impact on life or property of the public. In this respect, aviation penalties are more likely to be administrative sanctions or punitive measures than refunds of unfair benefits, compared to penalties in the field of fair trade. In general, civil money penalties have been highly preferred as administrative sanctions because they are subject to investigations by administrative experts and thus, efficiency can be ensured and execution is quicker than judicial procedures. Moreover, in Korea, because punitive civil damages cannot awarded by the courts, the imposition of civil money penalties is recognized as a means of realizing social justice by recognizing the legal feelings of the people. However, civil money penalties are administrative sanctions, and in terms of effectiveness, they are similar to criminal fines, which are a form of punishment. Inadequate legislation and operation of penalties imposition may cause damage to the value of Constitution. Under the above recognition, this paper has been described for the purpose of identifying the present status of the civil money penalties imposition system and operating status in the area of air transport under the laws and regulations in Korea. Especially, this paper was focused on exploring the problem and improvement direction of Korean system through the comparative study with foreign laws and regulations.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.100-101
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• 2012

The plasma damage free and room temperature processedthin film deposition technology is essential for realization of various next generation organic microelectronic devices such as flexible AMOLED display, flexible OLED lighting, and organic photovoltaic cells because characteristics of fragile organic materials in the plasma process and low glass transition temperatures (Tg) of polymer substrate. In case of directly deposition of metal oxide thin films (including transparent conductive oxide (TCO) and amorphous oxide semiconductor (AOS)) on the organic layers, plasma damages against to the organic materials is fatal. This damage is believed to be originated mainly from high energy energetic particles during the sputtering process such as negative oxygen ions, reflected neutrals by reflection of plasma background gas at the target surface, sputtered atoms, bulk plasma ions, and secondary electrons. To solve this problem, we developed the NBAS (Neutral Beam Assisted Sputtering) process as a plasma damage free and room temperature processed sputtering technology. As a result, electro-optical properties of NBAS processed ITO thin film showed resistivity of $4.0{\times}10^{-4}{\Omega}{\cdot}m$ and high transmittance (>90% at 550 nm) with nano- crystalline structure at room temperature process. Furthermore, in the experiment result of directly deposition of TCO top anode on the inverted structure OLED cell, it is verified that NBAS TCO deposition process does not damages to the underlying organic layers. In case of deposition of transparent conductive oxide (TCO) thin film on the plastic polymer substrate, the room temperature processed sputtering coating of high quality TCO thin film is required. During the sputtering process with higher density plasma, the energetic particles contribute self supplying of activation & crystallization energy without any additional heating and post-annealing and forminga high quality TCO thin film. However, negative oxygen ions which generated from sputteringtarget surface by electron attachment are accelerated to high energy by induced cathode self-bias. Thus the high energy negative oxygen ions can lead to critical physical bombardment damages to forming oxide thin film and this effect does not recover in room temperature process without post thermal annealing. To salve the inherent limitation of plasma sputtering, we have been developed the Magnetic Field Shielded Sputtering (MFSS) process as the high quality oxide thin film deposition process at room temperature. The MFSS process is effectively eliminate or suppress the negative oxygen ions bombardment damage by the plasma limiter which composed permanent magnet array. As a result, electro-optical properties of MFSS processed ITO thin film (resistivity $3.9{\times}10^{-4}{\Omega}{\cdot}cm$, transmittance 95% at 550 nm) have approachedthose of a high temperature DC magnetron sputtering (DMS) ITO thin film were. Also, AOS (a-IGZO) TFTs fabricated by MFSS process without higher temperature post annealing showed very comparable electrical performance with those by DMS process with $400^{\circ}C$ post annealing. They are important to note that the bombardment of a negative oxygen ion which is accelerated by dc self-bias during rf sputtering could degrade the electrical performance of ITO electrodes and a-IGZO TFTs. Finally, we found that reduction of damage from the high energy negative oxygen ions bombardment drives improvement of crystalline structure in the ITO thin film and suppression of the sub-gab states in a-IGZO semiconductor thin film. For realization of organic flexible electronic devices based on plastic substrates, gas barrier coatings are required to prevent the permeation of water and oxygen because organic materials are highly susceptible to water and oxygen. In particular, high efficiency flexible AMOLEDs needs an extremely low water vapor transition rate (WVTR) of $1{\times}10^{-6}gm^{-2}day^{-1}$. The key factor in high quality inorganic gas barrier formation for achieving the very low WVTR required (under ${\sim}10^{-6}gm^{-2}day^{-1}$) is the suppression of nano-sized defect sites and gas diffusion pathways among the grain boundaries. For formation of high quality single inorganic gas barrier layer, we developed high density nano-structured Al2O3 single gas barrier layer usinga NBAS process. The NBAS process can continuously change crystalline structures from an amorphous phase to a nano- crystalline phase with various grain sizes in a single inorganic thin film. As a result, the water vapor transmission rates (WVTR) of the NBAS processed $Al_2O_3$ gas barrier film have improved order of magnitude compared with that of conventional $Al_2O_3$ layers made by the RF magnetron sputteringprocess under the same sputtering conditions; the WVTR of the NBAS processed $Al_2O_3$ gas barrier film was about $5{\times}10^{-6}g/m^2/day$ by just single layer.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.4
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• pp.307-319
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• 2010

Objective: Vitrification requires a high concentration of cyroprotectant (CPA) and an elevated cooling speed to avoid ice crystal formation. We have evaluated the effect of different combinations of cooling rate and CPA on embryonic integrity (developmental competence) in order to increase the efficiency of vitrification without impairing embryo viabilit. We hypothesized that the combination of CPA or the increase of cooling rates can reduce the concentration of toxic CPA for vitrification. As consequently, we performed experiments to evaluate the effect of various composition of CPA or slush nitrogen ($SN_2$) on the mouse embryonic development following vitrification using low CPA concentration. Methods: Vitrification of mouse embryos was performed with EM grid using liquid nitrogen ($LN_2$) or $SN_2$ and different composition of CPAs, ethylene glycol (EG) and dimethylsulfoxide (DMSO). After vitrification-warming process, their survival and blastocyst formation rates were examined. For analyzing long-term effect, these blastocysts were transferred into the uterus of foster mothers. Results: Survival and blastocyst formation rates of vitrified embryos were higher in EG+DMSO group than those in EG only. Furthermor, the group using $SN_2$ with a lower CPA concentration showed a higher survival of embryos and developmental rates than group using $LN_2$. Conclusion: The combination of EG and DMSO as CPAs may enhance the survival of mouse embryos and further embryonic development after vitrification. $SN_2$ can generate high survival and developmental rate of vitrified/warmed mouse embryos when a lower concentration of CPA was applied. Therefore, these systems may contribute in the improvement of cryopreservation for fertility preservation.