This study attempts a comparison between AHP(Analytic Hierarchy Process) in which the importance weight is structured by individual subjective values and regression model with importance weight based on statistical theory in determining the importance weight of casual model. The casual model is designed by for students’ satisfaction with university, and SERVQUAL modeling methodology is applied to derive factors affecting students’ satisfaction with university. By comparison of importance weights for regression model and AHP, the following characteristics are observed. 1) the lower the degree of satisfaction of the factor, the higher the importance weight of AHP, 2) the importance weight of AHP has tendency to decrease as the standard deviation(or p-value) increases. degree of decreases. the second sampling is conducted to double-check the above observations. This study empirically checks that the importance weight of AHP has a relationship with the mean and standard deviation(or p-value) of independence variables, but can not reveal how exactly the relationship is. Further research is needed to clarify the relationship with long-term perspective.

The paint removal of fighter jets is just as important as the painting, because perfect paint removal ensures the quality of the exterior painting on the aircraft. However, the current conditions for paint removal work of the ROKAF’s are poor. It is identified that the painting process currently implemented by the ROKAF is not only exposed to harmful compounds such as harmful dust and hexavalent chromium, but also consumes a lot of water. Thus, the introduction of advanced facility is considered. This study compares the fighter jets painting removal process currently applied by the Korean Air Force with the improved laser coating removal process of the US Air Force, and conducts an incremental analysis to perform economic analysis for the introduction of advanced facility. Four scenarios were envisioned on the premise of an increase in the number of fighters in the future, incremental analysis shows that laser coating removal method is advantageous in all scenarios. In addition, it is recommended that paint removal cycle keeps the current 12-year and the outsourcing amount to civilian depot is reduced.

Six Sigma is a philosophy and systematic methodology for quality improvement. It encourages continuous quality improvement efforts to achieve the ideal goal of 6σ. Sigma(σ) is a statistic representing the standard deviation of the normal distribution, and 6σ level means a level where the tolerance of the specification is six times the standard deviation of the process distribution. In terms of the defective rate, the 6σ level achieves the 0.002 defectives per one million units. However, in the field, the 6σ level is used in the sense of achieving 3.4 defects per one million opportunities, which shows a large gap from the 6σ level in the statistical viewpoint. This is because field practitioners accept a 1.5σ shift of the mean of process when calculating the defective rate under sigma level. It said that the acceptance of 1.5σ shift of the mean is from experience, but there is no research or theoretical explanation to support it logically. Although it is a non-scientific explanation based on experience, considering that there has been no objection to the 1.5σ shift for a long time and it is rather accepted, it is judged that there is a reasonable basis for the 1.5σ shift. Therefore, this study tries to find a reasonable explanation through detective power of control chart via the run-rules to the 1.5σ shift empirically recognized by practitioners.

The Korean Air-Force aircraft maintenance depot paints the exterior of various aircraft, including high-tech fighters. Aircraft exterior painting is a maintenance process for long-term life management by preventing damage to the aircraft surface due to corrosion. The de-painting process is essential to ensure the quality of aircraft exterior paints. However, because the Korean Air-Force’s de-painting process is currently done with sanding or Plastic Media Blasting (PMB) method, it is exposed to harmful dust and harmful compounds and consumes a lot of manpower. This study compares the de-painting process currently applied by the ROK Air-Force and the more improved process of the US Air Force, and performs economic analysis for the introduction of advanced equipment. It aims to provide information that can determine the optimal time to introduce new facilities through Cost-Volume-Profit (CVP) analysis. As a result of the analysis, it was confirmed that the sanding method had the most economical efficiency up to 2 units per year, the PMB method from 3 to 21 units, and the laser method from 22 units or more. In addition, in a situation where the amount of de-painting work is expected to increase significantly due to the increase in fighters in future, BEP analysis was conducted on the expansion of the existing PMB method and the introduction of a new laser method. As a result of the analysis, it was confirmed that it is more economical to introduce the laser method when the amount of work exceeds the PMB work capacity(18 units per year). The paper would helpful to improve the productivity and quality of the Korean Air Force Aircraft maintenance depot through timely changes of facilities in the workplace in preparation for expansion.

Currently, there are two types of trainer in Korea : basic and advanced. Both models have been in operation for more than 10 years, and compared to the early stage of operation, reliability has gradually improved and failure rates have also entered a trend of stabilization. Therefore, it is necessary to extend the maintenance period considering economic feasibility. This study investigates the three maintenance period calculation methods: NAVAIR 00-25-403 [17], DOD, U.S. [4], CERL and US Army [3], with intention to extend the maintenance period of the trainer from current 200 hours to 400 hours. In addition, the maintenance period was calculated by the three methods with actual operational data. Common standards and procedures were established to apply operational data to the existing maintenance period calculation methods, the required reliability indicators were derived, and the maintenance periods was calculated based on the results, additionally, a review on the field applicability of the three maintenance cycles was conducted. An on-site interviews were conducted with the calculation results, and 11 out of the 15 items were expected to be extended by 400 hours. It was suggested that the remaining 4 items could be extended to 400 hours by supplementing the inspection method through additional analysis such as functional analysis, inspection content verification, and site connection.

This paper investigates the stress-reducing preventive maintenance model through numerical experiments. The preventive maintenance model is used to analyze the relationship between related conditions and variables to gain insight into the efficient operation of the system when performing preventive maintenance in real-world situations. Various preventive maintenance models have been developed over the past decades and their complexity has increased in recent years. Increasing complexity is essential to reflect reality, but recent models can only be interpreted through numerical experiments. The stress-reducing preventive maintenance is a newly introduced preventive maintenance concept and can only be interpreted numerically due to its complexity, and has received little attention because the concept is unfamiliar. Therefore, for information purposes, this paper investigates the characteristics of the stress-reducing preventive maintenance and the relationship between parameters and variables through numerical experiments. In particular, this paper is focusing on the economic feasibility of stress-reducing preventive maintenance by observing changes in the optimal preventive maintenance period in response to changes in environmental stress and the improvement factor. As a result, when either the environmental stress or the improve effect of stress-reducing preventive maintenance is low, it is not necessary to carry out the stress-reducing preventive maintenance at excessive cost. In addition, it was found that the age reduction model is more economical than the failure rate reduction model.

This paper is a follow up to the previous study which reveals that smartphone users are divided into three subcategories according to their usage characteristics. In this paper, these groups are called as ‘general’, ‘entertainment’, and ‘work-assistant’, taking into account their respective characteristics. The ‘general’ is a group whose smartphone usage characteristics are not focused on a specific purpose, the ‘entertainment’ is focused on music, internet, SNS, picture, and e-banking, and the ‘work-assistant’ is on work, GPS, diary. Inter-relation between the importance and satisfaction for the purchase determinants to the groups is investigated. In addition, Kano analysis of quality attributes is also performed, which includes quality type, satisfaction/dissatisfaction index, and PCSI (Potential Customer Satisfaction Improvement) index. The analysis result are as follows. Firstly, inter-relation between importance and satisfaction differs by user group. ‘Internet’, ‘Ease of use’, and ‘Performance’ purchase determinants are evaluated as competitive determinants in ‘work-assistant’ user group. Secondly Kano quality types of quality characteristics also differs by user group. ‘Application’ was classified as an attractive (A) types to ‘entertainment’ group and so on. ‘Internet’ ‘Failure/Bug’, ‘Touch response rate’ and ‘Charging’ are located in ‘Nice’ Region of S-PCSI Diagram and have to be considered as strategic quality characteristics. The results of this study is expected to give some helps in establishing a customer tailored quality strategy.

This paper is an exploratory study to investigate the influence of characteristics of local government web-sites on user satisfaction and trust. The objective of this research is to identify the characteristics of local government web-sites influencing on user satisfaction and trust, and determine how they affect user satisfaction and trust. From the literature review, we identify four characteristics which are expected to influence on user satisfaction: technical, information, customer-oriented, and work-performing characteristics. In addition, we develop research model that the four characteristics are expected to affect user satisfaction and trust via users’ perceived values. The results of the research are as follows. The technical, customer-oriented, and work-performing characteristics significantly affects perceived values, which significantly affected user satisfaction and trust. Perceived value is partially mediated by user satisfaction in affecting user trust. The characteristics of local government web-sites affecting perceived values differed partially by the purpose of visitor. As for the personal goal, the technical, customer-oriented, and work-performing characteristics significantly affect perceived values, with the technical and customer-oriented characteristics having more significant effects. As for the business goal, the technical, information, work-performing characteristics significantly affected perceived values, with information characteristics having more significant effects.

Bamboo sprout powder was added to rice cake in an effort to improve the quality and functional properties of dough. The contents of crude protein and carbohydrates increased as the amount of bamboo sprout powder increased, whereas moisture contents decreased. According to increasing contents of bamboo sprout powder, total amino acid contents significantly increased. Hunter’s L value decreased as contents of bamboo sprout powder increased, whereas sucrose contents increased. Addition of bamboo sprout powder to rice cake increased dietary fiber contents. Sensory scores of rice cake containing 90 g of bamboo sprout powder were the highest of all rice cakes tested. According to the results, adding bamboo sprout powder could improve the quality and sensory characteristics of rice cake.

This study was conducted to investigate the effects of addition of Artemisia annua L. powder in jeonbyeong. Contents of crude ash increased as the amount of Artemisia annua L. powder increased, whereas crude fat contents decreased. According to increasing contents of Artemisia annua L. powder, total amino acid contents significantly increased. Hunter’s L value increased as contents of Artemisia annua L. powder increased, whereas total free sugar contents decreased. Addition of Artemisia annua L. powder to jeonbyeong increased dietary fiber contents. The sensory score of jeonbyeong containing 100 g of Artemisia annua L. powder was the highest of all jeonbyeong tested. According to the results, addition of Artemisia annua L. powder could improve the quality and sensory characteristics of jeonbyeong.

In aerospace industry, MTBF(Mean Time Between Failure) and MFTBF((Mean Flight Time Between Failure) are generally used for reliability analysis. So far, especially to Korean military aircraft, MFTBF of avionic equipments is predicted by MIL-HDBK-217 and MIL-HDBK-338, however, the predicted MFTBF by military standard has a wide discrepancy to that of real-world operation, which leads to overstock and increase operation cost. This study analyzes operational data of avionic equipments. Operational MFTBF, which is calculated from operational data, is compared with predicted MFTBF calculated conventionally by military standard. In addition, failure rate trend is investigated to verify reliability growth in operational data, the investigation shows that failure rate curve from operational data has somewhat pattern with decreased failure rate and constant failure rate.

This paper is a case study of reliability assessment with field warranty data of Clutch Master Cylinder(CMC) in hydraulic clutch system. We estimate lifetime distribution using field warranty data which contain much useful information for understanding reliability of the system in the real-world environments. However, the estimated parameters are far from existing reference values, which seems to be caused right censored field warranty data. To modify the parameters, we use the information of the durability test which is performed to verify that the lifetime of the item meets the required level. After that, we can observe that the modified parameters are closer to the existing reference values. This case study shows a possible idea to supplement lack of right censored field warranty data and its applicability

This study was conducted to observe the fermentative quality and anthocyanin content in whole crop colored barley silage during storage periods and anthocyanin stability in in vitro ruminal fluid. Silages of colored barley cultivar “Boanchalbori” and normal barley cultivar “Yuyeonbori” were stored during 0, 2, 4, 6, and 12 months. The in vitro ruminal fluid was fermented for 0, 6, 12, 24, and 48 hrs. For the feed value, crude protein of colored barley silage was slightly increased in the silage compared to that of normal barley silage, and being increased up to 2 months after ensiling and thereafter maintained at the similar level. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of both the barley significantly increased by prolonged storage of 2 months (p<0.05), but they were maintained at the constant level after 2 months of storing silage. Whereas TDN (total digestible nutrients) contents of them were decreased by the prolonged storage of 2 months (p<0.05), then maintained at the constant levels. The fermentative quality and pH values in both the barley silages were slightly decreased during the storage time. Lactic acid and acetic acid contents were increased during prolonged storage period, but not significantly different among treatments. Butyric acid was not detected. In the colored barley silage, pH value showed slightly lower compared to that of the normal barley silage but not significant, and lactic acid content was significantly higher than the normal barley silage (p<0.05). The total anthocyanin content in the whole crop colored barley silage decreased to 42% after 2 months of ensilage, however maintained at the constant level until 12 months of ensilage. In the case of anthocyanin stability on in vitro ruminal fluid digestion, the pH value of the ruminal fluid was slightly lower at 6, 12, 24, 48h incubation time and the content of anthocyanin was at similar levels. These results indicated that the colored barley showed higher fermentation quality, and total anthocyanin content was maintained stable at 42% level of the first value in storing silage. As the anthocyanin had higher stability in the ruminal fluid, the colored barley has a potential as functional feeds for Ruminants.

This study was to investigate pregnancy rate of IVM/IVF/IVC Korean cattle (registered in government) embryos according to transport time course. For the production of embryos, oocytes recovered from slaughtered excellent grade cow and highly motile frozen‐thawed bull semen (purchased from LIMC, KPN#497) was used. In vitro produced embryos were cultured in CR1aa medium for 8 days and some of them were frozen. The rate of average cleavage (>2‐cell) was 83.0% (308/371) and blastocyst rate at day 8 was 34.7% (107/308). Among in vitro produced blastocyst embryos at day 8, most healthy embryos were freshly transferred on production day and some frozen embryos were direct transferred on appropriate day. These embryos were produced in a laboratory, embryo transfer (ET) was planned in 10 areas of the remote island (Jeju) from the laboratory by airplane. Thus, we examined the pregnancy rate in recipient cow according to embryo of transport time course before ET. From embryo transferred 44 recipient cows, overall pregnancy was 40.9% (18/44), these 18 cows were all calved [single, 94% (17/18); twin, 6% (1/18)] and total embryo implantation rate was 26% (19/66). Comparing transport time in the base of 6 hr, pregnancy rate in ET group required less 4 hr (60%, 9/15) was significantly higher than that required more 6 hr (26.3%, 5/19). In direct ET of freezing embryos, the pregnancy rate was 40% (4/10). However, it was difficult to find the meaning of temperature, pH and corpus luteum quality of recipients on comparison of pregnancy rate. When the cell death level of embryos according to storage time in thermos (straw container) before ET was measured by TUNEL staining, apoptotic index was increased with storage time‐dependent. These results demonstrated that long distance transfer of IVM/IVF/IVC embryos is possible and the time of embryo transport is very important for the pregnancy rate on field trial.

Background : Cirsium plants have been used for perennial edible plants and grow wild in the mountainous regions of Korea, including Cirsium setidens and C. pendulum. In particular, C. setidens is commonly called 'gondre', and it has been used medicinally for diseases such as hematuria, hepatitis and hypertension. Hairy roots cultivation can be used as a method for increasing production through mass culture of medicinal plants, and elicitors such as methyl jasmonate (MeJa) can be treated to increase the content of certain useful ingredients. In this study, the hairy root was derived from the leaf tissues of C. setidens and C. pendulum, and the HPLC pattern was compared by MeJa treatment. Methods and Results : Agrobacterium rhizogenes R1000 was used to induce hairy roots in 1/2× MS medium. In addition, the hairy roots was treated with MeJa for different time (0, 1, 2, 5, 10, 24, 48, 72 h) and with various concentrations (0, 10, 50, 100, 200, 300 μM). The HPLC pattern changes were analyzed by on-line HPLC-ABTS. Four new peaks were observed in both Cirsium setidens and C. pendulum hairy roots, all of which showed antioxidant activity. In the case of C. pendulum, chlorogenic acid content was about 4 times higher than that of leaves. These peaks, including chlorogenic acid, were all affected by MeJa treatment. Conclusion : Four peaks were detected in the hairy roots of C. setidens and C. pendulum not in the leaves, and they were confirmed to be affected by the treatment of MeJa. It is necessary to clarify the structure through the subsequent compound separation.

The purpose of this study was to determine the optimum amount of Artemisia annua L. powder for adding rice flour. The A. annua powder was added to the rice flour at ratios of 1% (30 g/3 kg), 2% (60 g/3 kg), 3% (90 g/3 kg, w/w). As the amount of A. annua powder in rice cake dough increased, carbohydrate, ash content, total amino acid, and dietary fiber contents increased whereas the moisture content decreased. Hunter’s L value decreased as A. annua powder content increased. On the contrary, the a- and b values increased. The sensory score of the rice cakes containing 30 g of A. annua powder was the highest of all the rice cakes tested. Based on these results, adding A. annua powder could improve the quality and sensory characteristics of rice cake.

죽순분말을 첨가한 전병을 제조하여 첨가 수준별 품질특성을 조사하였다. 죽순분말 첨가 전병의 일반성분 중 조단백질, 식이섬유와 회분의 경우 죽순분말 첨가량이 증가할수록 높아지는 경향을 보였고 조지방은 감소하였다. 유리아미노산 함량의 경우 죽순분말을 첨가할수록 증가하는 결과를 보였다. 색도에서 명도를 나타내는 L값은 죽순 분말 첨가량이 높아지면서 증가하였고, 무첨가구 시료와 타 시료간의 색차값을 비교한 ΔE 값의 변화는 죽순 분말 100g 첨가구가 4.58로 나타나 죽순 분말 첨가가 전병 고유의 색에 영향을 주는 것으로 나타났다. 유리당 함량은 죽순분말을 첨가하면서 다소 감소하는 것으로 나타났다. 관능에 따른 시료별 선호도 결과 죽순 300 g 첨가 시료가 색(color), 향미(flavor), 맛(taste), 식감(chewiness) 모두 가장 높은 값을 나타냈다. 전반적 기호도와 다양한 관능검사 결과를 종합하여 볼 때 전병에 첨가하는 죽순분말의 적정 비율은 300 g 수준이 가장 좋은 것으로 나타났다.

Fermented soybean food is one of most economical and health food due to its valuable nutritional and medicinal attributes and have been consumed for centuries as flavoring ingredient in Korea. On fermented soybean food such as doenjang, aroma compounds are important property because they determine taste and grade of fermentation. This study investigated variety of aroma compounds of doenjang made from different soybean genotypes. Aroma compounds in twelve different doenjang made from two cultivar (Daewon and Taekwang) and ten elite lines were extracted by steam distillation extraction (SDE) method and analyzed by gas chromatography/mass spectrometry (GC/MS). Aroma compound were detected over 80 kinds in eight samples (Daewon, Taekwang, MY177, MY187, MY189, MY192, MY204 and MY205) and under 70 kinds in four samples (yeonchun1, MY188, MY203 and MY206). Among the detected aroma components, 47 compounds were assigned as aromatic compounds (21), long chain fatty acid (13), short chain fatty acid (5) and others (8) by the computer library (Wiley 7n program). The major aroma compounds in twelve different doenjang were benzaldehyde, benzeneacetaldehyde, 2-methoxy-4-vinylphenol, pyrazine type compounds, cysteaminesulfonic acid, palmitic acid, oleic acid and linoleic acid. Each doenjang made by same condition (microbe, temperature, aging time and etc) had a difference in ratio and variety of aroma compounds due to different components having soybean genotype.