• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.47
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• pp.1-10
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• 1998

Testing high reliability devices under nomal operating condition is difficult, because the devices are not likely to fail in the relatively short time available for tests. For most applications it is necessary to accelerate the causes of failure by increasing a stress above its nomal value. Previous accelerated life test(ALT) plans have shown how to find optimum allocation, lowest stress and sample size subject to minimizing the variance of mean life estimator. In these ALT plans, the highest acceptable test-stress was assumed to be specified in advance by the experimenter but there is no guidance for selecting it. This assumption is, however, inappropriate for many applications. Testing devices at too-high stress levels can invalidate the extrapolation model, or introduce failure mechanisms that are not anticipated under nomal operating conditions. In this paper, we propose new 4:2:1 compromise plans using Min-Max method to minimize this risk and present minimized test-stress levels(max, middle, min), and find sample allocation based on Min-Max 4:2:1 compromise plans. In result, we compare previous 4:2:1 compromise plans specified maximum test-stress with Min-Max 4:2:1 compromise plans minimized maximum test-stress.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.863-872
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• 2010

The overall effects of three different beers on white bread were examined in terms of mixograph, pH, fermentation rate, TPA, crumbScan, colorimeter, sensory evaluation, and the hardness of bread through different storage times (0, 1, 2, 3 days), and texture as measured by texture analyzer. According to mixograph, the control (CON), black beer stout (BOB) and Asahi beer (AOB) but not max beer (MOB) were found to be proper between 3 and 5 minutes of peak time. All samples for peak value were at the level of over 60%. AOB showed the highest specific volume, and was the lowest in hardness (i.e. highest in softness) by TPA and storage days. In sensory evaluation, the difference test showed that AOB had the best volume, springiness, moistness, and softness. Moreover, in an overall preference test AOB scored the highest points in texture, flavor, taste, and overall acceptance.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.641-649
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• 2009

This study was conducted to investigate the effects of wheat germ on medium flour using falling number and RVA tests, as well as farinogram and rheofermentometer analyses. The wheat germ was added to the medium flour on a 3, 5, and 7% basis. Falling numbers increased with increasing amounts of wheat germ. Analysis of the RVA characteristics showed that the wheat germ additions did not have significant effects on the initial pasting temperature. In the farinogram, water absorption decreased with an increasing amount of wheat germ. Also, development time was longest in the control group and shortest in the group with the highest addition of wheat germ. The results of the effects of added wheat germ on fermentation by rheofermentometer analysis showed that the H'm value reached a maximum height at 3%. Finally, the volume of $CO_2$ lost was increased whereas the retention coefficient was decreased.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.37-45
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• 2014

Ball valves are used as a key element in the process industries. The industrial development of valves has increased steadily, but continued improvement requires high design reliability and long service life. Currently, the development of high performance valves is not easy because of the lack of relevant technology in Korea. Valves are being imported at a level of up to 58 percent of the domestic market, which represents a value of almost 7 million US dollars. Therefore, in this work, the improvement of the design and performance of industrial valves has been studied in an attempt to achieve valves that will have longer service life and better output during operation. The structural stability was evaluated using the ANSYS FSI (Fluid-Structural Interaction) module. Moreover, to obtain maximum product reliability, torque analysis simulation was performed to compare and experimental results. The simulation results were used to predict the change in torque by changes in shape, thereby reducing the time and cost of manufacturing a number of prototypes for experimental validation.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.697-705
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• 2010

This study was designed to investigate the effect of cranberry powder making pan bread. Cranberry powder at the level of 1 % (CP1), 3% (CP3), and 5% (CP5) was mixed with flour to make the breads. According to mixograph, the control, CP1 and CP3 except CP5 were found to bo proper between 3 and 5 min. in tenn of peak time (min). All samples for peak value were at the level of over 60% It meant that all samples were proper to make bread. By increasing the ratio of cranberry powder, pH, dough fermentation rate, volume and specific volume were decreased, and adhesiveness, springiness, cohesiveness and resilience except hardness were decreased in texture profile analysis. In crumbScan analysis, the addition of cranberry powder decreased the volume and increased crumb fineness of pan bread. In sensory evaluation, CP1 and CP3 showed good preference in aspect of flavor, taste, and overall acceptance.

• Food Science and Preservation
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• v.5 no.2
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• pp.167-171
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• 1998

Bulkogi(roast beef) seasoning stored without cap at 5$^{\circ}C$ and 23$^{\circ}C$ and within capped boule at 5$^{\circ}C$, 23$^{\circ}C$, 38$^{\circ}C$, 48$^{\circ}C$ and heat cycling(38$^{\circ}C$-1 week and 5$^{\circ}C$-1 week) and investigated sensory quality, pH, VBN, amino-N, surface color, and viable cell counts during 6 month storage. Nonpackaged Bulkogi seasoning was deteriorated by molds after 2 weeks at 23$^{\circ}C$ but did not showed any significant quality changes at 5$^{\circ}C$ for 1 month. Sensory scores of packaged sample rapidly declined with the temperature increase but chemical criteria was not significantly changed depending on temperature and storage time. Correlations between sensory scores and chemical parameters was not found, but sensory scores on color was correlated with lightness(L. value) of surface color(r=0.899). Heat cycle storage resulted in similar changes in quality to 38$^{\circ}C$ storage. Ql0 values calculated by sensory evaluation results as a quality index was 6, and the shelf-life of packaged Bulkogi seasoning was predicted 88 months at 23$^{\circ}C$.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.2
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• pp.43-50
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• 2012

According to the aging acceleration phenomenon of the population, Korean society is progressing toward the insecurity society on the 'blessing' or 'disaster'. The purpose of this paper is to establish direction of planning about the dwelling form of collective housing for the senior citizen who lives alone in rural and fishing villages. This focus of study is closely related to the health of the elderly and dwelling form preference. The results of research are as follows. First, the dwelling type of collective housing should be developed for elderly living alone, that must be secured by community life and private life at the same time. Second, it should be supported by such a level of application with Universal Design and Barrier Free Design. Third, collective housing served to the design that the elderly care, as one of the domiciliary care is value in having fact to psychological, physical intention. Fourth, it should be developed visit care or call care for welfare system service and community service manpower on the various types.

• Communications for Statistical Applications and Methods
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• v.3 no.2
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• pp.275-282
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• 1996

A life distribution F with survival function $\overline{F}$=1-F, finite mean $\mu$ and mean residual life m(t) is said to be NBUE(NWUE) if m(t)$\leq$($\geq$) .$\mu$ for t$\geq$0. This NBUE property can equivalently be characterized by the fact that $\varphi$(u)$\geq$($\leq$)u for 0$\leq$u$\leq$1, where $\varphi$(u) is the scaled total-time-on test transform of F. A generalization of the NBUE properties is that there is a value of p such that $\varphi$(u)\geq.u$ for 0$\leq$u$\leq$p and $\varphi$(u)\leq$$\leq$u$\leq$1, or vice versa. This means that we have a trend change in the NBUE property. In this paper we point out an error of Klefsjo's paper (1988). He erroneously takes advantage of trend change point of failure rate to calculate the empirical test size and power in lognormal distribution. We solves the trend change point of mean residual lifetime and recalculate the empirical test size and power of Klefsjo (1988) in mocensoring case.

• Mycobiology
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• v.46 no.4
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• pp.440-447
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• 2018

Dual biocontrol of both insects and plant pathogens has been reported for certain fungal entomopathogens, including Beauveria bassiana and Lecanicillum spp. In this study, we demonstrate, for the first time, the dual biocontrol potential of two fungal isolates identified by morphological and phylogenetic analyses as Isaria javanica. Both these isolates caused mortality in the greater wax moth, and hence can be considered entomopathogens. Spores of the isolates were also pathogenic to nymphs of the green peach aphid (Myzus persicae), with an $LC_{50}$ value of $10^7spores/mL$ 4 days after inoculation and an $LT_{50}$ of 4.2 days with a dose of $10^8spores/mL$. In vitro antifungal assays also demonstrated a strong inhibitory effect on the growth of two fungi that are pathogenic to peppers, Colletotrichum gloeosporioides and Phytophthora capsici. These results indicate that I. javanica isolates could be used as novel biocontrol agents for the simultaneous control of aphids and fungal diseases, such as anthracnose and Phytophthora blight, in an integrated pest management framework for red pepper.

• Human Ecology Research
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• v.57 no.2
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• pp.271-280
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• 2019

This study collects and analyzes data on educational philosophy and method for domestic and overseas alternative schools. This information is then applied to educational purpose and curriculum for a home economics curriculum that develops unique characteristics for Korean alternative education.This study collected and analyzed the characteristics of educational content and educational elements from two renowned alternative schools: Waldorf School in Germany and Summer Hill in the United Kingdom. The research results were as follows. First, it is necessary to create new word instead of using the term 'alternative education'. Second, among characteristics of Korean home economics curriculum, 'practical problem-solving ability', 'independent living ability', and 'relation forming ability' should be utilized to create a school with an independent curriculum and to establish a unique brand value. Third, time investment on instructor education should be made to cultivate competent and charming instructors as the center of a school. Lastly, school education should manage student's life at school and after graduation. The school and instructor should provide alternative education while thinking they are responsible for 50 years of a student's future life. This study helps show that alternative education is not perceived as a superficial and generalized education and that Korean alternative education can find similar characteristic to those of overseas cases.