• Composites Research
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• v.13 no.2
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• pp.81-90
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• 2000

For automotive applications, a sandwich sheet which was made of a 5182 aluminum alloy (AA5182) sheet and a polypropylene (PP) sheet, AA5182/PP/AA5182, has been developed. In order to evaluate its formability, the forming limit diagrams (FLD) of the 5182 aluminum alloy sheet with 0.2mm thickness and the sandwich sheet with 1.2mm thickness have been obtained based on the modified Marciniak-Kuczynski (M-K) theory. To account for the anisotropy of the sheet, Hill's 1948 yield function has been applied. The FLD of the sandwich sheet was predicted to be better than that of the AA5182 sheet, which was well confirmed by experiments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.731-738
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• 2006

Facing congestion, people want to know traffic information about their routes, especially real-time link travel time (LTT). In this paper, as a sequel paper of the previous non-taxi based LTT generating study by Choi et al. (1998), taxi based GPS probes have been tried to produce LTT for urban arterials. Taxis in itself are good deployment mode of GPS probes although it by nature experiences boarding and alighting time noises which should be accounted. A heuristic real-time dynamic outlier filter algorithm for taxi GPS probe has been developed focusing on urban arterials. An actual traffic survey for dynamic link travel times has been conducted using license plate method for the test arterials of Seoul city transportation network. With the algorithm, it is estimated that 70% of outliers have been filtered and the relative error has been improved by 73.7%. The filtering algorithm developed here would be expected to be in use for other spatial sites with some calibration efforts. Some limitations and future research agenda have also been discussed.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.193-197
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• 2014

Transgenic crops that produce insecticidal toxins have a great potential for controlling target pest insects, but there is a growing concern about unintended influences on non-target species. In the present study, the preferences and performance of non-target green peach aphid, Myzus persicae (Sulzer), on transgenic cabbages (Brassica oleracea) that produce Bt toxin (Cry1Ac1) and untransformed control plants were investigated as a part of risk assessment. In a free-choice situation, the number of nymphs larviposited by 10 winged adults over 3 days was $21.9{\pm}1.8$ and $22.5{\pm}2.2$ on transgenic and the control plants, respectively, indicating that the aphids did not discriminate between the two types of plants. In a performance assay, the development time (D) and intrinsic rate of increase (rm) of wingless aphids reared on transgenic and control plants were also similar (D, $5.8{\pm}0.2$ and $5.9{\pm}0.1$ (days) and rm, $0.7{\pm}0.1$ and $0.8{\pm}0.1$, for transgenic and control plants, respectively). These results suggest that M. persicae is not significantly affected by transgenic Bt cabbage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.931-938
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• 2014

This study presents a systematic method of evaluation with the premise that satisfaction rating scale of the walking environment will vary according to the characteristics of land use by footpath types. Ultimately, it aims to contribute to the effective management and improvement of footpaths. The result of the study shows a statistically significant difference in the indicators and it's weights for walking environment on new town, old town, commercial areas, subway station, river and park by footpath types. After applying the walking environment assessment model to some of the footpaths in Suwon, it was found that actual level can be simulated successfully in reality. Therefore, the result of the study is expected to help determining the priorities for the walking environment improvement for the local government.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.153-163
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• 2020

This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (r_m) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.428-436
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• 2013

To obtain biological basic data for the conservation strategies establishment of a rare mistletoe species, Loranthus tanakae(Loranthaceae) in Korea, the distribution range, habitat characteristics and an assessment of the conservation status on the natural populations of L. tanakae were investigated. As a result, the natural populations of L. tanakae were distributed in Bakdudaegan from Mt. Chiri to Mt Seorak in Korea penninsula, and 97.8% of surveyed individuals of the mistletoe species were found in Gangwon province. In natural populations, 1,385 individuals of L. tanakae were parasitic on 480 host trees, and distributed in sunshiny ridges of mountains of altitude range of 353 m to 1,250 m. The range of host trees of L. tanakae were composed of 5 families, 6 genera, 9 species, 1 subspecies, and of these, Quercus mongolica was preferred with 81.5% (389 trees among 480 host trees). As a result of assessing the conservation status through IUCN, L. tanakae was evaluated as Vulnerable (VU). It was considered that Mt. Seorak, Mt. Taegi and Mt. Odae population as habitats with the highest density of distribution of natural populations of L. tanakae should be designated as the protected areas. Thus, conservation strategies and related methods of the natural populations of L. tanakae were also discussed for the sustainable conservation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.414-417
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• 2008

A lid & frame used as the shield of electromagnetic waves in cellular phones are composed of frame, which is welded at their electric circuits, and lid, of which debonding and joining are available from the frame. Typical lid & frame were mechanically bonded by contact between the embossing of lid and the piercing of frame Bonding force of this part have to allow us to detach the lid from frame for exchange or fix of the electric part and have to be high enough to protect the electric part from external impacts. This study is designed to estimate the effect of design variable of lid & frame on its debonding force. Estimations were performed by finite element method.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.652-655
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• 2004

In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if tills costs a lot. It was not arrange the standard for performance evaluation test method and quality maintenance for materials, even it has been used various injection repairing agent. In conclusion, We suggest that the test method for repair materials for leakage to establish the leakage repairing technology as increase of structure demand, so that the necessity of the establishment of the quality control standard and the performance testing way on the relevant water-proof seal is increasing a lot to regulate the water-proof technology and the leakage repair technology.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.956-957
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• 1995

대부분의 AS/RS 운영정책 연구는 등급별 저장이 임의저장보다 우수한 수행도를 나타낸다고 결론짓고 있다. 그러나 실제 현장에서는 임의 저장이나 이와 유사한 형태의 근거리 저장이 주로 사용되고 있는 실정이다. 이와 같이 AS/RS 운영에 관련된 연구결과들이 현실에서 적용되지 못하고 있는 데는 여러 가지 이유가 있겠지만 본 연구에서는 빈번하게 바뀌고 있는 생산계획에 그 원인을 두었다. 신제품의 투입으로 기존 제품의 생산량에 변화가 일어나는 경우가 빈번한 생산현장을 감안하여 GPSS로 AS/RS의 모형을 구축하고 그 운용상태를 파악해 볼 수 있도록 임의저장, 2등급저장, 3등급저장 등의 경우를 시험.분석하였다. 각 경우별로 적정 허용 변동율과 최대 허용 변동율, 변동에 대한 반응도 등이 분석되었다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.11
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• pp.1267-1273
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• 2009

Hot press forming can produce high-strength components by rapidly cooling between closed punch and die after hot forming using quenchable boron steel austenized in a furnace. In the hot press forming process, the cooling rate is influenced by the size, position and arrangement of the cooling channel and the file condition of cooling water in the die. Also, mechanical properties of the final components and operation time are related to cooling rate. Therefore, the design of optimized cooling channel is one of the most important works. In this paper, the effect of position and size of the cooling channel on the cooling rate was investigated by using design of experiment and FE analysis in hot press bending process. Therefore the optimum cooling channel ratio was presented in the HPB.