• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.896-905
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• 2012

Recently, the application of the plastic material to automotive components and structures has steadily increased to satisfy demands on the saving of overall weight and the improvement of energy efficiency. The objective of this paper is to investigate the development of a bumper back-beam using a thermoplastic olefin (TPO). The bumper back-beam was designed to be manufactured from the injection molding process. In order to obtain a proper design of the bumper back-beam, three-dimensional finite element analyses were performed for various design alternatives. Stress-strain curves for different strain rates were measured by high speed tensile tests of the TPO to consider strain rate effects in the FEA. The influence of the sectional shape and the rib formation on the contact force-intrusion curves, the deflection and the energy absorption rate of the bumper back-beam was examined. From the results of the examination, a proper design of the bumper back-beam was acquired. The bumper back-beam consisting of TPO was fabricated from the injection moulding process and the vibration welding. Pendulum crash tests were carried out using the fabricated bumper back-beam. The results of the tests showed that the designed bumper back-beam can satisfy requirements of the federal motor vehicle safety standard (FMVSS). Through the comparison of the previously designed bumper back-beam with the newly designed bumper back beam, it was noted that the weight of the designed bumper back-beam is lighter than that of the previously designed bumper back beam by nearly 16 %. In addition, it was considered that the newly designed bumper back beam can improve recycling of the bumper back-beam.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1163-1168
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• 2004

In order to establish the experimental clinical model for evaluating the influences on the sexual hormones of SD-rat administrated with Methoxychlor(MET), it was dissolved in acetone and olive oil (1:19), which was administrated orally at doses of 200㎎/㎏ body weight/day for 7 days. The Testosterone value was measured in sera by Gamma Count with 1251 isotype, also weights of the body, testis and liver were measured for 15 weeks. Testosterone in the serum of intacted SD-rats was 0.51±0.43ng/㎖(n=5), but it was 0.69±0.18(n=2)ng/㎖l on 1 week. 0.28±0.05ng/㎖(n=2) on 3 week, 1.52±0.95ng/㎖(n=3) on 5 week, and 0.54±1.95 ng/㎖(n=3) 15 week post-dosing MET, respectively. Histologically, the numbers of spermatozoa and Leydig cells were reduced, which might influence to reduce sexual hormone, and AST and ALT was not increased in the serum due to administrating with MET, blood profile was not changed according to the administration of MET excepting MCH(Mean Corpuscular Hemoglobin). This study suggest that change of male sexual hormone by MET be a experimental model for evaluating some drugs associate with sex hormone.

• Journal of Korean Society of Rural Planning
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• v.21 no.2
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• pp.189-199
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• 2015

This study made use of 9 types of utilizing idle farmland deducted from existing research in order to examine cases by type of idle farmland, and selected representative cases by type after analyzing contents of 165 available newspaper articles. Selected Cases were assorted into agricultural use and nonagricultural use, and agricultural use are as followed. (1)Community Service/Farming type is the case of Gimhae city reported on 'Busan Ilbo', (2)High Income/Farming type is the case of cooperative unit of Geumjeong crude drug in Yeongam appeared in 'Newsis', and the case of Omija industry in Mungyeong reported on 'Hankyoreh', (3)Tourism/Landscape/Farming type is the case of rape flowers and buckwheat flowers in Gupo village reported on 'Asia News Agency', (4)Stock Raising/Farming type is the case of growing foraging crops published in 'The Daejeon Ilbo', (5)Weekend farm type is the case of utilizing idle farmlands and creating weekend farm reported on 'Mediawatch', (6)High income/Forest type is creating Mulberry cultivation areas in Hamyang-Gun published in 'Yonhap News', (7)Ecology/Landscape/Forest type is forestation project of idle land reported on 'Newsis', (8)Agricultural Experience Study type is the case of managing agricultural experience study center in Dosun elementary center published in 'Sisajeju' and the case of non-agricultural application case, (9)Ecological Environment type is the case of wetland restoration of idle farmland in Gochang. This study investigated and arranged detailed contents by the literature search and interview investigation according to investigating items such as utilizing area, main agent, purpose, utilizing item, utilizing content, etc. by case. With that, it deducted implications as well as case characteristics, and finally suggested political proposals through the case analysis.

• KOMUNHWA
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• no.56
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• pp.29-58
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• 2000

A lot of dolmens without burial chamber have been brought to the light around Honam (southwestern provinces of Korea) area. Even though they are commonly classified as dolmens of surrounding stone type(圍石式), it seems necessary to put under the category of

• Research in Plant Disease
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• v.12 no.1
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• pp.62-64
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• 2006

July in 2005, we collected infected maize plant that showing stripe dwarf disease on maize leaf in Jeonbuk provinces including Gochang-gun and conducted genomic dsRNA extraction and RT-PCR. Genomic dsRNA was extracted directly in infected maize plant and electrophoresis in agarose gel. We confirmed 10 segments of genomic dsRNA. We conducted RT-PCR by genomic dsRNA and specific primer of S7, S8 and S10. As a result, specific band of expected size was confirmed respectively. In the results of dsRNA and RT-PCR analysis, we confirmed Rice black-streaked dwarf fijivirus (RBSDV) from naturally infected maize plant. Occurrence of RBSDV of maize plant was dealt 22 ha's damage in maize field. The occurrence rate was 80% in a lot of places of disease.

• Research in Plant Disease
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• v.14 no.3
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• pp.223-225
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• 2008

This study was carried out to identify the Rice black-streaked dwarf virus that infected maize plants collected from Gochang-gun in Jeollabukdo in 2005. The genomic dsRNA from infected plants was extracted and the genome pattern was analyzed by polyacrylamide gel electrophoresis. Results of the electrophoresis revealed the already known to-segment genome and the difference of mobility was confirmed in isolates by collected areas. The RBSDV was identified from the result of RT-PCR using the template of extracted dsRNA and specific primer. The results of S10 cloned to pGEM-T vector and the conducted in sequence analysis consisted of 1,801nt and 559aa. This was of the same size as the RBSDV S10 identified in rice, and the change was confirmed in 18 base and displayed homology of 99%.

• Journal of Ginseng Research
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• v.40 no.1
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• pp.90-96
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• 2016

Background: Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Methods: Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Results: Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between $8^{\circ}C$ and $27^{\circ}C$, occurred slightly less frequently in hours during night times under the shade (91%) than outside (92%). Humidity conditions favorable for development of a foliar disease, e.g., relative humidity > 70%, occurred slightly more frequently under the shade (84%) than outside (82%). Effectiveness of correction schemes to an empirical LWD model differed by rainfall conditions for the estimation of LWD under the shade using weather measurements outside the shade as inputs to the model. During dew eligible days, a correction scheme to an empirical LWD model was slightly effective (10%) in reducing estimation errors under the shade. However, another correction approach during rainfall eligible days reduced errors of LWD estimation by 17%. Conclusion: Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.556-563
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• 2015

Chinese cabbage is one of the most important vegetables in Korea and a target crop for market stabilization as well. Remote sensing has long been used as a tool to extract plant growth, cultivated area and yield information for many crops, but little research has been conducted on Chinese cabbage. This study refers to the derivation of simple Chinese cabbage growth prediction equation by using RapidEye derived vegetation index. Daesan-myeon area in Gochang-gun, Jeollabuk-do, Korea is one of main producing district of Chinese cabbage. RapidEye multi-spectral imagery was taken on the Daesan-myeon five times from early September to late October during the Chinese cabbage growing season. Meanwhile, field reflectance spectra and five plant growth parameters, including plant height (P.H.), plant diameter (P.D.), leaf height (L.H.), leaf length (L.L.) and leaf number (L.N.), were measured for about 20 plants (ten plants per plot) for each ground survey. The normalized difference vegetation index (NDVI) for each of the 20 plants was measured using an active plant growth sensor (Crop $Circle^{TM}$) at the same time. The results of correlation analysis between the vegetation indices and Chinese cabbage growth data showed that NDVI was the most suited for monitoring the L.H. (r=0.958~0.978), L.L. (r=0.950~0.971), P.H. (r=0.887~0.982), P.D. (r=0.855~0.932) and L.N. (r=0.718~0.968). Retrieval equations were developed for estimating Chinese cabbage growth parameters using NDVI. These results obtained using the NDVI is effective provided a basis for establishing retrieval algorithm for the biophysical properties of Chinese cabbage. These results will also be useful in determining the RapidEye multi-spectral imagery necessary to estimate parameters of Chinese cabbage.

• Journal of Korean Society of Rural Planning
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• v.27 no.4
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• pp.43-54
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• 2021

This study analysed changes in rural tourism between before and after COVID-19 using LDA topic analysis. In order to understand the changes in rural tourism, blog data including the keyword 'Gochang-gun travel' was used. As a result of LDA topic analysis with blog data retrieved, the study found nine topics in 2019 and 2020. 2019 and 2020 are, generally, consistent in topics, but the three topics related to rural experiential tourism that appeared in 2019 did not appear in 2020. In 2020, three new topics emerged: Beach vacations and campings. New travel activities of noncontact with other people(Untact tourism in Korean context) in the COVID-19 era, and The negative impacts on travel businesses and behaviours from COVID-19. Especially, the adverse effects of COVID-19 have made an enormous decline in rural experience tourism destinations and cancellation of local festivals. On the other hand, new tourism activities have emerged due to COVID-19. Those activities have included camping, drive-thru destinations, and cycling. Ecological and natural tourist sites such as Ungok Wetland, Seonunsan Mountain, Seonunsa Temple, and Gusipo Beach appeared. These tourist destinations have a quiet atmosphere and less density place noncontacting with other people when visiting. Also, because overseas travel has become difficult, long-term stay travel in rural areas has appeared. This study indicates that COVID-19 has less impacted rural tourism than other tourism destinations with these positive and negative impacts.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.4
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• pp.23-33
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• 2011

In this study, the data that examined the chloride ion concentration of ground water wells in the west coast of Jeollabukdo applying the GIS spatial estimation method were analyzed. In particular, through the designation of a validation point among ground water wells and then the analysis of error characteristics of the chloride ion concentration by each method of IDW (Inverse Distance Weight), Spline, and Kriging Interpolation method which is proper for estimating salt water intrusion was selected. The main conclusion from this study is as follows. First, as a result of analyzing the error characteristics of various spatial estimation methods by using the data from the chloride ion concentration of 485 ground water wells, the IDW method was found to be the most appropriate for estimating chloride ion concentration by salt water intrusion. Second, analyzing the average chloride ion concentration of the targeted regions has revealed that Gunsan-si with the record of $541mg/{\ell}$ did not meet water quality standards even for industrial use. Both Gimje-si and Gochang-gun satisfied drinking water quality standards and Buan-gun with $272mg/{\ell}$ was slightly below the standards for drinking water. Third, concerning the results of analysis according to administrative districts, as the areas adjacent to the west coast such as Daemyeong-dong, Joong-dong, Jangjae-dong and Guemam-dong in Gunsan-si are found to have very high chloride ion concentration, and both Hoehyeon-myeon and Daeya-myeon bounded by the Mankeong river did not meet water quality standards even for industrial use. From these facts, it is concluded that salt water intrusion has a great effect on Gunsan-si generally.