• Journal of Sericultural and Entomological Science
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• no.12
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• pp.21-36
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• 1970

This studies have been carried out to 3nd various causes of cleanness defects on raw silk which has been increased since 1967 in Korea, so that this treatise may be a guide inform action to improve such a defect in future. The cocoon treatment for the proposed work was carried starting with in worst condition to find the critical limit of degrading through such a work. And various analysis have been also worked out using the annual silk testing data past a few years. The results obtained are as follows. 1. There was a great relationship between cleanness and neatness result. 2. Cleanness result is greatly influenced by mounting conditions and handling of cocoons, which brought 40 percent lower as cleanness result than standard ones in which caused minor defects, especially loops and split ends, so the bad mounting conditions and handling of fresh cocoons degraded raw silk from 4A grade to E. 3. The use of good water quality brought the difference of 1.04 percent in cleanness result rather than the use of bad one. 4. Well technical work brought the difference of 0.86 percent in cleanness result rather than poor technical work. 5, Satisfactory cocoon drying installation brought the difference of 1.97 percent in cleanness result rather than insufficient one. 6. Automatic reeling machine marked lower 1,55 percent in cleanness result than multi-end reeling machine. 7. The degrading of cleanness result from 1965 year silk to 1969 year silk marked 1.99 percent, which almost responds to the degrading rate from good to poor cocoon drying installed cleanness results. In view of this result, nowadays, insufficient cocoon drying installation may be main factor to be worse cleanness result of Korean raw silk. 8. The factors of cleanness defect in raw silk once supplied with cocoon into factory are water quality, technique evaluation, cocoon drying capacity and s： reeling machine. The relationship between cleanness result and above factors are as follows. cleanness result＝neatness result＋1.6－1.04(1－a)－1.97(1－b)－0.86(1-c)＋1.55${\times}$d a： The successive we ratio of water quality (0\longrightarrowl) b： The successive ratio of satisfactory cocoon drying installation (0\longrightarrowl) c： The successive ratio of well technical work (0\longrightarrowl) d： 1 in case multi-end reeling machine o in case automatic reeling machine 9, It is not admitted that there is heavy relationship between cleanness occurrence and nonbreaking reel ability. That mal$.$ be sowed with silk reeling technique. 10. The bad mounting conditions caused the worse result on the cocoon quality as much as cleanness. 11. Besides mounting conditions, there may be another factors affecting on the low reel ability of cocoons in Korea.

• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.121-138
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• 2011

More affordable and available cutting-edge technologies (e.g., wireless vehicle communication) are regarded as a possible alternative to the fixed infrastructure-based traffic information system requiring the expensive infrastructure investments and mostly implemented in the uninterrupted freeway network with limited spatial system expansion. This paper develops an advanced decentralized traveler information System (ATIS) using vehicle-to-vehicle (V2V) communication system whose performance (drivers' travel time savings) are enhanced by three complementary functions (autonomous automatic incident detection algorithm, reliable sample size function, and driver behavior model) and evaluates it in the typical $6{\times}6$ urban grid network with non-recurrent traffic state (traffic incident) with the varying key parameters (traffic flow, communication radio range, and penetration ratio), employing the off-the-shelf microscopic simulation model (VISSIM) under the ideal vehicle communication environment. Simulation outputs indicate that as the three key parameters are increased more participating vehicles are involved for traffic data propagation in the less communication groups at the faster data dissemination speed. Also, participating vehicles saved their travel time by dynamically updating the up-to-date traffic states and searching for the new route. Focusing on the travel time difference of (instant) re-routing vehicles, lower traffic flow cases saved more time than higher traffic flow ones. This is because a relatively small number of vehicles in 300vph case re-route during the most system-efficient time period (the early time of the traffic incident) but more vehicles in 514vph case re-route during less system-efficient time period, even after the incident is resolved. Also, normally re-routings on the network-entering links saved more travel time than any other places inside the network except the case where the direct effect of traffic incident triggers vehicle re-routings during the effective incident time period and the location and direction of the incident link determines the spatial distribution of re-routing vehicles.

• Toxicological Research
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• v.33 no.2
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• pp.107-118
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• 2017

Although alternative test methods based on the 3Rs (Replacement, Reduction, Refinement) are being developed to replace animal testing in reproductive and developmental toxicology, they are still in an early stage. Consequently, we aimed to develop alternative test methods in male animals using mouse spermatogonial stem cells (mSSCs). Here, we modified the OECD TG 489 and optimized the in vitro comet assay in our previous study. This study aimed to verify the validity of in vitro tests involving mSSCs by comparing their results with those of in vivo tests using C57BL/6 mice by gavage. We selected hydroxyurea (HU), which is known to chemically induce male reproductive toxicity. The 50% inhibitory concentration ($IC_{50}$) value of HU was 0.9 mM, as determined by the MTT assay. In the in vitro comet assay, % tail DNA and Olive tail moment (OTM) after HU administration increased significantly, compared to the control. Annexin V, PI staining and TUNEL assays showed that HU caused apoptosis in mSSCs. In order to compare in vitro tests with in vivo tests, the same substances were administered to male C57BL/6 mice. Reproductive toxicity was observed at 25, 50, 100, and 200 mg/kg/day as measured by clinical measures of reduction in sperm motility and testicular weight. The comet assay, DCFH-DA assay, H&E staining, and TUNEL assay were also performed. The results of the test with C57BL/6 mice were similar to those with mSSCs for HU treatment. Finally, linear regression analysis showed a strong positive correlation between results of in vitro tests and those of in vivo. In conclusion, the present study is the first to demonstrate the effect of HU-induced DNA damage, ROS formation, and apoptosis in mSSCs. Further, the results of the current study suggest that mSSCs could be a useful model to predict male reproductive toxicity.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.52-60
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• 2006

This study investigated how wood properties (i.e., annual rings, sapwood, heartwood, and cracks) might affect preservative treatment in Japanese larch (Larix leptolepis) round-wood product. We specially focused on small-diameter (~10 cm diameter) wood that is commercially sold in market. Among 100 wood samples, the groups of sample with 13~16, 17~20 annual rings represented 33 and 27 in each frequency, while 2~3 and 4~5 mm annual ring width accounted for 72 and 68 in frequency. More than a half (54%) of wood samples contained a mix of heartwood and sapwood in its surface. The rest (46%) had only heartwood exposed in the wood surface. A wide range of checks were showed in the wood samples, but the highest frequency was observed in samples with 1~6 surface (1~14 mm in size) checks and 1~4 end-grain (8~14 mm in size) checks in each round-wood sample. Pressure treatment resulted in a wide range of penetration of ACQ (Alkaline Copper Quat) into the wood, showing $4.3{\pm}4.19mm$ penetration in the wood samples contained a mix of heartwood and sapwood in its surface. However preservative treatment was much less effective for the heartwood only wood samples, ranging average 1.3 mm with ACQ and 1.1 mm with CCA (Chromated Copper Arsenate). These penetration results shown in heartwood samples did not meet the penetration standard that is required for H3 by the Korean Forest Service in relation to wood preservation treatment. These low penetration results were not significantly improved even if we incised wood samples to improve treatment effect, showing only small increase of 0.7 mm with ACQ and 0.6 mm with CCA. When preservative treatment was tested with heartwood, penetration of preservatives decrease with increase of annual rings per a cross-section area (r=0.5345). We also found that the length and number of check had no effect on preservative treatment, showing r=0.1301 and r=0.1802, respectively.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.262-266
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• 2016

We investigated the characteristic demographics for visitors to Mujechi bog on Mt. Jungjok, with the purpose of developing a management strategy for the conservation and wise use of the montane wetland. Using daily visitor data from 2007, 2011, and 2015 we extracted and analyzed; visitation date, age, residential areas, purpose of visitation and the time allotted for the visit. The largest age cohort was the decade of the fifties(36.8%/total number of visitors) and followed by the decade of the forties(30.4%). The majority of visitors were from Ulsan(67%), Busan(16.6%), and Yangsan(10.8%). The visitors' primary objectives were to hike Mt. Jungjok(39-64.4%) or view Mujechi bog(18.7-51.8%) during the weekend. People visited more during the weekend than weekdays(F=6.19, p<0.002). In addition, there was a clear seasonality obvious in the monthly visits. The proportion of visitors were present in spring and fall, the month with the highest visitation rate was May at $15.6{\pm}2.8%$($mean{\pm}S.D.$). This increase in May was partly due to the desire to see the Korean azalea in bloom in the spring. Montane bog, like Mujechi, could be highly affected by disturbance(e.g. stamping, sediment inflow) caused by visitors. Therefore, it is suggested, based on the level of visitation that to reduce possible human disturbance effects, that either a seasonal restriction or a yearly alternation of trails be established. Visitors to the wetland should be restricted access to certain areas of the wetland, or be required to go in the accompaniment of a ranger or warden.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.71-84
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• 2004

There is a growing demand for agrometeorological information that end-users can use and not just interesting information. lo achieve this, each region/community needs to develop and provide localized climate and weather information for growers. Additionally, provide tools to help local users interpret climate forecasts issued by the National Weather Service in the country. Real time information should be provided for farmers, including some basic data. An ideal agrometeorological information system includes several components: an efficient data measuring and collection system; a modern telecommunication system; a standard data management processing and analysis system; and an advanced technological information dissemination system. While it is conventional wisdom that, Internet is and will play a major role in the delivery and dissemination of agrometeorological information, there are large gaps between the "information rich" and the "information poor" countries. Rural communities represent the "last mile of connectivity". For some time to come, TV broadcast, radio, phone, newspaper and fax will be used in many countries for communication. The differences in achieving this among countries arise from the human and financial resources available to implement this information and the methods of information dissemination. These differences must be considered in designing any information dissemination system. Experience shows that easy across to information more tailored to user needs would substantially increase use of climate information. Opportunities remain unexplored for applications of geographical information systems and remote sensing in agro meteorology.e sensing in agro meteorology.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.161-167
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• 2007

In this study, we constructed and tested retrovirus vectors designed to express the human thrombopoietin gene under the control of the tetracycline-inducible promoters. To increase the hTPO gene expression at him-on state, WPRE sequence was also introduced into retrovirus vector at downstream region of either the hTPO gene or the sequence encoding reverse tetracycline-controlled transactivator (rtTA). Primary culture cells (PFF, porcine fetal fibroblast; CEF, chicken embryonic fibroblast) infected with the recombinant retrovirus were cultured in the medium supplemented with or without doxycycline for 48hr, and induction efficiency was measured by comparing the hTPO gene expression level using RT-PCR, western blot and ELISA. Higher hPTO expression and tighter expression control were observed from the vector in which the WPRE sequence was placed at downstream of the hTPO (in CEF) or rtTA(in PFF) gene. This resulting tetracycline inducible vector system may be helpful in solving serious physiological disturbance problems which have been a major obstacle in successful production of transgenic animals.

• Economic and Environmental Geology
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• v.17 no.3
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• pp.179-195
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• 1984

The Jurassic Daejeon and Nonsan granitoids are "S-type" syntectonic calc-alkaline two-mica monzogranite and granodiorite, respectively. With evidences of high CaO, $Al_2O_3$, LIL/HFS elements, total REE, (Ce/Yb)N and initial ($^{87}Sr/^{88}Sr$) ratio, and no significant Eu anomaly, the primary magmas for the Daejeon and Nonsan granitic rocks are derived from partial melting of the Precambrian granulite (e.g. grey gneisses). But those Jurassic granitoids crystallised from different chemical characteristics of parental magmas which is mainly due to varying degree of partial melting of the granulite (crustal anatexis). The absence of significant anomalous Eu($Eu/Eu^*=O.82{\sim}1.00$) in the Daejeon and Nonsan granitoids could indicate that feldspars, mainly plagioclase, did not separate from the magmas. The parental hydrous magmas could not rise appreciably above their source region before crystallisation. The Jurassic granitoids may be resulted by closing-collision situation and belong to the Hercynotype (Pitcher 1979) such as compressive ductile regime of an intracontinental orogen.

• Korean Journal of Environmental Agriculture
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• v.5 no.1
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• pp.35-42
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• 1986

This study was carried out to investigate the distribution of arsenic (As) fractions in paddy soils in relation to some soil characteristics and to find out the relationship between As fractions in soil and As content in brown rice. Soils and rice samples were collected from paddy field adjacent to arsenic mining and refinery sites. Sequential extraction procedures were used to fractionate As in soils into the designated forms of water soluble-As, Al-As, Fe-As, Ca-As, and residual-As. The results obtained were as follows: 1. The percent distribution of As fractions in soil showed a wide difference depending on some soil properties. The relative abundance of the extractable inorganic As fractions was in the order of Fe-As>Al-As>Ca-As>Water soluble-As regardless of mining and refinery sites. Residual-As fraction was more abundant in mining site than in refinery site. 2. With increasing soil pH, the percent distribution of Fe-As and Al-As fractions were decreased, but that of Ca-As and Residual-As fractions increased. The percent distribution of Al-As fraction in soil was negatively correlated with soil CEC, but others showed positive relationships. 3. Active Al and Fe content, and exchangeable Ca content in soil were positively correlated with the percent distribution of Al-As, Fe-As, and Ca-As fractions in soil respectively, and higher correlation between them was shown in mining site than in refinery site. 4. Soil As fractions, except for water soluble-As, showed significant correlation with among each others and also with 1N HCl extration method using as the common soil As extractant in Korea. 5. Arsenic content in brown rice had highly significant correlation with Al-As fraction in soil and it also showed significant correlation with Fe-As and Ca-As fractions, Total-As, and 1N-HCl extractable As.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.77-82
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• 1998

As a fundermental research for quality stailization of herb extract, the effects of water activity on microbial growth in herb extract were investigated. Herbs-Panax ginseng, Cinnamomum cassia, Lycium chinense, Zyzyphus jujuba, Lindera obtusilobum-were mixed and extracted with water at $80^{\circ}C$ and concentrated at $75^{\circ}C$. Water activity of the herb extract was adjusted to 0.86, 0.80 and 0.69, using water activity analyzer. The extracts were incubated for 180 days at $40^{\circ}C$ and then examined microbial cell counts and some physicochemical properties. In the extract of $a_{w}$ 0.86, 18 CFU/g of initial viable cell was increased to 80 CFU/g with 90 days of incubation and to 190 CFU/g 180 days of incubation. In the extract of $a_{w}$ 0.80, 24 CFU/g of initial viable cell was also increased to 83 CFU/g during the 90 days of incubation and to 170 CFU/ g for the 180 days of incubation. However, in the extract of $a_{w}$ 0.69, viable cell after 180 days of incubation was remained at almost the same level as initial viable cell. pH of herb extract was reduced in proportion to the decrease in water activity. The TLC (thin layer chromatography) patterns of ginseng saponins of herb extract did not show any significant changes after 180 days of incubation. Growth of pathogenic microorganisms was inhibited more with lower water activity of the herb extracts. In the herb extract inoculated with Candida albicans and Aspergillus niger, initial viable cells of 150 and 140 CFU/g were decreased to 30 and 20 CFU/g, repectively, after 30 days of incubation at $28^{\circ}C$. In the case of herb extract inoculated with Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, growth of the bacteria was totally inhibited even after 30 days of incubation at $37^{\circ}C$.