• Korean journal of applied entomology
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• v.46 no.3
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• pp.349-356
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• 2007

Three active components (Z8-12:Ac, E8-12:Ac, and Z8-12:OH) are known in sex pheromone of the oriental fruit moth, Grapholita molesta, and have been commercially available to apply for population monitoring and mating disruption. However, there have been variation among commercial products in pheromone composition and amount impregnated in each pheromone releaser. This study was performed to optimize factors influencing on pheromone monitoring of G. molesta by analyzing pheromone composition/amount, effective period of releaser, and trap type/placement in apple trees. High purity of Z8-12:Ac component was effective to attract males, in which 96% or more of cis acetate isomer component appeared to be optimal composition. Pheromone amounts ($0.01-1\;{\mu}g$) impregnated in each rubber dispenser did not give significant effect on monitoring during 90 days from June to August. "Delta" trap was much more efficient than "cone" trap to collect males. Trap installation was another factor, in which placing traps at canopy level was much efficient than at trunk or ground levels. Pheromone trap monitoring with these optimal factors indicated three to four adult peaks from June to September in addition to high overwintering population from April to May in pesticide-applied orchards in Andong, Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.1
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• pp.61-68
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• 2000

Gas-phase hydrogen peroxide(H2O2) concentrations were measured to investigate it's distribution in the ambient air in downtown Seoul(Kwanghwamum and Mullae-dong). These measurements were made during four season, from April 30, 1998 to January 29, 1999, using Cold Trap and HPLC. Measurements were also made of other photochemical oxidants and trace gases(O3, NO2, CO and SO2) and meteorological parameters(relative humidity, temperature, solar radiation and wind speed). The mean of all observations was 0.10 ppbv and the range measured was below the level of detection(>0.01 ppbv) to 0.47ppbv. The higher seasonal mean concentrations showed during the summer(0.21 ppbv) and concentrations of H2O2 showed a diurnal variation with maximum concentrations in the afternoon(12:30∼14:00). The results from the corrrelation analysis showed that the concentration of gaseous H2O2 is strongly dependent on the other air pollutants(NO2, CO and O3) and meteorological parameters(relative humidity, temperature and solar radiation.)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.58-62
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• 1995

Thermally stimulated currents have been measured to investigate the trap characteristics of the MONOS structures with the tunneling oxide layer of 27${\AA}$ thick nitride layer of 73${\AA}$ thick and blocking oxide layer of 40${\AA}$ thick. By changing the write-in voltage and the write-in temperature, peaks of the I-T characteristic curve due to the nitride bulk traps and the blocking oxide-nitride interface traps ware separated from each other experimentally. The results indicate that the nitride bulk traps are distributed spatially at a single energy level and the blocking oxide-nitride interface traps are distributed energetically at interface.

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.75-82
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• 2015

To overcome the stream fragmentation and blockage of migration of fishes by dams and weirs, fishways are commonly installed. However, limited studies were conducted for effectiveness and suitability of fishways installed in Korean streams. In this study, we investigated fish usages (by time periods, locations and months) of the Ice Harbor type fishway installed in the Gongju weir using traps. The monitoring were monthly conducted from June to October, 2012. The number of individuals which used fishway in September and October decreased than in June to August. Although no statistical significance was identified, many numbers of species and individuals were occurred at the trap installed at the left end of fishway than others. Fishes of more diverse size classes occurred at this trap as well. The number of collected individuals and water level of weir were positively correlated though they showed low correlation coefficient. Conversely, occurrence rate of fishes smaller than 70 mm of total length decreased with increasing water level of weir. fishway usage time of fish were different depends on ecological characteristics of each species. Various sizes of fishes can use fishway for their upstream migration. These results are useful for establishing management and evaluation plans of Ice Harbor type fishway in S. Korea.

• Journal of Nutrition and Health
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• v.44 no.5
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• pp.366-377
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• 2011

Glutathione S-transferase (GST) is a multigene family of phase II detoxifying enzymes that metabolize a wide range of exogenous and endogenous electrophilic compounds. GSTM1 and GSTT1 gene polymorphisms may account for inter-individual variability in coping with oxidative stress. We investigated the relationships between the level of lymphocyte DNA and antioxidative parameters and the effect on GST genotypes. GSTM1 and GSTT1 were characterized in 301 young healthy Korean adults and compared with oxidative stress parameters such as the level of lymphocyte DNA, plasma antioxidant vitamins, and erythrocyte antioxidant enzymes in smokers and non smokers. GST genotype, degree of DNA damage in lymphocytes, erythrocyte activities of superoxide dismutase, catalase, and glutathione peroxidase (GSH-Px), and plasma concentrations of total radical-trapping antioxidant potential (TRAP), vitamin C, ${\alpha}$- and ${\gamma}$-tocopherol, ${\alpha}$- and ${\beta}$-carotene, and cryptoxanthin were analyzed. Lymphocyte DNA damage assessed by the comet assay was higher in smokers than that in non-smokers, but the levels of plasma vitamin C, ${\beta}$-carotene, TRAP, erythrocyte catalase, and GSH-Px were lower than those of non-smokers (p < 0.05). Lymphocyte DNA damage was higher in subjects with the GSTM1- or GSTT1-present genotype than those with the GSTM1-present or GSTT1- genotype. No difference in erythrocyte antioxidant enzyme activities, plasma TRAP, or vitamin levels was observed in subjects with the GSTM1 or GSTT1 genotypes, except ${\beta}$-carotene. Significant negative correlations were observed between lymphocyte DNA damage and plasma levels of TRAP and erythrocyte activities of catalase and GSH-Px after adjusting for smoking pack-years. Negative correlations were observed between plasma vitamin C and lymphocyte DNA damage only in individuals with the GSTM1-present or GSTT1- genotype. The interesting finding was the significant positive correlations between lymphocyte DNA damage and plasma levels of ${\alpha}$-carotene, ${\beta}$-carotene, and cryptoxanthin. In conclusion, the GSTM1- and GSTT1-present genotypes as well as smoking aggravated antioxidant status through lymphocyte DNA damage. This finding confirms that GST polymorphisms could be important determinants of antioxidant status in young smoking and non-smoking adults. Consequently, the protective effect of supplemental antioxidants on DNA damage in individuals carrying the GSTM1- or GSTT1-present genotypes might show significantly higher values than expected.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1690-1695
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• 2001

Wheat straw was treated on laboratory scale with 4% urea at a moisture level of 50% along with different amounts of acetic acid (AA) to fix various levels of ammonia nitrogen (15, 30, 45 and 60%) evolved from urea and stored for 4 weeks. Chemical composition of the treated samples revealed a significant (p<0.01) increase in N content of the samples where AA was added. The N content of the ammoniated straw was only 1.21% which increased to 2.58 with the addition of AA to trap 30% $NH_3-N$. The concentration of free $NH_3-N$ in the straw was significantly (p<0.01) less when more than 15% $NH_3-N$ was trapped with AA. There was significant increase (p<0.01) in N disappearance and depression in NDF and hemicellulose disappearance, when AA was used to trap 30% $NH_3-N$. Large scale treatment of wheat straw with 4% urea at a moisture level of 50% along with AA (to trap 30% $NH_3-N$) increased the N content, but not as much as in laboratory scale treatment. In vivo experiment conducted on nine adult male buffaloes divided into three groups revealed no difference in the intake of DM, OM, NDF, ADF, cellulose and hemicellulose among group I (ammoniated straw), group II (AA treated ammoniated straw) and group III (AA treated ammoniated straw +1 kg barley grain), but the intake was significantly (p<0.05) more in groups where AA treated straw was fed as compared to only ammoniated straw fed group. However EE digestibility was depressed in group II. The digestibility of cellulose and hemicellulose both depressed significantly (p<0.05) in group II and III as compared to group I. Animals in all the 3 groups showed positive nitrogen balance and it was significantly more in group II and III as compared to group I. DCP intake was significantly (p<0.05) more in group II and III as compared to group I, but there was no significant difference among the three groups in TDN intake. It can be concluded that AA (to trap 30% $NH_3-N$) is effective in capturing the excess ammonia released during urea ammoniation of straw and improving its nutritive value, as well as animal performance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.3
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• pp.182-187
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• 2011

In this paper, PBTI characteristics of NMOSFETs with La incorporated HfSiON and HfON are compared in detail. The charge trapping model shows that threshold voltage shift (${\Delta}V_{\mathrm{T}}$) of NMOSFETs with HfLaON is greater than that of HfLaSiON. PBTI lifetime of HfLaSiON is also greater than that of HfLaON by about 2~3 orders of magnitude. Therefore, high charge trapping rate of HfLaON can be explained by higher trap density than HfLaSiON. The different de-trapping behavior under recovery stress can be explained by the stable energy for U-trap model, which is related to trap energy level at zero electric field in high-k dielectric. The trap energy level of two devices at zero electric field, which is extracted using Frenkel-poole emission model, is 1,658 eV for HfLaSiON and 1,730 eV for HfLaON, respectively. Moreover, the optical phonon energy of HfLaON extracted from the thermally activated gate current is greater than that of HfLaSiON.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.41-46
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• 1992

To perform a long-term ambient sampling study at a residential site, an air sampler was constructed to collect 24-hour integrated air samples suitable for the volatile organic compounds (VOCs) analysis. It includes an esthetically acceptance due to proximity to homes, as fell as providing the required sampling specifications. The VOCs sampler accomodates four 5/8 "stainless steel(SS) traps packed with adsorbent(Tenax) and is capable of four flow rates in the range of 5 to 50 cc/min. Sintered metal filters(10 micrometer) were directly connected to the inlet of the trap adapters. Additional specifications include: 1) constructed of organically inert materials, 2) weatherproof, 3) battery operated, 4) collecting of VOCs at a breathing zone level, and 5) quiet operation with micro diaphragm pumps wrapped by the sponge. The pump/battery system was separated from the sampling shelter. Sound levels measured for this system were below permissible sound levels (NJDEP) at a residential site. The sampler has been successfully operated at both ground level in a residential area and on the roof of a one story elementary school.hool.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.13-16
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• 1998

An anomalous current characteristics which show the superposition of a low current level and high current level at the subthreshold region when SONOSFETs are in memory states were investigated. We have assumed this phenomena were resulted from the effect of parasitic transistors by LOCOS isolation and were modeled to a parallel equivalent circuit of one memory transistor and two parasitic transistors. Theoretical curves are well fitted in measured log I$_{D}$-V$_{G}$ curves independent of channel width of memory devices. The difference between low current level and high current level is apparently decreased with decrease of channel width of devices because parasitic devices dominantly contribute to the current conduction with decrease of channel width of memory devices. As a result, we concluded that the LOCOS isolation has to selectively adopt in the design of process for charge-trap type NVSM.VSM.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.357-367
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• 2001

The purpose of this study was to investigate the alveolar bone turnover in diabetic rat, and to compare the alveolar bone turnover during tooth movement in diabetes with that in normal control Eighty Male Sprague-Dawley strain rats(8th week) were divided into normal control(N), normal-tooth movement (N-tm), diabetes(D), and diabetes-tooth movement(D-tm) groups. Eighteen days before the start of the experiment, diabetes was induced with a single injection of streptozotocin 50 mg/kg of body weight in citrate buffer as vehicle via the tail vein. Maxillary first molars of rats were moved mesially by 40 grams of the closed coil spring. Experimental animals were sacrificed after 1d, 3d, 7d, and 14d experimental period, and the alveolar bone around the maxillary first molars were assayed biochemically for acid phsophatase(ACP) and tartrate-resistant acid phosphatase (TRAP) as bone resorption markers, and alkaline phosphatase(ALP) and osteocalcin(OC) as bone formation markers. TRAP and OC concentration in serum and alveolar bone of D group were lower than those in N group, and especially OC concentration decreased mote following diabetes prolonged, which showed the decreased skeletal and alveolar bone resorption and formation potential in diabetic rats. In N-tm group compared with N group, alveolar bone ACP and TRAP concentrations were highest at 1d and 3d(p<0.01), decreased after then, and showed lowest at 14d, and alveolar bone OC concentration was higher at 3d, 7d, and 14d(p<0.001) and showed a tendency of peak level at 7d. which showed the peak of concentration of bone resorption markets at 1d-3d and those of bone formation markers at 7d. In D-tm group compared with N group, alveolar bone ACP and TRAP concentrations were higher at 3d, 7d and 14d(p<0.001), and tended to reach peak value at 7d and persisted through 14d, and alveolar bone ALP and OC concentration increased but not different from that of N group. The amount of tooth movement in D group were greater than that of N group at all experimental period. Those results were suggested that during diabetes, the alveolar and skeletal bone undergo low bone turnover and the mote amount of tooth movement, hut because the peak time of alveolar bone resorption activity was delayed and sustained in longer period of tooth movement and alveolar bone formation activity is lower than that of normal tooth movement, the periodontal space is supposed to be larger doting tooth movement.