• The Korean Journal of Ecology
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• v.19 no.6
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• pp.563-573
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• 1996

Macroinvertebrate contribution to the leaf litter breakdown of Carpinus cordata was estimated at headwater streams at Mt. Jumbong (38°03'N, 128°25'E) during spring and winter spring by using two types of litter bag. Coarse-mesh bags with 10 g of leaf letter were placed in a 1st-order stream in April (the spring experiment) and December 1995 (the winter-spring experiment). Fine-mesh bags with 5 g of leaf letter were placed in a nearby 3ed-order steam. The breakdown of Carpinus in coarse-mesh bags was rapid, and, in terms of season, leaf litter processed rapidly during spring. daily mass loss rates of leaf litter (-k±1 SE) were highest for coarse-mesh bags in the spring experiment (-0.0429±0.0048), followed by coarse-mesh bags in the winter-spring (-0.0146±0.0014), fine-mesh bags in the spring (-0.0078±0.0004), fine-mesh bags in the winter-spring experiment (-0.0054±0.0005). Macroinvertebrate contribution to the litter breakdown was estimated by the difference of % leaf letter remaining between coarse -mesh bage and fine-mesh bags. Although shredders were more abundant during the winter-spring, their contribution was greater during the spring (50%) than the winter-spring (22∼33%). This result appeared to be due to the change in the chemical composition of leaf letter during processing, and to the seasonal growth patterns of major shredder taxa.

• Journal of Environmental Science International
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• v.13 no.6
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• pp.571-579
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• 2004

There is a need to improve the efficiency of the existing sanitary treatment facilities, because the effluent standard becomes more stricter and septic sludge increased. Thus, operating processes of sanitary treatment system in M city changed with installation of additional facilities. Process modifications were as follows: Dilution water was added to the next process after primary aeration tank. Some secondary sedimentation sludge was recycled to primary aerator so that most of the organics were stabilized in primary aeration tank under automatic control of dissolved oxygen. The line of effluent from dewatering process flowing to the activated sludge tank was changed to the primary aerator. The primary sedimentation sludge line was linked to a thickener. Polymer was added to the activated sludge tank. The effluent of primary aerator and aerobic digester was recycled from the 5th to the 1st sector. As consequencies of above process modifications, the improvement of removal efficiency was achieved as BOD 54%, COD 42%, SS 61%, T-N 39%, and T-P 12%, respectively.

• Journal of Ecology and Environment
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• v.32 no.1
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• pp.19-25
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• 2009

An arthropod community in a rice ecosystem was surveyed to determine the impact of two insecticides frequently used in Korean rice ecosystems: carbofuran 3GR, which targets the rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae) in the early season and fenobucarb EC, which targets the brown planthopper, Nilaparvata lugens ($St{\aa}l$) (Hemiptera: Delphacidae) in the mid- and late seasons, respectively. Overall, the application of the insecticides reduced density of total arthropods by 48.4% compared to the untreated field, but their impact on each functional group were different. Carbofuran GR treatment on 1 June reduced the L. oryzophilus population significantly until mid-season. The population of filterfeeding chironomids was also reduced by 50%, whereas the spider population was less disturbed. Fenobucarb EC treatment on 16 August significantly reduced N. lugens and detrivorous entomobryid populations until the late season. Both web-building and wandering spiders were also significantly disturbed by fenobucarb EC although the impact differed according to their behavioral differences. While the population of web-building spiders significantly decreased over time, that of wandering spiders recovered from the disturbance a few weeks later.

• ALGAE
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• v.30 no.2
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• pp.89-101
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• 2015

Ecklonia cava Kjellman is a common kelp found in shallow subtidal in warm-temperate waters in the northwest Pacific Ocean. This species has shown substantial morphological variation along with subsistence in different locations and local environments. We quantified the magnitude of morphological variation of E. cava from six populations along ~700 km of coastline from Jeju Island to Dokdo in Korea. In addition, we examined genetic distance among the populations using random amplified polymorphic DNA (RAPD) analysis. Most morphological characteristics investigated were significantly different among locations. Multivariate analyses indicated two phenetically distinct groups (nearshore, sheltered vs. offshore, exposed), indicating wave exposure with turbidity are presumably major factors for the separation. With RAPD data, results of Nei's diversity (H) and AMOVA showed considerable variations in within- and between-populations. Pairwise ${\Phi}_{ST}$ and $N_m$ values indicated moderate gene flow between the six locations. Results of Nei's analysis revealed three genetically distinct groups, not consistent with the morphological groupings, indicating that a time gap may exist between morphological and genetic variations. This study also suggests dispersal distance of this kelp may be longer than what is commonly thought and genetic similarity in the populations was largely reflected by the direction of ocean current rather than just geographical distance.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.116-121
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• 2012

In recent years, world is faced with a transportation energy dilemma, and the transportation is dependent on a single fuel - petroleum. However, Hybrid Electric Vehicle(HEV) technology holds more advantages to reduce the demand for petroleum in the transportation by efficiency improvements of petroleum consumption. Therefore, there is a trend that lower gear noise levels are demanded in HEV for drivers to avoid annoyance and fatigue during operation. And meshing transmission error(T.E.) is the excitation that leads to the tonal noise known as gear whine, and radiated gear whine is also the dominant source of noise in the whole gearbox. This paper presents a method for the analysis of gear tooth profile and lead modification, and the predictions of transmission error and load distribution are shown under one loaded torque for the 1st gear pair of HEV gearbox. The test is also obtained before tooth micro-modification under the torque. At last, the appropriate tooth modification is used to minimize the transmission error and load distribution under the loaded torque. It is a good approach which the simulated result is used to improve the design in order to minimize the radiation gear whine noise.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.3
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• pp.174-178
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• 2009

Many radiopharmaceuticals have been developed and wildy used in the imaging cardiac function. Myocardial perfusion imaging (MPI) is a well established noninvasive method of assessing coronary blood flow and has been widely used in patients diagnosed or suspected with coronary artery diseases. The innovation of radiopharmaceuticals used in the cardiac imaging is one of the most important contributors to the development of nuclear cardiology. Thallium-201 and various technetium-99m agents have been globally used for myocardial perfusion SPEG, and N-13 ammonia (13NH3), rubidium-82 (82Rb), 0-15 water (H2150) for myocardial perfusion PET. As well as the cardiac perfusion studies, new radiopharmaceuticals that visualize fat metabolism or receptors of the sympathetic nervous system have successfully been applied to clinical practice. Useful information can be obtained for diagnosing coronary artery disease, evaluating patients' condition, or assessing therapeutic effects. In this review, we describe the characteristics and clinical usefulness of radiopharmaceuticals used for cardiac SPEG and PET.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.424-430
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• 2012

Densities, viscosities, refractive indices and speed of sounds of the binary mixtures of Acetophenone with Ethylchloroacetate were measured over the entire mole fractions at (303.15, 313.15 and 323.15) K. From these experimental results, excess molar volume $V^E$, viscosity deviation ${\Delta}{\eta}$, refractive index deviation ${\Delta}n_D$, deviations in speed of sound ${\Delta}u$, deviations in isentropic compressibility ${\Delta}k_s$ and excess intermolecular free length ${\Delta}L_f$ were calculated. The viscosity data have been correlated with the equations of Grunberg and Nissan, Hind et al., Tamura and Kurata, Katti and Chaudri, Sedgwick, Krishnan-Laddha and McAllister. The thermo physical properties under study were fit to the Jouyban-Acree model. The excess values were correlated using Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. It was found that in all cases, the data obtained fitted with the values correlated by the corresponding models very well. The results are interpreted in terms of molecular interactions occurring in the solution.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.248-257
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• 2016

The international collaboration on marine biodiversity increases in the proportion of the world's scientific papers produced with more than one international author, 2006-2010. The number of scientific papers from 2006 to 2010 describing "marine new species (or spec. nov., n. sp.)" published 401 (international ranking : $13^{th}$) by S. Korea, 824 ($7^{th}$) by China, 1,249($5^{th}$) by Japan, 1,282($3^{rd}$) by Austrailia, and 3,679 ($1^{st}$) by United States. The papers having an international co-authorship account for 52.0% by S. Korea, 79.0% by China, 67.0% by Japan, 81.0% by Australia at the same period. The proportion of national publication output produced in collaboration with other countries differs proportionately between countries. In S. Korea, the overall numbers of international collaboration were not growing significantly. Both in Japan and China, an overall numbers of international collaboration increased well in accordance with the proportion of national output with international collaboration.

• The Journal of Internal Korean Medicine
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• v.41 no.1
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• pp.29-43
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• 2020

Objectives: The purpose of this study was to summarize current research trends and results regarding acupuncture treatment for hypertension. Methods: Articles published from 2009 to 2019 were searched on domestic databases (OASIS, NDSL, RISS) and PubMed using the keywords 'Hypertension', 'Hypertensive', 'Acupuncture', 'EA' (electroacupuncture), 'Autonomic nervous system', 'ANS', 'CVD' (cardiovascular disease), '고혈압', '침', '전침', and '자율신경계'. The studies were analyzed according to the year, type of study (domestic or foreign articles, nationality of the first author), acupuncture type for human and animal studies, BP (blood pressure) measurement, and acupuncture intervention. Results: In total, 21 articles were selected. There were 8 randomized controlled trials (RCTs), 3 non-randomized controlled trials (nRCTs), 2 before-after studies, 1 case series, and 7 animal studies. Manual acupuncture (11 articles) was most frequently used, and ST36 (足三里) was most frequently used in human studies. In 18 of 21 articles, acupuncture was reported as effective in lowering systolic blood pressure (SBP) or diastolic blood pressure (DBP) in hypertensive patients. Conclusions: Acupuncture treatment for hypertension is deemed useful. Further studies are necessary for application of acupuncture therapy in clinical practice.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6185-6187
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• 2013

Cervical cancer has emerged as a major public health problem in Lucknow and New York in the $21^{st}$ century. Cancer genetic studies are essential to identify/stratify disease-susceptible individuals in a population-based cohort. Sample size homogeneity and North Indian caste in female urology genetic-studies are significant issues in meaningful interpretation of data. A review of scientific literature using Pubmed database was conducted, including an assessment of cervical cancer genetic studies conducted as part of the author's doctoral dissertation at a premier Lucknow-based medical research Institute. Sample size numbers and caste criteria in the North Indian cohort ($N{\leq}400$ subjects) were evaluated with homogeneity in the sample cohort data set(s). Subgroup caste-stratification of North Indian cohort is equally essential, for instance, Brahmin (e.g. Pandey), Vaishya (e.g. Mittal), Rajput (e.g. Singh) and Kshudra (e.g. Yadav) during the conception and design of genetics-based studies. Sample size homogeneity in histopathologically confirmed case and control numbers and caste-based stratification in a North Indian cohort is essential in single nucleotide polymorphism (SNP) studies in cervical cancer susceptible populations to draw more definitive conclusions.