• Journal of Korean Society on Water Environment
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• v.36 no.5
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• pp.445-452
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• 2020

Tributary is a part of life space for people and a very important place that accommodates rest recreation and other daily activities. absolutely insufficient basic data about water quality and flow rate are available for basin management. Efficient water and basin management systems, which are also supported by local residents can be established by securing such basic data of major tributaries in the Nakdong river system. In this study, the fluctuation characteristics of upstream and downstream water pollution levels were compared using the measurement results of the water environment measurement network and the tributary monitoring project for the gyeseong-stream and Hwapo-stream in the Nakdong-miryang watershed. In 2017, when water pollution is the highest, it was confirmed that the annual average rainfall was the lowest. Although the upstream and downstream water quality tendencies of the Gyeseong-stream are similar, the water quality concentrations of the Gyeseong-stream are relatively different. But although the Hwapo stream has various causes of pollution, there was not much difference in the level of pollution between the upper and lower streams. In addition, both rivers need the ability to purify rivers by securing sufficient water for river maintenance, and if the correlation between water quality items can be inferred through continuous monitoring of tributaries where the aspect of water quality change is unclear, water quality management Determined to be efficient operation.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.2
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• pp.149-157
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• 2020

Purpose : The purpose of this study was that For high school students in Busan, in order to provide basic data in selecting dental hygienists by establishing the correct perception and image of dental hygienists by identifying the image of dentists and career doctors who will choose dental hygienists. Methods : The comparison of group differences with dental hygienists' images was analyzed with independent sample t-test and one-way ANOVA. Correlation between image factors of dental hygienists was analyzed using Pearson's correction coefficient. Results : The image for dental hygienists averaged 3.87 points overall, while the average for each area of the image was 4.09 points for professional images, 4.07 points for business images, 4.08 points for personal images and 3.28 points for social images. When choosing a career path, 18.8 percent said they would not consider dental hygiene, and if they said they would consider dental hygiene, both work, professional, personal and social images were significantly high (p<.05). Professional and professional images (r=.975, p<.05) in the correlation between factors of dental hygienist images, personal and professional images (r=.942, p<.05), social and professional images (r=.865, p<.05), business and personal images (r=.924, p<.05), business image and social image (r=.858, p<.05), personal and social images (r=.882, p<.05) expressed a statistically significant amount of correlation. Conclusion : The study found that high school students' image of dental hygienists was rather positive, but their social image was rather low, and most students did not consider dental hygiene. Therefore, specific measures will be needed to build a desirable image for dental hygienists and positively recognize dental hygienists with active promotion and career experience for dental hygienists in the future.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.219-222
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• 1985

Fatty acid patterns were determined for 11 and 19 brands of household margarines from the local markets in Korea in 1983 and 1984, respectively. Gas-liquid chromatographic analyses on OV-275 column showed that the average content of total trans fatty acids was 18% ranging from 6.2 to 35.5% for the margarines produced in 1983. The prototype of trans fatty acids was trans-octadecenoic acid. There was a small amount of c, t-or t, c-octadecadienoic, whereas there were practically no t, t-octadecadienoic acid. Trans fatty acids was increased in proportion to linoleic acid contents. For the margarines produced in 1984.. percentage of trans fatty acids tended to decrease, while that of linoleic acid was increased as compared with the corresponding values for the 1983 products. Thus, the P/S ratio was increased markedly in the soft type margarines produced in 1984. However, Korean margarines contained seemingly less linoleic acid than that contained in Japanese margarines.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.455-461
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• 2008

Enhanced Distributed Channel Access (EDCA) is a channel access scheme adopted by the IEEE 802.11e draft standard for QoS-enabled wireless local area networks. It classifies traffic into separate Access Categories (ACs) and achieves service differentiation by allowing each AC to have its own values of channel access parameters. This paper proposes a scheme to dynamically adapt the EDCA parameters to traffic environment so that they both maximize the throughput of non real-time traffics and meet the delay and throughput constraints of real-time traffics. For this purpose, we develop a design algorithm for efficient exploration of the EDCA parameter space. Using the algorithm, we derive a Pareto curve fur delay-throughput trade-off in each anticipated traffic environment. The Pareto database can then be used to optimally adjust the parameter according to the traffic environment and administrative policies. Simulation results show that compared with the default parameter configuration, the proposed scheme is better for delay, throughput guarantee and can improve the throughput of non real-time traffics by 12% on average.

• Research in Plant Disease
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• v.7 no.2
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• pp.102-106
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• 2001

Currently the rice false smut caused by Ustilaginoidea virens (Cooke) Takah. has occurred widely in Korea. A survey on the disease incidence at rice fields in 8 inland provinces was carried out in 2000, showing that the disease occurred at 104 (7.5%) out of 1,152 rice fields examined, ranging from 1.5% to 13.7% in provincial average. It was found that the disease incidence was greatly affected by local weather conditions and rice cultivars. In case of the most susceptible cultivar Namchunbyeo, the disease incidence was only about 1.3% in Icheon, while it was over 20% in Namwon which had weather conditions of the shorter sunshine period (about 64%) and the higher amount of precipitation (about 130%) during the rice cultivation than Icheon. In Icheon, artificial inoculation of the pathogen failed to induce the disease, probably because of the weather conditions unfavorable to the disease development, which also suggests that its incidence may be dependent on the weather conditions. Susceptibility of rice cultivars to the disease varied greatly; eight resistant cultivars including Heukjinjubyeo were not damaged by the disease, but 2 cultivars including Geumnambyeo and Namchunbyeo were severely damaged, having more than 20% of the disease incidence. Among chemicals tested fur the control of the rice false smut tebuconazole WP showed the highest control efficacy of 83∼88% on cvs. Geumnambyeo and Namchunbyeo. Other chemicals such as azoxystrobin WP and ferimzone WP also effectively suppressed the disease development in the field trials.

• Archives of Plastic Surgery
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• v.39 no.4
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• pp.360-366
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• 2012

Background Coverage of defects of the pretibial area remains a challenge for surgeons. The difficulty comes from the limited mobility and availability of the overlying skin and soft tissue. We applied variable pedicled perforator flaps to overcome the disadvantages of local flaps and free flaps on the pretibial area. Methods Eight patients who had the defects in the anterior tibial area were enrolled. Retrospective data were obtained on patient demographics, cause, defect location, defect size, flap dimension, originating artery, pedicle length, pedicle rotation, complication, and postoperative result. The raw surface created following the flap elevation was covered with a split thickness skin graft. Results Posterior tibial artery-based perforator flaps were used in five cases and peroneal artery-based perforator flaps in three cases. The mean age was 54.3 and the mean period of follow-up was 6 months. The average size of the flaps was 63.8 $cm^2$, with a range of 18 to 135 $cm^2$. There were no major complications. No patients had any newly developed functional deficit of the lower leg. Conclusions We suggest that pedicled perforator flaps can be an alternative treatment modality for covering pretibial defects as a simple, safe and versatile procedure.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.603-609
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• 2013

Background Although the conventional direct brow lift operation provides a simple means of managing lateral brow ptosis, the scars produced have been unacceptable. However, using the modifications proposed here, scarring showed remarkable improvement. This article reviews our experiences with the presented technique, mainly with respect to postoperative scarring. Methods Measured amounts of supra-eyebrow skin and subcutaneous fat were excised en bloc in the conventional manner under 'hyper-hydrated' local infiltration anesthesia. The lower flap and the edge of the upper flap were undermined above the muscular plane, and the orbicularis oculi muscle was directly suture-plicated and suspended upward to the distal frontalis muscle. Skin closure was performed in a basic plastic surgical manner. Results From April 2007 to April 2012, a consecutive series of 60 patients underwent surgery using the above method. The average width of the excised skin was 8 mm (range, 5-15 mm) at the apex of the eyebrow. Preoperative complaints were resolved without occurrence of significant complications. The surgical scars showed remarkable improvement and were negligible in the majority of the cases. Conclusions The direct brow lift operation combined with plication/suspension of the superior and lateral portion of the orbicularis oculi muscle provides a simple, safe, and predictable means of correcting lateral brow ptosis. The scars were acceptable to all of the patients. For proper management of the frontalis tone, upper blepharoplasty and/or repair of eyelid levator function must be considered in addition to brow lift procedures.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.2
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• pp.130-136
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• 2010

For stability analysis of the lumbar spine, the hypothesis presented is that the disc has stress sensors driving feedback mechanism, which could react to the imposed loads by adjusting the contraction of the muscles. Fusion in the motion segment of the lumbar spinal column is believed to alter the stability of the spinal column. To identify this effect finite element (FE) models combined with optimization technique was applied and quantify the role of each muscle and reaction forces in the spinal column with respect to the fusion level. The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Vertebral body and pelvis were modeled as a rigid body and the rib cage was constructed with rigid truss element for the computational efficiency. Spinal fusion model was applied to L3-L4, L4-L5, L5-S1 (single level) and L3-L5 (two levels) segments. Muscle architecture with 46 local muscles was used as acting directions. Minimization of the nucleus pressure deviation and annulus fiber average axial stress deviation was selected for cost function. As a result, spinal fusion produced reaction changes at each motion segment as well as contribution of each muscle. Longissimus thoracis and psoas major muscle showed dramatic changes for the cases of L5-S1 and L3-L5 level fusion. Muscle force change at each muscle also generated relatively high nucleus pressure not only at the adjacent level but at another level, which can explain disc degeneration pattern observed in clinical study.

• International Journal of Highway Engineering
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• v.12 no.2
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• pp.91-97
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• 2010

This study started from the problem recognition of climbing lane installed in Korea roads. Because design standards of climbing lane installed don't match traffic pattern of korean drivers, coefficient of utilization of climbing lane is low and merging section between climbing lane and main lane has traffic accident possibilities. For this, brand-new design standards developed from the present lane design criterion, taper lenghs, and traffic signs, then field adoption test was carried out to prove the effectiveness. As a result, coefficient of utilization of climbing lane and average traffic velocity in climbing section are improved and the economic analysis also shows that brand-new standards has high feasibility for low cost. In case of broad application to not only expressway but national and local road based on the study, it could be a significant contribution to traffic flow improvement.

• Journal of Chest Surgery
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• v.26 no.1
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• pp.32-35
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• 1993

During the period from September 1989 through December 1992, 118 cases of coronary arterial bypass graft were performed at Department of Cardiothoracic Surgery, Asan Medical Center. Twenty-one of these had history of recent or remote percutaneous transluminal coronary angioplasty. They consisted of 13 males[age,58.7 + 5.4 years] and 8 females[age, 63.6 + 2.8years] with the mean age of 60.6. History of old myocardial infarction was noted in 24%[5/21] of the patients and congestive heart failure in 2 cases. The angina by type of presentation is unstable in all of the patients. The patterns of involvement of coronary arterial disease were left main disease[1], single vessel disease[5], double vessel involvement[10], and triple vessel involvement[5]. We performed 4 cases of single bypasses, 7 cases of double, 8 cases of triple, and 2 cases of quadruple bypasses. Total of 51 grafts[LIMA:12, RSVG:39] were inserted in 21 cases with average of 2.4 grafts per patient. The methods of myocardial protection were cold blood cardioplegia[8 cases], intermittent aortic occlusion[11], and continuous coronary perfusion with local coronary sharing[2]. There were no operative or late death. The only cardiac complication was 1 case of low cardiac output required IABP. The other complications were 1 case of sternal wound infection and 1 case of postoperative bleeding required reoperation. And there was no case of perioperative myocardial infarction. Postoperatively, 3 cases of recurrent angina were detected at 5, 7, and 18months after surgery. One of them was managed successfully with repeat PTCA[who was recurred 18 months postoperatively], and the other two with medication. I conclude that we can approach the patients more aggressively with PTCA, because of our acceptable operative risks.