• Journal of Environmental Health Sciences
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• v.29 no.1
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• pp.74-83
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• 2003

Microcystin, stable compounds with circular heptapeptides, is presented inside cyanobacterial cell. So far, over 30 types have been known to exist and microcystin-LR, RR among them are the most potent toxin compound. By this reason, a strong oxidant, ozone was used in this study to remove the microcystins produced by cyanobacteria. Removal efficiency of microcystin at M water treatment plant was also evaluated. Microcystin concentration was determined by protein phosphatase inhibition assay. The results showed that dissolved microcystin in raw water detected in the range of 0.011-0.028 ㎍ Microcystin-RR equivalent/l. Above 98% of microcystin was removed through overall treatment system. Therefore, the water treatability of M treatment plant seemed to be excellent. Removal efficiency of microcystin according to unit process varied as characteristics of raw water such as DOC, UV/sub 254/ and turbidity. Removal efficiency of microcystin by ozonation was investigated in laboratory according to contact time and ozone dose. Dissolved microcystin was increased by twice fold according to ozone contact time, but increased by fifth fold according to ozone dose. So, changing of ozone dose more affected microcystin release than changing of ozone contact time. Behavior of microcystin by ozonation was similar to that of DOC, and residual ozone concentration gave influence to removal ratio of microcystin. In conclusion, single ozone treatment wasn't effective on microcystin removal in case of water containing a lot of cells. Therefore, it's more effective to use ozonation process after the removal of cyanobacterial cells in advance.

• Journal of Chest Surgery
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• v.31 no.7
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• pp.703-710
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• 1998

We treated 654 patients with simultaneous bilateral sympathectomy for essential hyperhidrosis from March 1989 to September 1997(354 males and 300 females). The exposure afforded by thoracoscopy is actually superior to that seen at the time of either thoracotomy or axillary thoracotomy. The use of single-lumen intubation with alternating partially collapsed lung by CO2 inflation resulted in shorter anesthesia, shorter operative time, and shorter hospitalization. 2-mm extended thoracoscopic T2-sympathectomy is not only a time-saving method but also a very simple and effective one in the treatment of hyperhidrosis by experienced surgeons. The modification on our technique of thoracoscopic sympathectomy as described allowed us to significantly improve our previous results. A majority of the patients were relieved, and over 95% were satisfied initially.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.2972-2991
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• 2016

WLAN is the best choice in the place where complex network is hard to set up. Intelligent terminals are more and more assembled in some areas now. However, according to IEEE 802.11n/802.11ac, the access-point (AP) can only serve one user at a single frequency channel. The spectrum efficiency urgently needs to be improved. In theory, AP with multi-antenna can serve multiple users if these users do not interfere with each other. In this paper, we propose a user clustering scheme that could achieve multi-user selection through the mutual cooperation among users. We focus on two points, one is to achieve multi-user communication with multiple antennas technique at a single frequency channel, and the other one is to use a way of distributed users' collaboration to determine the multi-user selection for user clustering. Firstly, we use the CSMA/CA protocol to select the first user, and then we set this user as a source node using users' cooperation to search other proper users. With the help of the users' broadcast cooperation, we can search and select other appropriate user (while the number of access users is limited by the number of antennas in AP) to access AP with the first user simultaneously. In the network node searching, we propose a maximum degree energy routing searching algorithm, which uses the shortest time and traverses as many users as possible. We carried out the necessary analysis and simulation to prove the feasibility of the scheme. We hope this work may provide a new idea for the solution of the multiple access problem.

• Journal of Ocean Engineering and Technology
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• v.34 no.5
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• pp.351-360
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• 2020

Of late, demand for test sites for marine equipment such as ASV, AUV, ROV, and various underwater sensors is increasing. The authors have focused on an oscillating water column (OWC), which is being constructed near Chagwido Island Jeju, as one of the test-sites. The main objective of the OWC is to produce wave energy and develop technologies. It has been built in the sea approximately 1 km off the coast. It has berth accommodation and some rooms that can be used as laboratories. To investigate the feasibility of its usage as a test site for marine equipment, we acquired bathymetric data around the OWC by using a multi-beam echo sounder and a single-beam scanning sonar. The accessibility of the OWC from nearby ports and the use of support vessels or ships were also investigated. 3D point cloud data from the multi-beam echo sounder and 2D acoustic images from the scanning sonar are expected to be used as references for identifying changes over time. In addition, through these experiments, we derived a procedure to use this facility as a test site by using the IDEF0 functional modelling method. Based on this preliminary investigation and previously reported examples, we determined the general conditions and preferences for evaluating the performance of various marine equipment heuristically. Finally, we developed five applications that were derived from this investigation.

• The Journal of Korean Medicine
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• v.36 no.2
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• pp.43-49
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• 2015

Objectives: We evaluated the effect of the traditional Korean medical therapy of catgut-embedding therapy in patients with carpal tunnel syndrome (CTS). Methods: Thirteen patients(20 hands) with CTS underwent catgut-embedding therapy once per week for a total of 1-4 sessions. We measured the time to tingling in the fingers on performing Phalen's test. We also had patients use a visual analog scale (VAS) to indicate the severity of tingling. We also asked about the awakening time at night due to pain and tingling. We controlled the treatment as being limited to four sessions. Even if a patient had not been treated for four sessions, we ended the patient's treatment if symptoms resolved. Results: Patients who received catgut-embedding therapy showed significant improvements in the clinical symptoms of CTS. After treatment, in a total of 19 hands, the status of fourteen was changed from positive to negative in Phalen's test and the average of tingling occurrence time in that test was delayed. Among the 20 hands, the VAS in eight hands changed to zero and the average of VAS score decreased. Furthermore, in nine patients, four could sleep well without the use of a splint. Conclusions: Patients undergoing this traditional Korean medical therapy showed alleviation of finger tingling after even a single treatment. We thus concluded that this traditional Korean catgut-embedding therapy, may be effective for treating CTS. However, to confirm the effects of catgut-embedding therapy on CTS, further tests are required, including under the defined, strict conditions of a randomized controlled trial.

• Therapeutic Science for Rehabilitation
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• v.4 no.2
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• pp.51-62
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• 2015

Objectives : This research was conducted to plan a strategy on the activities for ADHD who want to improve, and to use the strategy to find out how it influences the occupational performance when applying Cognitive Orientation to a daily Occupational Performance (CO-OP) approach. Methods : A single Subject AB design was employed. The subjects was one children with ADHD. The experiment consisted of 10 sessions spread over 7 weeks. The objective selected through COPM with guardians was improvement of chopstick use by children. In the course of the intervention, the overall CO-OP process was explained, continued analysis of performance and practice were encouraged in order to learn the skill of chopstick use, and guidance was given for DSS. Performance was measured by the time to move beans from one plate to another, starting from when the chopsticks were picked up. Results : The time to pick up the beans was 22.3s before the intervention, which was decreased by 7.2s to 15.1s after the intervention. The parents' COPM score showed an improvement of 3 points for performance and 4 points for satisfaction, demonstrating a clinically significant change. Conclusion : This study provides evidence that CO-OP is beneficial in occupation performance in children with ADHD.

• Journal of IKEEE
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• v.24 no.1
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• pp.46-51
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• 2020

With Wi-Fi and Bluetooth connectivity becoming more common in today's handheld mobile devices, single-chip multi-radio combo-modules, which integrate two or more heterogeneous wireless radios on a single chip, are becoming more and more popular. The key requirement for combo solutions is that the quality of the user experience (QoE) must not be compromised by degrading connectivity performance. Therefore, characterizing and understanding the behaviour of combo-module is of vital importance to ensure this requirement in various environments. In this paper, we investigate the impact of the use of combo-modules on the performance of mobile video streaming over a Wi-Fi network. Our study reveals that the use of combo-modules incurs considerable side effects on QoE for mobile video streaming applications when the Wi-Fi and Bluetooth operate at the same time in the 2.4GHz ISM band. We reveal that rate-based adaptive algorithms, including the most popular adaptive bitrate streaming MPEG-DASH, is more severely affected by this phenomenon than buffer-based adaptive algorithms.

• Journal of Trauma and Injury
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• v.34 no.3
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• pp.162-169
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• 2021

Purpose: For severe lung injuries or acute respiratory distress syndrome that occurs during critical care due to trauma, extracorporeal membrane oxygenation (ECMO) may be used as a salvage treatment. This study aimed to describe the experiences at a single center with the use of ECMO in trauma patients. Methods: We enrolled a total of 25 trauma patients who were treated with ECMO between January 2015 and December 2019 at a regional trauma center. We analyzed and compared patients' characteristics between survivors and non-survivors through a medical chart review. We also compared the characteristics of patients between direct and indirect lung injury groups. Results: The mean age of the 25 patients was 45.9±19.5 years, and 19 patients (76.0%) were male. The mean Injury Severity Score was 26.1±10.1. Ten patients (40.0%) had an Abbreviated Injury Scale (AIS) 3 score of 4, and six patients (24.0%) had an AIS 3 score of 5. There were 19 cases (76.6%) of direct lung injury. The mortality rate was 60.0% (n=15). Sixteen patients (64.0%) received a loading dose of heparin for the initiation of ECMO. There was no significant difference in heparin use between the survivors and non-survivors (70% in survivors vs. 60% in non-survivors, p=0.691). When comparing the direct and indirect lung injury groups, there were no significant differences in variables other than age and ECMO onset time. Conclusions: If more evidence is gathered, risk factors and indications will be identified and we expect that more trauma patients will receive appropriate treatment with ECMO.

• Korean Journal of Poultry Science
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• v.36 no.1
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• pp.85-88
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• 2009

One of the mitochondrial genes, called cytochrome c oxidase I (COI), has been widely used for the species identification (called bio-barcode) in birds. In this study, the bio-barcode has been applied to chicken breeds in Korea whether it also can be used as a molecular marker for breed identification. Data indicated that Korean native chicken has the mixed SNP (single nucleotide polymorphism) patterns between White Leghorn (Layer) and Cornish (Broiler) and ultimately, it can not be used as the marker for breed identification. However, this result indicates the mixed use of the Korean native chicken, since it has been used for dual purpose for producing meat and egg for a long time. In order to use as a marker for species identification, more reliable mitochondrial and/or nuclear DNA markers need to be developed.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.351-359
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• 1991

The current LINAC technique for radiosurgery utilizes a single isocenter approach with multiple noncoplanar arcs. This approach results in spherical dose distributions in the target. Many arteriovenous malformations and tumors suitable for radiosurgical treatment have non-spherical or irregular shapes. The basic approach presented in this paper is to use two or multiple isocenters with standard arcs to shape irregular target volumes through the use of multiple spherical targets. Selection of reasonable irradiation parameters in the first stage is critical to the success of real-time optimization. A useful guideline for optimum isocenter separation and collimator size is developed to shape the target margin uniformly with an desired isodose surface for an elongated target. The implementation of multiple isocenters with three dimensional dose model and application of multiple isocenters approach to several cases are discussed.