• Korean Journal of Optics and Photonics
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• v.21 no.6
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• pp.235-240
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• 2010

We fabricate highly birefringent photonic crystal fiber with new structure using a stack and draw method. Fabricated fiber has two big air holes, one at each side of the outside air cladding region, leading to core ellipticity during the drawing process. Birefringence of the fabricated Hi-Bi PCF is measured to be $2.29{\times}10^{-4}$ (at 1550 nm).

• Animal cells and systems
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• v.13 no.1
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• pp.71-78
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• 2009

To clarify the reproductive function of vibration signals in Hynobius, which has externally fertilized eggs, we quantitatively analyzed the body and tail undulations of male Korean salamanders (Hynobius leechii) in sixteen mating events. One large and one small male, and one female were used in each mating event. We analyzed behaviors recorded over a total of 3 hrs for each mating event; 2 hrs before and 1 hr after female's oviposition. Males touched females using their snouts or body trunk throughout the entire mating periods, but females touched males increasingly more after approximately 1 hr before oviposition. Males conducted body undulations more than 50 times per 10 minutes at a mean frequency of 0.64 Hz. Large males conducted more body undulations than small males, particularly on the tree twig where females attached their egg sacs. Males responded to other males' body undulation throughout the mating period by orienting their head towards, approaching, and touching the undulating male. Females only responded for about 10-20 min before ovipositing, and most responses were directed to the large male's body undulation. Males conducted tail undulations 3.0 times per 10 min at a mean frequency of 1.7 Hz and most tail undulations occurred after one male bit the other male. These results suggest that body undulations function in both male-female and male-male interactions, while tail undulations mainly functions in male-male competition. Also, male H. leechii appear to actively attract females, while females respond to the males only at times close to oviposition.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.378-381
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• 2011

The group management system with Wireless Sensor Network and android application is proposed in this paper. The proposed system was composed of personal devices with sensor nodes of WSN, manager device of android platform, and the web server. The sensor node used by each group member send a data packet to the manager device every 2 seconds. The leader device displays and transmits entire information to the web server. The web server represents these information through web page. Therefore, guardians can assure their group member's safety and security on the web page. The RSSI value of each sensor node converted by computed log-normal path loss model into distance value and displays on the manager device and the web page.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.109-114
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• 2020

In this study, the elevational distribution of breeding birds in Seoraksan National Park, Korea was investigated. Forty-six species of birds were documented from line transect surveys taken from Seorakdong at 230 m above sea level (a.s.l.) to the Daechungbong summit at 1708 m asl. Birdspecies richness and diversity were highest in Seorakdong and lowest at the Daechungbong summit. As elevation increased, bird species richness and diversity decreased, with a humped-shape trend being observed between 700 m and 1200 m a.s.l. Stepwise analyses revealed that breeding bird species diversity indices were significantly negatively correlated with elevation (r² = 0.327, P < 0.001) and positively correlated with vegetational coverage (r² = 0.324, P = 0.046). Higher elevations supported fewer birds than low and intermediate elevations. Projections at the local scale, including data on behavior and habitat use by birds, will be necessary for optimal conservation and management of the bird communities in Seoraksan National Park.

• Journal of Gastric Cancer
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• v.13 no.2
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• pp.121-125
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• 2013

Gastric cancer patients with acute disseminated intravascular coagulation experiences a rare but severe complication resulting in a dismal prognosis. We report a case of advanced gastric cancer complicated with disseminated intravascular coagulation with intractable tumor bleeding which was successfully treated with chemotherapy consisting of 5-fluorouracil and oxaliplatin. The patient was a 63-yearold man who complained of abdominal pain, melena, and dyspnea on 24 November 2010. We diagnosed stage IV gastric cancer complicated by disseminated intravascular coagulation. Gastric tumor bleeding was not controlled after procedures were repeated three times using gastrofiberscopy. With the patient's consent, we selected the 5-fluorouracil and oxaliplatin combination chemotherapy for treatment. After one cycle of 5-fluorouracil and oxaliplatin therapy, symptoms of bleeding improved and the disseminated intravascular coagulation process was successfully controlled. The primary tumor and multiple metastatic bone lesions were remarkably shrunken and metabolically remitted after eight cycles of chemotherapy. In spite of progression, systemic chemotherapy is effective in disease control; further, the patient gained the longest survival time among cases of gastric cancer with disseminated intravascular coagulation.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.502-509
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• 2005

Sexual reproduction plays an important role in the biology and epidemiology of oomycete plant pathogens such as the heterothallic species Phytophthora infestans. Recent worldwide dispersal of A2 mating type strains of P. infestans resulted in increased virulence, gene transfer, and genetic variation, creating new challenges for disease management. To develop a genetic assay for mating type identification in P. infestans, we used the Amplified Fragment Length Polymorphism (AFLP) technique. The primer combination E+AT/M+CTA detected a fragment specific to A1 mating type (Mat-A1) of P. infestans. This fragment was cloned and sequenced, and a pair of primers (INF-1, INF-2) were designed and used to differentiate P. infestans Mat-A1 from Mat-A2 strains. The Mat A1-specific fragment was detected using Southern blot analysis of PCR products amplified with primers INF-1 and INF-2 from genomic DNA of 14 P. infestans Mat-A1 strains, but not 13 P. infestans Mat-A2 strains or 8 other isolates representing several Phytophthora spp. Southern blot analysis of genomic DNAs of P. infestans isolates revealed a 1.6 kb restriction enzyme (EcoRI, BamHI, AvaI)-fragment only in Mat-A1 strains. The A1 mating type-specific primers amplified a unique band under stringent annealing temperatures of $63^{\circ}C-64^{\circ}C$, suggesting that this PCR assay could be developed into a useful method for mating type determination of P. infestans in field material.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.2
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• pp.129-138
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• 2013

Objectives : This study investigated the relationship between straight leg raising(SLR), valsalva test and size, position of lumbar disc herniation. Methods : We took SLR and valsalva test on 105 patients with lumbar disc herniation. According to the result of MRI findings, this study classified three groups of 105 patients with lumbar disc herniation, bulging, protrusion and extrusion. According to the position of lumbar disc herniation, 72 patients that were diagnosed protrusion and extrsuion were sorted 4 groups, lateral, lateral postero-lateral, central postero-lateral, central. The association size, position of lumbar disc herniation and SLR, valsalva test were analysed. Results : The bigger size of disc herniation, the more positive result of SLR and valsalva test, the lower angle of SLR test. There was not significant association between the position of lumbar disc herniation and the angle of SLR test. Conclusions : The SLR and valsalva test is an useful physical examination to speculate about the degree of lumbar disc herniation.

• Journal of Gastric Cancer
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• v.17 no.2
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• pp.173-179
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• 2017

Purpose: To report our experience of endoscopic botulinum toxin injection in patients who experienced severe delayed gastric emptying after pylorus-preserving gastrectomy (PPG). Materials and Methods: We reviewed the medical records of 6 patients who received the botulinum toxin injection. They presented with severe delayed gastric emptying in the early postoperative period. Endoscopic botulinum toxin was administered as 4 injections of 25-50 IU into each of the 4 quadrants of the prepyloric area. Results: All botulinum toxin injections were successful without any complications, enabling 5 patients to tolerate soft solid diets and one to tolerate a soft fluid diet within 10 days. The endoscopic criteria of 4 patients improved. Symptom recurrence caused 2 patients to undergo repeat injections that were successful. The median follow-up period was 27 months, and all patients could ingest normal regular diets at the last follow-up. Conclusions: Endoscopic botulinum toxin injection is a feasible treatment option for early delayed gastric emptying after PPG.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.1
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• pp.23-32
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• 2015

Facile immobilization of growth factors in hyaluronic acid (HA) hydrogels using dual enzymes is reported in the paper. The hydrogels were formed by using horseradish peroxidase (HRP) and hydrogen peroxide ($H_2O_2$) and transforming growth factor-${\beta}3$ (TGF-${\beta}3$) was covalently conjugated on the hydrogels in situ using tyrosinase (Ty) without any modifications. For the preparation of hydrogels, HA was grafted with poly(ethylene glycol) (PEG), which was modified with a tyrosine. The gelation times of the HA hydrogels were ranging from 415 to 17 s and the storage moduli was dependent on the concentration of $H_2O_2$ and Ty (470-1600 Pa). A native TGF-${\beta}3$ (200 ng/mL) was readily encapsulated in the HA hydrogels and 17% of the TGF-${\beta}3$ was released over 1 month at the Ty concentration of 0.5 KU/mL, while the release was faster when 0.3 KU/mL of Ty was used for the encapsulation (27%). It can be suggested that the growth factors resident in the hydrogels for a long period of time may lead cells proliferating and differentiating, whereas the growth factors that are initially released from the hydrogels can induce the ingrowth of cells into the matrices. Therefore, the dual enzymatic methods as facile gel forming and loading of various native growth factors or therapeutic proteins could be highly promising for tissue regenerative medicines.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.673-676
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• 2005

In this paper, we propose a improved control performance for autonomous mobile robot using the embeded system. The proposed PID(PPID) control method removes steady state error, and has good performance in transient response. The integral term in the proposed method accumulates error in increment section, inverses errors in decrement section, and increases the effect of integral coefficient around target. Therefore, the PPID control method decreases the overshoot, and makes settling time faster than general PID(GPID) control method. In order to verify the effectiveness of the proposed method(PPID), we simulated the position control of DC motor, and experimented the velocity control of autonomous mobile robot. The PPID control method demonstrated good control performance that decrease overshoot and settling time in simulation and experiments.