• Electronics and Telecommunications Trends
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• v.30 no.1
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• pp.42-50
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• 2015

PON(Passive Optical Network)은 설치 및 유지보수가 편리하여 광가입자망으로 널리 사용되고 있다. 대표적인 PON 기술로 IEEE에서 표준화된 EPON(Ethernet PON), 10G EPON과 ITU-T에서 표준화된 GPON(Gigabit capable PON), XG-PON 기술이 있다. EPON 및 GPON은 각각 1G급 및 2.5G급 전송속도를 제공하며 한국, 일본, 중국 등 아시아와 북미 등에서 가입자 서비스 및 비즈니스 서비스용으로 사용되고 있다. 2010년대부터 10G급 PON 기술 사용이 증가되고 있으며, 앞으로 가파르게 증가하고 있는 가입자 트래픽량에 대처하기 위해 40G급 또는 100G급 PON 기술이 사용될 것으로 예상된다. 본고에서는 현재 ITU-T에서 표준화가 진행 중인 NG-PON2(Next Generation PON2) 기술 중 주요기술인 TWDM-PON(Time and Wavelength Division Multiplexing-PON) 기술에 대한 국제 표준화 현황 및 국내외 기술개발 현황을 살펴보고자 한다.

• Korean Journal of Optics and Photonics
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• v.23 no.6
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• pp.264-268
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• 2012

In this paper, we propose a new method for broadcasting in a WDM-PON system which has the merits of a simple and cost effective structure. It can be constructed using only an ASE (Amplified Spontaneous Emission) light source and a PI-RSOA (Polarization Independent - Reflective Semiconductor Optical Amplifier). Error-free broadcast signal transmission over 30 Km for 24 channels at 1.25 Gb/s has been successfully demonstrated.

• Korean Journal of Optics and Photonics
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• v.30 no.6
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• pp.230-236
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• 2019

We propose and demonstrate a searching and autoalignment method for indoor optical wireless communication, using a cost-effective retroreflective sheet and a microelectromechanical system (MEMS) mirror. We use an extremum-seeking method for a single axis and beam steering with a MEMS mirror to maintain a line of sight (LOS) with the optical link. This autoalignment method shows a receiver sensitivity of -31.87 dBm for a bit rate of 2.5 Gb/s over a 7 m communication link.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.1A
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• pp.1-9
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• 2005

We have studied the dispersion properties of a 40 channel x 10 Gbit/s wavelength division multiplexer(WDM) transmission link using standard single mode fiber with all EDFA amplification over 30 x 100 km spans. The dispersion map of the link was investigated by adding fiber sections with positive or negative dispersion at the transmitter, within each amplifier span, and at the receiver. Optimum combinations of these dispersive fiber lengths were attained to significantly enhance the overall transmission performance.

• The Journal of Korean Medicine
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• v.45 no.1
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• pp.139-149
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• 2024

Objectives: The aim of the study was to investigate the potential of Yangdorak diagnosis application against gallstone scanned by Ultrasound diagnosis. Method: For this aim, among 97 patients who had visited Julip Korean Medicine Clinic from July 2016 to June 2023, 30 patients with no gallstone as a control group and 67 patients with gallstone and diagnosed by ultrasonography, were subjected to Yangdorak diagnosis. Then, the changes in Gallbladder Meridian (GB) value as F5 AVE(average of left and right GB value) by Yangdorak were comparatively analyzed between gallstone and non-gallstone groups and statistical significance was evaluated by Tukey's multiple comparison test using Prism software. Results: After all subjects were evaluated by the Yangdorak and ultrasonography to assess the potential of the Yangdorak diagnosis for gallstone, it was noteworthy that the Yangdorak values relevant to F5 AVE of female gallstone group(N=36) were significantly (p<0.001) decreased compared to the control group (N=30), while there was no significance in male gallstone group(N=31). Also, it was recognized significant difference between male and female groups. Conclusion: Based on these results, if the Yangdorak value can be estimated from a decrease with clinical symptom in female patient, it is recommended to follow up the ultrasonography test for diagnosing the gallstone.

• Korean Journal of Acupuncture
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• v.22 no.2
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• pp.1-8
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• 2005

Objective: To inform of the 4th WHO informal consultation meeting on the development of international standard acupuncture points locations, held in Daejeon, Korea, on April $23{\sim}26$, 2005. Results and Conclusions: 12 experts from Korea, China and Japan discussed the locations of 18 controversial points that were not agreed at the previous meeting, and 16 non-controversial points that all 3 nations agreed on the locations but still needed more discussion for their expressions, as well as other non-controversial points that were agreed on both the locations and the expressions but were suggested by Chinese party to be discussed again. Also, the guidelines for English translation of the standard acupuncture points locations and the development of the standard acupuncture points charts, diagrams, and dolls were discussed in this meeting. Through this meeting the locations of ST30, SP11, SP12, TE18, GB9, GB10, LR4, LR5, LR6, BL6, BL7, BL9, GB19 were agreed, but it was suggested that more research would be needed for the locations of LI20, GV26, PC8, PC9, LR7, GB30, LR12, and the expressions of ST36, ST38, ST39, BL1. Due to the time limitation, 16 acupuncture points out of those Chinese party suggested to have more discussion about were not discussed at this meeting and remained to be discussed at the next meeting.

• Journal of Korean Medicine for Obesity Research
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• v.20 no.1
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• pp.20-30
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• 2020

Objectives: The purpose of this study is to verify the effects of H Gambitang (GB-001) on body composition and basal metabolic rate in pre- and post-menopausal obese woman retrospectively. Methods: The study was conducted on 57 middle-aged obese women. They were divided into two groups; pre-menopausal obesity group (Pr-MOG; n=34) and post-menopausal obesity group (Po-MOG; amenorrhea was continued to 14~48 month, n=23) with no significant difference of age, height, body weight and body mass index. All subjects took herbal medicine 3 times a day, for 6 weeks during treatment period. The weight, height, body fat mass, skeletal muscle mass, and basal metabolic rate of all subjects were measured on first visit. The following measurements were repeated after 2 weeks (2nd), 4 weeks (3rd) and 6 weeks (4th) with Inbody 370 (Biospace) equipment to identify changes of body fat mass, skeletal muscle mass, and basal metabolic rate. Results are represented as mean and standard deviation. Results: Po-MOG showed significantly lower decrease rate in weight reduction on 2~6 weeks while significantly higher decrease rate in skeletal muscle reduction on 4~6 weeks. There were no significant differences between two groups in body fat reduction rate and basal metabolic increasing rate. Conclusions: H Gambitang (GB-001) can be used not only in Pr-MOG but in Po-MOG in weight loss although the effect can be lower in Po-MOG. To prevent skeletal muscle mass loss in Po-MOG, following study on adjusting dose and components of H Gambitang (GB-001) thought to be necessary.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.1
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• pp.30-38
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• 2015

Purpose: The aims of our study were to evaluate the blood urea nitrogen to creatinine ratio (BUN/Cr ratio) for distinguishing between an upper and lower gastrointestinal bleeding (GIB), and differentiating between the two most common causes of upper gastrointestinal bleeding (UGIB) presenting with melena in children. Methods: Retrospective data of patients with GIB presenting with melena were analyzed. The data from 60 cases were reviewed including demographics, laboratory findings, diagnostic modalities and results, treatments, and transfusions. Results: Among the 60 cases, UGIB and lower gastrointestinal bleeding (LGIB) were found in 35 cases (58.3%) and 14 cases (23.3%), respectively. The two common causes of UGIB were varices (37.1%), and peptic ulcer diseases (PUD) (31.4%). The BUN/Cr ratio of 30 or greater was higher in UGIB than LGIB (odds ratio [OR], 6.9; 95% confidence interval [95% CI], 1.3-37.2). In UGIB, the BUN/Cr ratio of the varices group was higher than that of the PUD group (p=0.015). The OR for the BUN/Cr ratio appeared as 1.2 per unit increase in the varices group than the PUD group (95% CI, 1.03-1.3). There was no difference between the PUD group and Meckel's diverticulum group. Conclusion: The BUN/Cr ratio was not uneven in differentiating UGIB from LGIB of children with melena in our study. This suggests that BUN/Cr ratio should be interpreted carefully.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.1
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• pp.150-167
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• 2008

Purpose: This is a following study of preceding study about application and improvement of acupuncture benefits in OB & GY disease that was performed in 2007. And this study was performed to complement and compare with a preceding study. Methods: The questionnaire used in preceding survey was distributed to general korean medical doctors who have mainly worked in oriental medical clinic. And results of this survey was compared with results of preceding survey. Results: Results of two surveys were almost similar. 1. The common suitable the sick and wounded name of Ob & Gy disease thought be added in Intra-abdominal acupuncture(腹腔內; CV13 ${\cdot}$ CV16 ${\cdot}$ CV10) in two surveys were dysmenorrhea(K05). infertility(K15), JingHa(pelvic tumor) (K11). In Puncture each adjoining acu-points in one insertion(透刺; SP6-GB39)were dysmenorrhea(K05), climacteric syndrome(K04). amenorrhea (K03), In Puncture each adjoining acu-points in one insertion(透刺; PC6-TE5) were climacteric syndrome(K04), hyperemesis(K16.0), dysmenorrhea(K05). 2. The common acupuncture benefits items that postpartum pain syndrome(K29) should be added as suitable the sick and wounded name were Intra-articular acupuncture(關節內; LI15, SI10, GB30), Intervertebral acupuncture (脊椎間; GV14, 16, 6, 4, 12, 11, 9, 8, 3), Puncture each adjoining acu-points in one insertion (透刺; SP6-GB39). Conclusion: Based on this study, Survey to more KMDs should be performed. And the academic and clinical verifications that supports this results should be supplied.

• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.352-357
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• 1993

The purpose of the present study was to evaluate and compare the periodontal conditions of distally extending cantilever bridges(CB) and removable patial dentures(RPD). 78 patients treated with removable partial dentures were divided into 2 groups; bilateral free-ending (type 1) and unilateral free-ending(type 2). 43 patients treated with distally extending cantilever bridges were divided into 4 groups according to position of missing molars and number of including abutment tooth (or teeth) (type 1-4). Prosthodontic status of the abutment teeth were assessed; overcontoured crown, overhanged margin, embrasure closure, and others. Their Periodonted status were assessed with Plaque Index Gingial Index(GI) Sulcus bleedy Index (SBI), Tooth mobility(TM) & Posher depth(PPD). 35.9% of RPD group and 38.1 of CB grouphad disconfort on mastication with prosthetics. 16.7% of RPD group and 6.1% of CB group showed on opposing sites. Overhanged margins were 58.3% for RPD group and 86.6% for GB group. 45.5% of RPD group and 72% of CB group had embrasure closure on the abutment teeth. 30.5% of GB group had oversized pontic. Gb group showed much higher clinical parameters than RPD groups, but statistically not significant. Type 2 of RPD group showed lower GI and SBI, but statistically not significant. Type 3 of CB group showed the highest GI and SBI and type 2 showed the highest tooth mobility, but there is no differences between the same type of groups. In conclusion, only minor differences in periodontal conditions were recorded in RPD and CB group.