삼각측량 시스템을 이용한 물체의 3-D 정보추출 관한 연구

이호영,김국세,문정환,이철승,방극인,박영옥 조선대학교 전자정보통신연구소 2002 電子情報通信硏究所論文誌 Vol.5 No.2

The 3-D shape use to effect of movie, animation, industrial design, medical treatment service, education, engineering etc... But it is not easy to make 3-D shape from the information of 2-D image. There are two methods in restoring 3-D video image through 2-D image; First the method of using a laser; Second, the method of acquiring 3-D image through stereo vision. Instead of doing two methods with many difficulties, I study the method of simple 3-D image in this research paper. We present here a simple and efficient method, called direct calibration, which does not require any equations at all. The direct calibration procedure builds a lookup table(LUT) linking image and 3-D coordinates by a real 3-D triangulation system. The LUT is built by measuring the image coordinates of a grid of known 3-D points, and recording both image and world coordinates for each point; the depth values of all other visible points are obtained by interpolation.

바이폴라 델타 신호에 대한 GMSK 변조

방승철(Seung-Cheol Bang),이우상(Woo-Sang Lee) 한국통신학회 2013 韓國通信學會論文誌 Vol.38 No.7B

기본적으로 GMSK는 NRZ 펄스열을 가우시안 저역 통과 필터로 전 처리한 후에 GMSK 신호를 생성하지만, 본 논문에서는 델타 펄스열에 대한 GMSK 변조 시스템을 제안하였다. 제시된 시스템은 바이폴라 델타 펄스로 가우시안 펄스를 발생시키는 가우시안 펄스 생성기, +Tb/2와 -Tb/2 사이의 차분기, 그리고 주파수변조 함수를 위한 정합 필터로 구성한다. 기본적인 GMSK 변조와의 비교를 통해 스펙트럼은 40[㏈] 감쇠 대역폭에서 약 35[%] 협소하며, 스펙트럼의 중심은 더 낮고, 제로 크로싱 성질이 있는 것으로 나타났다. In the basic GMSK, the modulated signals are generated by the preprocessing of NRZ pulse trains with the gaussian low pass filter. In this paper, we proposed the GMSK modulation system with the delta pulse trains. The proposed system constructed with the gaussian pulse generator triggered by the bipolar delta pulse, the differentiator between +Tb/2 and -Tb/2, and then a matched filter for frequency-modulation function. The spectrum of proposed system was found to be smaller than about 35[%] at 40[㏈] attenuated bandwidth, and the center spectrum to be lower than the basic GMSK with zero-crossing property.

다중 물체 추적을 위한 이진의 Joint 변환 상관기

방승철(Seung-Cheol Bang),이승현(Seung-Hyun Lee),김우연(Woo-Yeon Kim),윤상로(Sang-Ro Yoon),김은수(Eun-Soo Kim) 대한전자공학회 1991 대한전자공학회 학술대회 Vol.1991 No.6

바이폴라 델타 구동 GMSK에 대한 복조

방승철(Seung-Cheol Bang) 한국통신학회 2013 韓國通信學會論文誌 Vol.25 No.8

델타 구동 GMSK는 바이폴라 델타 신호로 가우시안 펄스를 생성하고 +Tb/2와 -Tb/2 사이의 차분 신호로 위상변조하는 방식이다. 이러한 방식에 대한 복조는 기존의 GMSK와는 다르게 설계해야 한다. 본 논문에서는 인접한 비트 간의 위상 변화를 검출하고 위상 영역을 경판정한 다음에 상태 전이로 이진 데이터를 복원하는 방식을 설계하였다. AWGN 채널에 대한 전산모의실험 결과, 이진 데이터의 런 랭스에 의한 비트 오율의 영향이 확인되었으며, 이론적인 코히어런트 복조의 BER과 비교해서 BTb=0.3에 대하여 2[dB] 정도의 성능 저하가 있는 것으로 분석되었다. The delta driven GMSK is a modulation scheme to generate the gaussian pulse by the bipolar delta signal and to modulate the phase function with the differential gaussian pulse between +Tb/2 and -Tb/2. The demodulation of delta driven GMSK differs from conventional GMSK schemes. This paper proposed a demodulation with the differential phase detector at the end of each bit interval. A designed detector then finds the one of the possible region by hard decision, in which the phase difference lies. Finally the binary data can be recovered by state transition process. Through the BER simulation for AWGN channel, it was found that the proposed demodulation effected by the run length of binary data. The simulated BER degradation of about 2[dB] was analyzed, as compared to the theoretical coherent demodulation with BTb=0.3.

DESIGN OF VARIABLE GEOCASTING BASED ON AD-HOC NETWORK

Cheol-Seung Lee,Kuk-Se Kim,Sun-Kwang Bang,Seong-Soo Ahn,Joon Lee 한국멀티미디어학회 2007 한국멀티미디어학회 국제학술대회 Vol.2007 No.-

Mobile Ad-hoc networks have recently attracted a lot of attention in the research community as well as in industry. Although the previous research mainly focused on several of Ad-hoc in routing, we consider, in this paper, how to efficiently support applications such as variable Goocasting based on Ad-hoc networks. The goal of a geocasting protocol is deliver data packets to a group of nodes that are located within a specified geocasting region. Previous research that support geocast service in mobile computing based on Ad-hoc have the non-optimization problem of data delivery path, overhead by frequent reconstruction of the geocast tree, and service disruption problem. In this paper, we propose the mobility pattern based geocast technique using variable service range according to the mobility of destination node and resource reservation to solve this problem. The experimental results show that our proposed mechanism has improved performance of Accessibility & Network Overhead than previous research.

International Digestive Endoscopy Network consensus on the management of antithrombotic agents in patients undergoing gastrointestinal endoscopy

Seung Joo Kang,Chung Hyun Tae,Chang Seok Bang,Ki-Nam Shim,Cheol Min Shin,Young-Hoon Jeong,Miyoung Choi,Joo Ha Hwang,Yutaka Saito,Philip Wai Yan Chiu,Rungsun Rerknimitr,Christopher Khor,Vu Van Khien,Ke 대한소화기내시경학회 2024 Clinical Endoscopy Vol.57 No.2

Antithrombotic agents, including antiplatelet agents and anticoagulants, are widely used in Korea because of the increasing incidence of cardiocerebrovascular disease and the aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. The clinical practice guidelines for this issue, developed by the Korean Society of Gastrointestinal Endoscopy, were published in 2020. However, new evidence on the use of dual antiplatelet therapy and direct anticoagulant management has emerged, and revised guidelines have been issued in the United States and Europe. Accordingly, the previous guidelines were revised. Cardiologists were part of the group that developed the guideline, and the recommendations went through a consensus-reaching process among international experts. This guideline presents 14 recommendations made based on the Grading of Recommendations, Assessment, Development, and Evaluation methodology and was reviewed by multidisciplinary experts. These guidelines provide useful information that can assist endoscopists in the management of patients receiving antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

나선형의 집전용 CNT 섬유로 구성된 신개념 리튬이온 전지 실의 제작 및 시험

방승환(Seung Hwan Bang),김철(Cheol Kim) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12

Fiber-type flexible lithium ion battery with wound carbon nanotube fibers and active materials were developed and fabricated. Carbon nanotube fiber is used as a current collector because it has high strength and remarkable electrical conductivity. LiMn₂O₄ and Li₄Ti<SUB>5</SUB>O<SUB>12</SUB> are deposited on the surface of carbon nanotube fibers as an active material in cathode and anode, respectively. Tensile strength of the CNT fiber with active material is measured by tensile tests to investigate the mechanical characteristics. Electrochemical property is also measured by a battery tester during charging and discharging processes. The test results showed that the novel battery was applicable to wearable clothes.

저칼륨 주기성 마비를 동반한 원위성 세뇨관 산증

진승원,박철휘,박종현,김선명,신미정,정명선,김형욱,박선숙,안유배,장윤식,방병기 대한내과학회 1997 대한내과학회지 Vol.53 No.3S

저자들은 이전에 저칼륨혈증을 치료받았던 환자에서 갑자기 발생한 전신적인 근 무력감을 토대로 검사한 결과 H^+ -ATPase 분비 장애(secretory defect)에 의한 원위성 세뇨관 산증에 의한 신장을 통한 과량의 칼륨 손실로 인해 생긴 저칼륨 혈증에 의한 주기성마비 1예를 경험하였다. 원위성 세뇨관 산중에 의한 저칼륨 주기성 마비는 국내에 보고된 바가 없기에 문헌 고찰과 더불어 처음으로 보고 하는 바이다. Peridoic muscle paralysis is characterized by acute reversible generalized muscular weakness and absent deep tendon reflexes, usually sparing sensation and consciousness. Although hypokalemia is common in renal tubular acidosis(RTA), acute hypokalemic periodic paralysis(HPP) is extremely rare and not known in Korea. A 27-year--old man admitted due to generalized muscular weakness. We observed a hypokalemia (initial serum postassium=2.2mEg/L), hyperchloremic metabolic acidosis (initial serum pH=7.324 and serum chloride= 111mEg/L), and relative alkaline urine (initial urine pH=6.611) and diagnosed with hypokalemic periodic paralysis by distal renal tubular acidosis suspiciously. In this patient an ammonium chloride (NH4CL, 0.lg/㎏) loading test failed to decrease urine pH below 5.5 when blood pH decreased to 7.229. The furosemide test was done to evaluated a underlying mechanism of distal RTA which the fractional excretion of potassium incrased from 33.5% to 57.5% but urine pH did not significantly changed from 6.30 to 6.21. These results suggested that his distal RTA was probably due to H^+-ATPase secretory defect. In this case, we confirmed hypokalemic periodic paralysis in a young man complicated with distal RTA due to H^+-ATPase pump defect and managed successfully by potassiun and bicarbonate replacement.

수치해석을 통한 충격 시 접시 스프링의 비선형 특성 고찰

방승우(Seung-Woo Bang),이해진(Hae-Jin Lee),권오철(O-Cheol Kwon),이정윤(Jung-Youn Lee),오재응(Jae-Eung Oh) 한국소음진동공학회 2007 한국소음진동공학회 학술대회논문집 Vol.2007 No.11

복막투석 환자에서 발생한 중심성 뇌교 수초용해증 1 예

이승훈,김현재,김형준,유원종,박선미,방병기,최의진,송호철 대한내과학회 2001 대한내과학회지 Vol.61 No.6

Central pontine myelinolysis (CPM) is a rare syndrome, especially in uremic patients undergoing dialysis. CPM induced by diabetic coma in hemodialysis patients or associated with rapid correction of hyponatremia in peritoneal dialysis patients have been reported. However, its pathogenesis has been unclear. We report a case of CPM in a 67-year-old female uremic patient undergoing continuous ambulatory peritoneal dialysis, who was admitted to our hospital for drowsy mentality. Sodium was normal (140 mEq/L) initially and throughout the entire clinical course. The fasting blood sugar level was 110 mg/dL, serum osmolality 312 mOsm/KgH2O and osmolar gap 9.47. The axial T2-weighted brain MRI showed high signal intensity in the basal pons.(Korean J Med 61:660-663, 2001)