스테레오 카메라의 거리오차 보정을 위한 새로운 화소간격 파라미터 교정기법

金棕晩,金炯奭,金聖中 全北大學校 1996 論文集 Vol.42 No.-

In this paper, new calibration technique of the maladjusted stereo cameras using calibrated pixel distance parameter is proposed. The camera calibration in stereo vision systems is a necessary procedure for correct depth computation. Intra and extra parameters should be obtain to determine the relation between image and 3-dimensional world coordination through calibration experiment. One difficulty is in camera alignment for parallel installation: placing two CCD arrays in a plane. No effective methods for such alignment have been proposed till now. Some amount of depth error caused from such non-parallel installation of cameras is inevitable. If the pixel distance parameter which is one of intra parameter is calibrated with known points, such error can be compensated in some amount. Such error compensation effects with calibration technique of the calibrated pixel distance parameter are demonstrated with some experiments and as a results, the effects of the proposed method that used compensated parameters is three times better than that of uncompensed parameter methods.

다차원 입력 공간에 적합한 신경회로망 학습과 로보트 제어에 이용

金炯奭,金聖中 全北大學校 1993 論文集 Vol.35 No.-

Collision avoidance in robot control requires a lot of programming effort. A new collision free control scheme using neural networks is proposed to ease such problem. After learning dangerous and safe regions of collision, distance information among robots can be extracted from outputs of a neural network. Then, the information is converted to repulsive force for each joint. Neural network with many input variables has a problem of requiring a large set of training patterns. A pattern reduction technique which selects only essential patterns for learning is used. Also, a learning scheme with dynamic learning rate in which individual pattern is emphasized depending on the difficulty of learning is proposed. Two planar robots with two joints are used to simulate the learning and collision avoidance control. Simulation results are satisfactory.

VP-16으로 성공적으로 치료된 위 Kaposi 육종 1예

양웅석,송근암,조몽,이재승,송철수,김형욱,김영민,이수봉,김태오,이성훈 대한소화기내시경학회 1999 Clinical Endoscopy Vol.19 No.4

The skin is an uncommon site of distant metastasis from any internal malignancy, and the incidence of metastatic skin lesions as the first symptom of disease is only 0.8% in patients with all systemic malignancies. Furthermore, cutaneous metastasis from adenocarcinoma of the stomach has been found to be extremely rare. A 35-year-old female patient was admitted due to multiple cutaneous nodules in her chest, abdomen, and back. A gastroendoscopic examination and biopsy was made according to the results of skin pathologic findings. Stomach and skin biopsy results revealed a signet ring cell type of adenocarcinoma. A case of gastric adenocarcinoma in which metastatic skin nodules appeared as the first sign of disease, is here in reported with a review of related literature.

자율분산 신경망을 이용한 지형정보 압축저장

崔鍾洙,金棕晩,金炯奭,金聖中 全北大學校 1994 論文集 Vol.38 No.-

A new neural network structure called Self-Organized Distributed Networks (SODN) is proposed for developing the neural network-based multi-dimensional system models. The learning with the proposed networks is fast and precise. Such properties are caused from the local learning mechanism. The SODN is a hybrid structure of a learning network and a distribution network. The learning network is composed of a set of subnetworks while the distribution network composed of a set of self-organized units. With this structure, the SODN provides a better interpolation than the conventional locally distributed networks (especially RBF networks). In this paper, comparisons with multilayer neural network and RBF networks have been done through learning of two dimensional terrain elevation data.

일부 조선업 근로자의 직업성 요통 발생실태 및 위험요인에 관한 연구

고상백,김형식,최홍렬,김지희,송인혁,박준한,박종구,장세진,차봉석 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목적 : 이 연구에서는 한 사업장의 동일한 코호트내에서 직업성 요통의 발생 및 발생원인에 대해 조사하고자 하였다. 방법 : 연구대상은 1995년 12월 현재 한 조선업체에 종사하는 근로자 중에서 1995년 12월 31일 까지 요통이 이미 발생한 근로자와 1995년 당시 검진 미수검자를 제외한 9,784명을 연구대상으로 하였다. 요통 발생군은 1996년부터 1998년까지 3년간 추적 관찰하여 요통으로 4일 이상 통원 또는 입원치료를 받은 근로자로 하였다. 발생률은 요통발생 당시 연도를 기준으로 하여 해당 연도의 4일 이상 신규치료를 받은 중등도 이상의 요통근로자를 분자로 하였고, 해당년도 사업장의 종사하는 근로자 총수(과거 요통자 제외)를 분모로 간주하였다. 요통 발생군은 외상성 요통과 직업관련성 요통으로 대별하였으며, 위험요인과 질병 발생간의 관련성을 보기 위한 Cox모형에서 그 위험도를 파악하고자 할 때에는 직업성 요통만을 환자군으로 선정하였다. 결과 및 결론 . 요통 발생률은 근로자 천명당 1998년 3.1명, 1997년 8.8명, 1996년 7.8명이었다. 요통점유율의 범위는 10.99∼25.66이었다. 연령별 요통 발생률은 30대, 40대에서 높은 발생률을 보였다. 진단명에 따른 발생률은 추간판 탈출증, 염좌, 척추골절, 척추분리증, 척추협착증 순이었다 직업성 요통 발생자들의 직업적 요인을 알아보기 위하여 요통 발생 당시 작업형태를 알아본 결과, 물건을 들다가 66명(35.3%)이 발생하여 가장 큰 빈도를 차지하였고, 물건을 옮기는 과정에서 19명(10.2%)이 발생하여 2위를 차지하였고, 넘어지거나(8.6%), 물건을 당기는 자세(8.0%), 값자기 일어서다(7.5%) 순으로 요통이 발생하였다. 직업성 요통에 영향을 주는 일반적 특성 및 직업적 특성에 판한 상대위험도 및 95% 신뢰구간를 구한 결과, 요통발생에 영향을 주는 유의한 변수로는 체질량 지수(비만도), 교대여부, 중량물 취급여부였다. Objectives : This study was conducted to estimate the incidence rate, and to identify the risk factors for the occupational low back pain among shipyard workers. Methods : The study subjects consisted of 9,784 workers who were employed in a ship-building industry (excluded workers who had a history of low pack pain before 1995 or did not take periodic health examination in 1995) . The cases were 220 people who experienced back pain from January 1, 1996 to December 31, 1998. To assess risk factors for occupational low back pain, Cox propotional hazard model was used. Results : During the recent three years from 1996 to 1998, the incidence rate per 1,000 persons was 7.8 in 1996, 8.8 in 1997, and 3.1 in 1998. The main causes of work-related low back pawn were sprain, strain and disc herniation. Lifting was the most common cause of back pain (35.3%) , and carrying (10.2%) and pulling (8.0%) were followed. In Cox proportional harzard model, independent risk factors for back pain were body mass index(R.R. ; 1.54, 95% C.1. : 1.06-2.25), shift work(R.R. ; 1.65, 95% C.1. : 1.19-2.28), and lifting heavy material(R. R., 3.95, 95% C.1. : 2.29-6.82). Conclusions . This study suggests that the risk factors of back pawn In shipyard work-ers were body mass index, shift work and lifting.

동적계획법과 적응 비용 변환을 이용한 영상 모자이크의 seam-line 결정

전재춘,서용철,김형석 한국지리정보학회 2004 한국지리정보학회지 Vol.7 No.2

영상 모자이크 작업에서 두 영상 간의 경계선이 보이지 않는 최적의 seam-line을 구하기 위해 화소값 차이 변환과 동적계획법 이용 알고리즘을 제안하였다. 영상 간의 경계선은 두 영상의 화소값 차이가 적은 화소를 따라 형성되는 것이 시각적 부담이 적다. 이 화소들을 연결하는 것은 최적경로를 찾는 알고리즘을 이용할 수 있다. 최적 경로 결정에 효과적인 동적계획법을 seam-line 결정에 직접 적용하면 화소값의 차이뿐만 아니라, seam-line의 길이에 따라 영향을 받는 거리영향문제가 발생한다. 이 논문에서는 적응적 변환함수를 사용하여 비용 변환을 수행하고, 변환된 비용공간 상에서 동적계획법을 적용하여 거리영향이 억제된 최적 seam-line을 구할 수 있는 알고리즘을 개발하였다. 또한 결정된 seam-line을 평가하기 위해 일정한 개수의 상위 화소값의 차이를 누적한 값(SFBPD)을 척도로 제시하였다. 제안한 seam-line 결정방법을 다양한 종류의 영상에 대해 적용 실험하였으며, 시각적 및 SBPD 값에 의한 수치적 결과를 제시하였다. A seam-line determination algorithm is proposed to determine image border-line in mosaicing using the transformation of gray value differences and dynamic programming. Since visually good border-line is the one along which pixel differences are as small as possible, it can be determined in association with an optimal path finding algorithm. A well-known effective optimal path finding algorithm is the Dynamic Programming (DP) . Direct application of the dynamic programming to the seam-line determination causes the distance effect, in which seam-line is affected by its length as well as the gray value difference. In this paper, an adaptive cost transform algorithm with which the distance effect is suppressed is proposed in order to utilize the dynamic programming on the transformed pixel difference space. Also, a figure of merit which is the summation of fixed number of the biggest pixel difference on the seam-line (SFBPD) is suggested as an evaluation measure of seamlines. The performance of the proposed algorithm has been tested in both quantitively and visually on various kinds of images.

Lateral Information-Propagation Neural Networks for on-line Interpolation through Inter-node Information Propagation

Hyong-Suk Kim,Jong-Man Kim 한국정보과학회 1998 Journal of Electrical Engineering and Information Vol.3 No.4

Lateral Information-Propagation Neural Networks (LIPN) is proposed for fast interpolation through inter-node information propagation. If information is not available for every state, that for other states can be generated with some interpolation technique utilizing neighbored information. The proposed interpolation is a neural network-based method. Each node of the neural network represents a state in the quantized input space. A node of the network is composed of a processing unit and fixed weights from its adjacent nodes as well as its input terminal. With such neural network structure, information of a node propagates among neighbor nodes laterally and inter-node interpolation is achieved. The interpolation principle of the LIPN is explained through some numerical method in this paper. Also, 1-D LIPN hardware has been implemented with general purpose analog ICs to test the interpolation capability of the proposed neural networks. Experiments with static and dynamic signals have been done upon the LIPN hardware.

특발성 대장직장정맥류 1 예

김현재,정인식,김형준,김성수,이강문,김명철,최황,선희식,이창돈,한석원,채현석,방춘상,강형주,이관형,김세희,최규용 대한소화기내시경학회 2001 Clinical Endoscopy Vol.23 No.6

The effect of the bone marrow aspirate concentrate on arthroscopic rotator cuff repair

Hyong Suk Kim,Tae Yon Rhie,Ki Woong Lee,In Woong Park 대한견주관절의학회 2021 대한견주관절학회 학술대회논문집 Vol.2021 No.3

Introduction and Background A significant percentage rotator cuff tears failed to completely heal after repair surgery. Several attempts were done using biologic augmentation to achieve better integrity at the tendon-to-bone junction for enhancing the healing of rotator cuff repairs. The purpose of this study was to evaluate the effect of bone marrow aspirate concentrate (BMAC) on the result of the arthroscopic rotator cuff repair. The hypothesis was that the arthroscopic rotator cuff repair completed by the bone marrow aspirate concentrate would enhance the healing rate after surgery. Material and Method From February 2 September 2018, patients with >2.5 cm in size of rotator cuff tears who underwent arthroscopic rotator cuff repair were included in this study. The patients who underwent arthroscopic rotator cuff repair alone were classified as group I and the patients who underwent arthroscopic rotator cuff repair complemented by injection of BMAC were classified as group 2. Postoperative clinical outcomes were evaluated pain visual analog scale (VAS), American Shoulder and Elbow Surgeons ASES) score, simple shoulder test(SST) score at 6, 12 months after surgery and every annual follow ups. Anatomical outcomes were evaluated by using MRI at 12 months after surgery. A comparison of the clinical and anatomical outcomes were made between the groups retrospectively. Results The number of cases were 81 (group 1) and 90 (group 2) and the average age was 64.3 years and 67.5 years respectively. (p>0.05) Mean follow up period was 22.3 (group 1), 20.4 (group 2) months, respectively. Preoperative sizes of tear were retraction 2.8cm in group 1 and retraction 2.9cm in group 2 (p>0.05). At final follow up, compared to preoperative state, Pain VAS, ASES score and SST score improved from 7.3 to 0.9, from 21.3 to 93.3 and from 1.5 to 10.3, respectively in Group 1 (all P<0.05), and improved from 7.9 to 1.3, from 15.2 to 91.7 and from 1.5 to 11.1, respectively in Group 2 (all P<0.05). Range of motion and functional scores were not significantly different between the two groups (P > .05). Healing failure rates were 34.6% (28/81) in group 1 and 21.1% (19/90) in group 2 (P=0.04). Conclusions Direct injection of bone marrow aspirate concentrate (BMAC) to the repaired cuff tendon can be a treatment option that significantly enhances the tendon-to-bone healing after arthroscopic rotator cuff repair for patients with rotator cuff tears >2.5cm.

Lateral Information-Propagation Neural Networks for on-line Interpolation through Inter-node Information Propagation

Hyong-Suk Kim,Jong-Man Kim 대한전기학회 1998 Journal of Electical Engineering and information S Vol.3 No.4