• Environmental Mutagens and Carcinogens
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• v.8 no.1
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• pp.47-55
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• 1988

발생중인 계배의 날개형성에 미치는 retinoic acid(RA)의 효과를 알아보았다. RA처리는 날개원기의 전단부로 부처 거울상을 띤 지골의 복제를 유발하였다. 이러한 RA처리에 따른 지골의 복제 효과는 발생시기 및 처리량에 의존적이었다. 즉 stage 18시기의 날개원기에 RA를 처리했을 때 최대의 지골 복제 효과가 유발되었으며, 20mg/ml 의 RA 용액으로 처리했을 때 최대의 지골 복제 효과가 나타났다. 이러한 실험결과는 RA 처리가 날개원기 세포의 positional value를 전후축 상에서 후위화하기 때문에 나타나는 것으로 해석될 수 있으며, 후위화의 정도는 발생단계 및 처리량에 의존적임을 시사하고 있다.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.1122-1126
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• 1991

As microcomputers have become widespread and the high speed solenoid valves have been developed, digitally controlled hydraulic systems are used in many applications. This study deals with position control of hydraulic cylinder operated by two port 3-way high speed solenoid valve using a self-learning strategy. This was done by developing a control algorithm for the microcomputer which always automatically adjust the length of control pulse to the optimum value in accordance with the error regardless of changes in the operating condition and physical differences between components. Tests carried out in the laboratory indicate that a positional accuracy could be improved.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.1
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• pp.91-98
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• 1991

This study was made to analyze the positional relationship of mandible to hinge axis in normal subject as the diagnostic criteria of T.M.J. dysfunction. The author has conducted the study using the Cephalometric P-A view, and dental of 53 males and 51 females. By measurement, the standard value of cranio-facial and occlusal asymmetry in normal subject obtained. The following results were obtained: 1. Although the degree of the difference between right and left width in each measured line was small, asymmetry in normal subject could be identified. 2. In male, measurement between genial tubercle and hinge axis is 127.20±6.06㎜ in left, 125.83±6.25㎜ in right, and angle between genial tubercle and hinge axis is 48.48±3.53° in left, 49.58±3.72° in right. In female, measurement is 119.32±5.81㎜ in left, 118.82±5.35㎜ in right and angle is 48.06±2.15° in left, 48.17±2.31° in left, 48.17±2.31° in right. 3. In male, difference between left and right canine cusp tip of maxilla about X-bar is 0.70±0.59㎜, and that of central pit of first molar of maxilla is 0.98±0.75㎜. In female, difference is 0.64±0.52㎜ in canine and 0.92±0.76㎜ in molar.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.74-82
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• 2002

In Intensity Modulated Radiotherapy (IMRT), radiation is delivered in a multiple of Multileaf Collimator (MLC) subfields. A subfield with a small leaf-to-leaf opening is highly sensitive to a leaf-positional error. We introduce a method of identifying and rejecting IMRT plans that are highly sensitive to a systematic MLC gap error (sensitivity to possible random leaf-positional errors is not addressed here). There are two sources of a systematic MLC gap error: Centerline Mechanical Offset (CMO) and, in the case of a rounded end MLC, Radiation Field Offset (RFO). In IMRT planning system, using an incorrect value of RFO introduces a systematic error ΔRFO that results in all leaf-to-leaf gaps that are either too large or too small by (2ㆍΔRFO), whereas assuming that CMO is zero introduces systematic error ΔCMO that results in all gaps that are too large by ΔCMO = CMO. We introduce a concept of the Average Leaf Pair Opening (ALPO) that can be calculated from a dynamic MLC delivery file. We derive an analytic formula for a fractional average fluence error resulting from a systematic gap error of Δ$\chi$ and show that it is inversely proportional to ALPO; explicitly it is equal to, (equation omitted) in which $\varepsilon$ is generally of the order of 1 mm and Δx=2ㆍΔRFO+CMO. This analytic relationship is verified with independent numerical calculations.

• Journal of Oral Medicine and Pain
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• v.19 no.2
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• pp.193-203
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• 1994

The author performed this study for investigation of the magnitude of mandibular positional change caused by joint sound during mandibular opening and closing movement. There have been many studies stated mandibular border movement or other functional movement, and there also have been many studies reported clicking sound related to mandibular movement speed, trajectory and clinicl course of temporomandibular disorders(TMDs), but there have not been so many studies stated spatial mandibular position accompanied by joint sound. For this study 46 TM joint from the patients with TMDs were used and they were compared by character and occuring phase of the joint sound. Synchronized data which were amplitude and frequency of joint sound and amount of mandibular positional change were collected through sonopak and BioEGN rotate of Biopak system, respectively. Mandibular position was analyzed for translational and rotational movement change between before and after joint sound. The obtained data were processed with SAS program and summary of this paper were as follows : 1. Mean value of the amount of translational movement in whole joints were 6.0mm in vertical direction, 3.3mm in anteroposterior direction and 0.8mm in lateral direction between before and after joint sound. 2. Mean value of the amount of translational movement in clicking joinnts showed slightly increased tendency than in popping joints. 3. The amount of mandibular change in translational movement during closing phase were more than during opening phase. 4. The amount of mandibular rotational change in whole joints were $1.1^{\circ}$, 1.0mm in frontal plane and $0.9^{\circ}$, and 0.8mm in horizontal plane. 5. The amount of rotational movement were more in clicking joints than in popping joints and were more during closing phase than during opening phase, but statistically significance were showed only in frontal plane.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.5
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• pp.316-323
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• 2009

Purpose: This study was performed to evaluate three-dimensional positional change of the condyle using 3D CT after bilateral sagittal split ramus osteotomy (BSSRO) in skeletal class III patients. Patients and methods: Nine patients who underwent BSSRO for mandibular set-back in skeletal class III malocclusion without facial asymmetry were examined. Miniplates were used for the fixation after BSSRO. 3-D CT was taken before, immediately after, and 6 months after undergoing BSSRO. After creating 3D-CT images using V-works $4.0^{TM}$ program, axial plane, coronal plane, & sagittal plane were configured. Three dimensional positional change, from each plane to the condyle, of the nine patients was measured before, immediately after, and 6 months after undergoing BSSRO. Results: 1. The mean value of mandibular set-back for nine mandibular prognathism patients was 7.36 mm (${\pm}\;2.42\;mm$). 2. In the axial view, condyle is rotated inward immediately after BSSRO (p < 0.05), comparing with preoperative but outward 6 months after BSSRO comparing with postoperative (p < 0.05). 3. In the axial view, condyle is moved laterally immediately after BSSRO (p < 0.05), comparing with preoperative but regressed 6 months after BSSRO comparing with preoperative (p > 0.05). 4. In the frontal & coronal view, there is changed immediately after and 6 months after BSSRO, comparing with preoperative but no statistical difference. Conclusion: These results indicate that three-dimensional positional change of the condyle in skeletal class III patients is observed lateral displacement & inward rotation immediate after BSSRO, but the condyle in 6 months after BSSRO tends to regress to preoperative position.

• Korean journal of communication and information
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• v.33
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• pp.53-86
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• 2006

This paper presents comparative analysis of the traits of personal network structure shaping in local press organizations of Korea. For this analysis, this study attempts to investigate three topics. First, the density traits of personal network structure in the whole of local press organization. Second, the comparison of density trait shaping in personal network structure between press section of local broadcasting stations and local newspaper companies. Third, the positional trait in each local press organization. To answer the questions, the data concerning commissioners and executive members in local daily newspapers and local broadcasting organizations from the Civic Government to the People's Government have been collected and analyzed. The interconnections of regional(birthplace) and educational(university graduated) aspect were analyzed via methods of cross analysis, density analysis and correspondence analysis. In brief, major findings of this study are as follows ; As a result of analyzing cross analysis and density analysis of the personal network based of regional and educational aspect, the numerical value of density was too high on the whole of local press organizations. But, especially local newspaper companies has been showed that was higher density compared with press section of local broadcasting stations. And, positional distance between local press organizations were showed obviously in the case of regional(birthplace) aspect. But, in case of educational aspect, positional distance were showed obviously between commissioners and executive members.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.1
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• pp.95-99
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• 2018

In this paper, we propose an efficient pixel value prediction algorithm that can accurately predict pixel value using neighboring pixel values scanned in reverse s-order in the image. Generally, image has similarity with similar values between adjacent pixel values, and may have directional edge characteristics. In this paper, we proposed a method to improve pixel value prediction accuracy by improving GAP(Gradient Adjacent Pixel) algorithm for predicting pixel value by using similarity between adjacent pixels and edge characteristics. The proposed method increases the accuracy of the predicted pixel value by precisely predicting the pixel value using the positional weights of the neighboring pixels. Experiments on real images confirmed the superiority of the proposed algorithm. The proposed algorithm is useful for applications such as reversible data hiding, reversible watermarking, and data compression applications.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.3
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• pp.315-322
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• 2000

DSM(Digital Surface Model) is a digital model which represents the surface elevation of a region. DSM is necessary for orthoimage generation, and frequently used in man-made object extraction from aerial photographs nowadays. Image matching technique enables automatic DSM generation. This proposed a image matching method which can be applied to automatic generation of DSM for Built-up Area. The matching method proposed is to find conjugate points and conjugate lines from overlapping aerial images. In detecting conjugate points, the positional relation between possible conjugate point pair as well as correlation of pixel gray value is compared. In detecting conjugate lines, the color attribute of flank region of line, shape of line, positional relation between neighborhood points and lines, and the connection relation between lines are compared. The proposed matching method is assumed to be useful for DSM generation including Built-up Area.

• Safety and Health at Work
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• v.13 no.1
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• pp.40-50
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• 2022

Background: Underground mines have several hazards that could lead to serious consequences if they come into effect. Acquiring, evaluating, and using the real-time data from the atmospheric monitoring system and miner's positional information is crucial in deciding the best course of action. Methods: A graphical user interface-based software is developed that uses an AutoCAD-based mine map, real-time atmospheric monitoring system, and miners' positional information to guide on the shortest route to mine exit and other locations within the mine, including the refuge chamber. Several algorithms are implemented to enhance the visualization of the program and guide the miners through the shortest routes. The information relayed by the sensors and communicated by other personnel are collected, evaluated, and used by the program in proposing the best course of action. Results: The program was evaluated using two case studies involving rescue relating to elevated carbon monoxide levels and increased temperature simulating fire scenarios. The program proposed the shortest path from the miner's current location to the exit of the mine, nearest refuge chamber, and the phone location. The real-time sensor information relayed by all the sensors was collected in a comma-separated value file. Conclusion: This program presents an important tool that aggregates information relayed by sensors to propose the best rescue strategy. The visualization capability of the program allows the operator to observe all the information on a screen and monitor the rescue in real time. This program permits the incorporation of additional sensors and algorithms to further customize the tool.