• Smart Structures and Systems
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• 제8권1호
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• pp.69-92
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• 2011

This paper presents an emergent pattern recognition approach based on the immune network theory and hierarchical clustering algorithms. The immune network allows its components to change and learn patterns by changing the strength of connections between individual components. The presented immune-network-based approach achieves emergent pattern recognition by dynamically generating an internal image for the input data patterns. The members (feature vectors for each data pattern) of the internal image are produced by an immune network model to form a network of antibody memory cells. To classify antibody memory cells to different data patterns, hierarchical clustering algorithms are used to create an antibody memory cell clustering. In addition, evaluation graphs and L method are used to determine the best number of clusters for the antibody memory cell clustering. The presented immune-network-based emergent pattern recognition (INEPR) algorithm can automatically generate an internal image mapping to the input data patterns without the need of specifying the number of patterns in advance. The INEPR algorithm has been tested using a benchmark civil structure. The test results show that the INEPR algorithm is able to recognize new structural damage patterns.

• 한국측량학회지
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• 제33권5호
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• pp.363-371
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• 2015

개체 추출은 원격탐사 분야의 주된 연구분야 중 하나로, 고해상도 위성영상의 활용도가 높아짐에 따라 보다 세밀하고 특정적인 개체를 추출할 수 있게 되었다. 기존의 화소 기반의 영상 처리 기법들은 고해상도 위성영상의 분광 및 기하학적인 다양성과 복잡성을 제대로 반영하기 어렵기 때문에 근래에는 영상분할 기술을 기반으로 하는 많은 연구가 진행되고 있다. 그런데 단순히 RGB 밴드 영상에 한 가지 영상분할 기법을 적용하는 것으로는 다양한 분광 특성과 형태를 갖는 여러 대상 개체들을 추출하는데 한계가 있다. 지표면의 피복의 종류를 식별하고, 상태를 모니터링 하는데 효과적인 분광지수는 개체 추출 과정에 효율적으로 이용할 수 있다. 본 연구에서는 영상분할 기술을 기반으로 하여 분광지수를 이용한 보다 효과적인 개체 추출 기술을 제안하고자 하였다. 다양한 종류의 개체를 추출하기 위하여 의사결정 트리 분류 기술을 사용하였으며 고해상도 위성인 WorldView-2의 8밴드 다중분광 영상을 이용한 실험을 통해 각 대상 개체를 추출하기에 적합한 분광지수들을 선택하고 이의 효용성을 평가해보고자 하였다. 그 결과, 건물, 도로, 나지, 식생, 수계, 그림자의 6개 클래스에 대한 개체들을 선택적으로 분류할 수 있었고, 식생지수를 비롯한 다양한 분광지수들이 각 개체의 종류를 선별해내는데 효과적으로 사용될 수 있음을 확인하였다.

• Tuberculosis and Respiratory Diseases
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• 제70권5호
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• pp.423-427
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• 2011

Epithelioid sarcomas are rare soft tissue sarcomas with a high tumor grade and high local recurrence and metastasis rates. Although the lung is the most common site of metastasis, endobronchial metastasis hasn't been reported yet. We now report a case of epithelioid sarcoma with endobronchial metastasis. A 28-year-old man had recurrent pneumothorax and underwent wedge resection. He presented at our hospital with hemoptysis, dyspnea, and chest pain. Chest computed tomography revealed left pneumothorax, multiple lung nodules and endobronchial lesions at the right lower basal lobe. Bronchoscopy showed a hemorrhagic mass obstructing the bronchus of the right lower basal lobe. Magnetic resonance imaging revealed multiple nodular lesions in the left thigh muscles. The bronchoscopic biopsy of the endobronchial lesion and the muscle biopsy of the thigh showed the same feature epithelioid sarcoma. This is the first case report of an epithelioid sarcoma with endobronchial metastasis that was diagnosed by bronchoscopic biopsy.

• Tuberculosis and Respiratory Diseases
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• 제71권5호
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• pp.335-340
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• 2011

Background: Community-acquired pneumonia (CAP) is an important cause of morbidity and mortality throughout the world in all age groups. Viral causes of CAP are less well characterized than bacterial causes. We analyzed the characteristics of hospitalized patients with CAP who had a viral pathogen detected by multiplex polymerase chain reaction (PCR). Methods: Multiplex real-time PCR was performed for respiratory viruses in samples collected from 520 adults who developed CAP at Chungnam National University Hospital. Clinical, laboratory, and radiological features at presentation as well as other epidemiological data were analyzed. Results: Of 520 patients with CAP, a viral pathogen was detected in 60 (11.5%), and influenza A was the most common. The virus detection rate in patients with CAP was highest in November. Two or more pathogens were detected in 13 (21.7%) patients. Seven patients had severe disease and were administered in the intensive care unit. Most patients (49/60, 81.7%) had comorbidities. However, nine (15%) patients had no comorbidities, and their age was <60 years. The ground glass opacity pattern was the most common radiological feature. Seven (11.7%) patients died from CAP. Conclusion: Viral pathogens are commonly detected in patients with CAP, and a respiratory virus may be associated with the severity and outcome of pneumonia. Careful attention should be paid to the viral etiology in adult patients with CAP.

• Tuberculosis and Respiratory Diseases
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• 제40권1호
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• pp.67-71
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• 1993

Bronchial carcinoids were classified as one of the bronchial adenoma group and constituted about 90% of bronchial adenoma. Typical carcinoids are common benign neoplasms of the airway because of their uniform histologic feature, predictable clinical course and good survival after surgical resection. And atypical carcinoid is regarded as a malignant tumor because of its pleomorphic, hyperchromatic nucleus, frequent mitosis and distant metastasis (about 70%). However, typical carcinoids rarely metastasize to regional lymph nodes and such cases would be regarded as a low grade malignancy because their clinical prognosis could be bad. We present a case of typical bronchial carcinoid which metastasize to hilar lymph node who has been followed up 10 months after resection.

• Journal of Mechanical Science and Technology
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• 제14권10호
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• pp.1131-1142
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• 2000

In an effort to illustrate the global variation of SMD (Sauter mean diameter, or $D_{32}$) and AMD (Arithmetic mean diameter, or $D_{10}$) at five axial downstream locations (i. e., at Z=30, 50, 80, 120, and 170 mm) under the different experimental conditions, the radial coordinate is normalized by the spray half-width. Experimental data to analyze the atomization characteristics concerning with an internal mixing type have been obtained using a PDPA(Phase Doppler Particle Analyzer). The air injection pressure was varied from 40 kPa to 120 kPa. In this study, counterflowing internal mixing nozzles manufactured at an angle of $15^{\circ}$with axi-symmetric tangential-drilled four holes have been considered. By comparing the results, it is clearly possible to discern the effects of increasing air pressure, suggesting that the disintegration process is enhanced and finer spray droplets can be obtained under higher air assist. The variations in $D_{32}$ are attributed to the characteristic feature of internal mixing nozzle in which the droplets are preferentially ejected downward with strong axial momentum, and dispersed with the larger droplets which are detected in the spray centerline at the near stations and smaller ones are generated due to further subsequent breakup by higher shear stresses at farther axial locations. The poor atomization around the centre close to the nozzle exit is attributed to the fact that the relatively lower rates of spherical particles are detected and these drops are not subject to instantaneous breakup in spite of the strong axial momentum. However, substantial increases in SMD from the central part toward the edge of the spray as they go farther downstream are mainly due to the fact that the relative velocity of droplet is too low to cause any subsequent disintegration.

• 대한의용생체공학회:의공학회지
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• 제26권6호
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• pp.357-363
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• 2005

Active contour models have been extensively used to segment, match, and track objects of interest in computer vision and image processing applications, particularly to locate object boundaries. With conventional methods an object boundary can be extracted by controlling the internal energy and external energy based on energy minimization. However, this still leaves a number of problems, such as initialization and poor convergence in concave regions. In particular, a contour is unable to enter a concave region based on the stretching and bending characteristic of the internal energy. Therefore, this study proposes a method that controls the internal energy by moving the local perpendicular bisector point of each control point on the contour, and determines the object boundary by minimizing the energy relative to the external energy. Convergence at a concave region can then be effectively implemented as regards the feature of interest using the internal energy, plus several objects can be detected using a multi-detection method based on the initial contour. The proposed method is compared with other conventional methods through objective validation and subjective consideration. As a result, it is anticipated that the proposed method can be efficiently applied to the detection of the pulmonary parenchyma region in medical images.

• 농업과학연구
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• 제37권2호
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• pp.303-308
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• 2010

Surface color is the most important quality factor for the grade evaluation of cherry tomato. Color is one of the representative indicators for the maturity which is closely related to the internal quality of cherry tomato, such as firmness, sugar content, and acidity. This study was carried out to investigate the relationship between surface color and internal quality of cherry tomatoes harvested from both hydroponic and soil culture at different ripening stages. To calculate the color values of cherry tomatoes an automatic color imaging system was constructed. A specially designed image processing algorithm for the color measurement was developed. The color values of L*, a*, b* were calculated from the initial color values of RGB and then compared with the internal quality. Statistical analyses indicated that the internal quality was more highly correlated with the surface color than size of cherry tomatoes. Color image features were also investigated to detect external damage of cherry tomatoes. The value of (R value - R mean value)/R mean value was the most effective image feature for the detection of damaged areas on the surface of cherry tomatoes. The results of this study demonstrated the feasibility of color sorting process as an alternative of the conventional drum type size sorting system for cherry tomato industry.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.1130-1147
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• 2014

Large size ships have a very flexible construction resulting in low resonance frequencies of the structural eigen-modes. This feature increases the dynamic response of the structure on short period waves (springing) and on impulsive wave loads (whipping). This dynamic response in its turn increases both the fatigue damage and the ultimate load on the structure; these aspects illustrate the importance of including the dynamic response into the design loads for these ship types. Experiments have been carried out using a segmented scaled model of a container ship in a Seakeeping Basin. This paper describes the development of the model for these experiments; the choice was made to divide the hull into six rigid segments connected with a flexible beam. In order to model the typical feature of the open structure of the containership that the shear center is well below the keel line of the vessel, the beam was built into the model as low as possible. The model was instrumented with accelerometers and rotation rate gyroscopes on each segment, relative wave height meters and pressure gauges in the bow area. The beam was instrumented with strain gauges to measure the internal loads at the position of each of the cuts. Experiments have been carried out in regular waves at different amplitudes for the same wave period and in long crested irregular waves for a matrix of wave heights and periods. The results of the experiments are compared to results of calculations with a linear model based on potential flow theory that includes the effects of the flexural modes. Some of the tests were repeated with additional links between the segments to increase the model rigidity by several orders of magnitude, in order to compare the loads between a rigid and a flexible model.

• 대한한방내과학회지
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• 제27권2호
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• pp.510-520
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• 2006

Objectives: The aim of this study was to investigate the correlation between fatigue degree and Comprehensive diagnosis of Qui Xui Shui in patients with functional dyspepsia. There again, we investigated an association between scores obtained from Comprehensive diagnosis of Qui Xui Shui and state of skin sympathetic tone or cardiovascular reactivity. Methods: Subjects were 56 patients with Functional dyspepsia and 8 healthy People. Fatigue degree was assessed by questionnaires consisting of subjective complaints of fatigue. Comprehensive diagnoais of Qui Xue Shui was investigated by questionnaire and physical examination, total score and composition score were calculated from the symptom score. Skin sympathetic tone was measured by Ryodoraku Score(RS) and Cardiovascular Reactivity(CV Reactivity) was checked by Pulse diagnostic apparatus. All patients were divided into two groups by RS $40{\mu}A$(below and above) or by CV Reactivity(decreased and increased or not decreased). Results: There was highly significant correlation between Fatigue Degree and total score and each composition score of Comprehensive diagnosis of Qui Xui Shui. And total score of patients was significantly higher than that of health controls : in the patients, females than males. Significance related with the level of RS $40{\mu}Aor$ the state of CV Reactivity were not remarkable in both patients and health control group. Conclusions: Fatigue degree seems to have a special feature reflecting the state of Comprehensive Diagnosis of Qui Xui Shui in patients with functional dyspepsia.