• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.5
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• pp.2414-2433
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• 2019

The aim of this paper is to design a 3D laser radar prototype based on laser triangulation. The mathematical model of distance sensitivity is deduced; a pixel-distance conversion formula is discussed and used to complete 3D scanning. The center position extraction algorithm of the spot is proposed, and the error of the linear laser, camera distortion and installation are corrected by using the proposed weighted average algorithm. Finally, the three-dimensional analytic computational algorithm is given to transform the measured distance into point cloud data. The experimental results show that this 3D laser radar can accomplish the 3D object scanning and the environment 3D reconstruction task. In addition, the experiment result proves that the product of the camera focal length and the baseline length is the key factor to influence measurement accuracy.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.9
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• pp.200-207
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• 2014

Arrhythmia electrocardiogram signal contains a specific unusual heartbeat with abnormal morphology. Because unusual heartbeat is useful for diagnosis and classification of various diseases, such as arrhythmia, detection of unusual heartbeat from the arrhythmic ECG signal is very important. Amplitude and kurtosis at R-peak point and RR interval are characteristics of ECG signal on R-wave. In this paper, we provide a method for detecting unusual heartbeat based on these. Through the value of the attribute deviates more from the average value if unusual heartbeat is more certainly, the proposed method detects unusual heartbeat in order using the mean and standard deviation. From 15 ECG signals of MIT-BIH arrhythmia database which has R-wave distortion, we compare the result of conventional method which uses the fixed threshold value and the result of proposed method. Throughout the experiment, the sensitivity is significantly increased to 97% from 50% using the proposed method.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.259-266
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• 2007

The parameters of electric acoustic characteristic used as standards to evaluate the performance of a small microphone are composed of sensitivity, harmonic distortion, frequency response, directivity and others. Such characteristic parameters should be designed differently depending on a purpose, so it is important to verify whether a small microphone was made appropriately for the purpose after measuring the acoustic characteristics. Therefore, a system that can measure the acoustic characteristic parameters of a small microphone using DSP, not only simultaneously but also in real-time, was implemented in this paper. To verify the implemented system, four kinds of microphones were measured and the results were compared with the data values of the acoustic characteristics of each microphone. There were a little discrepancy between them because the conditions when measuring the characteristics were not identical. But it was verified that the errors are within the error tolerance and it proved that the system can be used in place of the conventional equipment used in measuring the acoustic characteristics of small microphones.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.627-632
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• 2021

ITL (information-theoretic learning) has been applied successfully to adaptive signal processing and machine learning applications, but there are difficulties in deciding the kernel size, which has a great impact on the system performance. The correntropy algorithm, one of the ITL methods, has superior properties of impulsive-noise robustness and channel-distortion compensation. On the other hand, it is also sensitive to the kernel sizes that can lead to system instability. In this paper, considering the sensitivity of the kernel size cubed in the denominator of the cost function slope, a new adaptive kernel estimation method using the rate of change in error power in respect to the kernel size variation is proposed for the correntropy algorithm. In a distortion-compensation experiment for impulsive-noise and multipath-distorted channel, the performance of the proposed kernel-adjusted correntropy algorithm was examined. The proposed method shows a two times faster convergence speed than the conventional algorithm with a fixed kernel size. In addition, the proposed algorithm converged appropriately for kernel sizes ranging from 2.0 to 6.0. Hence, the proposed method has a wide acceptable margin of initial kernel sizes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.2
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• pp.369-377
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• 2008

Though the Hough transform(HT) is a well-known method for detecting analytical shape represented by a number of free parameters, the basic property of the HT, the one-to-many mapping from an image spare to a Hough space, causes the innate problem, the sensitivity to noise. This basic problem also deteriorates the quality of detected lines and makes the detected line deviated from the real one or generates some bogus, multiple lines where only one real line exists. The size of Hough space also affects the quality of detected lines. In this paper, we analyzed the line distortions in the traditional Hough transform and showed that the distortions are relieved in the edge strength Hough transform(ESHT), which is a modified HT. However the usage of expanded edge and edge strength in ESHT can cause some new line distortions which do not exist in the HT. These new ones can be solved by a proper setting of decreasing and broadening parameter values and the optimal values can be determined only by some pre-determined values. We also illustrated several examples to show the distortion-decreasing property of ESHT.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.1
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• pp.103-122
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• 2007

Fashion have been expressed by a face through various a period, social change, and various culture changing. Human expresses as "Transformation" by applying these needs of changing to the fashion. A origin tribe expressed its own self by using direct body transformation and extreme decorations in the past. However, human express creative and esthetic desire based on shape, material, and transformation method in the present time characteristics of the body. Exceptional transformation breaking a existing fixed idea appeared frequently due to dissolution through transformation which is positive expression method in the fashion from 20th century. As a results, followings are obtained in this study. First, human body transforms by using a tool or intermediation in investigation of aesthetic meaning for human body. The object, Transformation, is stably transformed by disintegration, distortion, exaggeration and simplification reduction, as design's sensitivity. Second, transformation from relation of clothing composition is expressed by extension, reduction, simplification, and dissolution. In transformation from original tribe's sensitivity, past decorative desire lead to transformation of human body. To give variable change from past to present fashion, external formative will is introduced. Then, extreme expression is made by direct transformation of clothing type. It seems to be accomplished that human body's expression method is continuously changed into extension, exaggeration, reduction, and dissolution from transformation method as described before. Transformation of modem fashion is expression method by creative supervision. Extreme transformation substituted body's each part is based on immanent play and representative satisfaction. Through these transformation, it is judged that variety of creative type is achieved.

• Spatial Information Research
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• v.9 no.1
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• pp.1-13
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• 2001

Nowadays, SAR Interferometry is actively being studied as a new technique in topographic mapping using satellite imagery. It extracts height values using phase information derived by two SAR imageries covering same areas. Unlike when using SPOT imagery, it is not affected by atmospheric conditions and time. So to speak, we can say that SAR Interferometry is flexible in imagery acquisitions and can get height data economically over wide area. So, it is expected that SAR Interferometry will be widely using in GIS applications. But, in some area occurring geometric distortion, height data are misjudged or not extracted depending on phase unwrapping algorithms. IN the case of ERS tandem data, the accuracy of height data was worst in mountain area. It is the because of the short incidence angle resulted in layover effect. Of the phase unwrapping algorithms, path-following was better in height accuracy but could not get data in layover area. In this area, we could get height data using Height Sensitivity. In concludion, we could get DEM that maintained the accuracy of path-following method and have overall data across imagery.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.2
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• pp.178-185
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• 2014

This paper describes a fabrication multiplexing sensor probe that employs a fiber Bragg grating(FBG) based on multiple measurements to determine the blade deflection of a wind power generator the reliability analysis of this probe is also presented. To diminish the temperature sensitivity of the FBG sensor, we form multiple CFRPs onto the upper and lower layers of the FBG and package it with an epoxy resin. As a result, the depth of the CFRP is 1mm, and the temperature sensitivity is $2.39pm/^{\circ}C$. We construct a sensor network utilizing the fabricated sensor with a blade beam model. As the number of pendulums is increased on the fore-end of the beam, the strain value is measured. The strain variation is calculated from the measurement of the load on the blade beam model by monitoring the strain of the FBG sensor. When the linear equation is applied, the strain error is 0.4% and when the finite difference method is used, the tip deflection error is 3.3%. The displacement error derived from the strain value of the FBG sensor is 4.39%. The calculated result between the measured value of the dead-end of the beam and the strain is less than 2.46% tip distortion error. Therefore, our proposed multiplexing sensor probe is a low-cost and high-reliability solution for a commercial wind power generator.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.169-173
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• 2008

Purpose: Sacrococcygeal pilonidal sinus is a chronic inflammatory disease that mostly affects young people, which warrants surgical intervention. Although many surgical methods have been suggested, an optimal surgical method remains controversial because of high recurrence rates and postoperative complications. The objective of this study is to evaluate the results of wide excision and coverage with fasciocutaneous advancement flap for the treatment of sacrococcygeal pilonidal sinus, and to assess the usefulness of this method Methods: From May 1995 to October 2006, the authors treated 19 patients with the use of coverage with fasciocutaneous flap after wide excision. The results were evaluated regarding recurrence rates, complications, and the change in sensitivity of the gluteal region after surgery. The follow-up period was 7 to 142 months (mean, 76 months). All patients were male. Results: Postoperative complications were wound infection at the suction drain insertion site and skin necrosis around the suture margin in one case, respectively. During the follow up period, only one recurrence (5.3%) was seen in fifth postoperative month, which was successfully treated by the same operative procedure. There was no other complications such as seroma, hematoma, wound dehiscence and flap loss. Extensive scarring and anatomic distortion did not occur in the reconstructed area. In addition, sensitivity of the gluteal region did not diminish. The aesthetic results were satisfactory for all patients as well. Conclusion: The authors advocate that fasciocutaneous flap closure be a good alternative method to cover defects after the excision of sacrococcygeal pilonidal sinus.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.7-11
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• 2003

The selection of a test as a reference with no perfect sensitivity and specificity may lead to bias, yielding distortion of the diagnostic performance. This means it is inappropriate to use imperfect diagnostic tests as a reference method to identify infected patients in clinical environments. In this study, diagnostic performance of rapid urease test, polymerase chain reaction (PCR), and histology of gastric biopsy specimens for diagnosing Helicobacter pylori infection separately and in combination was estimated by using non-linear regression. Based on this approach, the sensitivity, specificity and likelihood ration positive and negative values for each test were as follows: urease test 99.9%, 99.9%, 99.9%, 99.6%, respectively; PCR 88.6%, 99.9%, 99.9%, 70.5%, respectively; histology 78.3%, 97%, 78.3%, 97%, respectively. Predictive values for positive and negative changes with varying Combination of three diagnostic tests employed in the study gives no substantial benefit for practitioners to screen infected patients, and urease test or PCR represents an appropriate single test in clinical environments.