• Title/Summary/Keyword: Random Process

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Development of Improved Clustering Harmony Search and its Application to Various Optimization Problems (개선 클러스터링 화음탐색법 개발 및 다양한 최적화문제에 적용)

  • Choi, Jiho;Jung, Donghwi;Kim, Joong Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.630-637
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    • 2018
  • Harmony search (HS) is a recently developed metaheuristic optimization algorithm. HS is inspired by the process of musical improvisation and repeatedly searches for the optimal solution using three operations: random selection, memory recall (or harmony memory consideration), and pitch adjustment. HS has been applied by many researchers in various fields. The increasing complexity of real-world optimization problems has created enormous challenges for the current technique, and improved techniques of optimization algorithms and HS are required. We propose an improved clustering harmony search (ICHS) that uses a clustering technique to group solutions in harmony memory based on their objective function values. The proposed ICHS performs modified harmony memory consideration in which decision variables of solutions in a high-ranked cluster have higher probability of being selected than those in a low-ranked cluster. The ICHS is demonstrated in various optimization problems, including mathematical benchmark functions and water distribution system pipe design problems. The results show that the proposed ICHS outperforms other improved versions of HS.

Structural Response Analysis of a Tension Leg Platform in Multi-directional Irregular Waves (다방향 불규칙파중의 인장계류식 해양구조물의 구조응답 해석)

  • Lee, Soo-Lyong;Suh, Kyu-Youl;Lee, Chang-Ho
    • Journal of Navigation and Port Research
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    • v.31 no.8
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    • pp.675-681
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    • 2007
  • A numerical procedure is described for estimating the effects of the multi-directional irregular waves on the structural responses of the Tension Leg Platform (TLP). The numerical approach is based on a three dimensional source distribution method for hydrodynamic forces, a three dimensional frame analysis method for structural responses, in which the superstructure of TLP is assumed to be flexible instead of rigid. Hydrodynamic and hydrostatic forces on the submerged surface of a TLP have been accurately calculated by excluding the assumption of the slender body theory. The hydrodynamic interactions among TLP members, such as columns and pontoons, and the structural damping are included in structural analysis. The spectral description used in spectral analysis of directional waves for the linear system of a TLP in the frequency domain is sufficient to completely define the structural responses. This is due to both the wave inputs and responses are stationary Gaussian random process of which the statistical properties in the amplitude domain are well known. The numerical results for the linear motion responses and tension variations in regular waves are compared with the experimental and numerical ones, which are obtained in Yoshida et al.(1983). The results of comparison confirmed the validity of the proposed approach.

An Analysis on the Effects of Mathematics Learning through Tessellation Activities on Spatial Sense (테셀레이션(Tessellation)을 활용한 수학학습이 공간감각능력에 미치는 효과 분석)

  • Park, Hyun-Mee;Kang, Shin-Po;Kim, Sung-Joon
    • Journal of Elementary Mathematics Education in Korea
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    • v.11 no.2
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    • pp.117-136
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    • 2007
  • The purpose of this study was to analyze the effects of mathematics learning through tessellation activities on the improvement of spatial sense and to find out a better mathematics teaching method that could further develop spatial sense. For this purpose, the following questions were attempted; Can mathematics learning using tessellation activities develop spatial sense? In odor to test this hypothesis, twenty-four fifth graders of a class were selected at random. And the experimental group was divided into four groups according to gender and academic performance. The groups were protested and post-tested to determine results based on the quasi-experimental design(i.e. one-group pretest-post test design). The process of this study was checking spatial sense for a common evaluation of experimental group. In this study, tangram, pattern block, and GSP was used for mathematics learning through tessellation activities during each independent-study, discretion-activity, and math class. The instrument used in this study was a spatial sense test and pretest and post-test were implemented with the same instrument(i.e. K-WISC-III Activity Test). In conclusion, mathematics learning through tessellation activities with tangram, pattern block, and GSP is an effective teaching and learning method for the improvement of the spatial sense.

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Breast and Cervical Cancer Screening Practice of Women in Suwon City (수원시 여성들의 여성암 검진에 관한 조사연구)

  • 송미숙;전기홍;송현종
    • Health Policy and Management
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    • v.9 no.1
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    • pp.139-155
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    • 1999
  • This study was performed to assess the practice behavior and the need for cancer screening in order to design the community projects in Suwon city. A random sample of urban married women was surveyed on knowledge, attitude, and practice of breast and cervical cancer screening by telephone from April 28th to May 19th. Four hundred two married women completed the questionnaire, and the results were as follows: 1. Urban women were not generally knowledgeable about symptoms, signs and etiology of breast and cervical cancer. Only 11.4% of respondents were fully aware of those subjects. 2. Two hundred eighty six repondents(71.1%) reported having had a mammogram or Pap smear, while 116 respondents(28.9%) reported never having had a mammogram nor Pap smear. 3. The rate of mammogram increased by age and income status significantly(p〈0.05). 4. The majority(73.1%) of women who had a mammogram reported that it was part of a routine physical examination and another 24.3% of the women reported that they had a mammogram for specific breast problems. Meanwhile, the reasons reported for never having a mammogram were as follows; never had any problems (72.1%), no chance(11.2%), no time(4.3%). 5. The main factors associated with adherence to mammography screening guidelines was monthly income status. 6. The majority(80.6%) of women who had a Pap smear reported that it was part of a routine physical examination and another 16.0% of the women reported that it was part of a routine physical examination and another 16.0% of the women reported that they had a Pap smear for specific uterus problems. Meanwhile, the reasons reported for never having a Pap smear were: never had any problems(69.0%) and no chance(11.5%) 7. Women with higher income status were most likely to have a Pap smear regularly (p〈0.01), and the rate of Pap smear increased by education level significantly(p〈0.05). The main factors associated with adherence to Pap smear screening guidelines were education level and monthly income status, similar to those of mammograph. These findings indicate that married women in Suwon city show a lower rate of breast and cervical cancer screening practice than that of developed countries. The rate of mammograph was especially low. It is, therefore, suggested that cost, environmental factors, process, and information for screening tests be considered more programmatically before designing a community project for breast and cervical cancer screening.

Analysis of Ski Socialization Process of Undergraduates (대학생의 스키사회화 과정 분석)

  • Song, Kang-Young;Kim, Kyong-Sik
    • The Journal of the Korea Contents Association
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    • v.7 no.9
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    • pp.167-175
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    • 2007
  • The purposes of this study were to examine the effect of interest and participation in ski, encouragement to participate in ski, and attitude to ski of significant others on the socialization. To attain the goal of the study described above paragraphs, the ski class participant of the university located in Seoul, 2005 year were set as a collected group. Then, using the cluster random sampling method, finally drew out and analyzed 200 people in total. The result of reliability check up was here below; over Chronbach's $\alpha$=.600. To analyze materials, confirmatory factor analysis, logistic regression analysis and multiple regression analysis were used as statistic analysis techniques. The conclusion based on above study method and the result of material analysis are below. Based upon the result of the study, the following conclusions appear warranted: First, significant others influence on the ski participation experience of the undergraduate. Second, significant others influence on the ski participation frequencies of the undergraduate. Third, significant others influence on the ski participation period of the undergraduate. Fourth, significant others influence on the ski participation skill of the undergraduate.

Submucosal Tumor Analysis of Endoscopic Ultrasonography Images (내시경 초음파 영상의 점막하 종양 분석)

  • Kim, Kwang-Baek
    • Journal of Korea Multimedia Society
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    • v.13 no.7
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    • pp.1044-1050
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    • 2010
  • Endoscopic ultrasonography is a medical procedure in endoscopy combined with ultrasound to obtain images of the internal organs. It is useful to have a predictive pathological manifestation since a doctor can observe tumors under mucosa. However, it is often subjective to judge the degree of malignant degeneration of tumors. Thus, in this paper, we propose a feature analysis procedure to make the pathological manifestation more objective so as to improve the accuracy and recall of the diagnosis. In the process, we extract the ultrasound region from the image obtained by endoscopic ultrasonography. It is necessary to standardize the intensity of this region with the intensity of water region as a base since frequently found small intensity difference is only to be inefficient in the analysis. Then, we analyze the spot region with high echo and calcium deposited region by applying LVQ algorithm and bit plane partitioning procedure to tumor regions selected by medical expert. For detailed analysis, features such as intensity value, intensity information included within two random points chosen by medical expert in tumor region, and the slant of outline of tumor region in order to decide the degree of malignant degeneration. Such procedure is proven to be helpful for medical experts in tumor analysis.

Feature Analysis of Endoscopic Ultrasonography Images (내시경 초음파 영상의 특징 분석)

  • Kim, kwang-beak;Kang, hyo-joo;Kim, mi-jeong;Kim, gwang-ha
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.390-397
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    • 2009
  • Endoscopic ultrasonography is a medical procedure in endoscopy combined with ultrasound to obtain images of the internal organs. It is useful to have a predictive pathological manifestation since a doctor can observe tumors under mucosa. However, it is often subjective to judge the degree of malignant degeneration of tumors. Thus, in this paper, we propose a feature analysis procedure to make the pathological manifestation more objective so as to improve the accuracy and recall of the diagnosis. In the process, we extract the ultrasound region from the image obtained by endoscopic ultrasonography. It is necessary to standardize the intensity of this region with the intensity of water region as a base since frequently found small intensity difference is only to be inefficient in the analysis. Then, we analyze the spot region with high echo and calcium deposited region by applying LVQ algorithm and bit plane partitioning procedure to tumor regions selected by medical expert. For detailed analysis, features such as intensity value, intensity information included within two random points chosen by medical expert in tumor region, and the slant of outline of tumor region in order to decide the degree of malignant degeneration. Such procedure is proven to be helpful for medical experts in tumor analysis.

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An Adaptive Information Hiding Technique of JPEG2000-based Image using Chaotic System (카오스 시스템을 이용한 JPEG2000-기반 영상의 적응적 정보 은닉 기술)

  • 김수민;서영호;김동욱
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.4
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    • pp.9-21
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    • 2004
  • In this paper, we proposed the image hiding method which decreases calculation amount by encrypt partial data using discrete wavelet transform and linear scale quantization which were adopted as the main technique for frequency transform in JPEG2000 standard. Also we used the chaotic system which has smaller calculation amount than other encryption algorithms and then dramatically decreased calculation amount. This method operates encryption process between quantization and entropy coding for preserving compression ratio of images and uses the subband selection method and the random changing method using the chaotic system. For ciphering the quantization index we use a novel image encryption algerian of cyclically shifted in the right or left direction and encrypts two quantization assignment method (Top-down/Reflection code), made change of data less. Also, suggested encryption method to JPEG2000 progressive transmission. The experiments have been performed with the proposed methods implemented in software for about 500 images. consequently, we are sure that the proposed are efficient image encryption methods to acquire the high encryption effect with small amount of encryption. It has been shown that there exits a relation of trade-off between the execution time and the effect of the encryption. It means that the proposed methods can be selectively used according to the application areas. Also, because the proposed methods are performed in the application layer, they are expected to be a good solution for the end-to-end security problem, which is appearing as one of the important problems in the networks with both wired and wireless sections.

Wavelet-Based Digital Watermarking Using Level-Adaptive Thresholding (레벨 적응적 이치화를 이용한 웨이블릿 기반의 디지털 워터마킹)

  • Kim, Jong-Ryul;Mun, Young-Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.1
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    • pp.1-10
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    • 2000
  • In this paper, a new digital watermarking algorithm using wavelet transform is proposed. Wavelet transform is widely used for image processing, because of its multiresolution characteristic which conforms to the principles of the human visual system(HVS). It is also very efficient for localizing images in the spatial and frequency domain. Since wavelet coefficients can be characterized by the gaussian distribution, the proposed algorithm uses a gaussian distributed random vector as the watermark in order to achieve invisibility and robustness. After the original image is transformed using DWT(Discrete Wavelet Transform), the coefficients of all subbands including LL subband are utilized to equally embed the watermark to the whole image. To select perceptually significant coefficients for each subband, we use level-adaptive thresholding. The watermark is embedded to the selected coeffocoents, using different scale factors according to the wavelet characteristics. In the process of watermark detection, the similarity between the original watermark and the extracted watermark is calculated by using vector projection method. We analyze the performance of the proposed algorithm, compared with other transform-domain watermarking methods. The experimental results tested on various images show that the proposed watermark is less visible to human eyes and more robust to image compressions, image processings, geometric transformations and various noises, than the existing methods.

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A study of the Impact of Fourism Attractions and Images on the Destination Development Patterns (관광 매력성과 이미지가 관광지 개발유형에 미치는 영향 연구)

  • 김계섭;김선영
    • Journal of Applied Tourism Food and Beverage Management and Research
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    • v.12 no.1
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    • pp.79-110
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    • 2001
  • Tourist Destination is based on tourism attractions. Components of Tourism attraction are included tourism resources, entertainment facilities, transportation, accommodation, infrastructure, assistance facilities & service, hospitality, information facilities & service, and retailing & service. Tourism resources of them is the key to determine destination development pattern, because tourism attraction that attract tourists is based on tourism resources. Therefore, there are need to study what is tourism attraction of destination at the view of tourists and what is destination development pattern based on it to develop tourism attraction that is able appeal tourists. The purpose of this study is to examine what effect of tourism attraction affects destination development pattern. This study defined Haeundae, Kwanganri, Songjung, Taejongdae in Pusan, Korea as research areas. Research data were collected from 300 respondents by a simple random sampling method. A final 284 usable questionaries were used for empirical analysis after data purification process. Reliability and validity of the scale on the tourism attraction, destination image, and facility needs have been evaluated using Cronbach $\alpha$, item-total correlations. This study analyzed the factors of the tourism attraction and destination images. The result obtained that tourism attraction is divided relaxation attraction, local activity attraction, culture . nature attraction and touring circuit attraction, and destination image is divided culture . urban attractiveness, touring attractiveness, local . stay attractiveness, convenience of travel and relativeness for destination investigated. ANOVA and regression (stepwise) were used to test hypotheses. Based on the results of hypotheses testing, major findings of the empirical research are as follow : 1. The tourism attraction and destination image are significantly different, but facility needs are not significantly by destinations (e. g. Haeundae, Kwanganri, Songjung, Taejongdae) . 2. Destination development pattern is a(fact by the tourism attraction in partial. In case of Haeundea, relaxation attraction take effect partially spa, history and marine/spa tourism. 3. The destination development pattern is influenced by the destination image in partial. In case of Kwanganri, the natural . activity attractiveness and urban tourism images have been found as influential factors that affect marine tourism. 4. The destination images are influenced the physical attributes in literature review, but the destination image are taken effect partially the tourism attraction in this study. 5. Destination development pattern are influenced by the tourism attraction and the destination image partially. This research has provided a variety of practical suggestions. Especially, it was suggested that the destination have appeal to tourists by strengthening attraction and improving weakness. Also, we need to specialize destination in same destination development pattern.

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