• Title/Summary/Keyword: sampling frame

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The Digital Image Processing Method Using Triple-Density Discrete Wavelet Transformation (3중 밀도 이산 웨이브렛 변환을 이용한 디지털 영상처리 기법)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.3
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    • pp.133-145
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    • 2012
  • This paper describes the high density discrete wavelet transformation which is one that expands an N point signal to M transform coefficients with M > N. The double-density discrete wavelet transform is one of the high density discrete wavelet transformation. This transformation employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. And it is nearly shift-invariant. Similarly, triple-density discrete wavelet transformation is a new set of dyadic wavelet transformation with two generators. The construction provides a higher sampling in both time and frequency. Specifically, the spectrum of the first wavelet is concentrated halfway between the spectrum of the second wavelet and the spectrum of its dilated version. In addition, the second wavelet is translated by half-integers rather than whole-integers in the frame construction. This arrangement leads to high density wavelet transformation. But this new transform is approximately shift-invariant and has intermediate scales. In two dimensions, this transform outperforms the standard and double-density discrete wavelet transformation in terms of multiple directions. Resultingly, the proposed wavelet transformation services good performance in image and video processing fields.

A Study on the Effect of Follow-Up on Mail Survey for Park Users (공원이용자 연구시, Follow-Up 기법이 우송조사법에 미치는 경향에 관한 연구)

  • 홍성권
    • Journal of the Korean Institute of Landscape Architecture
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    • v.21 no.4
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    • pp.29-41
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    • 1994
  • The purposes of this study are (a)to investigate the effect of follow-up on the increase of response rate;(b)to analyze the effect of follow-up on the statistics by predetermined response rates ; therefore, (c)to describe the importance of high response rate and to suggest methods in order to increase response rate in mail survey. Telephone directory of Seoul was utilized as a sampling frame, and modified Total Design Method(TDM) was applied to collect the data. The results are summarized as follows. 1. Final response rate was 76.5% by 2 follow-ups. 2. The first follow-up with telephone call had a significant effect on increase of response rate. As a result, follow-up by postcard in TDM could be omitted in this method. 3. The second follow-up by registered mail did not have a significant effect. Therefore, use of this procedure is depending upon such research situtations as importance of high response rate and cost available. 4. Follow-ups helped to make collected sample highly representative. 5. Most questionnaires were arrived on the first half of data collection period in each follow-up. 6. Most of questionnaires were collected for 10 weeks. Accumulated responses could be fitted by exponential and logistic curve, simultaneously. The fitted curve suggested that eventually limited number of questionnaires by arrived. So, if researchers want higher response rate, they have to conduct more follow-ups. 7. Statistics in the predetermined response rate were not changed significantly. But replications are needed to generalize this result.

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A longitudinal study on the professional architects' recognition about the architectural knowledge assets of healthcare design (의료시설 설계의 건축지식자산에 대한 전문 건축가의 인식특성 종단연구)

  • Kim, Duk-Su
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.16 no.2
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    • pp.47-54
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    • 2010
  • This paper is a longitudinal study, comparing survey results between two time periods. A previous survey was conducted in 1999. After 10 years of the first survey, the second survey was conducted while utilizing the same questionnaire. A list of membership of Korea Institute of Heallthcare Architecture was used as a sampling frame. At the first survey in 1999, questionnaires of 27.3 percentage were returned, and 15.5 percentage in the 2008 survey. Healthcare design is one of the highly specialized design types in architecture. In addition, it is demanded highly specialized knowledge to solve healthcare design problems. As a professional service firm(PSF), architectural firm utilizes knowledge assets to provide design service to clients. Specialized knowledge in question is one of the core assets of PSF. The knowledge generates competitive advantages and plays an effective role as a marketing tool for PSF. However, empirical studies dealing with the knowledge characteristics of specialized design(healthcare) firms were hardly found. Thus, this study aims to trace the professional architects' perception of knowledge demands for task performance and architectural knowledge assets. The results can be used as a reference when a specialized firm in healthcare design initiates to build knowledge assets in it.

Factor's Related to Self-Perceived Health of Young Adults (청년층의 자기인지건강 관련 요인)

  • Cho, Woo-Hyun;Suh, Il;Park, Jong-Ku;Park, Kee-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.33 no.4
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    • pp.415-425
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    • 2000
  • Objectives : To determine which factors are related to young adults perception of their health. Two research questions were asked. Which aspects of health does self-perceived health as a index of general health reflect? Why do two individuals with the same level of general health have different health perceptions? Methods : The sampling frame comprised college or graduate school students, aged 20 to 29, who were members of A, one of the 4 biggest internet communication services. The questionnaires were sent to study samples(n=1,000) and answered by E-mail. Response rate was 37.0%. Results : Firstly, physical health ranked highest and self-perceived health ranked lowest. Secondly, health, anxiety, depression, and self-perceived health showed significant differences between the sexes, with women showing a higher health status in these categories except for self-perceived health. Thirdly, the two factors significantly related to self-perceived health were physical health and self-esteem, as determined by multivariate analysis, Conclusions : The factors significantly related to self-perceived health were physical health and self-esteem. Further studies of the health characteristics of young adults are needed.

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A Stabilization of MC-BCS-SPL Scheme for Distributed Compressed Video Sensing (분산 압축 비디오 센싱을 위한 MC-BCS-SPL 기법의 안정화 알고리즘)

  • Ryu, Joong-seon;Kim, Jin-soo
    • Journal of Korea Multimedia Society
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    • v.20 no.5
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    • pp.731-739
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    • 2017
  • Distributed compressed video sensing (DCVS) is a framework that integrates both compressed sensing and distributed video coding characteristics to achieve a low complexity video sampling. In DCVS schemes, motion estimation & motion compensation is employed at the decoder side, similarly to distributed video coding (DVC), for a low-complex encoder. However, since a simple BCS-SPL algorithm is applied to a residual arising from motion estimation and compensation in conventional MC-BCS-SPL (motion compensated block compressed sensing with smoothed projected Landweber) scheme, the reconstructed visual qualities are severly degraded in Wyner-Ziv (WZ) frames. Furthermore, the scheme takes lots of iteration to reconstruct WZ frames. In this paper, the conventional MC-BCS-SPL algorithm is improved to be operated in more effective way in WZ frames. That is, first, the proposed algorithm calculates a correlation coefficient between two reference key frames and, then, by selecting adaptively the reference frame, the residual reconstruction in pixel domain is performed to the conventional BCS-SPL scheme. Experimental results show that the proposed algorithm achieves significantly better visual qualities than conventional MC-BCS-SPL algorithm, while resulting in the significant reduction of the decoding time.

Multiple failure criteria-based fragility curves for structures equipped with SATMDs

  • Bakhshinezhad, Sina;Mohebbi, Mohtasham
    • Earthquakes and Structures
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    • v.17 no.5
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    • pp.463-475
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    • 2019
  • In this paper, a procedure to develop fragility curves of structures equipped with semi-active tuned mass dampers (SATMDs) considering multiple failure criteria has been presented while accounting for the uncertainties of the input excitation, structure and control device parameters. In this procedure, Latin hypercube sampling (LHS) method has been employed to generate 30 random SATMD-structure systems and nonlinear incremental dynamic analysis (IDA) has been conducted under 20 earthquakes to determine the structural responses, where failure probabilities in each intensity level have been evaluated using Monte Carlo simulation (MCS) method. For numerical analysis, an eight-story nonlinear shear building frame with bilinear hysteresis material behavior has been used. Fragility curves for the structure equipped with optimal SATMDs have been developed considering single and multiple failure criteria for different performance levels and compared with that of uncontrolled structure as well as structure controlled using passive tuned mass damper (TMD). Numerical analysis has shown the capability of SATMDs in significant enhancement of the seismic fragility of the nonlinear structure. Also, considering multiple failure criteria has led to increasing the fragility of the structure. Moreover, it is observed that the influence of the uncertainty of input excitation with respect to the other uncertainties is considerable.

Development of High Tension Tensile Tester for Transmission Line (송배전 선로 고장력 인장시험기 개발)

  • Shin, Dong-Hwa;Lee, Byung-Ho
    • Journal of the Korean Society of Industry Convergence
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    • v.21 no.5
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    • pp.219-225
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    • 2018
  • In this paper, for the testing of tensile strength of dead-end clamp used in transmission line, resulting values were estimated by designing and producing the horizontal version of widely-used vertical tensile tester. Tensile strength test of dead-end clamp for transmission line is essential for quality test of products. Moreover, tensile tester is an equipment that requires high level of reliability which needs to be examined through sampling tests commensurate with total inspection. Frames of tensile tester were made up of H-beams so that it can endure more than 20 [tons] of load capability and the test was implemented for 60[seconds] applying five types of tension. In consequence, the tester could withstand up to 21,600[kg] of weight as well as all types of tension. This newly developed horizontal tensile tester can be utilized in figuring out properties of various materials by estimating tensile strength of materials such as metal, rubber and fiber.

Relationships Among Owner-Manager Characteristics, E-commerce Adoption and Performance of Small and Medium Enterprises (SMEs) in Malaysia

  • KOE, Wei-Loon;WULANDARI, Ririn
    • The Journal of Asian Finance, Economics and Business
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    • v.10 no.1
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    • pp.101-109
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    • 2023
  • This study examined the relationships among owner-manager characteristics, e-commerce adoption, and performance of small and medium enterprises (SMEs) in Malaysia. Although the growth of e-commerce was encouraging in many countries, studies of e-commerce adoption among SMEs in developing countries such as Malaysia are insufficient. Furthermore, studies that investigated individual characteristics and e-commerce adoption are still low in number. This study specifically employed the technology-organization-environmental (TOE) framework to develop its research model. The sample was selected by using a non-probability judgmental sampling technique because the desired population frame was unavailable. A total of 111 owner-managers of SMEs were surveyed using online self-administered questionnaires. Subsequently, the data was analyzed through partial least square-structural equation modeling (PLS-SEM). The results revealed significant relationships between owner-manager characteristics and e-commerce adoption, as well as between e-commerce adoption and the performance of SMEs. The findings suggested that owner-manager characteristics played an important role in determining e-commerce adoption among SMEs. Moreover, e-commerce adoption was crucial in affecting the performance of SMEs. This paper provided new insights into factors affecting e-commerce adoption and firm performance. It could further benefit the government and SMEs in strategizing e-commerce adoption and development, especially in the era of Industrial Revolution 4.0 (IR 4.0) and the post-COVID-19 pandemic.

Basel III Effects on Bank Stability: Empirical Evidence from Emerging Countries

  • ASGHAR, Muhammad;RASHID, Abdul;ABBAS, Zaheer
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.3
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    • pp.347-354
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    • 2022
  • This article examines the influence of Basel III reforms, risk management, and banking sector efficiency on banks' financial stability in emerging countries. The data for this study is collected from various sources. Based on the GDP classification of IMF, the top 22 countries were selected as the sample. The sampling frame includes all six regions of the world including 482 banks and 3022 observations in total. The empirical analysis is carried out by estimating the random effects models. It is found that the effects of capital buffer, liquidity, and risk management practices are significant on financial stability. It is also noticed that the capital buffer has a constructive and significant influence on financial stability. However, liquidity management shows a mixed impact, as in some countries, its impact is positive and significant while, in other countries, it is insignificant. Risk management practices have an overall positive influence on financial stability in the case of large economies. However, results are insignificant in the case of small economies. Bank-specific variables, namely profitability, size, and efficiency have a positive whereas, loan quality has a negative impact on financial stability in the emerging countries. GDP has a positive impact on financial stability whereas inflation and unemployment both have a negative effect on financial stability.

Salient Video Frames Sampling Method Using the Mean of Deep Features for Efficient Model Training (효율적인 모델 학습을 위한 심층 특징의 평균값을 활용한 의미 있는 비디오 프레임 추출 기법)

  • Yoon, Hyeok;Kim, Young-Gi;Han, Ji-Hyeong
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2021.06a
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    • pp.318-321
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    • 2021
  • 최근 정보통신의 발달과 함께 인터넷에 접속하는 사용자 수와 그에 따른 비디오 데이터의 전송량이 늘어나는 추세이다. 이렇게 늘어나는 많은 비디오 데이터를 관리하고 분석하기 위해서 최근에는 딥 러닝 기법을 많이 활용하게 된다. 일반적으로 비디오 데이터에 딥 러닝 모델을 학습할 때 컴퓨터 자원의 한계로 인해 전체 비디오 프레임에서 균등한 간격 또는 무작위로 프레임을 선택하는 방법을 많이 사용한다. 하지만 학습에 사용되는 비디오 데이터는 항상 시간 축에 따라 같은 문맥을 담고 있는 Trimmed 비디오라고 가정할 수가 없다. 만약 같지 않은 문맥을 지닌 Untrimmed 비디오에서 균등한 간격 또는 무작위로 프레임을 선택해서 사용하게 된다면 비디오의 범주와 관련이 없는 프레임이 샘플링 될 가능성이 있기 때문에 모델의 학습 및 최적화에 전혀 도움이 되지 않는다. 이를 해결하기 위해 우리는 각 비디오 프레임에서 심층 특징을 추출하여 평균값을 계산하고 이와 각 추출된 심층특징들과 코사인 유사도를 계산해서 얻은 유사도 점수를 바탕으로 Untrimmed 비디오에서 의미 있는 비디오 프레임을 추출하는 기법을 제안한다. 그리고 Untrimmed 비디오로 구성된 데이터셋으로 유명한 ActivityNet 데이터셋에 대해서 대표적인 2가지 프레임 샘플링 방식(균등한 간격, 무작위)과 비교하여 우리가 제안하는 기법이 Untrimmed 비디오에서 효과적으로 비디오의 범주에 해당하는 의미 있는 프레임 추출이 가능함을 보일 것이다. 우리가 실험에 사용한 코드는 https://github.com/titania7777/VideoFrameSampler에서 확인할 수 있다.

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