• 디지털산업정보학회논문지
• /
• 제7권4호
• /
• pp.119-131
• /
• 2011

In this paper, we explore the application of 2-D dual-tree discrete wavelet transform (DDWT), which is a directional and redundant transform, for image coding. DDWT main property is a more computationally efficient approach to shift invariance. Also, the DDWT gives much better directional selectivity when filtering multidimensional signals. The dual-tree DWT of a signal is implemented using two critically-sampled DWTs in parallel on the same data. The transform is 2-times expansive because for an N-point signal it gives 2N DWT coefficients. If the filters are designed is a specific way, then the sub-band signals of the upper DWT can be interpreted as the real part of a complex wavelet transform, and sub-band signals of the lower DWT can be interpreted as the imaginary part. The quincunx lattice is a sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Quincunx lattice yields a non separable 2D-wavelet transform, which is also symmetric in both horizontal and vertical direction. And non-separable wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, non-separable image processing using DDWT services good performance.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권2호
• /
• pp.131-141
• /
• 2020

This study examines the poverty indicators in Northeast region of Thailand by adopting the global Multidimensional Poverty Index (MPI) methodology and the national survey of Minimum Basic Needs (MBN) of Thailand. Data are collected from three different districts in Khon Kaen province namely: Khok Po Chai, Sam Sung, and Nam Pong. The sample size is 187 households. Data analysis uses Ordinary Least Square (OLS) regression approach and includes 7 dimensions of poverty (health, environment, education, economy, Thai value, asset? empowerment, and digital literacy) with a total of 41 indicators. This study has found that poverty indicators in Khon Kaen province remains centered around the aspects of health and employment dimensions. While a change of family structure in the Thai society since 1960s reduces the family size, household saving substantially increases over the years. The effects of health dimension in poverty, on the other hand, appears on the other poverty dimension of Thai value, which include (1) a bad living habit of head of household (smoke or alcohol consumption) that links with illness and disease, (2) religious practice, and (3) chronic illness. Lastly, there are income gaps of different careers in the area, which suggests the issue of income inequality.

• 한국직업건강간호학회지
• /
• 제23권3호
• /
• pp.134-145
• /
• 2014

Purpose: The purpose of this study was to identify factors affecting clinical nurses' presenteeism. Methods: A descriptive cross-sectional design was used in which participants completed self-report questionnaires that consisted of measures for nurses' job satisfaction, job stress, professionalism and presenteeism. 267 nurses working in general hospital participated in this study. Logistic regression analysis was used to estimate predictors of the presenteeism in clinical nurses. Results: 250 nurses experienced one or more health problems last one month. The group who experienced presenteeism during the last one year had significant differences in professionalism and perceived productivity. Predictors of sickness presenteeism in clinical nurses included work experience, total health problem and last 1 year absenteeism. Last 1 year absenteeism and total health problem were strongly related to presenteeism in clinical nurses. Conclusion: Major findings of this study indicated that in dealing with nurses' presenteeism, not only managing nurses' job stress and job satisfaction but also providing flexible work schedule and increasing staffing level as an organizational approach are necessary to be considered. Further repeated and expanded research is needed to explore the multidimensional aspects of nurses' presenteeism including a broad range of work setting and the influence of Korean nurses' organizational culture on presenteeism.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (B)
• /
• pp.37-39
• /
• 2005

본 논문에서는 기존의 밀도 기반 전지 클러스터링 알고리즘의 성능을 개선한 밀도 기반 클러스터링의 근사적 접근법을 제안한다. 기존의 밀도 기반 전지 알고리즘은 다차원 색인의 많은 검색 공간을 빠르게 전지하면서도 원하는 클러스터를 정확히 찾아내는 특징을 가지고 있다. 그러나 기존 알고리즘은 전지를 위한 한계 값 설정을 위하여 단말 영역들의 밀도 값을 사용함으로써, 내부 영역에 속한 단말 영역들 간의 밀도 편차가 큰 경우 전지 여부에 대한 판별이 빨리 이루어지지 않는다. 또한, 최악의 경우에는 모든 단말 페이지를 검색하여야 하고, 이에 따라 성능이 저하될 수 있다. 반면에 제안하는 근사적 접근법에서는 한계 값 설정을 위해 단말 영역이 아닌 내부 영역의 밀도 값을 사용한다. 일반적으로, 내부 영역들 간의 밀도 편차는 단말 영역들 간의 밀도 편차보다 크지 않으므로, 근사 밀도 기반 전지 알고리즘에서는 더욱 많은 검색 공간의 전지 여부의 빨리 판별할 수 있게 된다. 성능 평가 실험을 수행한 결과, 제안한 알고리즘은 기존의 알고리즘과 비교하여 정확성 측면에서는 큰 차이가 없는 반면 수행 시간 측면에서는 최대 $17\%$의 성능 향상 효과가 있는 것으로 나타났다.

• 대한원격탐사학회지
• /
• 제1권1호
• /
• pp.5-27
• /
• 1985

A hill-sliding technique was devised to extract Gaussian clusters from the multivariate probability density estimates of sample data for the first step of iterative unsupervised classification. The underlying assumption in this approach was that each cluster possessed a unimodal normal distribution. The key idea was that a clustering function proposed could distinguish elements of a cluster under formation from the rest in the feature space. Initial clusters were extracted one by one according to the hill-sliding tactics. A dimensionless cluster compactness parameter was proposed as a universal measure of cluster goodness and used satisfactorily in test runs with Landsat multispectral scanner (MSS) data. The normalized divergence, defined by the cluster divergence divided by the entropy of the entire sample data, was utilized as a general separability measure between clusters. An overall clustering objective function was set forth in terms of cluster covariance matrices, from which the cluster compactness measure could be deduced. Minimal improvement of initial data partitioning was evaluated by this objective function in eliminating scattered sparse data points. The hill-sliding clustering technique developed herein has the potential applicability to decomposition of any multivariate mixture distribution into a number of unimodal distributions when an appropriate diatribution function to the data set is employed.

• Computers and Concrete
• /
• 제24권4호
• /
• pp.313-327
• /
• 2019

The purpose of the present study is to present a new approach to designing and selecting the details of multidimensional continuous RC beam by applying all strength, serviceability, ductility and other constraints based on ACI318-14 using Teaching Learning Based Optimization (TLBO) algorithm. The optimum reinforcement detailing of longitudinal bars is done in two steps. in the first stage, only the dimensions of the beam in each span are considered as the variables of the optimization algorithm. in the second stage, the optimal design of the longitudinal bars of the beam is made according to the first step inputs. In the optimum shear reinforcement, using gradient-based methods, the most optimal possible mode is selected based on the existing assumptions. The objective function in this study is a cost function that includes the cost of concrete, formwork and reinforcing steel bars. The steel used in the objective function is the sum of longitudinal and shear bars. The use of a catalog list consisting of all existing patterns of longitudinal bars based on the minimum rules of the regulation in the second stage, leads to a sharp reduction in the volume of calculations and the achievement of the best solution. Three example with varying degrees of complexity, have been selected in order to investigate the optimal design of the longitudinal and shear reinforcement of continuous beam.

• Nuclear Engineering and Technology
• /
• 제53권3호
• /
• pp.776-792
• /
• 2021

Conventional integral effect test facilities were constructed to enable the precise observation of thermal-hydraulic phenomena and reactor behaviors under postulated accident conditions to prove reactor safety. Although these facilities improved the understanding of thermal-hydraulic phenomena and reactor safety, applications of new technologies and their performance tests have been limited owing to the cost and large scale of the facilities. Various nuclear technologies converging 4th industrial revolution technologies such as artificial intelligence, drone, and 3D printing, are being developed to improve plant management strategies. Additionally, new conceptual passive safety systems are being developed to enhance reactor safety. A new integral effect test facility having a noticeable scaling ratio, i.e., the (UNIST reactor innovation loop (URI-LO), is designed and constructed to improve the technical quality of these technologies by performance and feasibility tests. In particular, the URI-LO, which is constructed using a transparent material, enables better visualization and provides physical insights on multidimensional phenomena inside the reactor system. The facility design based on three-level approach is qualitatively validated with preliminary analyses, and its functionality as a test facility is confirmed through a series of experiments. The design feature, design validation, functionality test, and future utilization of the URI-LO are introduced.

• 한국의류학회지
• /
• 제43권3호
• /
• pp.384-404
• /
• 2019

This study investigates the multidimensional structure of apparel design evaluation criteria and the details of each criterion by exploring how female college students majoring in apparel design in their 20s evaluate apparel design based on an exploratory approach. Data were analyzed through a categorization method of qualitative data after collecting from a literature review and three focus group interviews. The results identified the six evaluation criteria of apparel design (functional usefulness, convenience, aesthetics, psychological self suitability, social activity usefulness, and fashion trend). Functional usefulness and convenience assessed the extent to which primary features of apparel are reflected in apparel design, and aesthetics evaluated the aesthetic beauty of apparel design. Psychological self suitability estimated the extent to which apparel design expressed psychological self properly, and social activity usefulness appraised the extent to which apparel design contributed to the social activities of wearers. Last, fashion trend assessed the extent to which apparel design reflected fashion trend. The study results provide meaningful implications towards an apparel industry that wants to develop apparel design that appeals to consumers, educational institutions that aim to cultivate well-trained professionals in the apparel industry, and consumers who want to purchase clothes of satisfactory design.

• 한국정보시스템학회지:정보시스템연구
• /
• 제28권3호
• /
• pp.39-58
• /
• 2019

Purpose A digital twin is a digital replication of a physical system. Gartner identified the digital twin as one of the Gartner Top 10 Strategic Technology Trend for three years from 2017. The rapid development of the digital twin market is expected to bring about innovation and change throughout society, and much research has been done recently in academia. In this research, we tried to explore the main research trends for digital twin research. Design/methodology/approach We collected the digital twin research from Web of Science, and analyzed 804 articles that was published during time span of 2010-2018. A total of 41 key authors were selected based on the frequency of citation. We created a co-citation matrix for the core authors, and performed multivariate analysis such as cluster analysis and multidimensional scaling. We also conducted social network analysis to find the influential researchers in digital twin research. Findings We identified four major sub- areas of digital twin research: "Infrastructure", "Prospects and Challenges", "Security", and "Smart Manufacturing". We also identified the most influential researchers in digital twin research: Lee EA, Rajkumar R, Wan J, Karnouskos S, Kim K, and Cardenas AA. Limitation and further research suggestion were also discussed as a concluding remarks.

• 아태비즈니스연구
• /
• 제11권4호
• /
• pp.49-63
• /
• 2020

Purpose - This study aims to assess six aspects of resident satisfaction (satisfaction with room, home, social interaction, meals service, staff care, and resident involvement) and to identify the most influential aspect of satisfaction upon word-of-mouth (WOM) intention in a continuing care retirement community (CCRC). Design/methodology/approach - A total of 293 paper survey questionnaires with a cover letter and postage paid envelopes were mailed to the CCRC residents. To test reliability and validity of the multidimensional resident satisfaction, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used. Then, the structural equation modeling technique (SEM) was applied to test causal relationship between resident satisfaction and WOM intention. Multiple regression was used to identify the most influential aspect of resident satisfaction on WOM intention in the CCRC. Findings - The results of EFA and CFA on the 157 responses received out of the total 293 surveys indicated that six dimensions of resident satisfaction were statistically distinct. Among the six dimensions, satisfaction with resident involvement, social interaction, and staff care significantly influenced their WOM intention. Furthermore, the most influential aspect of satisfaction upon WOM intention was resident involvement. Research implications or Originality - This study empirically tested the six dimensions of CCRC resident satisfaction, and identified resident involvement as the most influential factor upon WOM intention in a CCRC where WOM intentions plays a crucial role during the selection process of prospective residents.