• 한국콘텐츠학회논문지
• /
• 제7권7호
• /
• pp.1-10
• /
• 2007

본 논문에서는 도로망에서 이동하는 객체들의 현재 위치를 효율적으로 갱신하는 색인 기법을 제안한다. 기존의 도로망 모델은 이웃한 도로 세그먼트의 연결 정보를 포함하지 않기 때문에 객체가 이웃한 도로 세그먼트로 이동할 때 갱신 성능을 저하시킨다. 본 논문에서는 이러한 문제점을 해결하기 위해 교차점 기반 도로망 모델과 새로운 색인 구조를 제안한다. 제안하는 교차점 기반 도로망 모델은 도로를 분할할 때 교차점을 포함하도록 분할하여 연결 정보가 유지되도록 한다. 성능 평가를 통해 제안하는 색인 기법이 기존 색인 구조에 비해 이동 객체의 갱신 성능이 3배 향상됨을 보인다.

• Journal of Information Technology Applications and Management
• /
• 제22권2호
• /
• pp.71-93
• /
• 2015

Due to the rapid development of information communication technology, employees have conducted their tasks with smart devices such as smartphones and tablet PCs in the midst of after work hours. In line with this phenomenon, we have examined the relationships among technostress, work connectivity behavior after hours (WCBA) and technostress inhibitors and job satisfaction. Based on the results of prior research, we developed and tested our research model which posits the certain factors such as technostress, WCBA and technostress inhibitors affect work-life conflicts which, in turn influence employees' job satisfaction. Survey data collected from 345 users who have experiences on using smart devices was used to test the model using PLS (partial least squares). In this study, we found that technostress and WCBA were positively related to the work-life conflicts. We also found that the relationship between technostress inhibitors and job satisfaction was significant. The implications of these findings for both research and practice are discussed.

• 한국생물정보학회:학술대회논문집
• /
• 한국생물정보시스템생물학회 2004년도 The 3rd Annual Conference for The Korean Society for Bioinformatics Association of Asian Societies for Bioinformatics 2004 Symposium
• /
• pp.124-130
• /
• 2004

Microarray expression datasets are incessantly cumulated with the aid of recent technological advances. One of the first steps for analyzing these data under various experimental conditions is determining differentially expressed genes (DEGs) in each condition. Reasonable choices of thresholds for determining differentially expressed genes are used for the next -step-analysis with suitable statistical significances. We present a model for identifying DEGs using pathway information based on the global connectivity structure. Pathway information can be regarded as a collection of biological knowledge, thus we are tying to determine the optimal threshold so that the consequential connectivity structure can be the most compatible with the existing pathway information. The significant feature of our model is that it uses established knowledge as a reference to determine the direction of analyzing microarray dataset. In the most of previous work, only intrinsic information in the miroarray is used for the identifying DEGs. We hope that our proposed method could contribute to construct biologically meaningful network structure from microarray datasets.

• 한국IT서비스학회지
• /
• 제15권4호
• /
• pp.125-151
• /
• 2016

In recent years, O2O (Online to Offline) services get a lot of attention to improve the trust in online shopping and minimize the inconvenience and the cost burden in offline shopping as the number of consumers, who do not show concern about the purchase platform like online or offline, increases. Even though the services have been getting the spotlight as a strong business platform for next generation commerce, there have been only a few studies on the O2O services. The purpose of this research is to investigate the factors which affect the consumer's intention to use location-based O2O services. The study is based on VAM (Value-based Adoption Model) which is able to analyze those factors from the aspects of benefit and sacrifice. We used the partial least squares (PLS) method for empirical analysis, and the result shows that contextual offers, instant connectivity, webrooming and economic efficiency, which fall under the benefit, affect perceived value positively while annoyance and face consciousness, which fall under the sacrifice, do not affect perceived value significantly. In addition, contextual offers and instant connectivity affect trust positively. Location accuracy, which falls under the benefit of location-based O2O service, do not significantly affect perceived value and trust while security risk affects trust and use intention negatively. It appears that trust affects perceived value and use intention positively.

• Communications for Statistical Applications and Methods
• /
• 제27권6호
• /
• pp.603-624
• /
• 2020

There is an emerging interest in brain functional connectivity (FC) based on functional Magnetic Resonance Imaging in Alzheimer's disease (AD) studies. The complex and high-dimensional structure of FC makes it challenging to explore the association between altered connectivity and AD susceptibility. We develop a pipeline to refine FC as proper covariates in a penalized logistic regression model and classify normal and AD susceptible groups. Three different quantification methods are proposed for FC refinement. One of the methods is dimension reduction based on common component analysis (CCA), which is employed to address the limitations of the other methods. We applied the proposed pipeline to the Alzheimer's Disease Neuroimaging Initiative (ADNI) data and deduced pathogenic FC biomarkers associated with AD susceptibility. The refined FC biomarkers were related to brain regions for cognition, stimuli processing, and sensorimotor skills. We also demonstrated that a model using CCA performed better than others in terms of classification performance and goodness-of-fit.

• 지식경영연구
• /
• 제12권2호
• /
• pp.56-68
• /
• 2011

The rapid changes in business environments are also applicable to the delivery service field. Numerous companies are using smart phones in order to perform work of the delivery service field that is rapidly developing every year. Smart phones established ubiquitous work environments where access to the server of the head office is possible through telephones, scanners, and the internet anywhere and anytime. However, although smart appliances including smart phones have been diffused, empirical analysis of use of them in actual has not been attempted much. In this regard, current study empirically analyzes how connectivity and context-awareness function of smart phones based on the TAM(Technology Acceptance Model) influence the continuous intention to use through trust, usefulness, and ease of use. The results indicate that the connectivity and context-awareness function, which are natures of smart phones, had impacts on the ease of use and trust, but not on the usefulness. Based on these results, this study suggests implications and future research directions regarding the planning and realization of smart appliances.

• ETRI Journal
• /
• 제39권5호
• /
• pp.729-736
• /
• 2017

This work investigates secure cluster-aided multi-hop randomize-and-forward networks. We present a hop-by-hop multi-hop transmission scheme with relay selection, which evaluates for each cluster the relays that can securely receive the message. We propose an analytical model to derive the secure connectivity probability (SCP) of the hop-by-hop transmission scheme. For comparison, we also analyze SCPs of traditional end-to-end transmission schemes with two relay-selection policies. We perform simulations, and our analytical results verify that the proposed hop-by-hop scheme is superior to end-to-end schemes, especially with a large number of hops or high eavesdropper channel quality. Numerical results also show that the proposed hop-by-hop scheme achieves near-optimal performance in terms of the SCP.

• Communications for Statistical Applications and Methods
• /
• 제30권6호
• /
• pp.561-575
• /
• 2023

Brain network analysis has attracted the interest of neuroscience researchers in studying brain diseases. Magnetoencephalography (MEG) is especially proper for analyzing functional connectivity due to high temporal and spatial resolution. The application of graph theory for functional connectivity analysis has been studied widely, but research on network modeling for MEG still needs more. Temporal exponential random graph model (TERGM) considers temporal dependencies of networks. We performed the brain network analysis, including static/temporal network statistics, on two groups of epilepsy patients who removed the left (LT) or right (RT) part of the brain and healthy controls. We investigate network differences using Multiset canonical correlation analysis (MCCA) and TERGM between epilepsy patients and healthy controls (HC). The brain network of healthy controls had fewer temporal changes than patient groups. As a result of TERGM, on the simulation networks, LT and RT had less stable state than HC in the network connectivity structure. HC had a stable state of the brain network.

• Asia pacific journal of information systems
• /
• 제33권3호
• /
• pp.831-862
• /
• 2023

The rapid adoption of smartphones and tablets among employees has recently forced organizations to proactively embrace bring your own device (BYOD). The situation of COVID-19 makes the concept of BYOD even paramount. Allowing employees to bring their own mobile devices to the workplace has helped companies realize productivity gains and cost benefits. However, BYOD has also blurred the boundaries between work and personal life, thereby creating a stressful environment for employees (Doargajudbur and Hosanoo, 2023). This study explores the relationships between several BYOD attributes and investigates the effects of these attributes on work-to-life conflict. It contributes by introducing workplace connectivity after hours as a new dimension of BYOD attribute to influence work-to-life conflict. Based on boundary theory, a theoretical model is developed and tested with an online survey. The results reveal that flexibility and workplace connectivity after hours positively influence productivity, and flexibility helps to relieve instead of increase work overload. Meanwhile, a higher level of flexibility and productivity can help reduce work-to-life conflict, and a higher level of work overload induces a higher level of work-to-life conflict.

• 한국환경복원기술학회지
• /
• 제20권1호
• /
• pp.131-142
• /
• 2017

The function of urban parks as wildlife habitats is becoming increasingly important. The urban park serves as a key area for preserving urban biodiversity. The purpose of this study is to estimate the bird species diversity in 30 parks in Cheonan city and quantitatively analyze the influence of vegetation, park structure and landscape connectivity index. As the results, a total of 27 birds species and 1,509 individuals were found at the sites and the largest number of birds were found in the Cheongsa park with 17 species. The optimal regression model was selected as the explanatory variables for the logged park area (LPA), the tree cover ratio (Co_T) and the patch betweenness centrality (PB). LPA and Co_T mean the internal characteristics of the park, and PB was the external environmental variable meaning landscape connectivity. LPA was the most important factor (73.3%) as bird habitat, and the PB could be interpreted as a factor that should be considered as important (26.7%). It will be possible to consider these environmental variables in the park and green area construction and management.