• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2338-2356
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• 2019

Vehicular ad-hoc network (VANET) is the name of technology, which uses 'mobile internet' to facilitate communication between vehicles. The aim is to ensure road safety and achieve secure communication. Therefore, the reliability of this type of networks is a serious concern. The reliability of VANET is dependent upon proper communication between vehicles within a given amount of time. Therefore a new formula is introduced, the terms of the new formula correspond 1 by 1 to a class special ST route (SRORT). The new formula terms are much lesser than the Inclusion-Exclusion principle. An algorithm for the Source-to-Terminal reliability was presented, the algorithm produced Source-to-Terminal reliability or computed a Source-to-Terminal reliability expression by calculating a class of special networks of the given network. Since the architecture of this class of networks which need to be computed was comparatively trivial, the performance of the new algorithm was superior to the Inclusion-Exclusion principle. Also, we introduce a mobility metric called universal speed factor (USF) which is the extension of the existing speed factor, that suppose same speed of all vehicles at every time. The USF describes an exact relation between the relative speed of consecutive vehicles and the headway distance. The connectivity of vehicles in different mobile situations is analyzed using USF i.e., slow mobility connectivity, static connectivity, and high mobility connectivity. It is observed that $p_c$ probability of connectivity is directly proportional to the mean speed ${\mu}_{\nu}$ till specified threshold ${\mu}_{\tau}$, and decreases after ${\mu}_{\tau}$. Finally, the congested network is connected strongly as compared to the sparse network as shown in the simulation results.

• Asia Pacific Journal of Business Review
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• 제1권1호
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• pp.67-88
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• 2016

This study aims to help address concerns about the growing demand of wider bandwidth Internet connection in the Philippines. Using articles and research of international organizations and content from official websites of the Philippine government, this paper has carefully examined the slow Internet connectivity and the high cost that the end-users pay for it. This paper suggests that this inefficiency hampers the motivation of users to innovate in a way that could contribute to inclusive growth and the development of an inclusive information society. Through a comparison of the current global ICT situation with the current situation in the Philippines, this paper shows that the country's Internet infrastructure lags behind among those of contemporary developing countries in Asia, particularly in terms of Internet connectivity. In 2015, Thailand had an average Internet speed of 7.4 Mbps, Sri Lanka 7.4, and Malaysia 4.3. Meanwhile, the Philippines had a meager average Internet speed of 2.8 Mbps, placing the country at 104 among 160 countries, with developed countries in Asia such as South Korea (23.6 Mbps) and Singapore (12.9 Mbps) ranking 1 and 12, respectively. Findings show that the lack of competition in the Internet connectivity market, among other reasons, is at the root of the dilemma of slow and costly Internet connection. Assessing the accomplishments of the Republic of Korea and other broadband-leading countries has provided practical insights and recommendations that can promote competitiveness. Furthermore, related literature argues how ISP practices may affect Internet speed and cost. This study offers an approach in improving Internet connectivity in the Philippines by bridging the gap between the Internet infrastructure market and government policies.

• 전기학회논문지
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• 제57권4호
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• pp.715-717
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• 2008

The connectivity weighted Hough transform is a useful method for detecting well-connected short lines without generating false lines yet requires extensive computation. This letter describes a method that reduces the computation of the connectivity weighted Hough transform by removing unnecessary weight calculations using the gradient angles of feature points. In simulations with synthetic images and experiments with liquid crystal display panel images, the proposed method showed significantly improved speed without compromising detectability.

• 한국철도학회논문집
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• 제17권1호
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• pp.59-69
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• 2014

국가 전체의 지속가능한 교통체계 확립을 위한 연계교통체계의 구축이 중요한 교통정책으로 대두되고 있고 철도 및 대중교통은 통행의 완결성 부족으로 인해 수단간 연계성을 고려하는 것이 필수적이라 할 수 있다. 특히, 고속철도는 우리나라 교통체계의 획기적 변화를 가져왔고 고속철도역은 다양한 수단이 연계되어야 하는 중요한 교통 결절점으로 수단간 연계교통망 차원에서 분석이 필요하다. 이에 본 연구는 고속철도역의 연계교통망 차원에서 고속철도와 연계교통수단의 연계기능을 객관적이고 정량적으로 분석하기 위한 새로운 연계성 분석 기법을 제시하였다. 서울역, 부산역, 울산역, 신경주역을 공간적 범위로 설정하였고 고속철도 역사내의 내부환승 시설을 제외한 고속철도역과 영향권내 기 종점간을 연결하는 연계교통수단의 세부 연계기능 지표를 조사 분석하였다. 구축된 자료를 이용하여 구조방정식 모형을 적용한 연계성 분석 기법을 제시하고 연계성 지표를 개발하였다.

• Ecology and Resilient Infrastructure
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• 제7권4호
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• pp.320-326
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• 2020

본 연구는 횡단구조물에서의 어류의 이동 특성에 따른 종적 연결성을 평가하였다. 대상 구간은 원주천이며, 대상 어종은 피라미와 잡고기를 대상으로 하였다. 흐름 분석은 HEC-RAS 모형을 사용하였으며, 종적 연결성 분석은 ICE 방법을 적용하였다. 종적 연결성을 분석하기 위하여 수리분석 결과물 중 횡단구조물 상·하류 수위차, 유속, 하류단 웅덩이 깊이에 따른 대상 어종의 유영 속도를 적용하였다. 그 결과 피라미의 경우 종적 연결성이 약 76점, 잡고기의 경우 종적 연결성이 약 23점으로 나타났다.

• International Journal of Advanced Culture Technology
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• 제11권1호
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• pp.395-402
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• 2023

The implementation of a hybrid network utilizing Power Line Communication (PLC) and Wi-Fi technologies has been demonstrated to improve signal strength and coverage in areas with poor connectivity due to internet shadow areas. In this study we strategically positioned Wi-Fi relays and utilized the capabilities of PLC technology to significantly improve signal strength and coverage in areas with poor connectivity. We also analyzed the effects of metallic obstacles on Wi-Fi signal propagation and proposed a solution to strengthen the signal enough to pass through them. Our experiment demonstrated the feasibility and potential of using this hybrid network in industrial scenarios for real-time data transmission. Overall, the results suggest that the use of PLC and Wi-Fi hybrid networks can be a cost-effective and efficient solution for overcoming internet connectivity challenges and has the potential to provide high-speed internet access to areas with unreliable signals.

• 대한교통학회지
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• 제28권4호
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• pp.129-139
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• 2010

본 연구에서는 도로 네트워크에서 노드의 연계성 평가 모형을 제시하였다. 우선 두 노드 간의 경로 수, 경로의 굴곡도, 설계속도 및 용량을 고려하여 노드 간 연계성 지수를 정의하였다. 노드의 연계성은 그 노드와 타 대상 노드들 간의 연계성 지수의 가중 평균으로 산출되는데, 여기서 대상 노드들과의 연결 가중치는 통행수요와 거리에 의해 결정된다. 본 연구에서 개발한 연계성 평가 모형을 가상 가로망에 적용한 결과 모형이 적용 가능하고 적정한 결과를 산출하는 것을 확인할 수 있었다. 본 연구의 연계성 평가 모형은 통행 단위를 통일시키고 철도 링크의 용량 산정 문제를 해결하면 철도 네트워크를 포함하는 통합 교통 네트워크의 연계성 분석에도 활용될 수 있다.

• 전기학회논문지
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• 제56권1호
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• pp.197-205
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• 2007

We have proposed a novel line detection method based on the estimated probability density function of gradient directions of edges. By estimating peaks of the density function, we determine groups of edges that have the same gradient direction. For edges in the same groups, we detect lines that correspond to peaks of the connectivity weighted distribution of the distances from the origin. In the experiments using the Data Matrix barcode images and LCD images, the proposed method showed better performance than conventional Methods in terms of the processing speed and accuracy.

• 대한교통학회지
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• 제28권3호
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• pp.85-98
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• 2010

대중교통 네트워크가 점점 더 복합수단화됨에 따라 네트워크의 연계성이 중요한 개념으로 대두되고 있다. 본 연구에서는 복합수단 대중교통 네트워크의 연계성을 평가하는 계량모형을 제시하였다. 이를 위하여 우선 대중교통 노선의 평가지표로 노선연장, 수송용량, 통행속도를 선정하고 이들의 곱을 노선의 연계강도로 정의하였다. 또한 사회 네트워크 분석에서 사용되는 노드의 중심성 지표 중 하나인 degree centrality 개념을 대중교통 네트워크에 적합하게 수정하였다. 노선의 연계강도와 그 노선이 서비스하는 정류장의 degree centrality를 접목하여 정류장의 연계정도를 나타내는 지수를 개발하였다. 이를 토대로 복합수단 대중교통 네트워크 내의 노선 및 지역의 연계성 지수도 도출하였다. 또한 정류장의 연계성 지수와 이용자수용비율 함수를 이용하여 환승센터의 연계성을 평가하는 방법도 제시하였다. 사례연구 결과 본 연구에서 개발된 연계성 평가 모형은 복합수단 대중교통 네트워크의 특성을 제대로 반영하고 있으며, 대중교통 네트워크 내의 정류장, 노선, 지역의 연계성을 적절하게 평가할 수 있고, 또한 환승센터의 서비스수준 산정에 활용될 수 있음을 확인하였다.

• 한국식품영양학회지
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• 제29권6호
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• pp.1050-1057
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• 2016

SNS (Social network service) characteristics are perceived to simplify use. We carried out empirical studies on these parameters to observe the impact on the image of catering SNS online by word-of-mouth. The subjects of the study were as follows: 32.3% (392 persons) 19 years old, 67.7% (821 persons) over 19 years, 51.0% (619 persons) in their 20s, 22.1% (268 persons) in their 30s, 17.6% in their 50s, and 9.3% (112 persons) over 50 years. After verifying the hypothesis proposed that SNS characteristics perceived the ease of use, the significant factor identified in usability were connectivity Speed (${\beta}=0.213$), playfulness (${\beta}=0.246$), information (${\beta}=0.115$), and reciprocity (${\beta}=0.357$). Dual reciprocity had the most impact. It was observed that a longer impact of these significant factors improved the feel and fun of use. If SNS companies cater to, quick and easy, diverse, reliable and latest information, they can increase the ease of use, and availability, depending on the goals. Also, significant factors in the SNS features and online word of mouth was playfulness (${\beta}=0.312$), information (${\beta}=0.207$), reciprocity (${\beta}=0.066$) and perceived ease of use, and usefulness (${\beta}=0.293$), double playfulness had the maximum impact. These features provided more fun, reliable information, and could quickly deliver the latest information. The more the perceived usefulness, and ease of use, higher was the online word-of-mouth effect. SNS usage characteristics of connectivity Speed did not show any statistical significance in online word-of-mouth. Thus, catering businesses need to find ways to increase the ease of use, make the usefulness multifaceted, constantly checking the catering information on the SNS and ensuring to get the latest information is from diverse and reliable sources. This would increase the fun for the customer making the SNS to actively be utilized as a marketing tool.