Green Cellular Networks: A Survey, Some Research Issues and Challenges

Energy efficiency in cellular networks is a growing concern for cellular operators to not only maintain profitability, but also to reduce the overall environment effects. This emerging trend of achieving energy efficiency in cellular networks is motivating the standardization authorities and network operators to continuously explore future technologies in order to bring improvements in the entire network infrastructure. In this article, we present a brief survey of methods to improve the power efficiency of cellular networks, explore some research issues and challenges and suggest some techniques to enable an energy efficient or "green" cellular network. Since base stations consume a maximum portion of the total energy used in a cellular system, we will first provide a comprehensive survey on techniques to obtain energy savings in base stations. Next, we discuss how heterogeneous network deployment based on micro, pico and femto-cells can be used to achieve this goal. Since cognitive radio and cooperative relaying are undisputed future technologies in this regard, we propose a research vision to make these technologies more energy efficient. Lastly, we explore some broader perspectives in realizing a "green" cellular network technologyComment: 16 pages, 5 figures, 2 table

The role of supply chain integration in achieving competitive advantage: A study of UK automobile manufacturers

The competitive nature of the global automobile industry has resulted in a battle for efficiency and consistency in supply chain management (SCM). For manufacturers, the diversified network of suppliers represents more than just a production system; it is a strategic asset that must be managed, evaluated, and revised in order to attain competitive advantage. One capability that has become an increasingly essential means of alignment and assessment is supply chain integration (SCI). Through such practices, manufacturers create informational capital that is inimitable, yet transferrable, allowing suppliers to participate in a mutually-beneficial system of performance-centred outcomes. From cost reduction to time improvements to quality control, the benefits of SCI extend throughout the supply chain lifecycle, providing firms with improved predictability, flexibility, and responsiveness. Yet in spite of such benefits, key limitations including exposure to risks, supplier failures, or changing competitive conditions may expose manufacturers to a vulnerable position that can severely impact value and performance. The current study summarizes the perspectives and predictions of managers within the automobile industry in the UK, highlighting a dynamic model of interdependency and interpolation that embraces SCI as a strategic resource. Full commitment to integration is critical to achieving improved outcomes and performance; therefore, firms seeking to integrate throughout their extended supply chain must be willing to embrace a less centralized locus of control

On-Disk Data Processing: Issues and Future Directions

In this paper, we present a survey of "on-disk" data processing (ODDP). ODDP, which is a form of near-data processing, refers to the computing arrangement where the secondary storage drives have the data processing capability. Proposed ODDP schemes vary widely in terms of the data processing capability, target applications, architecture and the kind of storage drive employed. Some ODDP schemes provide only a specific but heavily used operation like sort whereas some provide a full range of operations. Recently, with the advent of Solid State Drives, powerful and extensive ODDP solutions have been proposed. In this paper, we present a thorough review of architectures developed for different on-disk processing approaches along with current and future challenges and also identify the future directions which ODDP can take.Comment: 24 pages, 17 Figures, 3 Table

The State of the Art of Information Integration in Space Applications

This paper aims to present a comprehensive survey on information integration (II) in space informatics. With an ever-increasing scale and dynamics of complex space systems, II has become essential in dealing with the complexity, changes, dynamics, and uncertainties of space systems. The applications of space II (SII) require addressing some distinctive functional requirements (FRs) of heterogeneity, networking, communication, security, latency, and resilience; while limited works are available to examine recent advances of SII thoroughly. This survey helps to gain the understanding of the state of the art of SII in sense that (1) technical drivers for SII are discussed and classified; (2) existing works in space system development are analyzed in terms of their contributions to space economy, divisions, activities, and missions; (3) enabling space information technologies are explored at aspects of sensing, communication, networking, data analysis, and system integration; (4) the importance of first-time right (FTR) for implementation of a space system is emphasized, the limitations of digital twin (DT-I) as technological enablers are discussed, and a concept digital-triad (DT-II) is introduced as an information platform to overcome these limitations with a list of fundamental design principles; (5) the research challenges and opportunities are discussed to promote SII and advance space informatics in future

A Building Information Modeling (BIM)-centric Digital Ecosystem for Smart Airport Life Cycle Management

An increasing number of new airport infrastructure construction and improvement projects are being delivered in today\u27s modern world. However, value creation is a recurring issue due to inefficiencies in managing capital expenditures (CapEx) and operating expenses (OpEx), while trying to optimize project constraints of scope, time, cost, quality, and resources. In this new era of smart infrastructure, digitalization transforms the way projects are planned and delivered. Building Information Modeling (BIM) is a key digital process technique that has become an imperative for today\u27s Architecture, Engineering, Construction and Operations (AECO) sector. This research suggests a BIM-centric digital ecosystem by detailing technical and strategic aspects of Airport BIM implementation and digital technology integration from a life cycle perspective. This research provides a novel approach for consistent and continuous use of digital information between business and functional levels of an airport by developing a digital platform solution that will enable seamless flow of information across functions. Accordingly, this study targets to achieve three objectives: 1- To provide a scalable know-how of BIM-enabled digital transformation; 2- To guide airport owners and major stakeholders towards converging information siloes for airport life cycle data management by an Airport BIM Framework; 3- To develop a BIM-based digital platform architecture towards realization of an airport digital twin for airport infrastructure life cycle management. Airport infrastructures can be considered as a System of Systems (SoS). As such, Model Based Systems Engineering (MBSE) with Systems Modeling Language (SysML) is selected as the key methodology towards designing a digital ecosystem. Applying MBSE principles leads to forming an integrating framework for managing the digital ecosystem. Furthermore, this research adopts convergent parallel mixed methods to collect and analyze multiple forms of data. Data collection tools include extensive literature and industry review; an online questionnaire; semi-structured interviews with airport owner parties; focus group discussions; first-hand observations; and document reviews. Data analysis stage includes multiple explanatory case study analyses, thematic analysis, project mapping, percent coverage analysis for coded themes to achieve Objective 1; thematic analysis, cluster analysis, framework analysis, and non-parametric statistical analysis for Objective 2; and qualitative content analysis, non-parametric statistical analysis to accomplish Objective 3. This research presents a novel roadmap toward facilitation of smart airports with alignment and integration of disruptive technologies with business and operational aspects of airports. Multiple comprehensive case study analyses on international large-hub airports and triangulation of organization-level and project-level results systematically generate scalable technical and strategic guidelines for BIM implementation. The proposed platform architecture will incentivize major stakeholders for value-creation, data sharing, and control throughout a project life cycle. Introducing scalability and minimizing complexity for end-users through a digital platform approach will lead to a more connected environment. Consequently, a digital ecosystem enables sophisticated interaction between people, places, and assets. Model-driven approach provides an effective strategy for enhanced decision-making that helps optimization of project resources and allows fast adaptation to emerging business and operational demands. Accordingly, airport sustainability measures -economic vitality, operational efficiency, natural resources, and social responsibility- will improve due to higher levels of efficiency in CapEx and OpEx. Changes in business models for large capital investments and introducing sustainability to supply chains are among the anticipated broader impacts of this study

Specification of the PERFoRM architecture for the seamless production system reconfiguration

The world is assisting to the fourth industrial revolution, with several domains of science and technology being strongly developed and, specially, being integrated with each other, allowing to build evolvable complex systems. Data digitization, big-data analysis, distributed control, Industrial Internet of Things, Cyber-Physical Systems and self-organization, amongst others, are playing an important role in this journey. This paper considers the best practices from previous successful European projects addressing distributed control systems to develop an innovative architecture that can be industrially deployed. For this purpose, a particular design process has to be addressed in order to consider the requirements and functionalities from various use cases. To investigate the known practices, four use cases are enlighted in this paper, which cover a wide spectrum of the European industrial force, as well as industrial standards to support a smooth migration from traditional systems to the emergent distributed systems.info:eu-repo/semantics/publishedVersio

A New Framework to Explore the International Vision of College Teacher

Aiming to address the methodology to explore and broaden college teachers’ international vision and horizon for engineering education of college students or engineers, this paper proposed an exploration framework based on Johari Window model. The framework of international vision exploration for teachers includes four zones: open/active vision, called Zone A; hidden/sleeping vision, called Zone B; blind/potential vision, called Zone C; and unknown/darkness vision, called Zone D. The four zones’ characteristics and formation mechanisms were generally analyzed, the corresponding driving forces were then identified in order to help transform teacher international vision within Zones B, C and D into Zone A. To provide the effective and feasible approach, several significant factors including culture tension, original vision conflict and pure curiosity for unknown were then determined in exploring and improving teacher’s international vision in terms of curiosity, inner creativity, potential vision, career development, and worldwide adaptability on engineering education evolution

자율주행을 위한 V2X 기반 차량 CDN 설계

학위논문 (석사) -- 서울대학교 대학원 : 공학전문대학원 응용공학과, 2021. 2. 김성우.Recent technical innovation has driven the evolution of autonomous vehicles. To improve safety as well as on-road vehicular experience, vehicles should be connected with each other or to vehicular networks. Some specification groups, e.g., IEEE and 3GPP, have studied and released vehicular communication requirements and architecture. IEEEs Wireless Access in Vehicular Environment focuses on dedicated and short-range communication, while 3GPPs New radio V2X supports not only sidelink but also uplink communication. The 3GPP Release 16, which supports 5G New Radio, offers evolved functionalities such as network slice, Network Function Virtualization, and Software-Defined Networking. In this study, we define and design a vehicular network architecture compliant with 5G core networks. For localization of autonomous driving vehicles, a high-definition map needs to contain the context of trajectory . We also propose new methods by which autonomous vehicles can push and pull map content efficiently, without causing bottlenecks on the network core. We evaluate the performance of V2X and of the proposed caching policy via network simulations. Experimental results indicate that the proposed method improves the performance of vehicular content delivery in real-world road environments.최근들어 기술의 혁신은 자율주행 자동차의 발전을 가속화 하고 있다. 보다 높은 수준의 자율 주행을 구현하기 위해서, 차량은 네트워크를 통해 서로 연결되어 있어야 하고 차량의 안전과 편의성을 향상 시킬 수 있도록 정보를 공유 할 수 있어야 한다. 표준화 단체인 IEEE와 3GPP는 차량 통신 요구사항, 아키텍처를 연구하고 개정해왔다. IEEE가 전용 채널을 통한 근접 지역 통신에 초점을 맞추는 반면에, 3GPP의 New Radio V2X는 Sidelink 뿐만 아니라 Uplink 통신을 동시에 지원한다. 5G 통신을 지원하는 3GPP Release 16은 Network Slice, NFV, SDN과 같은 새로운 통신 기능들을 제공한다. 이 연구에서는 새롭게 정의된 5G Core Network Architecture를 바탕으로 차량 네트워크를 정의하고 설계하였다. 자율주행 자동차의 측위를 위해서, 고해상도 지도는 각 구성요소들의 의미와 속성을 자세하게 포함하고 있어야 한다. 우리는 이 연구에서 V2X 네트워크 상에 HD map을 중계할 수 있는 Edge Server를 제안 함으로써, 중앙에서 발생할 수 있는 병목현상을 줄이고 전송 Delay를 최소화한다. 또한 Edge의 컨텐츠를 등록하고 삭제하는 정책으로 기존의 LRU, LFU가 아닌 새로운 컨텐츠 교체 알고리즘을 제안하였다. 실제 주행 시험과 시뮬레이션을 통한 실험을 통해 전송 품질을 향상시켰으며, Edge 컨텐츠의 활용도를 높였다.I. Introduction 1 II. Related Works 6 2.1 V2X Standardization 6 2.1.1 IEEE WAVE 6 2.1.2 3GPP C-V2X 9 2.2 Geographic Contents 14 2.3 Vehicular Content Centric Network 17 III. System Modeling 20 3.1 NR-V2X Architecture Analysis 20 3.2 Caching Strategy for HD Map Acquisition 23 IV. Evaluation 30 4.1 Contents Replacement Strategy 30 4.2 V2X Characteristics 36 4.3 Edge Performance in Driving on the Road 38 4.4 Edge Performance on 3D Point Clouds Caching for Localization 44 V. Conclusion 47 Bibliography 49 Abstract 54Maste

CoopDynSim : a 3D robotics simulator

This paper presents CoopDynSim, a multi-robot 3D simulator. The main motivations for the development of a new simulation software lie in the need to emulate specific, custom made sensors, combined with the desire to smoothly transfer controller code from simulation to real implementation. The latter is achieved through the use of the same middleware layer already implemented in the real platforms. The high modularity of the solution allows the user to easily add new components or design new platforms. By having independent simulation threads for each robot, distributed control algorithms can easily be tested, abetted by a socket based connection, granting the possibility for an asynchronous, over the network, controller architecture. The ability to run simulations in real or simulated time, as well as a play back option, represent valuable features of the software. The simulator has been used in several projects, with different platforms and distinct control applications, proving it as a heterogeneous and flexible solution. Furthermore, its usage as a teaching tool in a robotics’ summer school as well as in an introductory robotics class in our university, upholds its simplicity and user-friendliness.Fundação para a Ciência e a Tecnologia (FCT) - ref. SFRH/BD/38885/200