• Title/Summary/Keyword: joint efficiency

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Content-Aware D2D Caching for Reducing Visiting Latency in Virtualized Cellular Networks

  • Sun, Guolin;Al-Ward, Hisham;Boateng, Gordon Owusu;Jiang, Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.2
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    • pp.514-535
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    • 2019
  • Information-centric networks operate under the assumption that all network components have built-in caching capabilities. Integrating the caching strategies of information centric networking (ICN) with wireless virtualization improves the gain of virtual infrastructure content caching. In this paper, we propose a framework for software-defined information centric virtualized wireless device-to-device (D2D) networks. Enabling D2D communications in virtualized ICN increases the spectral efficiency due to reuse and proximity gains while the software-defined network (SDN) as a platform also simplifies the computational overhead. In this framework, we propose a joint virtual resource and cache allocation solution for latency-sensitive applications in the next-generation cellular networks. As the formulated problem is NP-hard, we design low-complexity heuristic algorithms which are intuitive and efficient. In our proposed framework, different services can share a pool of infrastructure items. We evaluate our proposed framework and algorithm through extensive simulations. The results demonstrate significant improvements in terms of visiting latency, end user QoE, InP resource utilization and MVNO utility gain.

Studies on vibration control effects of a semi-active impact damper for seismically excited nonlinear building

  • Lu, Zheng;Zhang, Hengrui;Masri, Sami F.
    • Smart Structures and Systems
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    • v.24 no.1
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    • pp.95-110
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    • 2019
  • The semi-active impact damper (SAID) is proposed to improve the damping efficiency of traditional passive impact dampers. In order to investigate its damping mechanism and vibration control effects on realistic engineering structures, a 20-story nonlinear benchmark building is used as the main structure. The studies on system parameters, including the mass ratio, damping ratio, rigid coefficient, and the intensity of excitation are carried out, and their effects both on linear and nonlinear indexes are evaluated. The damping mechanism is herein further investigated and some suggestions for the design in high-rise buildings are also proposed. To validate the superiority of SAID, an optimal passive particle impact damper ($PID_{opt}$) is also investigated as a control group, in which the parameters of the SAID remain the same, and the optimal parameters of the $PID_{opt}$ are designed by differential evolution algorithm based on a reduced-order model. The numerical simulation shows that the SAID has better control effects than that of the optimized passive particle impact damper, not only for linear indexes (e.g., root mean square response), but also for nonlinear indexes (e.g., component energy consumption and hinge joint curvature).

A Study on the Use of Results and Measurement Case of Productivity of the Public Organization (공공조직 생산성 측정사례 및 결과 활용에 관한 연구 : 지방자치단체 생산성지수 중심)

  • Kim, Wan Pyong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.4
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    • pp.225-236
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    • 2014
  • Productivity of public organizations was far older due to issue more difficult to measure than private organizations. Unlike the private sector, the public sector is a diverse and sometimes conflicting objectives (efficiency, effectiveness, equity, democracy, etc.) exist, it is difficult to measure productivity in a single index. Many departments of government is intricately interrelated and sometimes produced by the joint efforts, it is difficult to allocate performance, incentives and accountability to among departments. And there is the difficulty of collecting data on the productivity indicators of public organizations. Despite these difficulties, we developed a productivity index system and measuring method to systematically introduce the concept of productivity in the local administration. In this paper, the productivity and the productivity index measurement practices of local governments conducted annually from 2011 on was deep into research. First, the report found examples of the governments of the developed countries, productivity measurement, then the way MOPAS(Ministry of Public Administration and Security) measure productivity index of local governments, success factors, the implications were in-depth analysis. Finally, in order to enhance productivity and competitiveness municipalities studied ways to take advantage of the productivity index.

A Study on the Differences in the Cognition of the Visitor-Reservation System: Focused on Uiryeong-Gil Area in Bukhansan National Park

  • Sim, Kyu-won;Choe, Yunseon;Jang, Jin;Nam, Seungmin
    • Journal of Forest and Environmental Science
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    • v.37 no.1
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    • pp.69-78
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    • 2021
  • This study aims to verify a difference between the years 2014 and 2019 of Uiryeong-Gil, which is operated by the Visitor-Reservation System, in terms of the cognition of system, operational effectiveness, and behavioral intention. The analysis is as follows. First, among the overall cognition of the Visitor-Reservation System, the satisfaction from - prevention for safety for accident, expansion to other parks, number of visitor restriction, and satisfaction with reservation method - increased compared to 2014. Second, among the effects of the Visitor-Reservation System operation, satisfaction shows differences in year-to-year levels in terms of resource protection, resource damage mitigation efficiency, natural experience opportunity, comfort of visit-environment, and prevention of illegal activities. Third, the analysis of the differences in the behavior of the Visitor-Reservation System showed that the satisfaction of visitors, revisit intention, and overall satisfaction differed per year. The results of this study are meaningful in that the Visitor-Reservation System is no longer the restriction, but the change in cognition for the protection of ecosystems and sustainable visiting in order to expand the Visitor-Reservation System into a sustainable policy.

Axial impact behavior of confined concrete filled square steel tubes using fiber reinforced polymer

  • Zhang, Yitian;Shan, Bo;Kang, Thomas H.K.;Xiao, Yan
    • Steel and Composite Structures
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    • v.38 no.2
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    • pp.165-176
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    • 2021
  • Existing research on confined concrete filled steel tubular (CCFT) columns has been mainly focused on static or cyclic loading. In this paper, square section CCFT and CFT columns were tested under both static and impact loading, using a 10,000 kN capacity compression test machine and a drop weight testing equipment. Research parameters included bonded and unbonded fiber reinforced polymer (FRP) wraps, with carbon, basalt and glass FRPs (or CFRP, BFRP, and GFRP), respectively. Time history curves for impact force and steel strain observed are discussed in detail. Experimental results show that the failure modes of specimens under impact testing were characterized by local buckling of the steel tube and cracking at the corners, for both CCFT and CFT columns, similar to those under static loading. For both static and impact loading, the FRP wraps could improve the behavior and increase the loading capacity. To analyze the dynamic behavior of the composite columns, a finite element, FE, model was established in LS-DYNA. A simplified method that is compared favorably with test results is also proposed to predict the impact load capacity of square CCFT columns.

Effect of Wearing a Thermal Compression Sleeve on Isokinetic Strength and Muscle Activity of Wrist Flexors and Extensors

  • Kim, Ki Hong;Jeong, Hwan Jong;Hong, Chan Jeong;Kim, Hyun Sung;Kim, Byung Kwan
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.2
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    • pp.183-191
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    • 2022
  • The purpose of this study, the wearing conditions of functional pressure clothing applied with the thermotherapy device were determined by three types (NW, CW, TCW) and the difference in isokinetic strength, muscle activity around the forearm was investigated and the effects of products mixed with thermotherapy and pressure treatment were verified. Ten men in their 20s were selected as subjects, and all subjects were randomly assigned three wearing conditions, and wrist flexion/extension exercise was performed at 30° and 90° angular velocity in isokinetic equipment. Peak torque, average power, and EMG were measured during exercise in all conditions. For peak torque, CW was significantly highest at velocity of 30°/sec flexion. Average power showed no significant difference by condition. In the angular velocity of 90°/sec, flexion was significantly higher in CW and TCW than in NW. As a result, wearing clothes with pressure effect and heat effect can show high efficiency in high muscle strength development and fast contraction activity during low speed exercise, and it is thought that it can show improvement of exercise ability through efficient recruitment of motor unit.

The Effect of Bank Liquidity on Bank's Stability in the Presence of Managerial Optimism

  • HABIB, Ashfaq;KHAN, Muhammad Asif;MEYER, Natanya
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.8
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    • pp.183-196
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    • 2022
  • Bank stability serves as a prerequisite for the smooth functioning of economic and financial activities in the country. Banks face numerous risks, and liquidity plays an essential role in determining a bank's long-term growth and financial stability. By using the sample of 70 banks of the Gulf Cooperation Council, this study examines the association between funding the liquidity and the creation of liquidity and their impact on bank stability. Firstly, the reciprocal relationship reveals between funding the liquidity and the creation of liquidity by employing the 2SLS regression model. Further, by employing the dynamic GMM model, the research finds that funding liquidity is significant and positively influences bank stability. However, bank stability is significantly negatively influenced by the creation of liquidity, but the combined effect of funding the liquidity and creation of liquidity positively explains the bank stability. Additionally, this study reveals that managerial optimism biases contribute to determining the bank's liquidity and long-term stability. The finding of this study supports the executives, policymakers, and management of banks in understating liquidity risks, efficiency, and bank stability. The findings support regulatory guidelines mainly by the Basel III framework, which places more importance on the joint management of funding the liquidity and creation of liquidity in the economy.

Role of A-TIG process in joining of martensitic and austenitic steels for ultra-supercritical power plants -a state of the art review

  • Bhanu, Vishwa;Gupta, Ankur;Pandey, Chandan
    • Nuclear Engineering and Technology
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    • v.54 no.8
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    • pp.2755-2770
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    • 2022
  • The need for Dissimilar Welded Joint (DWJ) in the power plant components arises in order to increase the overall efficiency of the plant and to avoid premature failure in the component welds. The Activated-Tungsten Inert Gas (A-TIG) welding process, which is a variant of Tungsten Inert Gas (TIG) welding, is focus of this review work concerning the DWJ of nuclear grade creep-strength enhanced ferritic/martensitic (CSEF/M) steels and austenitic steels. A-TIG DWJs are compared with Multipass-Tungsten Inert Gas (M-TIG) DWJ based on their mechanical and microstructural properties. The limitations of multipass welding have put A-TIG welding in focus as A-TIG provides a weld with increased depth of penetration (DOP) and enhanced mechanical properties. Hence, this review article covers the A-TIG welding principle and working parameters along with detailed analysis of role played by the flux in welding procedure. Further, weld characteristics of martensitic and austenitic steel DWJ developed with the A-TIG welding process and the M-TIG welding process are compared in this study as there are differences in mechanical, microstructural, creep-related, and residual stress obtained in both TIG variants. The mechanics involved in the welding process is deliberated which is revealed by microstructural changes and behavior of base metals and WFZ.

Optimizing Energy-Latency Tradeoff for Computation Offloading in SDIN-Enabled MEC-based IIoT

  • Zhang, Xinchang;Xia, Changsen;Ma, Tinghuai;Zhang, Lejun;Jin, Zilong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.12
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    • pp.4081-4098
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    • 2022
  • With the aim of tackling the contradiction between computation intensive industrial applications and resource-weak Edge Devices (EDs) in Industrial Internet of Things (IIoT), a novel computation task offloading scheme in SDIN-enabled MEC based IIoT is proposed in this paper. With the aim of reducing the task accomplished latency and energy consumption of EDs, a joint optimization method is proposed for optimizing the local CPU-cycle frequency, offloading decision, and wireless and computation resources allocation jointly. Based on the optimization, the task offloading problem is formulated into a Mixed Integer Nonlinear Programming (MINLP) problem which is a large-scale NP-hard problem. In order to solve this problem in an accessible time complexity, a sub-optimal algorithm GPCOA, which is based on hybrid evolutionary computation, is proposed. Outcomes of emulation revel that the proposed method outperforms other baseline methods, and the optimization result shows that the latency-related weight is efficient for reducing the task execution delay and improving the energy efficiency.

Bird's Eye View Semantic Segmentation based on Improved Transformer for Automatic Annotation

  • Tianjiao Liang;Weiguo Pan;Hong Bao;Xinyue Fan;Han Li
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.8
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    • pp.1996-2015
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    • 2023
  • High-definition (HD) maps can provide precise road information that enables an autonomous driving system to effectively navigate a vehicle. Recent research has focused on leveraging semantic segmentation to achieve automatic annotation of HD maps. However, the existing methods suffer from low recognition accuracy in automatic driving scenarios, leading to inefficient annotation processes. In this paper, we propose a novel semantic segmentation method for automatic HD map annotation. Our approach introduces a new encoder, known as the convolutional transformer hybrid encoder, to enhance the model's feature extraction capabilities. Additionally, we propose a multi-level fusion module that enables the model to aggregate different levels of detail and semantic information. Furthermore, we present a novel decoupled boundary joint decoder to improve the model's ability to handle the boundary between categories. To evaluate our method, we conducted experiments using the Bird's Eye View point cloud images dataset and Cityscapes dataset. Comparative analysis against stateof-the-art methods demonstrates that our model achieves the highest performance. Specifically, our model achieves an mIoU of 56.26%, surpassing the results of SegFormer with an mIoU of 1.47%. This innovative promises to significantly enhance the efficiency of HD map automatic annotation.