• Title/Summary/Keyword: Energy utilization

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A trust evaluation method for improving nodes utilization for wireless sensor networks

  • Haibo, Shen;Kechen, Zhuang;Hong, Zhang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1113-1135
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    • 2018
  • Existing trust evaluation models for wireless sensor networks can accurately and objectively evaluate trust value of nodes, but the nodes' energy saving problem was ignored. Especially when there are a few malicious nodes in a network, the overall trust value calculation for all nodes would waste lots of energy. Beside that, the network failure caused by nodes death was also not considered. In this paper, we proposed a method for avoiding energy hole which applied trust evaluation models and a trust evaluation method based on information entropy, so as to achieve the purpose of improving nodes utilization. Simulation results show that the proposed method can effectively improve nodes utilization, and it has reasonable detection rate and lower false alert rate compared to other classical methods.

A Basic Study on Energy Saving of University Library - About 'H' University Building located in Sejong City - (대학도서관의 에너지 절감에 관한 기초적 연구 - 세종시에 위치한 H 대학 건물을 중심으로 -)

  • Roh, Ji Woong
    • KIEAE Journal
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    • v.13 no.4
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    • pp.69-74
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    • 2013
  • It is difficult to apply a design standard uniformly to university buildings because various education courses are conducted. However, a design guideline for saving energy is necessary in order to prepare for low-energy days. A library in any university is one of the buildings that a lot of people use and most of the energy is spent. Therefore, the investigation on the energy savings of library facilities is very important and urgent. This study finally presents the design guideline of those facilities for low-energy. In this paper, the trend of space layout, utilization schedule and performance of materials are investigated, and the impact on energy savings and effective energy saving strategies are analyzed and illustrated by energy simulation. As a result of energy analysis from the case of 'H' university, it is confirmed that the utilization schedule effects mostly to energy consumption and the layout and orientation of the rooms in the library are the major parameters. Among the investigated saving strategies, green roofs are found as the most effective part for heating energy savings, and outdoor air cooling is known as the most effective method for cooling energy savings.

Tc and Jc distribution in in situ processed MgB2 bulk superconductors with/without C doping

  • Kim, C.J.;Kim, Y.J.;Lim, C.Y.;Jun, B.H.;Park, S.D.;Choo, K.N.
    • Progress in Superconductivity and Cryogenics
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    • v.16 no.2
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    • pp.36-41
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    • 2014
  • Temperature dependence of magnetic moment (m-T) and the magnetization (M-H) at 5 K and 20 K of the in situ processed $MgB_2$ bulk pellets with/without carbon (C) doping were examined. The superconducting critical temperature ($T_c$), the superconducting transition width (${\delta}T$) and the critical current density ($J_c$) were estimated for ten test samples taken from the $MgB_2$ bulk pellets. The reliable m-T characteristics associated with the uniform $MgB_2$ formation were obtained for both $MgB_2$ pellets. The $T_cs$ and ${\delta}Ts$ of all test samples of the undoped $MgB_2$ were the same each other as 37.5 K and 1.5 K, respectively. The $T_cs$ and ${\delta}Ts$ of the C-doped $MgB_2$ were 36.5 K and 2.5 K, respectively. Unlike the m-T characteristics, there existed the difference among the M-H curves of the test samples, which might be caused by the microstructure variation. In spite of the slight $T_c$ decrease, the C doping was effective in enhancing the $J_c$ at 5 K.

Development of Freeze-Dried DOTMP Kits for Labeling with 68Ga

  • Lim, Jae Cheong;Choi, Sang Mu;Cho, Eun Ha;Lee, So Young;Dho, So Hee;Kim, Soo Yong
    • Journal of Radiation Industry
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    • v.9 no.2
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    • pp.63-68
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    • 2015
  • Lyophilized DOTMP kits were prepared using DOTMP, ammonium acetate, and ascorbic acid. The $^{68}Ga$-DOTMP was prepared by incubating the kit dissolved in 0.5 ml of concentrated $^{68}Ga$ using NaCl method and 0.5 ml of DDW, at $100^{\circ}C$ for 7 min. The labeling yield was evaluated by two solvent systems of TLC. 1 MBq of concentrated $^{68}Ga$ was labeled with $0.8{\mu}g$ of DOTMP by high radiolabeling yield (>98%), which was determined by two TLC methods. The composition of the prepared freeze-dried vial is $400{\mu}g$ of DOTMP, 19.27 mg of ammonium acetate and 17.62 mg of ascorbic acid. ~555 MBq of $^{68}Ga$-DOTMP was prepared with excellent radiochemical purity (>98%) and it was stable for 4 hr at room temperature. In conclusion, Freeze-dried DOTMP kits for the convenient preparation of $^{68}Ga$-DOTMP have been developed. Availability of this kit is expected to stimulate the widespread use of $^{68}Ga$-DOTMP in the fields of nuclear medicine.

Energy and Service Level Agreement Aware Resource Allocation Heuristics for Cloud Data Centers

  • Sutha, K.;Nawaz, G.M.Kadhar
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.11
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    • pp.5357-5381
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    • 2018
  • Cloud computing offers a wide range of on-demand resources over the internet. Utility-based resource allocation in cloud data centers significantly increases the number of cloud users. Heavy usage of cloud data center encounters many problems such as sacrificing system performance, increasing operational cost and high-energy consumption. Therefore, the result of the system damages the environment extremely due to heavy carbon (CO2) emission. However, dynamic allocation of energy-efficient resources in cloud data centers overcomes these problems. In this paper, we have proposed Energy and Service Level Agreement (SLA) Aware Resource Allocation Heuristic Algorithms. These algorithms are essential for reducing power consumption and SLA violation without diminishing the performance and Quality-of-Service (QoS) in cloud data centers. Our proposed model is organized as follows: a) SLA violation detection model is used to prevent Virtual Machines (VMs) from overloaded and underloaded host usage; b) for reducing power consumption of VMs, we have introduced Enhanced minPower and maxUtilization (EMPMU) VM migration policy; and c) efficient utilization of cloud resources and VM placement are achieved using SLA-aware Modified Best Fit Decreasing (MBFD) algorithm. We have validated our test results using CloudSim toolkit 3.0.3. Finally, experimental results have shown better resource utilization, reduced energy consumption and SLA violation in heterogeneous dynamic cloud environment.

The Economic Effects of the Expanding Manufacture and Utilization of Solid Refuse Fuel (SRF) Facilities in Korea : An Input-output Analysis (SRF 제조·활용 시설 확대의 경제적 파급효과 분석)

  • Cho, Yongcheol;Park, Soyeon;Yoo, Seunghoon
    • Journal of Energy Engineering
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    • v.25 no.3
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    • pp.95-103
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    • 2016
  • The government is trying to expanding the manufacture and utilization of solid refuse fuel (SRF) facilities in order to mitigate greenhouse gases reducing and eco-friendly waste-to-energy recovery. In this regard, this study attempts to look into the economic effects of expanding the manufacture and utilization of SRF facilities by applying an inter-industry analysis using a 2014 input-output table. Specifically, by applying the demand-driven model presents the results for the production-inducing effect, value-added creation effect, and employment-inducing effect. In particular, this study attempted to redefine for the SRF. In addition, it was accessed by exogenous around the manufacture and utilization of SRF sector. The results show that production-inducing effect and value-added creation effect of expanding the manufacture and utilization of SRF facilities for the investment of 1.0 won are estimated to be 1.9993 and 0.6747, respectively. The employment-inducing effect of one billion of investment in the expanding the manufacture and utilization of SRF facilities is computed to be 11.1982 persons. This information can be utilized in predicting the economic effects of the manufacture and utilization of SRF.