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101.
Hsin-Hung Cho Chin-Feng Lai Timothy K. Shih Han-Chieh Chao 《Mobile Networks and Applications》2016,21(5):846-855
A mature cloud system needs a complete resource allocation policy which includes internal and external allocation. They not only enable users to have better experiences, but also allows the cloud provider to cut costs. In the other words, internal and external allocation are indispensable since a combination of them is only a total solution for whole cloud system. In this paper, we clearly explain the difference between internal allocation (IA) and external allocation (EA) as well as defining the explicit IA and EA problem for the follow up research. Although many researchers have proposed resource allocation methods, they are just based on subjective observations which lead to an imbalance of the overall cloud architecture, and cloud computing resources to operate se-quentially. In order to avoid an imbalanced situation, in previous work, we proposed Data Envelopment Analysis (DEA) to solve this problem; it considers all of a user’s demands to evaluate the overall cloud parameters. However, although DEA can provide a higher quality solution, it requires more time. So we use the Q-learning and Data Envelopment Analysis (DEA) to solve the imbalance problem and reduce computing time. As our simulation results show, the proposed DEA+Qlearning will provide almost best quality but too much calculating time. 相似文献
102.
103.
5.2 mW 61 dB SNDR 15 MHz Bandwidth CT ΔΣ Modulator Using Single Operational Amplifier and Single Feedback DAC 下载免费PDF全文
We propose an architecture that reduces the power consumption and active area of such a modulator through a reduction in the number of active components and a simplification of the topology. The proposed architecture reduces the power consumption and active area by reducing the number of active components and simplifying the modulator topology. A novel second‐order loop filter that uses a single operational amplifier resonator reduces the number of active elements and enhances the controllability of the transfer function. A trapezoidal‐shape half‐delayed return‐to‐zero feedback DAC eliminates the loop‐delay compensation circuitry and improves pulse‐delay sensitivity. These simple features of the modulator allow higher frequency operation and more design flexibility. Implemented in a 130 nm CMOS technology, the prototype modulator occupies an active area of 0.098 mm2 and consumes 5.23 mW power from a 1.2 V supply. It achieves a dynamic range of 62 dB and a peak SNDR of 60.95 dB over a 15 MHz signal bandwidth with a sampling frequency of 780 MHz. The figure‐of‐merit of the modulator is 191 fJ/conversion‐step. 相似文献
104.
Kyunghee Choi Young Tack Lee Jin Sung Kim Sung‐Wook Min Youngsuk Cho Atiye Pezeshki Do Kyung Hwang Seongil Im 《Advanced functional materials》2016,26(18):3146-3153
As one of the emerging new transition‐metal dichalcogenides materials, molybdenum ditelluride (α‐MoTe2) is attracting much attention due to its optical and electrical properties. This study fabricates all‐2D MoTe2‐based field effect transistors (FETs) on glass, using thin hexagonal boron nitride and thin graphene in consideration of good dielectric/channel interface and source/drain contacts, respectively. Distinguished from previous works, in this study, all 2D FETs with α‐MoTe2 nanoflakes are dual‐gated for driving higher current. Moreover, for the present 2D dual gate FET fabrications on glass, all thermal annealing and lithography processes are intentionally exempted for fully non‐lithographic method using only van der Waal's forces. The dual‐gate MoTe2 FET displays quite a high hole and electron mobility over ≈20 cm2 V?1 s?1 along with ON/OFF ratio of ≈105 in maximum as an ambipolar FET and also demonstrates high drain current of a few tens‐to‐hundred μA at a low operation voltage. It appears promising enough to drive organic light emitting diode pixels and NOR logic functions on glass. 相似文献
105.
The error-rate floor of low-density parity-check (LDPC) codes is attributed to the trapping sets of their Tanner graphs. Among them, fully absorbing sets dominantly affect the error-rate performance, especially for short blocklengths. Efficient methods to identify the dominant trapping sets of LDPC codes were thoroughly researched as exhaustively searching them is NP-hard. However, the existing methods are ineffective for Raptor-like LDPC codes, which have many types of trapping sets. An effective method to identify dominant fully absorbing sets of Raptor-like LDPC codes is proposed. The search space of the proposed algorithm is optimized into the Tanner subgraphs of the codes to afford time-efficiency and search-effectiveness. For 5G New Radio (NR) base graph (BG) 2 LDPC codes for short blocklengths, the proposed algorithm finds more dominant fully absorbing sets within one seventh of the computation time of the existing search algorithm, and its search-effectiveness is verified using importance sampling. The proposed method is also applied to 5G NR BG1 LDPC code and Advanced Television Systems Committee 3.0 type A LDPC code for large blocklengths. 相似文献
106.
Jiwoo Min Jaemin Im Seung Hyun Kim Hyun Ho Choi Kilwon Cho 《Advanced functional materials》2023,33(19):2212825
Molecular doping in conjugated polymers (CPs) has recently received intensive attention for its potential to achieve high electrical conductivity in organic thermoelectric materials. In particular, it affects not only the carrier density n but also the carrier mobility µ because high degree of molecular doping changes the morphological properties. Herein, the effect of molecular doping in CP thin films on the pathways and mechanisms of charge transport is investigated, which govern the µ-n relationship. Two representative donor–acceptor type CPs with similar µ but different molecular assembly in an undoped state, that is poly[2,5-(2-octyldodecyl)-3,6-diketopyrrolopyrrole-alt-5,5-(2,5-di(thien-2-yl)thieno[3,2-b]thiophene)] (DPPDTT) and indacenodithiophene-co-benzothiadiazole (IDTBT), are prepared. Heavy doping with iron chloride (FeCl3) induced DPPDTT with highly crystalline edge-on orientation to increase its µ up to 19.6 cm2 V−1 s−1, whereas IDTBT with irregular intermolecular stacking showed little change in µ. It is revealed that this different µ-n relationship is highly attributed to the initial molecular ordering of CP films. The charge transport mechanism also becomes significantly different: both coherent and incoherent transports are observed in the doped DPPDTT, whereas incoherent transport is only found in the doped IDTBT. This study suggests guidelines for enhancing charge transport of CPs under doping in terms of structural disorder. 相似文献
107.
Face Threat and Facework Strategies When Family (Health) Secrets Are Revealed: A Comparison of South Korea and the United States 下载免费PDF全文
This study examined face threat and facework strategies when people witness family members disclosing sensitive health information to family outsiders. Korean and U.S. participants were expected to view these situations differently based on Confucian versus individualist identity and in‐group privacy norms. Korean and U.S. college samples evaluated vignettes in which health information was disclosed to family outsiders. Koreans regarded the situations as more face threatening and endorsed dominating facework in these situations to a greater extent than did Americans. The 2 cultures also showed strong similarities. Results confirmed the cultural basis of privacy expectations but contradicted some accounts of culturally based facework. Koreans did not consistently endorse indirect facework, nor did Americans show notable directness in response to privacy violations. 相似文献
108.
109.
In this paper, we present an intellectual property management and protection (IPMP) system in a broadcasting environment to provide mechanisms for copyright and contents protection that are compliant with the MPEG‐2 and MPEG‐4 IPMP Extension (IPMPX) specifications. The technology for processing IPMP related information was exploited, and a terminal model has been successfully designed and implemented. In addition, interoperability, which is the main objective of MPEG‐2/4 IPMPX, has been addressed in detail. The experimental results show that the implemented system performs the IPMP process well, meeting the requirements of a broadcasting environment. 相似文献
110.
Heon-Bok Lee Hyun Jeong Yang Ju Hyung We Kukjoo Kim Kyung Cheol Choi Byung Jin Cho 《Journal of Electronic Materials》2011,40(5):615-619
A new process for fabricating a low-cost thermoelectric module using a screen-printing method has been developed. Thermoelectric
properties of screen-printed ZnSb films were investigated in an effort to develop a thermoelectric module with low cost per
watt. The screen-printed Zn
x
Sb1−x
films showed a low carrier concentration and high Seebeck coefficient when x was in the range of 0.5 to 0.57 and the annealing temperature was kept below 550°C. When the annealing temperature was higher
than 550°C, the carrier concentration of the Zn
x
Sb1−x
films reached that of a metal, leading to a decrease of the Seebeck coefficient. In the present experiment, the optimized
carrier concentration of screen-printed ZnSb was 7 × 1018/cm3. The output voltage and power density of the ZnSb film were 10 mV and 0.17 mW/cm2, respectively, at ΔT = 50 K. A thermoelectric module was produced using the proposed screen-printing approach with ZnSb and CoSb3 as p-type and n-type thermoelectric materials, respectively, and copper as the pad metal. 相似文献