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Reducing Test Power and Improving Test Effectiveness for Logic BIST

  • Wang, Weizheng;Cai, Shuo;Xiang, Lingyun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.5
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    • pp.640-648
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    • 2014
  • Excessive power dissipation is one of the major issues in the testing of VLSI systems. Many techniques are proposed for scan test, but there are not so many for logic BIST because of its unmanageable randomness. This paper presents a novel low switching activity BIST scheme that reduces toggle frequency in the majority of scan chain inputs while allowing a small portion of scan chains to receive pseudorandom test data. Reducing toggle frequency in the scan chain inputs can reduce test power but may result in fault coverage loss. Allowing a small portion of scan chains to receive pseudorandom test data can make better uniform distribution of 0 and 1 and improve test effectiveness significantly. When compared with existing methods, experimental results on larger benchmark circuits of ISCAS'89 show that the proposed strategy can not only reduce significantly switching activity in circuits under test but also achieve high fault coverage.

The influence of vehicles on the flutter stability of a long-span suspension bridge

  • Han, Yan;Liu, Shuqian;Cai, C.S.;Zhang, Jianren;Chen, Suren;He, Xuhui
    • Wind and Structures
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    • v.20 no.2
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    • pp.275-292
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    • 2015
  • The presence of traffic on a slender long-span bridge deck will modify the cross-section profile of the bridge, which may influence the flutter derivatives and in turn, the critical flutter wind velocity of the bridge. Studies on the influence of vehicles on the flutter derivatives and the critical flutter wind velocity of bridges are rather rare as compared to the investigations on the coupled buffeting vibration of the wind-vehicle-bridge system. A typical streamlined cross-section for long-span bridges is adopted for both experimental and analytical studies. The scaled bridge section model with vehicle models distributed on the bridge deck considering different traffic flow scenarios has been tested in the wind tunnel. The flutter derivatives of the modified bridge cross section have been identified using forced vibration method and the results suggest that the influence of vehicles on the flutter derivatives of the typical streamlined cross-section cannot be ignored. Based on the identified flutter derivatives, the influence of vehicles on the flutter stability of the bridge is investigated. The results show that the effect of vehicles on the flutter wind velocity is obvious.

On Efficient Processing of Continuous Reverse Skyline Queries in Wireless Sensor Networks

  • Yin, Bo;Zhou, Siwang;Zhang, Shiwen;Gu, Ke;Yu, Fei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.4
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    • pp.1931-1953
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    • 2017
  • The reverse skyline query plays an important role in information searching applications. This paper deals with continuous reverse skyline queries in sensor networks, which retrieves reverse skylines as well as the set of nodes that reported them for continuous sampling epochs. Designing an energy-efficient approach to answer continuous reverse skyline queries is non-trivial because the reverse skyline query is not decomposable and a huge number of unqualified nodes need to report their sensor readings. In this paper, we develop a new algorithm that avoids transmission of updates from nodes that cannot influence the reverse skyline. We propose a data mapping scheme to estimate sensor readings and determine their dominance relationships without having to know the true values. We also theoretically analyze the properties for reverse skyline computation, and propose efficient pruning techniques while guaranteeing the correctness of the answer. An extensive experimental evaluation demonstrates the efficiency of our approach.

Immune Checkpoint Inhibitors: Therapeutic Tools for Breast Cancer

  • Su, Min;Huang, Chun-Xia;Dai, Ai-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.905-910
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    • 2016
  • Breast cancer is one of the major threats to female health, and its incidence is rapidly increasing in many countries. Currently, breast cancer is treated with surgery, followed by chemotherapy or radiation therapy, or both. However, a substantial proportion of breast cancer patients might have a risk for local relapse that leads to recurrence of their disease and/or metastatic breast cancer. Therefore searching for new and potential strategies for breast cancer treatment remains necessary. Immunotherapy is an attractive and promising approach that can exploit the ability of the immune system to identify and destroy tumors and thus prevent recurrence and metastatic lesions. The most promising and attractive approach of immunotherapeutic research in cancer is the blockade of immune checkpoints. In this review, we discuss the potential of certain inhibitors of immune checkpoints, such as antibodies targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed death 1 (PD-1) and lymphocyte activation gene-3 (LAG-3), in breast cancer therapeutics. Immune checkpoint inhibitors may represent future standards of care for breast cancer as monotherapy or combined with standard therapies.

Assessment of ride safety based on the wind-traffic-pavement-bridge coupled vibration

  • Yin, Xinfeng;Liu, Yang;Chen, S.R.
    • Wind and Structures
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    • v.24 no.3
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    • pp.287-306
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    • 2017
  • In the present study, a new assessment simulation of ride safety based on a new wind-traffic-pavement-bridge coupled vibration system is developed considering stochastic characteristics of traffic flow and bridge surface. Compared to existing simulation models, the new assessment simulation focuses on introducing the more realistic three-dimensional vehicle model, stochastic characteristics of traffic, vehicle accident criteria, and bridge surface conditions. A three-dimensional vehicle model with 24 degrees-of-freedoms (DOFs) is presented. A cellular automaton (CA) model and the surface roughness are introduced. The bridge deck pavement is modeled as a boundless Euler-Bernoulli beam supported on the Kelvin model. The wind-traffic-pavement-bridge coupled equations are established by combining the equations of both the vehicles in traffic, pavement, and bridge using the displacement and interaction force relationship at the patch contact. The numerical simulation shows that the proposed method can simulate rationally useful assessment and prevention information for traffic, and define appropriate safe driving speed limits for vulnerable vehicles under normal traffic and bridge surface conditions.

Dynamic analyses for an axially-loaded pile in a transverse-isotropic, fluid-filled, poro-visco-elastic soil underlain by rigid base

  • Zhang, Shiping;Zhang, Junhui;Zeng, Ling;Yu, Cheng;Zheng, Yun
    • Geomechanics and Engineering
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    • v.29 no.1
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    • pp.53-63
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    • 2022
  • Simplified analytical solutions are developed for the dynamic analyses of an axially loaded pile foundation embedded in a transverse-isotropic, fluid-filled, poro-visco-elastic soil with rigid substratum. The pile is modeled as a viscoelastic Rayleigh-Love rod, while the surrounding soil is regarded as a transversely isotropic, liquid-saturated, viscoelastic, porous medium of which the mechanical behavior is represented by the Boer's poroelastic media model and the fractional derivative model. Upon the separation of variables, the frequency-domain responses for the impedance function of the pile top, and the vertical displacement and the axial force along the pile shaft are gained. Then by virtue of the convolution theorem and the inverse Fourier transform, the time-domain velocity response of the pile head is derived. The presented solutions are validated, compared to the existing solution, the finite element model (FEM) results, and the field test data. Parametric analyses are made to show the effect of the soil anisotropy and the excitation frequency on the pile-soil dynamic responses.

Numerical investigation into particle crushing effects on the shear behavior of gravel

  • Xi Li;Yayan Liu;Guoping Qian;Xueqing Liu;Hao Wang;Guoqing Yin
    • Geomechanics and Engineering
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    • v.35 no.2
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    • pp.209-219
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    • 2023
  • This paper presents numerical investigations into the particle crushing effect on the shear properties of gravel under direct shear condition. A novel particle crushing model was developed based on the octahedral shear stress criterion and fragment replacement method. A series of direct shear tests were carried out on unbreakable particles and breakable particles with different strengths. The evolutions of the particle crushing, shear strength, volumetric strain behavior, and contact force fabric during shearing were analyzed. It was observed that the number of crushed particles increased with the increase of the shear displacement and axial pressure and decreased with the particle strength increasing. Moreover, the shear strength and volume dilatancy were obviously decreased with particle crushing. The shear displacement of particles starting to crush was close to that corresponding to the peak shear stress got. Besides, the shear-hardening behavior was obviously affected by the number of crushed particles. A microanalysis showed that due to particle crushing, the contact forces and anisotropy decreased. The mechanism of the particle crushing effect on the shear strength was further clarified in terms of the particle friction and interlock.

Aerodynamic mitigation of wind loads on a large-span cantilevered roof: A combined wind tunnel and CFD analysis

  • Chen Fubin;Wang Weijia;Yang Danqing;Zhenru Shu
    • Wind and Structures
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    • v.38 no.3
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    • pp.203-214
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    • 2024
  • Large-span cantilevered roof represents a unique type of structure that is vulnerable to wind loads. Inspired by the need to maximumly reducing the rooftop wind loads, this study examined the feasibility of positioning vented slots on the leading edge, and the effectiveness of such aerodynamic mitigation measures are assessed via both physical and numerical simulations. The reliability of numerical simulation was evaluated via comparisons with the wind tunnel tests. The results indicated that, the variation of venting hole arrangement can cause significant change in the rooftop wind load characteristics. For the cases involved in this study, the maximum reduction of mean and peak wind suction coefficients are found to be 9% and 8% as compared to the original circular slot without venting holes. In addition, the effect of slot shape is also evident. It was shown that the triangular shaped slot tends to increase the wind suction near the leading edge, whereas the hexagonal and octagonal shaped slots are found to decrease the wind suction. In particular, with the installation of octagonal shaped slot, the maximum reduction of wind suction coefficients near the leading edge reaches up to 31% as compared to the circular shaped slot, while the maximum reduction of mean wind suction coefficients is about 30%.

A STUDY ON NUTRITIONAL CHARACTERISTICS OF RICE STRAW IN CHINA

  • Tingxian, X.;Rejun, F.;Zhiliang, T.;Leihua, H.;Huiping, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.2
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    • pp.291-300
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    • 1993
  • The agronomic, morphologic and nutritive measurements were determined for ten varieties of the early-, medium- and late- maturing rice from five types of soil in south of China. The results are shown that (1) The higher contents of neutral detergent fibre (NDF), cellulose (CEL), hemicellulose (HC) and lignin (LIG), but lower crude protein (CP) and neutral detergent solubles (NDS) contents were noted for the whole plant of rice straw during maturation; (2) As far as the feed nutritive value, segments (S) is highest, then leaf blades (LB), leaf sheaths (LS) lowest. However, LB and LS are constituted about 75% of whole plant, the nutritive value of rice straw is depended upon the nutritive quality of LB and LS; (3) The dry matter disappearances (DMD) values of different spots of rice straw are different, the eary-maturing highest, then the medium; the late- lowest; (4) The DMD value of different fractions is different, S highest, then LB, LS lowest; (5) The different retention time in rumen, the DMD value of rice straw is different. As time following, the DMD value increased gradually, during 48-72 h, the DMD value achieves close to highest; (6) The grain yield (r = -0.91), plant height (r = -0.87) and full-filling grain percent (r = -0.75) are correlated negatively with DMD value, but the leaf/stem (r = 0.59) and the proportion of stem (r = 0.58) are correlated positively with DMD value. The relations between chemical compositions and DMD value are: Early-: DMD = 7.372 + 0.055 DM - 0.532 CP - 2.487 NDF + 1.143 ADF + 0.214 CEL + 1.456 HC + 0.718 LIG (r = 0.61). Medium-: DMD = 333.927 + 2.026 DM - 0.224 CP - 4.602 NDF + 4.524 ADF + 0.149 CEL + 2.923 HC + 0.035 LIG (r = 0.79). Late-: DMD = 133.284 + 0.282 DM - 3.455 CP - 22.185 NDF + 24.267 ADF + 0.316 CEL - 23.288 HC + 0.945 LIG (r = 0.79). Therefore, it is possible to predict the nutritive value of rice straw on the basis of the agronomic, morphologic measurements and chemical compositions and the relationship with DMD value.