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991.
We investigated the effect of a firm's resource capabilities and interaction processes on the success of IT outsourcing. Grounded in available literature on outsourcing relationship and process theory as well as a resource-based view of the IT resource capability, a conceptual model was composed to examine the causal structure of capability, process, and relationship in IT outsourcing. We identified the firm's resource capability factors and, based on the premise that relationship intensity should be affected by the IT outsourcing process, we developed a first-order factor analysis of resource capabilities in the interactions between the outsourcer and provider. Results of empirical testing using responses from 267 IT outsourcing project teams in Korea supported most of our hypotheses. The integration of corporate IT resource and capability theories with social exchange theory distinguishes our research from that of others, who have generally treated these theories separately.  相似文献   
992.
In this paper, a neural network model is presented to characterize the thickness and the uniformity of the cellgap process for flexible liquid crystal display (LCD). Input factors are explored via a D-optimal design with 15 runs and used as training data in the neural network. In order to verify the fitness of the model, three more runs are added as test data. Latin hypercube sampling and error back-propagation algorithm are used to build the model. Latin hypercube sampling is used to generate initial weights and biases of the network. The thickness of cellgap is measured at five points: one at the center and four at the edges. The average thickness is used as cellgap thickness, and the uniformity is obtained by comparing the thickness at the center and edge points.  相似文献   
993.
We study how to extend modal type systems based on intuitionistic modal logic S4 or S5 with a subtyping system based on intersection types. In the presence of four type constructors ${\!}\!\rightarrow \!{\!},\,{\!}\wedge {\!},\,\square {}$ , and $\Diamond {}$ , the traditional approach using a binary subtyping relation does not work well because of lack of orthogonality in subtyping rules and presence of a transitivity rule. We adopt the idea from the judgmental formulation of modal logic (Pfenning and Davies in Math Struct Comput Sci 11(4):511–540, 2001) and use subtyping judgments whose definitions express those notions internalized into type constructors directly at the level of judgments. The resultant judgmental subtyping systems admit cut rules similarly to a sequent calculus for intuitionistic logic and play a key role in designing and verifying the relational subtyping systems based on the binary subtyping relation. We use the proof assistant Coq to prove the admissibility of the cut rules and the equivalence between the two kinds of subtyping systems. The lesson from our study is that by using subtyping judgments instead of the binary subtyping relation, we can overcome the limitation usually associated with the syntactic approach to formulating subtyping systems.  相似文献   
994.
New robust and reliable H infinity control algorithms are suggested for discrete-time uncertain systems with time-varying norm-bounded parameter uncertainty in the state matrix as well as with actuator failure among a pre-specified subset of actuators. State feedback controllers can be obtained by deriving and solving modified parameter-dependent Riccati equations, which can stabilize the plant and guarantee a given H infinity-norm bound on attenuation of augmented disturbances - all admissible uncertainties as well as actuator failure. Two robust and reliable H infinity whether the process of fault accommodation is used or not. Performances of two controllers are evaluated through simulation studies for various failures. controllers are derived according to  相似文献   
995.
We present an efficient and robust algorithm for the landmark transfer on 3D meshes that are approximately isometric. Given one or more custom landmarks placed by the user on a source mesh, our method efficiently computes corresponding landmarks on a family of target meshes. The technique is useful when a user is interested in characterization and reuse of application-specific landmarks on meshes of similar shape (for example, meshes coming from the same class of objects). Consequently, across a set of multiple meshes consistency is assured among landmarks, regardless of landmark geometric distinctiveness. The main advantage of our method over existing approaches is its low computation time. Differently from existing non-rigid registration techniques, our method detects and uses a minimum number of geometric features that are necessary to accurately locate the user-defined landmarks and avoids performing unnecessary full registration. In addition, unlike previous techniques that assume strict consistency with respect to geodesic distances, we adopt histograms of geodesic distance to define feature point coordinates, in order to handle the deviation of isometric deformation. This allows us to accurately locate the landmarks with only a small number of feature points in proximity, from which we build what we call a minimal graph. We demonstrate and evaluate the quality of transfer by our algorithm on a number of Tosca data sets.  相似文献   
996.
Vertical handoff is one of the most important issues in the heterogeneous networks. While Lee et al. introduced a selective advance reservations and resource-aware handoff direction (SARAH) mechanism in order to provide a fast and efficient handoff with combination of layer 2 (L2) and layer 3 (L3) communications, there was a drawback that there was no consideration of handoff between heterogeneous network. In this paper, we improve the mechanism by providing security functions such as the neighbor-mapping server that binds IP address and MAC address with security support. At first, we discuss security issues in SARAH and proposed enhanced protocol. Finally, we show simple implementation results of our design in order to verify the practical aspects of our design.  相似文献   
997.
Volume ray-casting with a higher order reconstruction filter and/or a higher sampling rate has been adopted in direct volume rendering frameworks to provide a smooth reconstruction of the volume scalar and/or to reduce artifacts when the combined frequency of the volume and transfer function is high. While it enables high-quality volume rendering, it cannot support interactive rendering due to its high computational cost. In this paper, we propose a fast high-quality volume ray-casting algorithm which effectively increases the sampling rate. While a ray traverses the volume, intensity values are uniformly reconstructed using a high-order convolution filter. Additional samplings, referred to as virtual samplings, are carried out within a ray segment from a cubic spline curve interpolating those uniformly reconstructed intensities. These virtual samplings are performed by evaluating the polynomial function of the cubic spline curve via simple arithmetic operations. The min max blocks are refined accordingly for accurate empty space skipping in the proposed method. Experimental results demonstrate that the proposed algorithm, also exploiting fast cubic texture filtering supported by programmable GPUs, offers renderings as good as a conventional ray-casting algorithm using high-order reconstruction filtering at the same sampling rate, while delivering 2.5x to 3.3x rendering speed-up.  相似文献   
998.
This paper presents a multiple degree-of-freedom (DOF) energy bounding approach (EBA) for enhancing directional transparency while concurrently guaranteeing stability during multi-DOF haptic interactions. It was observed that the passivity condition for multiple ports may lead to oscillatory limit cycle behavior in some coordinate directions even though the total sum of energy flow-in is positive, meaning that the system is passive. The passivity condition, therefore, needs to be applied to each coordinate in order to avoid oscillatory behavior by ensuring that each energy flow-in is always positive. The EBA is applied to guarantee passivity. For multi-DOF haptic interaction, however, the EBA in each coordinate may distort the direction of the rendered force vector since the EBA may reduce the magnitude of the rendered force and torque vectors. To resolve this problem, a simple projection method is subsequently proposed. The validity of the proposed algorithm is then experimentally confirmed, and a comparative study with previous research is presented.  相似文献   
999.
Customized engineered fibers are currently being used extensively in the aerospace and automobile industries due to the ability to "design in" specific engineering characteristics. Understanding the thermal conductivity of these new fibers is critical for thermal management and design optimization. In the current investigation, a steady-state dc thermal bridge method (DCTBM) is developed to measure the thermal conductivity of individual poly(ether ketone) (PEK)/carbon nanotube (CNT) fibers. For non-conductive fibers, a thin platinum layer was deposited on the test articles to serve as the heater and temperature sensor. The effect of the platinum layer on the thermal conductivity is presented and discussed. DCTBM is first validated using gold and platinum wires (25 μm in diameter) over a temperature ranging from room temperature to 400 K with ±11% uncertainty, and then applied to PEK/CNT fibers with diverse CNT loadings. At a 28 wt. % CNT loading, the thermal conductivity of fibers at 390 K is over 27 Wm(-1)K(-1), which is comparable to some engineering alloys.  相似文献   
1000.
This paper presents a new climbing robotic mechanism for high-payload climbing and wall-to-wall transitioning. Payload capacity and transition ability are very important in climbing-robot applications for heavy industries and construction industries. The proposed robotic platform consists of three magnetic tread-wheel modules that are connected by links with two compliant joints. The front compliant joints are passive type with a torsion spring, and the rear compliant joints are active type with torque-controlled motors. A torque-controlled tail is attached at the end of the third module. Various transitions are achieved by the compliant joints, which change shape depending on the external conditions. High payloads are achieved by the large contact area of three magnetic tread-wheel modules. Detailed design issues are presented with analyses of the design parameters. The robot can perform two internal and two external transitions against gravity and every possible transition in the side surface driving direction. The robot can carry 10 kg payloads on vertical surfaces and on a ceiling. The ability to overcome a 30 mm diameter obstacle on vertical surfaces is also verified by experiments. The proposed robotic platform is going to be used in heavy industries.  相似文献   
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