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971.
We study quantum teleportation between two different types of optical qubits using hybrid entanglement as a quantum channel under decoherence effects. One type of qubit employs the vacuum and single-photon states for the basis, called a single-rail single-photon qubit, and the other utilizes coherent states of opposite phases. We find that teleportation from a single-rail single-photon qubit to a coherent-state qubit is better than the opposite direction in terms of fidelity and success probability. We compare our results with those using a different type of hybrid entanglement between a polarized single-photon qubit and a coherent state. 相似文献
972.
Ji-Hoon Choi Yong-Woon Park Jae-Bok Song In-So Kweon 《International Journal of Control, Automation and Systems》2011,9(4):716-725
GPS/INS integrated systems do not guarantee robustness and accuracy of localization, because GPS has vulnerability to external
disturbances. However, the overall performance and reliability of the system can be significantly improved by fusing multiple
sensors with a different operating principle. In outdoor environments where GPS may be blocked, there are many features compared
to the open space and these features can provide much information for UGV localization. Thus, this paper proposes an improved
localization algorithm based on the hierarchical federation of three measurement layers, i.e., GPS, INS, and visual localization,
to overcome the shortcomings of GPS/INS integrated systems. The proposed algorithm automatically switches the operation modes
according to GPS status and a network of a ground-based reference station. A vocabulary tree with SURF is used in the visual
localization method. In the data fusion of visual localization and INS, an asynchronous and time-delayed data fusion algorithm
is presented because visual localization is always time-delayed compared with INS. By using DGPS to obtain the reference position
under the dynamic conditions of the reference station, the restrictions of the conventional DGPS are overcome and all UGVs
within WiBro communication range of the reference station can accurately estimate the position with a common GPS. The experiment
results with a predefined path demonstrate enhancement of the robustness and accuracy of localization in outdoor environments. 相似文献
973.
A signature-based intrusion detection system identifies intrusions by comparing the data traffic with known signature patterns. In this process, matching of packet strings against signature patterns is the most time-consuming step and dominates the overall system performance. Many signature-based network intrusion detection systems (NIDS), e.g., the Snort, employ one or multiple pattern matching algorithms to detect multiple attack types. So far, many pattern matching algorithms have been proposed. Most of them use single-byte standard unit for search, while a few algorithms such as the Modified Wu-Manber (MWM) algorithm use typically two-byte unit, which guarantees better performance than others even as the number of different signatures increases. Among those algorithms, the MWM algorithm has been known as the fastest pattern matching algorithm when the patterns in a rule set rarely appear in packets. However, the matching time of the MWM algorithm increases as the length of the shortest pattern in a signature group decreases.In this paper, by extending the length of the shortest pattern, we minimize the pattern matching time of the algorithm which uses multi-byte unit. We propose a new pattern matching algorithm called the L+1-MWM algorithm for multi-pattern matching. The proposed algorithm minimizes the performance degradation that is originated from the dependency on the length of the shortest pattern. We show that the L+1-MWM algorithm improves the performance of the MWM algorithm by as much as 20% in average under various lengths of shortest patterns and normal traffic conditions. Moreover, when the length of the shortest pattern in a rule set is less than 5, the L+1-MWM algorithm shows 38.87% enhancement in average. We also conduct experiments on a real campus network and show that 12.48% enhancement is obtained in average. In addition, it is shown that the L+1-MWM algorithm provides a better performance than the MWM algorithm by as much as 25% in average under various numbers of signatures and normal traffic conditions, and 20.12% enhancement in average with real on-line traffic. 相似文献
974.
Target sales rebate (TSR) contracts have been shown to be useful in coordinating supply chains with risk-neutral agents. However, there have been few studies on the cases with risk sensitive agents. As a result, based on the classic Markowitz portfolio theory in finance, we carry out in this paper a mean–variance (MV) analysis of supply chains under TSR contracts. We study a supply chain with a single supplier and a single risk averse retailer. We propose TSR contracts for achieving coordination. We demonstrate how TSR contracts can coordinate the supply chain which takes into consideration the degree of risk aversion of the retailer. We find that the supplier can coordinate the channel with flexible TSR contracts. In addition, we extend the supply chain model to include sales effort decision of the retailer. Conditions for TSR contracts to coordinate the supply chain with sales effort of retailer are also derived. 相似文献
975.
Hongseok Choi Datta A. Xudong Cheng Xiaochun Li 《Journal of microelectromechanical systems》2006,15(2):322-329
Effective monitoring and diagnosis of manufacturing processes is of critical importance. If critical manufacturing process conditions are continuously monitored, problems can be detected and solved during the processing cycle. However, current technology still evidently lags behind practical needs. Microfabricated thin-film thermocouples and strain gauges are attractive for their small size and fast response. It is challenging to fabricate and embed these sensors into metallic components that are widely used in manufacturing. This paper investigates the fabrication, embedding, and characterization of metal embedded thin-film thermocouples and strain gauges. The materials (dielectric and metallic) constituting a complete microsensor were characterized and optimized. The results obtained from characterization and optimization of materials are presented and discussed. Thin-film thermocouples on stainless steel substrates (before and after embedding) were calibrated to elevated temperatures. The behavior of thin-film strain gauges was also studied. The metal embedded sensors demonstrated good accuracy, sensitivity, and linearity that matched the performance of commercial thermocouples and strain gauges well. The metal embedded microsensors are promising for in situ monitoring in hostile manufacturing environments. 相似文献
976.
Hyung Rim Reference to Choi Hyun Soo Reference to Kim Young Jae Reference to Park Kyoung Hwan Reference to Kim Myung Ho Reference to Joo Hyung Soo Reference to Sohn 《Decision Support Systems》2000,28(4):333
The sales activity of most parts manufacturing companies is based on orders of buyers. The process of promotion, receipt and selection of orders of the parts manufacturers is closely coupled with the load status of the production lines. On deciding whether to accept an order or not, as well as negotiating with buyers, sales persons need information such as load and schedule of production lines, and manufacturability of the order. Manufacturability analysis, process planning, and scheduling are therefore key features in developing an agent of sales activity for the parts manufacturing business. In this paper, an intelligent agent, a virtual manufacturing-based sales agent (VMSA) with multi-agent architecture is proposed to support the sales activity for the parts manufacturers in the Internet environment. A VMSA has an integrated architecture of agent and virtual manufacturing. The prototype of VMSA has been developed for a machine parts manufacturing company that has lathe machines, drilling machines, cutting machines, and milling machines. 相似文献
977.
Seog‐Young Lee Mi‐Yeon Lee Won‐Yeol Choi Dong‐Heon Lee Yong‐Seog Kim 《Journal of the Society for Information Display》2008,16(12):1219-1227
Abstract— In an attempt to reduce materials and processing costs of ACPDPs, aluminum fence electrodes were prepared on soda‐lime glass substrates by chemically etching aluminum foil bonded directly onto the substrate via an anodic‐bonding process. Several different fence‐electrode patterns were designed and coated either with a glass dielectric layer or with an anodic aluminum oxide layer. Firing voltages, operation margin, luminance, and luminous efficiency of such test panels were evaluated. The results indicated that the performance of test panels with aluminum fence electrodes is comparable with conventional test panels with ITO/Ag electrodes, demonstrating the possibility of a dramatic reduction in the costs of ACPDPs. 相似文献
978.
In this paper, the fuzzy group method data handling-type (GMDH) neural networks and their application to the forecasting of mobile communication systems are described. At present, the GMDH family of modeling algorithms discovers the structure of empirical models and it gives only the way to get the most accurate identification and demand forecasts in case of noised and short input sampling. In distinction to neural networks, the results are explicit mathematical models, obtained in a relative short time. In this paper, an adaptive learning network is proposed as a kind of neural-fuzzy GMDH. The proposed method can be reinterpreted as a multi-stage fuzzy decision rule which is called the neural-fuzzy GMDH. The GMDH-type neural networks have several advantages compared with conventional multi-layered GMDH models. Therefore, many types of nonlinear systems can be automatically modeled by using the neuro-fuzzy GMDH. A computer program is developed and successful applications are shown in the field of estimating problems of mobile communication with a number of factors considered. 相似文献
979.
A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have
been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal
model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal
schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s
temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query
performance on feature history by removing topological comparison during query process. Further, a prototype system has been
developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of
temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.
相似文献
E. Lynn UseryEmail: |
980.
Nguyen Hai Duong Na In Seop Kim Soo Hyung Lee Guee Sang Yang Hyung Jeong Choi Jun Ho 《Multimedia Tools and Applications》2019,78(4):4563-4577
Multimedia Tools and Applications - Object tracking, especially human tracking is one of the challenging research problems in computer vision. Although the performance has gained some positive... 相似文献