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排序方式: 共有6873条查询结果,搜索用时 15 毫秒
71.
Tran Quang Hung Sunjong Oh Jong-Ryul Jeong CheolGi Kim 《Sensors and actuators. A, Physical》2010,157(1):42-46
The planar Hall effect (PHE) sensor with a junction size of 3 μm × 3 μm for a single micro-bead detection has been fabricated successfully using a typical spin-valve thin film Ta(5)/NiFe(16)/Cu(1.2)/NiFe(2)/IrMn(15)/Ta(5) nm. The PHE sensor exhibits a sensitivity of about 7.2 μV Oe?1 in the magnetic field range of ±7 Oe approximately. We have performed an experiment to illustrated the possibility of single micro-bead detection by using a PHE sensor. A single micro-bead of 2.8 μm diameter size is secluded from 0.1% dilute solution of the Dynabeads® M-280 dropped on the sensor surface and is located on the sensor junction by using a micro magnetic needle. The comparison of the PHE voltage profiles in the field range from 0 to 20 Oe in the absence and presence of a single micro-bead identifies a single Dynabeads® M-280, the maximal signal change as large as ΔV ~ 1.1 μV can be obtained at the field ~6.6 Oe. The results are well described in terms of the reversal of a basic single domain structure. 相似文献
72.
Song Hak Kim Chun Keun Jang Sung Hoon Jeong Jae Yun Jaung 《Journal of the Society for Information Display》2010,18(11):994-1009
Abstract— Even though dyes have a fine resolution and good chromaticities, they are not widely used as coloring materials for color filters (CFs) due to their low thermal stability and chemical resistance. A series of azo‐dye derivatives, which consist of two cross‐linkable acrylate or methacrylate groups to improve thermal and chemical properties, have been synthesized and used to fabricate color filters. The spectral properties and chemical/thermal stabilities of the fabricated CFs were investigated by comparing dye‐based CFs, without a complicated dispersion process, but with pigment‐based CFs using dispersed pigment. Also, more properties including the development test and surface morphologies lithographic properties were studied. The synthesized azo dyes were characterized by elemental analysis, UV‐visible spectra, IR, mass, and 1H‐NMR spectra. 相似文献
73.
Gu-Min Jeong Hyun-Sik Ahn Sang-Il Choi Nojun Kwak Chanwoo Moon 《International Journal of Control, Automation and Systems》2010,8(1):141-148
In this paper, we propose a new pattern recognition method using feature feedback and present its application to face recognition.
Conventional pattern recognition methods extract the features employed for classification using PCA, LDA and so on. On the
other hand, in the proposed method, the extracted features are analyzed in the original space using feature feedback. Using
reverse mapping from the extracted features to the original space, we can identify the important part of the original data
that affects the classification. In this way, we can modify the data to obtain a higher classification rate, make it more
compact or abbreviate the required sensors. To verify the applicability of the proposed method, we apply it to face recognition
using the Yale Face Database. Each face image is divided into two parts, the important part and unimportant part, using feature
feedback, and the classification performed using the feature mask obtained from feature feedback. Also, we combine face recognition
with image compression. The experimental results show that the proposed method works well. 相似文献
74.
Bi-objective scheduling for reentrant hybrid flow shop using Pareto genetic algorithm 总被引:1,自引:0,他引:1
Hang-Min Cho Suk-Joo Bae Jungwuk Kim In-Jae Jeong 《Computers & Industrial Engineering》2011,61(3):529-541
This paper deals with a scheduling problem for reentrant hybrid flowshop with serial stages where each stage consists of identical parallel machines. In a reentrant flowshop, a job may revisit any stage several times. Local-search based Pareto genetic algorithms with Minkowski distance-based crossover operator is proposed to approximate the Pareto optimal solutions for the minimization of makespan and total tardiness in a reentrant hybrid flowshop. The Pareto genetic algorithms are compared with existing multi-objective genetic algorithm, NSGA-II in terms of the convergence to optimal solution, the diversity of solution and the dominance of solution. Experimental results show that the proposed crossover operator and local search are effective and the proposed algorithm outperforms NSGA-II by statistical analysis. 相似文献
75.
Juyoung Wy Sangwon Jeong Byung-In Kim Junhyuk Park Jaejoon Shin Hyunjoong Yoon Sujeong Lee 《Computers & Industrial Engineering》2011
Simulation has been used to evaluate various aspects of manufacturing systems. However, building a simulation model of a manufacturing system is time-consuming and error-prone because of the complexity of the systems. This paper introduces a generic simulation modeling framework to reduce the simulation model build time. The framework consists of layout modeling software and a data-driven generic simulation model. The generic simulation model was developed considering the processing as well as the logistics aspects of assembly manufacturing systems. The framework can be used to quickly develop an integrated simulation model of the production schedule, operation processes and logistics of a system. The framework was validated by developing simulation models of cellular and conveyor manufacturing systems. 相似文献
76.
With the development in IT technology and with growing demands of users, a ubiquitous environment is being made. Because individual
identification is important in ubiquitous environment, RFID technology would be used frequently. RFID is a radio frequency
identification technology to replace bar code. The reader transmits query (request of user information) and tag-provides user
information. RFID has various advantages, such as high speed identification rates, mass memory storages. However, eavesdropping
is possible as well as a problem that user information is exposed (Juels et al. in Conference on Computer and Communications
Security—ACM CCS, pp. 103–111, 2003; Ohkubo et al. in RFID Privacy Workshop 2003; Weis et al. in International Conference on Security in Pervasive Computing, pp. 201–212, 2003; Weis et al. in Cryptographic Hardware and Embedded Systems—CHES, pp. 454–469, 2002). Therefore, when off-line customer had visited bank for banking service, RNTS (RFID number ticket service) system provides
both anonymity in customer identification and efficiency of banking service. In addition, RNTS system protects privacy of
an off-line user visiting the bank and it is an efficient method offering service in order of arriving in the bank. 相似文献
77.
Ab initio predictions of secondary structures in proteins have to combine local predictions, based on short fragments of the
protein sequence, with consistency restrictions, as not all locally plausible predictions may be simultaneously true.
We use the fact that secondary structures are patterns of hydrogen bonds and that a single residue can participate in hydrogen
bonds of at most one secondary structure. Consistency of fixed-sized pieces of secondary structures is the easiest to approximate
and we formalize it as 1-2 matching problem. Consistency of entire secondary structures is a version of set packing. We also
investigate how to form a simple problem if we add the requirement that the secondary structure and the loops that connect
them fit together in a metric space.
Every problem that we investigated is MAX-SNP hard and it has a constant factor approximation. Computational experience suggests
that in biological instances, we can find nearly optimal solutions using heuristics. 相似文献
78.
String inclusion and non-inclusion problems have been vigorously studied in such diverse fields as molecular biology, data compression, and computer security. Among the well-known string inclusion or non-inclusion notions, we are interested in the longest common nonsuperstring. Given a set of strings, the longest common nonsuperstring problem is finding the longest string that is not a superstring of any string in the given set. It is known that the longest common nonsuperstring problem is solvable in polynomial time.In this paper, we propose an efficient algorithm for the longest common nonsuperstring problem. The running time of our algorithm is linear with respect to the sum of the lengths of the strings in the given set, using generalized suffix trees. 相似文献
79.
This paper focuses on recently advanced fuzzy models and the application of type-2 fuzzy sets in video deinterlacing. The final goal of the proposed deinterlacing algorithm is to exactly determine an unknown pixel value while preserving the edges and details of the image. To begin, we will discuss some artefacts of spatial, temporal, and spatio-temporal domain deinterlacing methods. In order to address the aforementioned issues, we adopted type-2 fuzzy sets concepts to design a weight evaluating approach. In the proposed method, the upper and lower fuzzy membership functions of the type-2 fuzzy logic filters are derived from the type-1 (or primary) fuzzy membership function. The weights from upper and lower membership functions are considered to be multiplied with the candidate deinterlaced pixels. Experimental results proved that the performance of the proposed method was superior, both objectively and subjectively to other different conventional deinterlacing methods. Moreover, the proposed method preserved the smoothness of the original image edges and produced a high-quality progressive image. 相似文献
80.
The FP-growth algorithm using the FP-tree has been widely studied for frequent pattern mining because it can dramatically improve performance compared to the candidate generation-and-test paradigm of Apriori. However, it still requires two database scans, which are not consistent with efficient data stream processing. In this paper, we present a novel tree structure, called CP-tree (compact pattern tree), that captures database information with one scan (insertion phase) and provides the same mining performance as the FP-growth method (restructuring phase). The CP-tree introduces the concept of dynamic tree restructuring to produce a highly compact frequency-descending tree structure at runtime. An efficient tree restructuring method, called the branch sorting method, that restructures a prefix-tree branch-by-branch, is also proposed in this paper. Moreover, the CP-tree provides full functionality for interactive and incremental mining. Extensive experimental results show that the CP-tree is efficient for frequent pattern mining, interactive, and incremental mining with a single database scan. 相似文献