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191.
Edible films can be used as wrapping material on food products to reduce surface contamination. The incorporation of antimicrobials into edible films could serve as an additional barrier against pathogenic and spoilage microorganisms that contaminate food surfaces. The objective of this study was to investigate the antimicrobial effects of carvacrol and cinnamaldehyde, incorporated into apple, carrot, and hibiscus-based edible films against Listeria monocytogenes on contaminated ham and bologna. Ham or bologna samples were inoculated with L. monocytogenes and dried for 30 min, then surface wrapped with edible films containing the antimicrobials at various concentrations. The inoculated, film-wrapped samples were stored at 4 °C. Samples were taken at day 0, 3, and 7 for enumeration of surviving L. monocytogenes by plating on appropriate media. Carvacrol films showed better antimicrobial activity than cinnamaldehyde films. Compared to control films without antimicrobials, films with 3% carvacrol induced 1 to 3, 2 to 3, and 2 to 3 log CFU/g reductions on ham and bologna at day 0, 3, and 7, respectively. Corresponding reductions with 1.5% carvacrol were 0.5 to 1, 1 to 1.5, and 1 to 2 logs, respectively. At day 7, films with 3% cinnamaldehyde reduced L. monocytogenes population by 0.5 to 1.5 and 0.5 to 1.0 logs on ham and bologna, respectively. Inactivation by apple films was greater than that by carrot or hibiscus films. Apple films containing 3% carvacrol reduced L. monocytogenes population on ham by 3 logs CFU/g on day 0 which was 1 to 2 logs greater than that by carrot and hibiscus films. Films were more effective on ham than on bologna. The food industry and consumers could use these films to control surface contamination by pathogenic microorganisms. PRACTICAL APPLICATION: Antimicrobial edible, food-compatible film wraps prepared from apples, carrots, and hibiscus calyces can be used by the food industry to inactivate Listeria monocytogenes on widely consumed ready to eat meat products such as bologna and ham. This study provides a scientific basis for large-scale application of edible fruit- and vegetable-based antimicrobial films on foods to improve microbial food safety.  相似文献   
192.
See‐through displays (STD) like head‐up displays (HUD) play major role in providing aircraft data to pilot through a visual interface. The data is displayed in form of symbology in pilot's line of sight using vector scanning technique and is deciphered to get flight and mission information. Contrast ratio required to see against bright sunlight at high altitudes is given only by luminance of cathode ray tube (CRT). Therefore, CRT is still used as display source in avionic HUDs, although other devices are also being explored for these applications. Aircraft's night mode operation requires raster display of external scene information along with vector data display due to low visibility during night. It reduces time available for writing vector data during night mode resulting in reduced symbology. Conventionally used raster scanning methods are unidirectional scanning methods. Bidirectional raster scanning (BRS) is an unconventional approach which scans display screen from both directions. In present work, an algorithm for BRS has been developed in VHDL providing more time for vector writing by increasing vertical retrace period (VRP) of raster scanning. Functional verification of design has been performed by simulations carried out through test‐bench and VRP is increased to 5.8304 ms from conventional 1.2800 ms per field.  相似文献   
193.

In this era of Internet, the exchange of data between the users and service providers has grown tremendously. Organizations in health, banking, social network, criminal and government sectors have been collecting and processing the individuals’ information for their gainful purpose. However, collecting and sharing of the individuals’ information which could be sensitive and confidential, for data mining may cause a breach in data privacy. In many applications, selective data collection of confidential and sensitive information of the users’ needs to be modified for preserving it from unauthorized access and disclosure. Many data mining techniques that include statistical, k-anonymity, cryptographic, perturbation and randomization methods, etc. have been evolved for protecting and preserving data privacy. These techniques have their own limitations, it may be the case that the privacy protection is adequate or computations complexities are high and expensive. To address the limitations of the above-mentioned techniques, a methodology comprising of encoding and randomization, is proposed to preserve privacy. This technique called as Randomized Encoding (RE) technique, in which encoding is performed with addition of random noise from a known distribution to the original data for perturbing the data before its release to the public domain. The core component of this technique is a novel primitive of using Randomized Encoding (RE) which is quite similar to the spirit of other cryptographic algorithms. The reconstruction of an approximation to the original data distribution is done from the perturbed data and used for data mining purposes. There is always a trade-off between information loss and privacy preservation. To achieve balance between privacy and data utility, the dataset attributes are first classified into sensitive and quasi-identifiers. The pre-classified confidential and sensitive data attributes are perturbed using Base 64 encoding with addition of a randomly generated noise for preserving privacy. In this variable dynamic proposed approach, the result analysis of the experiment conducted suggests that the proposed technique performs computationally efficient and preserves privacy while adequately maintaining data utility in comparison with other privacy preserving techniques such as anonymization approach.

  相似文献   
194.
In this article, a novel resonant series slot linearly polarized antenna is realized using substrate integrated waveguide (SIW) technology for industrial scientific medical radio band (ISM) at 5.8 GHz. The proposed antenna consists of two 24° inclined slots and two metallic vias to produce alternate inductive and capacitive loads. The rectangular slots are introduced at the top metallic surface at an angle of 24° from the Y‐axis to excite a hybrid mode (TE110 + TE120) near to the modified cavity mode TE120. The resonant slots are excited with the help of an inset microstrip feedline which retain its planar integrability. The slots are excited to resonate in the TE120 mode at 5.8 GHz. To enhance the bandwidth, the location of two shorting vias are optimized in proximity to the slots. These vias help to couple the hybrid mode and the cavity modes in the desired frequency band, which leads to enhancement in the bandwidth significantly. The proposed geometry is fabricated and experimentally verified. The measured and simulated results depict a good co‐relation which show measured ?10 dB fractional bandwidth of 5.2% with a maximum gain of 7.15 dBi and the front to back ratio better than 15 dB at 5.8 GHz.  相似文献   
195.
The room temperature response characteristics of SnO2 thin film sensor loaded with platinum catalyst clusters are investigated for LPG under the exposure of ultraviolet radiation. The SnO2-Pt cluster sensor structures have been prepared using rf sputtering. Combined effect of UV radiation exposure (λ = 365 nm) and presence of Pt catalyst clusters (10 nm thick) on SnO2 thin film sensor surface is seen to lead to an enhanced response (4.4 × 103) for the detection of LPG (200 ppm) at room temperature whereas in the absence of UV illumination a comparable response (∼5 × 103) could be obtained but only at an elevated temperature of 220 °C. The present study therefore investigates the effect of UV illumination on LPG sensing characteristics of SnO2 sensors loaded with Pt clusters of varying thickness values. Results indicate the possibility of utilizing the sensor structure with novel dispersal of Pt catalyst clusters on SnO2 film surface for efficient detection of LPG at room temperature under the illumination of UV radiations.  相似文献   
196.
197.
Nanocomposites of high-density polyethylene along with ultrafine fly ash and acid-functionalized multiwalled carbon nanotubes have been developed. To enhance the interfacial adhesion, an epoxy-functionalized high-density polyethylene has been added, while the ultrafine fly ash has been surface modified using aminosilane-coupling agent. Improvement in mechanical properties using both ultrafine fly ash/multiwalled carbon nanotubes was seen and was further analyzed using micromechanical models. The addition of ultrafine fly ash and multiwalled carbon nanotubes together exhibited synergism leading to lowering of peak heat release rate. The nanocomposites showed enhanced thermal stability and lowered crystallinity percentage values of the high-density polyethylene phase due to improved interfacial interactions.  相似文献   
198.
Imidazolinium surfactants belong to the category of cationic surfactants that have already gained the great interest of researchers due to their varied range of commercial applications. With the advancement in the field of surfactants research, imidazolinium surfactants are being converted into their corresponding gemini surfactants. Gemini surfactants are known to have exceptional self‐assembling characteristics and exclusive interfacial activity that include much lower CMC and better ability to reduce surface tension than their conventional monomeric counterparts. Long reaction time associated with conventional thermal synthetic procedures and high production costs are the two major issues involved in the synthesis of gemini surfactants. The present research work involves the microwave synthesis of novel gemini imidazolinium surfactants with carbonate linkage. In order to synthesize cost effective gemini surfactants, waste cooking oils have been used as raw materials. Structural characterization of synthesized gemini surfactants has been achieved through 1H‐NMR, 13C‐NMR and FT‐IR.  相似文献   
199.
Abstract

Terrorist groups have reconnoitered smarter ways to use online discussion forums for their violent plans. They have been using their privately owned discussion forums for various illegal purposes. A comparative study of work done on various dark web forums of terroristic organizations is done in this paper. This paper proposes a novel approach to identify procurement of modern weapons over the social media forum by terrorist groups. We used data from four dark web forum websites named “Ansar Aljihad Network”, “IslamicAwakening”, “Gawaher”, and “IslamicNetwork”. Multiple experts independently annotated 313 randomly selected posts as procurement (YES) or non- procurement (NO) to label the forum threads. Mutual agreement between experts is computed to find the level of significance. Furthermore, we used machine learning classification techniques (MLCT) in order to classify labeled posts. To our knowledge, our procurement model presents a first of its kind model to automatically detect procurement of modern weapons over dark web. The work done presents application of social media analytics and text mining to counter terrorism.  相似文献   
200.
Theory of relative defect proneness   总被引:1,自引:1,他引:0  
In this study, we investigated the functional form of the size-defect relationship for software modules through replicated studies conducted on ten open-source products. We consistently observed a power-law relationship where defect proneness increases at a slower rate compared to size. Therefore, smaller modules are proportionally more defect prone. We externally validated the application of our results for two commercial systems. Given limited and fixed resources for code inspections, there would be an impressive improvement in the cost-effectiveness, as much as 341% in one of the systems, if a smallest-first strategy were preferred over a largest-first one. The consistent results obtained in this study led us to state a theory of relative defect proneness (RDP): In large-scale software systems, smaller modules will be proportionally more defect-prone compared to larger ones. We suggest that practitioners consider our results and give higher priority to smaller modules in their focused quality assurance efforts.
Divya MathewEmail:

A. Güneş Koru   received a B.S. degree in Computer Engineering from Ege University, İzmir, Turkey in 1996, an M.S. degree in Computer Engineering from Dokuz Eylül University, İzmir, Turkey in 1998, an M.S. degree in Software Engineering from Southern Methodist University (SMU), Dallas, TX in 2002, and a Ph.D. degree in Computer Science from SMU in 2004. He is an assistant professor in the Department of Information Systems at University of Maryland, Baltimore County (UMBC). His research interests include software quality, measurement, maintenance, and evolution, open source software, bioinformatics, and healthcare informatics. Khaled El Emam   is an Associate Professor at the University of Ottawa, Faculty of Medicine and the School of Information Technology and Engineering. He is a Canada Research Chair in Electronic Health Information at the University of Ottawa. Previously Khaled was a Senior Research Officer at the National Research Council of Canada, and prior to that he was head of the Quantitative Methods Group at the Fraunhofer Institute in Kaiserslautern, Germany. In 2003 and 2004, he was ranked as the top systems and software engineering scholar worldwide by the Journal of Systems and Software based on his research on measurement and quality evaluation and improvement, and ranked second in 2002 and 2005. He holds a Ph.D. from the Department of Electrical and Electronics, King’s College, at the University of London (UK). His labs web site is: . Dongsong Zhang   is an Associate Professor in the Department of Information Systems at University of Maryland, Baltimore County. He received his Ph.D. in Management Information Systems from the University of Arizona. His current research interests include context-aware mobile computing, computer-mediated collaboration and communication, knowledge management, and open source software. Dr. Zhang’s work has been published or will appear in journals such as Communications of the ACM (CACM), Journal of Management Information Systems (JMIS), IEEE Transactions on Knowledge and Data Engineering (TKDE), IEEE Transactions on Multimedia, IEEE Transactions on Systems, Man, and Cybernetics, IEEE Transactions on Professional Communication, among others. He has received research grants and awards from NIH, Google Inc., and Chinese Academy of Sciences. He also serves as senior editor or editorial board member of a number of journals. Hongfang Liu   is currently an Assistant Professor in Department of Biostatistics, Bioinformatics, and Biomathematics (DBBB) of Georgetown University. She has been working in the field of Biomedical Informatics for more than 10 years. Her expertise in clinical informatics includes clinical information system, controlled medical vocabulary, and medical language processing. Her expertise in bioinformatics includes microarray data analysis, biomedical entity nomenclature, molecular biology database curation, ontology, and biological text mining. She received a B.S. degree in Applied Mathematics and Statistics from University of Science and Technology of China in 1994, a M.S. degree in Computer Science from Fordham University in 1998, a PhD degree in computer science at the Graduate School of City University of New York in 2002. Divya Mathew   received the BTech degree in computer science and engineering from Cochin University of Science and Technology in 2005 and the MS degree in information systems from the University of Maryland, Baltimore County in 2008. Her research interests include software engineering and privacy preserving data mining techniques.   相似文献   
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