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排序方式: 共有1016条查询结果,搜索用时 15 毫秒
1.
Knowledge of the information goal of users is critical in website design, analyzing the efficacy of such designs, and in ensuring effective user-access to
desired information. Determining the information goal is complex due to the subjective and latent nature of user information
needs. This challenge is further exacerbated in media-rich websites since the semantics of media-based information is context-based
and emergent. A critical step in determining information goals lies in the identification of content pages. These are the pages which contain the information the user seeks. We propose a method to automatically determine the content
pages by taking into account the organization of the web site, the media-based information content, as well as the influence
of a specific user browsing pattern. Given a specific browsing pattern, in our method, putative content pages are identified
as the pages corresponding to the local minima of page-content entropy values. For an (unknown) user information goal this
intuitively corresponds to modeling the progressive transition of the user from pages with generic information to those with
specific information. Experimental investigations on media rich sites demonstrate the effectiveness of the technique and underline
its potential in modeling user information needs and actions in a media-rich web. 相似文献
2.
M. K. Tiwari Niraj Sinha Shailendra Kumar Rahul Rai S. K. Mukhopadhyay 《国际生产研究杂志》2013,51(5):1113-1129
In order to protect the environment and regain value added to products, a process known as disassembly has come into the limelight. This process is to be applied to reuse abandoned goods and materials. Manufacturers are being forced to establish disassembly plants and to develop their products' designs so as to maintain the government's dictate to dispose off their products in an environmentally responsible manner. This research presents a cost-based heuristic analysis for a circuit board assembly. Various components of the product and their assembly relationships are represented by a Petri Net diagram. Firing the transitions of the disassembly Petri Net is integrated with cost-based indices to develop an effective disassembly strategy. The methodology discussed here simplifies the decisionmaking process involved in disassembly planning. A comprehensive disassembly process planning system is proposed here and is exemplified by a case study of circuit board assembly. 相似文献
3.
Wireless Personal Communications - Wireless Sensor Networks (WSNs) are used to collect and transmitted the data in various applications from normal to those which requires significant security... 相似文献
4.
Pal Debasish Singhal Rahul Bandyopadhyay Ayan Kumar 《Wireless Personal Communications》2022,124(2):1897-1897
Wireless Personal Communications - 相似文献
5.
Rahul MohanRahul Birari Aniket KarmaseSneha Jagtap Kamlesh Kumar Bhutani 《Food chemistry》2012,132(1):244-251
The antioxidant properties of different extracts of Lagenaria siceraria (bottle gourd) fruit were evaluated. In the process, a new phenolic glycoside (E)-4-hydroxymethyl-phenyl-6-O-caffeoyl-β-d-glucopyranoside (1) was isolated and identified together with 1-(2-hydroxy-4-hydroxymethyl)-phenyl-6-O-caffeoyl-β-d-gluco-pyranoside (2), protocatechuic acid (3), gallic acid (4), caffeic acid (5) and 3,4-dimethoxy cinnamic acid (6). Their structures were elucidated by extensive NMR experiments including 1H-1H (COSY) and 1H-13C (HMQC and HMBC) spectroscopy and chemical evidences. The antioxidant potential of the compound 1 and 2 was tested in different in vitro assay systems such as free radical scavenging assay, 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay, superoxide scavenging activity, reducing power assay and linoleic acid peroxidation assay. 相似文献
6.
Annamalai Jeyakumari Mampuzha Sivadas Rahul Das Jaganath Bindu Chalil George Joshy Aliyamveetil Abubacker Zynudheen 《International Journal of Food Science & Technology》2016,51(7):1578-1585
The effect of an addition of shrimp protein hydrolysate and shrimp powder on the physicochemical properties of extruded snack was studied. Rice flour and cornflour were used as base materials, and extrusion was done using corotating twin‐screw extruder. A mixture response surface methodology was used to study the effect of ingredient mixture on the physical, functional and sensory properties of extrudates. Linear and quadratic mixture response regression model was fitted to the response variables, and it was evaluated using R2 values. Based on the desirability function score, the optimum combination of ingredient was 47.75% rice flour, 38.64% cornflour, 5.95% hydrolysate and 7.67% shrimp protein powder. It was observed that an addition of shrimp hydrolysate more than 5% (7.5%) improved the crispiness. Sensory evaluation revealed that shrimp hydrolysate and shrimp powder can be used at 5–7.5% level for developing protein‐rich extruded products without affecting sensory characteristics. 相似文献
7.
Song C Zaveri RA Shilling JE Alexander ML Newburn M 《Environmental science & technology》2011,45(17):7323-7329
Gas-particle partitioning theory is widely used in atmospheric models to predict organic aerosol loadings. This theory predicts that secondary organic aerosol (SOA) yield of an oxidized volatile organic compound product will increase as the mass loading of preexisting organic aerosol increases. In a previous work, we showed that the presence of model hydrophobic primary organic aerosol (POA) had no detectable effect on the SOA yields from ozonolysis of α-pinene, suggesting that the condensing SOA compounds form a separate phase from the preexisting POA. However, a substantial faction of atmospheric aerosol is composed of polar, hydrophilic organic compounds. In this work, we investigate the effects of model hydrophilic organic aerosol (OA) species such as fulvic acid, adipic acid, and citric acid on the gas-particle partitioning of SOA from α-pinene ozonolysis. The results show that only citric acid seed significantly enhances the absorption of α-pinene SOA into the particle-phase. The other two seed particles have a negligible effect on the α-pinene SOA yields, suggesting that α-pinene SOA forms a well-mixed organic aerosol phase with citric acid and a separate phase with adipic acid and fulvic acid. This finding highlights the need to improve the thermodynamics treatment of organics in current aerosol models that simply lump all hydrophilic organic species into a single phase, thereby potentially introducing an erroneous sensitivity of SOA mass to emitted OA species. 相似文献
8.
Subrata Pandit Pulok K. Mukherjee Kakali Mukherjee Rahul Gajbhiye M. Venkatesh S. Ponnusankar Santanu Bhadra 《Food research international (Ottawa, Ont.)》2012,45(1):69-74
Spices constitute an important group of food which is virtually indispensable in the culinary art. In a view, these spices feared to pose a probability to affect the disposition of conventional pharmaceuticals through inhibition of human cytochrome P450 (CYPs) enzymes. In the present study an approach has been made to evaluate the possible CYP inhibition potential with some Indian spices (Capsicum annuum, Murraya koenigii, Zingiber officinale) and their major bioactive compounds, in combination with pooled microsome; as well as commercially available recombinant human CYP3A4, CYP2D6, CYP2C9 and CYP1A2. Quantification of the bioactive compound was determined through RP-HPLC, in order to standardize the plant material. CYP–carbon monoxide (CYP–CO) complex assay result indicated that all the plants and their bioactive compounds have an interaction potential with CYPs. Fluoregenic assay results indicated that the spice extracts have higher inhibition potential comparing to their single bioactive molecule. The higher enzyme inhibition potential by the extracts may be related to the synergistic effects due to the presence of other constituents in the extract. Capsaicin and C. annuum showed the lowest IC50 value and 6-gingerol and Z. officinale extract showed the highest IC50 value among the entire sample tested. The entire sample showed significantly less (P < 0.001, P < 0.01) interaction potential than known inhibitors. These findings indicate that selected spices are unlikely to cause clinically relevant drug interactions involving the inhibition of major CYP isozymes. 相似文献
9.
10.
S. Rahul Neson Varghese K. Vinod K.M. Devadas Syju Thomas P. Anees M.K. Chattopadhyay S.B. Roy U. Syamaprasad 《Materials Research Bulletin》2011,46(11):2036-2040
MgB2 bulk samples added with nano SiO2 and/or nano diamond were prepared by powder-in-sealed-tube (PIST) method and the effects of addition on structural and superconducting properties were studied. X-ray diffraction (XRD) analysis revealed that the addition caused systematic reduction in ‘a’ lattice parameter due to the substitution of C atoms at B sites and the strain caused by reacted intragrain nano particles of Mg2Si as evinced by transmission electron microscope image. Scanning electron microscopy images showed distinct microstructural variations with SiO2/diamond addition. It was evident from DC magnetization measurements that the in-field critical current density [JC(H)] of doped samples did not fall drastically like the undoped sample. Among the doped samples the JC(H) of co-doped samples were significantly higher and the best co-doped sample yielded a JC, an order of magnitude more than the undoped one at 5 K and 8 T. 相似文献