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141.

The new information and communication technologies have changed the trend of communication in all fields. The transportation sector is one of the emerging field, where vehicles are communicating with each other or with infrastructure for different safety and comfort applications in the network. Vehicular ad hoc networks is one of the emerging multi-hop communication type of intelligent transportation field to deal with high mobility and dynamic vehicular traffic to deliver data packets in the network. The high mobility and dynamic topologies make the communication links unreliable and leads to frequent disconnectivity, delay and packet dropping issues in the network. To address these issues, we proposed a road aware geographical routing protocol for urban vehicular ad hoc networks. The proposed routing protocol uses distance, direction and traffic density routing metrics to forward the data towards the destination. The simulation results explore the better performance of proposed protocol in terms of data delivery, network delay and compared it with existing geographical routing protocols.

  相似文献   
142.
Objective: Despite resection with curative intent, a majority of patients with gastric cancer will develop disease recurrence. Postoperative adjuvant chemo-radiotherapy increase the curability of surgery, prevent local recurrence and improve survival. Methods: Between December 2005 and February 2010, 33 patients were eligible for the study, 17 patients were randomly assigned for chemo-radiotherapy (GI) and 16 patients with surgery alone (GII). Patients in GI received chemotherapy (fluorouracil, 425 mg/m2/day, and leucovorin, 20 mg/m2/day, for 5 days) was initiated on day 1 and was followed by chemo-radiotherapy beginning 28 days after the start of the initial cycle of chemotherapy. Chemo-radiotherapy consisted of 4500 cGy of radiation at 180 cGy/day, five days/week for five weeks, with fluorouracil (400 mg/m2/day) and leucovorin (20 mg/m2/day) on the first four and the last four days of radiotherapy. One month after the completion of radiotherapy, two five-day cycles of fluorouracil (425 mg/m2/day) plus leucovorin (20 mg/m2/day) were given one month apart. Results: Grade 3 gastrointestinal toxicity was more common (23.2%) while grade 3 hematological toxicity were (5.8%). Both 3-year survival (53%) and disease free survival (41%) rates were higher in GI than in GII in which they were 43.7% and 31% respectively. Relapse rate was higher in GII (56.3%) than in GI (35.3%). Conclusion: The present study revealed that chemo-radiotherapy after gastric resection in patients with gastric adenocarcinoma improves survival and relapse rates with manageable toxicities. However, studies with larger number of patients are recommended to confirm our results.  相似文献   
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The mass attenuation coefficients(μ/ρ)of a natural material,i.e.,olive peat,were measured at photon energies of 0.059,0.356,0.662,1.17,and 1.332 MeV and compared with those of concrete and Pb.The experimental samples were irradiated with ~(214)Am,~(133)Ba,~(137)Cs,and ~(60)Co point sources using a transmission arrangement.The olive peat samples were obtained from different areas in Jordan,namely Mafraq(sample M),Kerak(sample K),Ajloun(sample A),and Irbid(sample I),and photon energies were measured using a NaI(T1)scintillation detector with an energy resolution of 7.6% at 662 keV.The differences in the μ/ρ of olive peat samples and the calculated μ/ρ of concrete were consistently within 0.7% at photon energies of 0.356-1.332 MeV.This finding indicates that olive peat can be used in radiation applications in the field of medical physics.Finally,the half-value layer(HVL)of the experimental samples was measured,and results were compared with those of concrete and Pb.Pb and concrete exhibited minimal HVL values due to their high density,and the HVL of olive peat revealed lower shielding effectiveness than that of concrete.  相似文献   
146.
Lysine Lipoylation is a protective and conserved Post Translational Modification (PTM) in proteomics research like prokaryotes and eukaryotes. It is connected with many biological processes and closely linked with many metabolic diseases. To develop a perfect and accurate classification model for identifying lipoylation sites at the protein level, the computational methods and several other factors play a key role in this purpose. Usually, most of the techniques and different traditional experimental models have a very high cost. They are time-consuming; so, it is required to construct a predictor model to extract lysine lipoylation sites. This study proposes a model that could predict lysine lipoylation sites with the help of a classification method known as Artificial Neural Network (ANN). The ANN algorithm deals with the noise problem and imbalance classification in lipoylation sites dataset samples. As the result shows in ten-fold cross-validation, a brilliant performance is achieved through the predictor model with an accuracy of 99.88%, and also achieved 0.9976 as the highest value of MCC. So, the predictor model is a very useful and helpful tool for lipoylation sites prediction. Some of the residues around lysine lipoylation sites play a vital part in prediction, as demonstrated during feature analysis. The wonderful results reported through the evaluation and prediction of this model can provide an informative and relative explanation for lipoylation and its molecular mechanisms.  相似文献   
147.
This paper presents a design algorithm for networks with a restoration mechanism that provides end-to-end path protection to a set of demands with specified working routes, where demands must survive one or two failures in optical networks and these failures may occur almost instantaneously. Each of the demands protected from two failures is assigned two restoration routes and restoration wavelengths on a cycle. A demand protected from a single failure is assigned one restoration route and restoration wavelengths on a cycle. These assignments are preconfigured so that switching and wavelength conversions are not needed at intermediate nodes of restoration routes. Splitting of demand across multiple restoration routes upon a failure occurrence is not allowed. The algorithm generates a large number of candidate Path-Protecting Preconfigured Cycles (PP-PCs). A candidate cycle may provide protection to a mix of demands requiring different protection levels, where demands may share under certain conditions restoration wavelengths even if they are exposed to common failure scenarios and have overlapping restoration routes. A near-optimal set of preconfigured cycles is selected from among all candidates, attempting to minimize the total cost of restoration wavelengths while ensuring that each demand is assigned to a single preconfigured cycle. This is achieved by solving a set covering problem followed by deleting duplicate demand assignments and by resolving wavelength assignment conflicts.  相似文献   
148.
Intermediate water (IW) in hydrated bioactive glasses remains uninvestigated. We obtained titanium (Ti)-containing bioactive glasses (BGTs) (Ti at 5%, 7.5% and 10% of the glass system) using the sol–gel technique. Their thermal, physicochemical, and morphological properties, before and after Ti-doping, were analysed using DTA, XRD, FTIR, TEM, and SEM accessorised with EDAX, and size distribution and zeta potential surface charges were determined using a NanoZetasizer. The IW in hydrated BGTs was investigated by cooling and heating runs of DSC measurements. Moreover, the mode of death in an osteosarcoma cell line (MG63) was evaluated at different times of exposure to BGT discs. Ti doping had no remarkable effect on the thermal, physicochemical, and morphological properties of BGTs. However, the morphology, size, and charges of BGT nano-powders were slightly changed after inclusion of Ti compared with those of BGT0; for example, the particle size increased with increasing Ti content (from 4–5 to 7–28 nm). The IW content was enhanced in the presence of Ti. The mode of cell death revealed the effect of IW content on the proliferation of cells exposed to BGTs. These findings should help improve the biocompatibility of inorganic biomaterials.  相似文献   
149.
Many manufacturing environments consist of a final assembly shop that receives components from various feeder shops. Suppose the final assembly shop assembles a mix of products, each requiring varying amounts of different components. Thus, the sequence in which products are assembled imposes time-dependent demands on the feeder shops. Such problems are often found in the assembly of high-tech telecommunications systems and in the assembly of mixed models of automobiles. We develop a variety of models that link the work-in-process inventory in the feeder shop and the finished component inventory to the component production interval and the final assembly sequence. The manufacturing disciplines considered include push, look-ahead and kanban. Feeder shops are assumed to manufacture components continuously, periodically, or at a fixed lot size. Simple performance characteristics of the feeder shop are derived to provide insight into synchronized manufacturing issues and to help evaluate the effect of different final assembly sequences on feeder shops.  相似文献   
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