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171.
One of the main benefits of unsupervised learning is that there is no need for labelled data. As a method of this category, latent Dirichlet allocation (LDA) estimates the semantic relations between the words of the text effectively and can play an important role in solving various issues, including emotional analysis in combination with other parameters. In this study, three novel topic models called date sentiment LDA (DSLDA), author–date sentiment LDA (ADSLDA), and pack–author–date sentiment LDA (PADSLDA) are proposed. The proposed models extend LDA through some extra parameters such as date, author, helpfulness, sentiment, and subtopic. The proposed models use helpfulness in the Gibbs sampling algorithm. Helpfulness is a part of readers who found the review helpful. The proposed models divide the words into two categories: the words more affected by the distribution of subtopic and the words more affected by the main topic. In this study, a new concept called pack is introduced, and a new model called PADSLDA is proposed for sentiment analysis at pack level. The proposed models outperformed the baseline models because according to evaluations results, the extra parameters can appropriately affect the generating process of words in a review. Sentiment analysis at the document level, perplexity, and topic coherence are the main parameters used in the evaluations.  相似文献   
172.

One fundamental issue in cognitive radio mobile ad hoc networks (CR-MANETs) is the selection of a stable path between any source and destination node to reduce the end-to-end delay and energy consumption arisen from route reconstruction. In this way, we analyse the link stability by calculating the link life time that is dependent on failures caused by secondary users’ (SUs) movements and primary users’ (PUs) activities. We propose a joint stability-based routing, link scheduling and channel assignment (SRLC) algorithm in CR-MANETs, which is benefited from considering the link life time, amount of interference imposed on PUs and energy consumption. The proposed algorithm selects a frequency channel/time slot in a way that channel utilization and previous behaviours of SUs and PUs, are taken into account. In the proposed SRLC, the concept of load balancing is applied by avoiding to route packets through SUs with insufficient energy. The effectiveness of the proposed algorithm is verified by evaluating the aggregate interference energy, end-to-end delay, goodput and the energy usage per packet transmission under three different scenarios. The results show our proposed scheme finds better routes compared to the recently proposed joint stable routing and channel assignment protocol.

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173.
Telecommunication Systems - In this paper, load balancing in two-tier cellular networks is investigated. The network under-study is divided into several zones. The first tier of each zone includes...  相似文献   
174.
The authors comment on D. F. Hultsch, C. Hertzog, B. J. Small, and R. A. Dixon's (1999) report of the latest results of the Victoria Longitudinal Study, which are presented as a test of the engagement hypothesis, and on their reanalysis of the data from the Veterans Study (Pushkar Gold et al., 1995), which proposes an alternative model of intellectual function. Differences between the methodologies, variables, and concepts of engaged lifestyle in the 2 studies lead to different tests of the engagement hypothesis and different conclusions. Failure to report specified paths and unjustified assumptions lessen the credibility of the Hultsch et al. model for the Veterans Study data. The authors conclude that their original model, which indicates a small but significant effect of engaged adult lifestyle on the maintenance of intellectual verbal abilities in later life, provides a better explanation of the Veterans Study data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
175.
The purpose of the study was to understand the mechanism of microstructural changes in vegetable‐based meat analogs coated with different batter formulations. A meat analog (substrate) was developed by using vegetable proteins, coated with batters formulated from different combinations of wheat and rice flours, predried at various durations, and subsequently fried. The effect of batter formulation, predrying time, and frying time on spaces occupied by air (porosity, SOA), moisture (SOM), and fat (SOF) in the core region (the meat analog) was studied. The SOA, SOM, and SOF ranged between 8.28–32.72%, 16.73–58.31%, and 16.73–58.31%, respectively. All three fractions of pores in the meat analog were significantly influenced by predrying and frying times; however, batter formulation did not show any significant influence. Batter formulation did not show any significant influence on moisture and fat content within the meat analog. Fat content was not influenced by frying time; and only 90 min predrying made a difference.  相似文献   
176.
177.
Abstract: Project acceleration often results in claims. A LISP program for performing time impact analysis for project acceleration is presented. The program helps the user identify the number of days by which the project can be accelerated and what the user's share will be of the acceleration costs involved. The program analyzes the as-planned, as-built, and utility data files submitted by the user and identifies all delayed, accelerated, added, and canceled (DAAC) activities. It then generates as-planned, as-built, projected, adjusted, owner-accountable, and contractor-accountable schedules. The program performs a compression analysis on the remaining portion of the project. After a consultation session with the user, it apportions acceleration costs between the owner and the contractor in an equitable way. This program is expected to help settle claims.  相似文献   
178.
Analysis of Bridge Condition Rating Data Using Neural Networks   总被引:1,自引:0,他引:1  
Currently bridges are evaluated using either a visual inspection process or a detailed structural analysis. When bridge evaluation is conducted by a visual inspection, a subjective rating is assigned to a bridge component. With analytical evaluation, the rating is computed based on the load applied and the resistance of the bridge component. There have been several attempts to correlate the subjective rating to the analytical rating. The conventional statistical analyses, as well as methods based on fuzzy logic, have not been very successful in providing a clear relationship between the two rating systems. This paper describes the application of neural network systems in developing the relation between subjective ratings and bridge parameters as well as that between subjective and analytical ratings. It is shown that neural networks can be trained and used successfully in estimating a rating based on bridge parameters. The specific application problem for railroad bridges in the commuter rail system in the Chicago metropolitan area is presented. The study showed that a successful training of a network can be achieved, especially if the input data set contains parameters with a diverse combination of intercorrelation coefficients. When the relationship between the bridge subjective rating and bridge parameters was investigated, the network had a prediction rating of about 73%. The study also investigated the relation between the subjective and analytical rating. In this case, the prediction rate was about 43%. Compared with conventional statistical methods and the fuzzy‐logic approach, the neural network system had a much better performance ratio in establishing the relation between the bridge rating and bridge parameters.  相似文献   
179.
In the present study, the Vickers microhardness profile of functionally graded steel austenitic steel produced by electroslag remelting process has been investigated. To produce functionally graded steels, two different slices from plain carbon steel and austenitic stainless steels were spot welded and used as electroslag remelting electrode. Functionally graded steel containing graded layers of austenite may be fabricated via diffusion of alloying elements during remelting stage. Vickers microhardness profile of the specimen has been obtained experimentally and modeled with mechanism-based strain gradient plasticity theory. In this regard, the density of the statistically stored dislocations and that of geometrically necessary dislocations was related to the Vickers microhardness profile of each layer. The experimental results are in good agreement with those obtained from the theory.  相似文献   
180.
This study attempts to fill the gap in ongoing research on the design, optimization, and characterization of ethyl cellulose/hydroxypropyl methyl cellulose-based (EC/HPMC-based) low-saturated oleogel-shortenings by examining their functional effects on physicochemical, and rheological properties in the cupcake and its batter. Thus, the commercial shortening was completely replaced with the oleogel-shortenings in the cake formulation and, then, characteristics of the batter (including specific gravity, emulsion stability, and rheological properties), and cake samples (specific volume, moisture content, and texture properties) were evaluated and compared with each other and the control samples (containing commercial-shortening). In short, the EC-based- and EC/HPMC-based-oleogel-shortenings-batters had more specific gravity and emulsion stability than the control-batter. Liner viscoelastic rang in EC/HPMC-based-oleogel-shortenings-batter, EC-based-oleogel-shortenings-batter, and control-batter was 0.212%, 0.159%, and 0.195%, respectively. EC/HPMC-based-oleogel-shortenings-batter had a more viscoelastic behavior than EC-based-oleogel-shortening-batter after the control-batter (p < 0.05). The results of frequency sweep and dynamic shear tests indicated a higher similarity of the rheological behavior of the EC/HPMC-based-oleogel-shortening-batter with the control-batter. The results of moisture content and texture profile analysis of the cake samples indicated a slower staling in the oleogel-shortenings containing samples, especially EC/HPMC-based-oleogel-shortening type.  相似文献   
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