This article investigates the static stability and mode-shapes of composite laminated beams under varying axial in-plane loads. The kinematic displacement field is described by unified higher-order ...shear deformation theory. Six functions are assumed to describe the distribution of axial in-plane load, which are one-constant function, two-linear functions, and three-parabolic functions. The Hamilton's principle is proposed to get the equilibrium equations of unified composite laminated beams. An efficient numerical differential quadrature method (DQM) is proposed to solve the govern equations. The obtained equations are solved as an eigenvalue problem to find critical buckling loads and their corresponding mode-shapes. The validation studies are compared with published works. Numerical results illustrate effects of in-plane load type, beam thickness, orthotopy ratio, fiber orientations, and boundary conditions on the critical buckling loads. The effect of axial load functions on the buckling mode-shapes is presented for the first time. These effects play very important role on the static stability and mode-shapes of composite beam structures. The proposed model may be important in design of aircraft, civil and ship-building when non-uniform in-plane compressive load is important.
•Investigation of buckling of composite beams under varying axial in-plane loads.•Unified beam theories are exploited in analysis for varying axial load for first time.•Mode-shapes of composite beam under varying axial load is investigated for first time.•Numerical DQM is proposed to solve the govern equations of unified beams.•The model is important in design of aircraft under non-uniform compressive loading.
In Tātic, a modern Northwest Iranian language group,
is a polysemous postposition which has not evolved into an accusative marker, unlike what happened in Modern Persian. Tātic varieties, which ...include all Tāti, Tālyshi and Tātoid dialects spoken in northwest Iran, exploit the postposition
to mark many different case roles. This paper studies the various functions of the postposition
and its variants in this language group. The data for the study have been gathered through fieldwork and interviews with Tāti native speakers as well as through available descriptive grammars. Using the dative semantic-map approach, we show that the main functions that
marks in all Tātic dialects are ‘beneficiary’, ‘reason’ and ‘purpose’. We conclude that because some of the functions of
are not among the semantic roles in the conventional dative semantic map, this needs to be expanded in order to account for the polysemy patterns of
in the Tātic language group.
Software bugs are defects or faults in computer programs or systems that cause incorrect or unexpected operations. These negatively affect software quality, reliability, and maintenance cost; ...therefore many researchers have already built and developed several models for software bug prediction. Till now, a few works have been done which used machine learning techniques for software bug prediction. The aim of this paper is to present comprehensive study on machine learning techniques that were successfully used to predict software bug. Paper also presents a software bug prediction model based on supervised machine learning algorithms are Decision Tree (DT), Naïve Bayes (NB), Random Forest (RF) and Logistic Regression (LR) on four datasets. We compared the results of our proposed models with those of the other studies. The results of this study demonstrated that our proposed models performed better than other models that used the same data sets. The evaluation process and the results of the study show that machine learning algorithms can be used effectively for prediction of bugs.
In this paper, a novel control strategy for subsynchronous resonance (SSR) mitigation using a static synchronous series compensator will be presented. SSR mitigation is obtained by increasing the ...network damping only at those frequencies that are critical for the turbine-generator shaft. This is achieved by controlling the subsynchronous component of the grid current to zero. Using the IEEE first benchmark model, the effectiveness of the proposed control algorithm when mitigating SSR due to torsional interaction and torque amplification effect will be shown.
In this study, a novel robust H∞ output feedback control scheme is presented for discrete-time piecewise affine (PWA) systems in the presence of external disturbance and time-domain constraints. The ...suggested control method is formulated as linear matrix inequalities (LMIs). The designed controllers not only guarantee the stability of the closed-loop systems, but also obtain the disturbance attenuation ability.
Gridded quantitative precipitation estimation (QPE) of high spatial and temporal resolution is now being increasingly used for instance for hydrological modelling. The combination between ...observations from radar data and in-situ rain-gauge measurement is a popular mean to produce QPEs. Since the QPE generated from radar data only is considered to be not satisfactory, some corrections should be introduced in order to achieve better accuracy of the instant precipitation estimation. The correction method that were used were Mean Field Bias Correction (MFB) and static adjustment. MFB was applied by the assumption that the radar estimation was affected by uniform multiplicative error. The static adjustment was applied to correct radar rainfall data through plotting between radar rainfall and rain gauge so that the regression line between radar and rain gauge was approaching one. The purpose of radar QPE corrections was for hydrological modelling applications.
Network traffic associated with video increases sharply, how to choose the interested information for a number of Internet users is challenging. So, technologies and applications related with video, ...such as video search, video fast browsing, video index and storage are in great demand. Behind these technologies and applications, a core problem is how to quickly browse massive video data and obtain the main content of the video. To solve this problem, different key frame extraction algorithms have been proposed. Due to the diversity of video content, different video have different characteristics. So the design of general video key frame extraction algorithm to solve the problem is not the reality. The main trend for the problem is to design the key frame extraction algorithm based on the characteristics of the video itself. In this article, we mainly focus on videos with edited boundaries and shot conversions. Aiming at this kind of video, we have designed and implemented video key frame extraction algorithm based on sliding window, the global feature Gist and local feature point detection algorithm SURF. In this algorithm, we use Gist feature to construct the global scene information of frames, and the SURF keypoint detection algorithm to extract local keypoints as local feature for each frame. Then, shot segmentation based on sliding window and shot merging algorithm is applied to dividing the original video into several shots. After that, we select the most representative frames in each video shot as key frames. Finally we evaluate the result of the algorithm from the subjective and objective perspective. Results show that key frames extracted in the algorithm are of high quality and can basically cover the main content of the original video.
Rak je drugi najvažniji uzrok smrti u našoj zemlji, odmah nakon bolesti srca i krvnih žila. S pretpostavkom porasta incidencije i smrtnosti od raka u idućim godinama, projekcije su da će se znatno ...povisiti i troškovi dijagnostike i liječenja raka, i zbog uvođenja novih dijagnostičkih tehnika i zbog inovativnih lijekova te meto-da liječenja. Posljedično se nameće imperativ što boljeg iskorištavanja financijskih sredstava, raspoloživog osoblja i tehnike, a sve radi osiguranja kontinuiteta prikladne dijagnostike i liječenja. Optimalnim provođenjem dijagnostičkih metoda mogu se spriječiti nepotrebno odugovlačenje obrade, rasipanje financijskih sredstava i nepotrebno opterećenje zdravstvenih djelatnika te skratiti liste čekanja. HDIO je donio ove smjernice radi prevladavanja navedenih problema, vodeći brigu o najvećoj koristi za bolesnika, što bi na kraju trebalo dovesti do racionalizacije i standardizacije dijagnostičkih postupaka u svakodnevnoj kliničkoj praksi. Smjernice bi trebale pomoći da iz cijele palete dijagnostičkih postupaka koji su nam na raspolaganju odaberemo najrelevan-tnije za pojedino sijelo i kliničku proširenost bolesti.
Bistatic coherent MIMO clutter rank analysis Bell, Kristine; Johnson, Joel; Baker, Christopher ...
2015 23rd European Signal Processing Conference (EUSIPCO),
08/2015
Conference Proceeding
The rank of the clutter covariance matrix in a bistatic coherent multiple-input multiple-output (MIMO) radar system with arbitrary planar arrays in both the transmitter and receiver is examined. The ...analysis provides further generalization of "Brennan's rule" results available for linear arrays in monostatic coherent MIMO and bistatic space-time adaptive processing (STAP) systems. We first extend the two-dimensional (2D) monostatic STAP results of Varadarajan and Krolik (VK) to monostatic MIMO systems with planar arrays. We then use the VK bistatic STAP approach and determine conditions under which a four-dimensional (4D) bistatic MIMO system can be modeled as an equivalent 2D monostatic MIMO system, and apply the 2D results. The analytical expressions are validated against the numerically calculated rank of the theoretical clutter covariance matrix.
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