Dynamic characteristics of students’ communicative behavior in social networks

Dynamic characteristics of social networks users' behavior represent the toolkit for diagnosing the character and orientation of cyber communication. This study aims to analyze the communicative behavior of youth after transitioning directly from direct communication to communication via technology for the purpose of defining opportunities and determining manipulation potential on communicants. Sixty-two (62) active participants of social networks were selected to answer the questions of the questionnaire. Further, on the grounds of the provided statistics of their accounts, quantitative characteristics of dynamics of cyber communication of participants' communicative behavior were analyzed using descriptive statistics and r-criterion of Spearman rank correlation. From the results, decrease in the level of intellectual communication of the youth in cyberspace provides a high level of the youth manipulative availability in social networks. Hypotheses about measurability of dynamic characteristics of cyber communication, as well as the communication vector shift from small groups into big ones were confirmed. Keywords: dynamic characteristics of communication, cyber communication, social networks, meme, repost, post.

Design and optimization of multi user OFDM orthogonal chaotic vector shift keying communication system

This paper study and present, power allocation strategy on sub-carriers of multiuser OFDM employed for orthogonal chaotic vector shift keying (MU OFDM-OCVSK) over multipath frequency selective fading channels. firstly, the MU OFDM-OCVSK system is modeled with power allocated on reference and information bearing subcarriers. Then, the computed bit error rate equation of the power allocation MU OFDM-OCVSK system is derived. The optimal power allocation strategy on subcarriers is obtained using convex optimization. Finally, compared with the traditional MU OFDM-DCSK and MU OFDM-OCVSK without power allocation system the proposed system can achieve an excellent BER performance under multipath Rayleigh fading channels. Numerical and Simulation results emphasize the remarkable features of the proposed optimal power allocation strategy.

POLYPARAMETRIC BLOCK CODING

The principles of poly-parametric information coding have been considered. The methods for developing poly-parametric codes have been presented. It is shown that the protection of block codes from channel interference using check patterns can be developed by a mono- or poly-parametric method. A special type of block codes has been presented, the check patterns of which are formed on the basis of their neighbours, which are functionally related to the given code combination. Such codes have been called poly-parametric. Binary poly-parametric ring codes, the check patterns of which are designed to detect and correct channel errors, are developed using the properties of Galois fields and on the basis of the vector shift indicators of the codewords. To obtain digital poly-parametric block codes, the properties and features of the normalized natural sequence are used. It is shown that each codeword of a binary block code can be represented as a certain positive integer in the decimal number system, which is an element of the natural sequence. Its elements on an interval that equals the norm acquire a functional dependency.

Fiducial-based image-guided SBRT for pancreatic adenocarcinoma: Does inter-and intra-fraction treatment variation warrant adaptive therapy?

Purpose Variation in target positioning represents a challenge to set-up reproducibility and reliability of dose delivery with stereotactic body radiation therapy (SBRT) for pancreatic adenocarcinoma (PDAC). While on-board imaging for fiducial matching allows for daily shifts to optimize target positioning, the magnitude of the shift as a result of inter- and intra-fraction variation may directly impact target coverage and dose to organs-at-risk. Herein, we characterize the variation patterns for PDAC patients treated at a high-volume institution with SBRT. Methods We reviewed 30 consecutive patients who received SBRT using active breathing coordination (ABC). Patients were aligned to bone and then subsequently shifted to fiducials. Inter-fraction and intra-fraction scans were reviewed to quantify the mean and maximum shift along each axis, and the shift magnitude. A linear regression model was conducted to investigate the relationship between the inter- and intra-fraction shifts. Results The mean inter-fraction shift in the LR, AP, and SI axes was 3.1 ± 1.8 mm, 2.9 ± 1.7 mm, and 3.5 ± 2.2 mm, respectively, and the mean vector shift was 6.4 ± 2.3 mm. The mean intra-fraction shift in the LR, AP, and SI directions were 2.0 ± 0.9 mm, 2.0 ± 1.3 mm, and 2.3 ± 1.4 mm, respectively, and the mean vector shift was 4.3 ± 1.8 mm. A linear regression model showed a significant relationship between the inter- and intra-fraction shift in the AP and SI axis and the shift magnitude. Conclusions Clinically significant inter- and intra-fraction variation occurs during treatment of PDAC with SBRT even with a comprehensive motion management strategy that utilizes ABC. Future studies to investigate how these variations could lead to variation in the dose to the target and OAR should be investigated. Strategies to mitigate the dosimetric impact, including real time imaging and adaptive therapy, in select cases should be considered.

A New Passive Islanding Detection Solution Based on Accumulated Phase Angle Drift

The existing passive methods for islanding detection are mainly based on the detection of voltage and frequency deviation after islanding, using protections such as voltage vector shift (VVS) and rate of change of frequency (ROCOF). Although there are reported issues with these passive methods such as inherent non-detection zones and nuisance trips, utilities prefer the passive methods due to the low cost and simplicity of deployment. In this paper, one composite passive islanding detection method is presented. It tracks the voltage phase angle, the system frequency, and ROCOF every power cycle. If three phase voltage vectors shift in the same direction and the rotated angle values are balanced, the calculation of the accumulated phase angle drift (PAD) will be initiated. This calculation continues until the ROCOF measurement is below the ROCOF setting threshold. If the accumulated phase angle drift reaches the set angle threshold, the condition for islanding is claimed. The performance of this composite method is verified under different scenarios based on Matlab Simscape multidomain physical systems and practical waveforms recorded from sites. Although there are still non-detection zones, this composite PAD solution has better sensitivity than existing VVS and ROCOF methods and is stable under external system faults.

Evaluasi Kinerja Bagan Kendali Fm Pada Proses Short-Run

<p><em>The manufacturing production process that is currently trend is short-run. Short-run process is a job shop and a just in-time. These causes the process parameters to be unknown due to unavailability of data and generally a small amount of product. The control chart is one of the control charts which designed for the short run. The procedure of the control chart follows the concept of succesive difference and under the assumption of the multivariate Normal distribution. The sensitivity level of a control chart is evaluated based on the average run length (ARL) value. In this study, the ARL value was calculated based on the shift simulation of the average vector by recording the first m-point out of the control limits. The average vector shift simulation of the target () is performed simultaneously with the properties of a positive shift (=+ δ). Variations of data size and many variables in this study were m = 20, 50 and p = 2, 4, 8, respectively. Each scheme (a combination of δ, m and p) is iterated 250,000 times. The simulation results show that for all schemes when both parameters are known ARL₀≈ 370. But, when parameters are unknown, ARL₁ turn to smaller. This conclusion also implied when the number of p and n are increased, it reduce the sensitivity of the control chart.</em></p>