Improving participation in voluntary activities in Iran is important because increasing productivity among young people, given the country's young population, contributes to community sustainability. Therefore, a better understanding of volunteer motivation in Iranian youth is needed. The Volunteer functions Inventory (VFI) for assessing volunteer motivations has good psychometric properties and is adapted to several languages, but no validated Iranian translation yet exists. The purpose of this study was to investigate the psychometric Characteristics of voluntary functions inventory in members of Iranian Red Crescent Society. Sample size was 595 members of Youth Organization of Iranian Red Crescent Society from 31 provinces and 175 cities of Iran that were selected by multi-stage cluster sampling method and responded to voluntary functions inventory. Data were collected using a demographic sample and voluntary functions inventory (VFI). Confirmatory factor analysis using principal components method was used for data analysis. The results of the present study showed that the voluntary functions inventory had validity and reliability. Also, the factor structure showed that 29 items and 6 factors well assess people's attitudes to volunteering, and the structure of this inventory was well-fitted and confirmed all goodness of fit models. The present study provides the use of the Iranian translation of the Voluntary functions Inventory (6 scales and 29 items) to assess volunteer motivation among young Iranian volunteers.

Different types of contact, including contact between node pairs, any-contact of nodes, and contacts of the entire network, are used to characterize social relations in mobile social networks. Different modes of routing, from the point of view of message delivery semantics, encompass unicasting, multicasting, any-casting, and broadcasting. Studies have shown that using probability Distribution functions of contact data, which is mainly assumed to be homogeneous for nodes, improves the performance of these networks. However, there exists an important challenge in studies on Distributions. A lot of works apply the Distribution of one type of contact to other types. Hence in routing applications, it causes to use of the Distribution of one type of contact for any mode of routing. This study provides a complete solution to model each type of homogeneous contact data Distribution and to use them in different modes of routing. We propose a routing algorithm that uses this new model. Results show that our solution improves the average latency of comparing methods Epidemic, TCCB, and DR about 3.5-times, 30%, and 45%, respectively. It achieves a delivery rate of about 5% and 6%, and average latency about 6% and 8% better than that of DR and TCCB, respectively.

In this paper, an alternative approach in operational modal analysis is presented, utilizing image processing technique and transmissibility functions. Imaging sensors do not impose additional mass on the structure due to their non-contact nature, while transmissibility functions, independent of excitation type, can directly extract mode shapes. The innovation of this research lies in combining these two techniques to record dynamic responses and identify modal properties. To capture the temporal response history from video signals, the block-matching method with sub-pixel accuracy was employed. Validation was conducted by recording the response of the tip of a cantilevered steel beam subjected to impact excitation, using a high-speed camera and a laser vibrometer, simultaneously. The RMSE plots in the time domain and the PSD in the frequency domain indicate high accuracy of this method. Using this approach, the displacement time histories of various points on the structure were extracted from the video signals, and the modal properties, including natural frequencies, damping ratios, and mode shapes, were identified using the transmissibility matrix method. The results obtained from the proposed method were compared with the stochastic subspace identification (SSI) method and analytical solutions. The findings reveal the accuracy of the modal identification approach introduced in this article. The highest relative error in estimating the natural frequencies of the first and second modes, compared to the values from the laser method, are 0.19% and 0.13%, respectively, and in comparison to the analytical values, they are 0.34% and 1.5%, respectively.

یکی از مهمترین ابزارهای نظام توزیع کالاها و خدمات، قراردادهای توزیع است که ازعناصر اساسی حقوق توزیع به شمارمی رود و به سبب پیامدهای ضدرقابتی و انحصارزایی که شبکه های حاصل از این نوع قراردادها –,درعین آثار رقابتی و کارایی اقتصادی غیرقابل انکار خود-به همراه می آورد، مورد توجه روزافزون کشورهای غربی قرار گرفته و دراین میان، قواعد حقوق رقابت با اعمال موازین و اصول آمره خود، نقش تعیین کننده ای در کنترل و هدایت این نوع قراردادها و کاهش مؤثر آثار ضد رقابتی آنها درعین حفظ و ارتقاء کارایی شبکه های قراردادی توزیع در تأمین بهینه نیازهای اقتصادی شهروندان ایفا می کند. این نوشتار که حاصل مطالعه تحلیلی داده های به دست آمده از منابع کتابخانه ای حقوق اتحادیه اروپا و برخی کشورهای اروپایی در زمینه قراردادهای توزیع است و ماهیت، انواع، فلسفه پیدایش و کارکردهای اقتصادی این نوع قراردادها را با هدف توسعه نظام حقوقی ایران، مورد تحلیل و تبیین قرارداده به این نتیجه رسیده است که قراردادهای توزیع در انواع سه گانه خود که به عنوان یک قرارداد معوض تجاری چارچوب عمودی، الحاقی وانحصارزا، توزیع محصول یا محصولات معینی را دریک بازه زمانی معین اما نسبتاً طولانی و یا نامحدود، ساماندهی و تنظیم می کند، در وضعیت کنونی حقوق موضوعه ایران، یک قرارداد نامعین است که می بایست بر اساس قواعد عام مندرج در مواد 44، 45 و 62 قانون اجرای سیاست های کلی اصل 44 قانون اساسی (مصوب 1386) از حیث شروط انحصارزای ضد رقابتی، از سوی شورای رقابت مورد کنترل و نظارت دقیق قرار گیرد و شاید بهتر باشد رژیم حقوقی عام قراردادهای توزیع به عنوان یک عقد معین-شامل تعریف عام، شرایط تشکیل، آثارعام واسباب پایان این نوع قرارداد-باحفظ انعطاف پذیری ازحیث تعیین انواع گوناگون قرارداد مزبور وآثاروشرایط انحلال آن بر اساس توافق طرفین در چارچوب قواعد آمره حقوق رقابت، در قانون تجارت ایران پیش بینی گردد.