Evaluating the cutting rate (CR) of stones is important in the cost estimation and the planning of the stone processing plants. This research used regression models to estimate the stones’ CR based on their physico-mechanical characteristics. Stone processing factories in Mahallat City (Markazi province, Iran) were visited, and the CR of diamond circular saws was recorded on six different travertine stones. Next, the stone block samples were collected from the quarries for laboratory tests. Stones’ porosity (n), uniaxial compressive strength (UCS), and Schmidt hammer hardness (SH) were determined in the laboratory as their physico-mechanical characteristics. Correlation relationships of CR with physico-mechanical characteristics were evaluated using simple and multiple regression analyses, and estimator models were developed. Results showed that multiple regression models are more reliable than simple regression for estimating the stones’ CR. The validity of the developed multiple regression models was verified with the published data of one researcher. The findings indicated that these models are accurate enough for estimating the CR of stones. Consequently, the multiple regression models provide practical advantages for estimating the CR and save time and cost during the planning and design of the stone processing factories.

This study aimed to estimate the genetic parameters of body weight traits in Markhoz goats, using B-spline random regression models. The data used in this study included 19549 records collected during 29 years (1992-2021) in Markhoz goat Breeding Research Station, located in Sanandaj, Iran. The model used to analyze data included fixed effects (year of birth, sex, type of birth and age of dam) and random effects including direct additive genetic, maternal additive genetic, permanent environmental and maternal permanent environmental assuming homogeneous and heterogeneous residual variance during the time. Akaike (BIC) and Bayesian (BIC) information criteria were used to compare the models and bspq.4.4.4.4 was selected as the best model. The direct heritability values for birth, 3-month, 6-month, 9-month and 12-month weights were estimated to be 0.14, 0.16, 0.08, 0.28 and 0.26, respectively. Genetic correlation between body weights at birth and 3-month, birth and 6-month, birth and 9-month, birth and 12-month, 3-month and 6-month, 3-month and 9-month, 3-month and 12-month, 6-months and 9-month and 9-month and 12-month were 0.22, 0.38, 0.21, 0.56, -0.26, 0.30, 0.62, 0.86 and 0.77, respectively. The highest phenotypic correlation was between the weight of 9-month and 12-month (0.82) and the lowest correlation was between birth weight and 3-month and 6-month (0.12). The results showed that the 9-month weight is a good criterion for selection in Markhoz goats.

این مقاله تحلیل نتایج حاصل از یک طرح پژوهشی استحصال آب باران از سطوح کوچک (پشت بام ها) است. پشت بام دانشگاه آزاد اسلامی مشهد محل جمع آوری داده هاست. رواناب حاصل از رگبارهای مختلف ریزشی براین سطوح پس از نصب باران سنج معمولی و یک منبع ذخیره (حجم4 متر مکعب) برآورد و رگبارها و رواناب حاصل به مدت دو سال (23/10/86 تا 9/3/88) اندازه گیری شده است. حجم نمونه مشاهد ه ای 35 مورد است. رابطه بین رواناب - بارش با الگوهای رگرسیون بررسی و الگوی مناسب پس از تحلیل باقی مانده ها و آزمون های لازم انتخاب و رواناب حاصل از پشت بام ها به کمک الگوها برآورد شده است. طول دوره آماربرداری کوتاه است. لذا از پنجاه و پنج سال آمار بارش سالانه ایستگاه سینوپتیک مشهد (1951 تا 2005) استفاده شده است. این آمار تحلیل فراوانی شده و نتایج تحلیل فراوانی پنجاه و پنج ساله فوق در دوره های بازگشت ترسالی و خشکسالی به دست آمده است. رواناب پشت بام های این دانشگاه به کمک این تحلیل برای دوره های بازگشت ترسالی و خشکسالی حساب شده است. سطح پشت بام ها و متوسط سالانه رواناب آنها به ترتیب: 18680 مترمربع و 8428 متر مکعب است.