فهرست مطالب حامد تقی زاده

The purpose of this research was to investigate the mediating role of social undermining in the relationship between toxic leadership and organizational indifference. The research method was applied in terms of objective and correlational in terms of descriptive method. The statistical population of the research was the employees of the fiscal affairs organization of East Azarbaijan province with the number of 812 people, from this population, the desired sample number was obtained through the Morgan table, the number of 291 people. which is selected by stratified random sampling method. standard questionnaires data collection tool; The toxic leadership of Ashmit (2008), Duffy's Social Attrition (2002) and the Organizational Indifference Questionnaire of Danai Fard et al. Face validity and CVR index were used to determine validity, and Cronbach's alpha method was used to determine reliability. The value of alpha for toxic leadership, organizational indifference and social undermining was obtained as 0.894, 0.821 and 0.858 respectively. The analysis of research data has been done through path analysis and structural equation model using Lisrel software. The results of the research have shown that toxic leadership has an effect on social undermining with an effect intensity of 0.361 and on organizational indifference with an effect intensity of 0.276. Also, social undermining has a mediating role in the relationship between toxic leadership and organizational indifference with an effect intensity of 0.173. Social wear also with the effect intensity of 479/. It affects organizational indifference.

The safety of dams is directly related to the sufficiency of spillway capacity. Most dam failure occurs due to overtopping when the discharge capacity of the spillway was not sufficient. The safe operation of the spillway, under abnormal conditions, is an essential factor in the safety of dams. According to reports released by the International Committee on Large Dams, about one-third of dam failures stem from inadequate spillways. Owing to this sensitivity, the spillway must be designed and constructed as a strong, reliable, and highly productive structure that can be ready for operation at any time. Nonlinear weirs which can be seen in various forms in the plan are economical structures to increase the discharge capacity in a limited width. These weirs have a higher discharge capacity in the same hydraulic head and width. Due to the hydrodynamic complexities of the flow in nonlinear weirs, a general analytical method has not been developed yet in the literature to estimate the discharge capacity of this type of weirs. Usually, the discharge capacity of any nonlinear weir is obtained through various experimental investigations. In this research, a general method is presented for estimating the discharge capacity of nonlinear spillways.

The EDA method is based on nonlinear weir discharge analysis using energy and discharge equations for discrete elements of the solution domain (weir crest in the plan). On the other hand, due to the specific behaviors that occurred in nonlinear weirs (disturbed zone) which have a tangible effect on their discharge capacity, these effects have been taken into account. The geometry of the weir in the plan is the desired solution domain, which is divided into small elements and the corresponding equations in each element have been analyzed. The disturbed zone may also form at the junction of the weir crest to the sidewalls. This phenomenon reduces the discharge capacity, especially at high hydraulic heads. To apply the impact of this phenomenon on the discharge capacity of the affected elements, the relationships and results of the past works could be used. The system of differential equations for each element is solved following the discretization of the solution domain. Thus, the flow discharge past each element is found. Thereafter, the disturbed zones are identified and their reduction effects on the flow discharge of the elements are considered estimating the reduction factors of elements. Finally, the total discharge of non-linear weir will be obtained by integrating over the entire solution domain. To achieve this goal, a computer program is developed using the MATLAB programming language to code the above-mentioned steps.

This method is based on elementary analysis of nonlinear weirs, which calculates the discharge capacity of these weirs by solving energy and discharge equations for each element and correcting the effects of disturbed zones. For evaluating the performance of the proposed method, laboratory results performed on oblique and trapezoidal labyrinth weir have been used. Results show that the accuracy of the EDA model for calculating the discharge capacity has been in the error range of 12% and 20%, respectively. Also, the results of the laboratory model of the rehabilitation project of the Millsite dam spillway (arc labyrinth weir) have been used to investigate the performance of the proposed method in complex geometries. The EDA model with a maximum error of 15% had a satisfactory prediction of the discharge capacity of the Millsite dam weir.

Due to the unique characteristics and increasing application of nonlinear spillways in dams and other hydraulic structures, a general method for analyzing the discharge capacity of these structures can play an important role in design phases. One of the most important applications of nonlinear weirs is in dams where they are revised as rehabilitation projects to increase the capacity of the spillway overpass or increase the volume of the dam reservoir. Due to the hydrodynamic complexity of the flow in nonlinear weirs, no general method has been proposed for their discharge analyses and has often been investigated by laboratory models. In this research, a general method for analyzing nonlinear weirs discharge is presented. To ensure the performance of the EDA method, the laboratory model of oblique and trapezoidal labyrinth weir (at different scales) that studied has been used. The results show that the proposed method has good accuracy in estimating the discharge capacity of oblique and trapezoidal labyrinth weirs. The Millsite Dam spillway, which has one of the notable rehabilitation projects, was also investigated. The results show that the proposed method is relatively better in estimating the discharge capacity of the Millsite Dam spillway over other methods.

Nonlinear weirs are among the hydraulic structures that, despite their great importance and application, so far, no general method for estimating their discharge capacity has been accomplished. Laboratory or numerical modelling is commonly used to achieve nonlinear weir discharge capacity. It should be noted that employing the design equation from one geometric family of nonlinear weirs to another is impractical. The utilization of numerical or laboratory models in the preliminary stages of the design of these structures is a time and cost-consuming process, which is highlighted by the variety of nonlinear weir geometry. In this research, a general method for estimating the nonlinear weirs discharge capacity is presented. The proposed method analyzes nonlinear weir discharge capacity using energy and discharge equations for discretized solution fields. Furthermore, the local submergence in nonlinear weirs, which has a tangible effect on their discharge capacity, has been corrected. Results of laboratory models performed on the oblique weir, arced labyrinth weir, and Isabella dam weir have been used to evaluate the efficiency of the proposed method. The proposed method with high correlation and accuracy has estimated the discharge capacity of these weirs. The maximum error observed was 12 percent for the oblique weir,15 percent for the arced labyrinth weir, and 15 percent for the Isabella Dam weir.

Three-sided spillways are one of the important dam's outlet works that despite their hydraulic limitations, selected as the best option in storage dam under special topographical conditions. Considerable energy losses, the flow high turbulences, and applying great fluctuations shock on walls and bed of the side channel are the hydraulic conditions that must carefully considered in these spillways. In this study, the three-dimensional flow filed of U-shaped spillway and end-sill of the side channel are simulated using Flow3D and the effect of flow turbulences have been modelled by RNG closure. Comparison of the numerical and experimental results revealed that this model with RNG closure has capable to carefully simulate the turbulence flow field on these structures. The effect of making stepped the ogee profile of the three-sided spillway on flow depth and dynamic pressure fluctuations has been numerically evaluated; the non-dimensional turbulence index has been used to investigate the fluctuations of the dynamic pressure. The results revealed making stepped the ogee profile causes to reduce the encounter of the side overfalls, and to increase the flow depth in the side channel, in which this lead to considerable decrease in pressure fluctuation intensity. Three-sided spillways are one of the important dam's outlet works that despite their hydraulic limitations, selected as the best option in storage dam under special topographical conditions. Considerable energy losses, the flow high turbulences, and applying great fluctuations shock on walls and bed of the side channel are the hydraulic conditions that must carefully considered in these spillways. In this study, the three-dimensional flow filed of U-shaped spillway and end-sill of the side channel are simulated using Flow3D and the effect of flow turbulences have been modelled by RNG closure. Comparison of the numerical and experimental results revealed that this model with RNG closure has capable to carefully simulate the turbulence flow field on these structures. The effect of making stepped the ogee profile of the three-sided spillway on flow depth and dynamic pressure fluctuations has been numerically evaluated; the non-dimensional turbulence index has been used to investigate the fluctuations of the dynamic pressure. The results revealed making stepped the ogee profile causes to reduce the encounter of the side overfalls, and to increase the flow depth in the side channel, in which this lead to considerable decrease in pressure fluctuation intensity. Three-sided spillways are one of the important dam's outlet works that despite their hydraulic limitations, selected as the best option in storage dam under special topographical conditions. Considerable energy losses, the flow high turbulences, and applying great fluctuations shock on walls and bed of the side channel are the hydraulic conditions that must carefully considered in these spillways. In this study, the three-dimensional flow filed of U-shaped spillway and end-sill of the side channel are simulated using Flow3D and the effect of flow turbulences have been modelled by RNG closure. Comparison of the numerical and experimental results revealed that this model with RNG closure has capable to carefully simulate the turbulence flow field on these structures. The effect of making stepped the ogee profile of the three-sided spillway on flow depth and dynamic pressure fluctuations has been numerically evaluated; the non-dimensional turbulence index has been used to investigate the fluctuations of the dynamic pressure. The results revealed making stepped the ogee profile causes to reduce the encounter of the side overfalls, and to increase the flow depth in the side channel, in which this lead to considerable decrease in pressure fluctuation intensity.

Chalcolit hic and Bronze Ages are among the most important eras in prehistoric periods of Iran; they serve different cultural data, such as, pottery, architectures, burial, etc. For instance, potteries from Chalcolit hic are buff in surface and use different geometrical mot ifs; whereas, in Bronze Age, we see sudden changes in pottery evidences. In this era, the tradit ion of buff wares had abolished and black-gray ones wit h carved designs occupied the wide range. This cultural difference followed by pottery variet ies have been well ident ified in cultural layers of the most parts of the Iran, especially in northwest areas. In respect with the cultural differences of the area and the properties of Bronze whether they have been derived from new Chalcolit hic culture or new works give evidence of a newly arrived nat ion/culture, there were advent of debates. But in spite of existed disagreement on the case as well as on the unsolved issues between the two eras, it seems that using experimental methods might provide so me responses to all of them. Current study aimed to invest igate the potsherds obtained from Chalcolit hic, and Bronze layers by studying the petrographic of Kul Tappeh at Hadishahr in northwest of Iran, this study attempts to find some informat ion about the soil used in them and their native status. Kul Tepe is a mult i-period tell, about 6 ha in extent and rising 19 m above the surrounding land. The site was originally discovered by an expedit ion in the province of East Azerbaijan in 1968 under the supervision of Kambakhsh Fard, and was later reported by other authors such as Edwards, Kliess, Kroll and Omrani as well. Kul Tepe is located precisely in the northwestern corner of Iran, which is the gateway between the Southern Caucasus and northwestern Iran. Kul Tepe is located next to a broad valley, at the center of the highlands and at the crossroads of major routes linking the Iranian plateau to Anatolia and the Caucasus to Northern Mesopotamia. The first season of excavat ion at Kul Tepe were carried out from June to August in 2010. Because of the huge quantit y of material and deposits at Kul Tepe, the site needs mor e research and excavat ion to better understand the cultural situation in the region. The second season ofexcavat ion was from August to October 2013 in order to answer certain quest ions about the region and extend the studied areas. Ten characterist ic potsherds (5 for each era) from Late Chalcolit hic and Early Transcaucasia culture (Kura-Araxes) were studied by thin section microscopic (petrographic) method. These potsherds had been obtained during the excavat ions on Kul Tepe. Due to obtained result s as wel l as external heterogeneit ies in the two era's potsherds texture, we will find other significant differences among them, including their fabric and texture type. Dominant texture in the potsherds of the Chalcolit hic is of silt or tiny crystals, where as that of Bronze are coarse and puffery. Yet, no one found any volcanic glasses in the potsherds of the Chalcolit hic, whereas potsherds of the other era have volcanic glasses as well as crescent and circle-like pieces. Wit h due attention to the area's geology, fishy sedimentation basin, volcanic stones, pyroclastic stone, calcareous stones, and … existed in the area, one could clearly state that origin of the Bronze potsherds is local; because, unexceptionally some pieces of volcanic or pyroclastic stones will be seen in all of them.

Multidimensional spillways are important hydraulic structures for regulating water level and flow in canals, rivers and reservoirs. The main hypothesis for the development is to increase the conveyance capacity through the spillway crest length at a given width. Finding an appropriate geometry has always been an important issue for designers in achieving maximum water productivity of hydraulic structures. In this study, several plans were simulated numerically considering effective length of spillway crest. Results showed that the highest reduction in the effective length of spillway crest occurs for plans with greater interference area at normal and lateral flows. Also, spillway model No. 5 was recommended as a sufficient plan in terms of flow capacity because of having just one interference area for normal and lateral flows and insignificant compaction during falling streams due to long lateral arms.

Three-side spillways are one type of dam outlets that despite of their hydraulic limitations and construction problems, under specific topographical conditions selected as one of the best options in storage dams. Considerable energy losses, great turbulence and hard stroking on bed and walls of lateral canal are some of undesirable hydraulic features of these spillways. Due to the complexities of fluid flow and the impact of scale, physical models do not provide a clear understanding of the physics governing the flow. In the complex flow and structures, is necessary to be considered, the laboratory studies, along with the numerical studies. In this study, Three-dimensional flow field in the three-side spillway and the end sill, have been investigated by using FLOW-3D software with finite volume method and RNG(k-e) turbulence model. Comparison of numerical results with experimental data showed that this model have a good ability to prediction three-dimensional flow pattern over this kind of spillways.