Using the soft fingers increases stability and dexterity in object grasping and manipulation. This is because of the enlarged contact interface between soft fingers and object. Although slippage phenomenon has a crucial role in robust grasping and stable manipulation, in the most of previous researches in the field of finger manipulation, it is assumed that the slippage between finger and object does not occur. In this paper, slippage dynamic modeling in object grasping and manipulation using soft fingers is studied. Because of the enlarged contact interface between soft fingers and object, a frictional moment along with tangential frictional force and normal force is applied on the contact interface. Therefore, a novel method for dynamic modeling of planar slippage using the concept of Friction Limit Surface is presented. In this method, equality and inequality relations of different states of planar contact is rewritten in the form of a single second-order differential equation with variable coefficients. These coefficients are determined based on the slippage conditions. This kind of dynamic modeling of contact forces can be used for designing the controllers to cancel the undesired slippage. The method is used in study of slippage analysis of a three-link soft finger manipulating a rigid object on a horizontal surface. In order to increase the accuracy of dynamic modeling of soft finger, dynamics of soft tip is integrated with the dynamic of finger linkage. Dynamic behavior of this system is shown in the numerical simulations.

Cylindrical Frictional Damper (CFD) is a new revolutionary frictional based mechanical damper. Unlike the other types of frictional dampers, CFDs do not utilize bolts to produce friction between contact surfaces. These dampers consist of two main parts, the inner shaft and the external cylinder. These two parts are assembled such that one is shrink-fitted inside the other. In this investigation, seismic response of steel structures equipped with CFDs is studied. Special attention is given to the sensitivity of the seismic response to the value of the slippage load. To do so, the optimum slippage load of the structure (the slippage loads which results in minimum displacement response) is obtained for various seismic excitations. The seismic response of the structure is obtained for various slippage loads in the range of plus and minus %20 of the optimum slippage load. Moreover the seismic performance of steel structures equipped CFDs is investigated using non-linear time history analyses. The results show that value of the optimum slippage load is completely dependent to seismic excitation. It is further shown that if the slippage load has a difference up to 20% from its optimum value, the maximum displacement response can increases up to 35%, however, it is still less than the maximum displacement response of the frame without CFDs. It was also shown that CFD can significantly improve the performance of steel structures subjected to earthquake loads.

There have been many researches on object grasping in cooperating systems assuming no object slippage and stable grasp and the control system is designed to keep the contact force inside the friction cone to prevent the slippage. However undesired slippage can occur due to environmental conditions and many other reasons. In this research, dynamic analysis and control synthesis of a cooperating system, considering slipping conditions are performed. Equality and inequality equations of the frictional contact conditions are replaced by a single second order differential equation with switching coefficients in order to facilitate the dynamical modeling and control synthesis. Using this new modeling of friction, a conventional approach in grasping control is modified and presented to control any undesired slippage of the end-effectors on the object.

Concrete-filled steel tube (CFST) beams are widely used in civil engineering, especially for bridges and tall buildings, because of their strength, stiffness and durability. Good bonding at their interface is essential for ensuring that steel and concrete can work well together. However, if interfacial slippage does occur it not only hinders the plasticity of a beam’s performance in full section but also weakens its strength and stiffness. To study the mechanism of slip occurrence and its impact, eight prestressed CFST rectangular beams were tested under monotonic loading. Slippage was measured during the entire loading procedure. Based on the elasto-plastic theory, a nonlinear finite element model, considering slippage is developed in this paper. The results show that slippage occurred when the concrete began to crack. This plays an important role in the overall performance of a beam after the steel has yielded. The maximum slip occurred near the section of quarter-span. To some extent, the slip curves generated by this model agreed with the test results, and it could be used to predict the bending capacity of prestressed CFST beams.

The purpose of this study was to examine the effectiveness of self-encouragement training on cognitive slippage and fear of negative evaluation of female students. This research was conducted as a semi-experimental design with pretest-posttest and control group. The subjects wre 30 students (15 participants for each group) selected by multi-stage cluster sampling method. The experimental group received 8 sessions of self-Encouragement training, meanwhile the control group did not receive any training. At the end of the training, post-test was taken from all participants. Instruments of the study included Cognitive Slippage Scale (Miers, & Raulin, 1985) and Fear of Negative Evaluation Questionnaire (Watson, & Friend, 1969). The results of MANCOVA showed that self-encouragement training reduced the cognitive slippage and fear of negative evaluation. According to the effectiveness of this training in decreasing cognitive slippage and fear of negative evaluation, it can be considered practical for students.

Performances of electronic and mechanical draft control systems on a MF399 tractor were the objectives of the study to be evaluated and compared under field conditions. Hence, the effects of two draft control systems (mechanical and electronic) under four ground speed levels and three set values of draft levels on rear wheel slippage, fuel consumption, compressive force within the top link and tillage depth in a sandy loam soil were assessed by conducting an experiment of a randomized complete block design. Results obtained from the statistical analysis revealed that there was a significant decrease in mean values of slippage as well as in fuel consumption when the system equipped with electronic control as compared with the mechanical one. It was found that the compressive force within the top link as well as mean depth value were significantly lower with the electronic control system resulting in a decrease in wheel slip as well as in fuel consumption. The results also revealed that fuel consumption decreased with increasing ground speed and decreasing the set values of draft. The mean value of slippage in electronic control system for all the treatments was recorded less than 20%, while with the mechanical system it reached level as high as 39%.

Microsatellites or simple sequence repeats (SSRs) are very effective molecular markers in population genetics, genome mapping, taxonomic study and other large-scale studies. Variation in number of tandem repeats within microsatellite refers to simple sequence length polymorphism (SSLP); but there are a few studies that are showed SSRs replication slippage may be occurred during in vitro amplification which are produced ‘stutter products’ differing in length from the main products. The purpose of this study is introducing a reliable method to realize SSRs replication slippage. At first, three unique primers designed to amplify SSRs loci in the great gerbil (Rhombomys opimus) by PCR. Crush and soak method used to isolate interesting DNA bands from polyacrylamide gel. PCR products analyzed using by sequencing methods. Our study has been shown that Taq DNA polymerase slipped during microsatellite in vitro amplification which led to insertion or deletion of repeats in sense or antisense DNA strands. It is produced amplified fragments with various lengths in gel electrophoresis showed as ‘stutter bands’. Thus, in population studies by SSRs markers recommend that replication slippage effects and stutter bands have been considered.

Adhesion level for the proper running of rail wheelset on track has remained a significant problem for researchers in detecting slippage to avoid accidents. In this paper, the slippage of rail wheels has been observed applying forward and lateral motions to slip velocity and torsion motion. The longitudinal and lateral forces behavior is watched with respect to traction force to note correlation based on the angle of attack. The deriving torque relation with tractive torque is watched to check slippage. Coulomb’s law is applied in terms of tangential forces to normal forces owing to creep co-efficient and friction to get the adhesion. Nadal’s limiting ratio is applied to escape from wheel climb and derailment from track depending upon wheel profile and flange on straight path and curves.

In this research, draft requirement of subsoiler tine plus fuel consumption, slippage, drawbar power, traction efficiency and overall energy efficiency of MF399 and JD3140 tractors at four speeds of 1.8, 2.3, 2.9 and 3.5 km/h and two depths of 40 and 50 cm were compared. Tractor type, speed and depth plus interaction effects had a significant effect on all parameters other than draft and drawbar power. Generally, JD3140 showed a better performance as the increase in speed from 1.8 to 3.5 km/h caused the increase of draft, fuel consumption, slippage, drawbar power and overall energy efficiency in two depths of 40 and 50 cm of 7, 4, 23, 108.3 and 89%, respectively but caused the decrease of traction efficiency of 13.8%. Furthermore, 10 cm increase in depth caused the increase in draft, fuel consumption, slippage and drawbar power of 21.3, 31.6, 20.6 and 21.4%, respectively but caused the decrease in traction efficiency and overall energy efficiency of 9.7 and 25%, respectively. The results of optimization of studied parameters using response surface methodology (RSM) show that depth of 42.9 cm and speed of 2.4 km/h resulted in the optimized condition about the performance of the tractor-subsoiler set.

Turning to the narrations of Asbab al-Nuzul is a clear example of the commentator's attempt to be in the conditions of the revelation of the verses of the Holy Qurʾān in order to achieve a correct and comprehensive understanding of the concepts of the verses. Excessive trust in the Asbab al-Nuzul  and neglecting its damages can also cause slippages in the opinions of commentators. In this study, we intend to review the evidence of the wrong understanding of the verses of the Qurʾān in the first three centuries of the Hijra, and the cases of slippages caused by trusting the narrations that caused the downfall from an intra-religious point of view. In the first step, we will define the causes of descent and state its benefits and harms. Then we will review the opinions of the commentators of the first three centuries of Hijra in using the narrations of the causes of descent, and examples of incorrect usage. It is possible to recognize three categories of slippages in understanding the causes of revelation: incorrect determination of exceptions, unjustified claims of abrogation in the Qurʾān, and mixing criteria for distinguishing Meccan and Madani suras.