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Hydraulic jump occurred widely in most of hydraulic structures, such as spillways in high dams, downstream ‎weirs and sluice gates, where is high velocity, the condition of occurrence of a hydraulic jump is to change flow suddenly from ‎supper critical flow (low depth with high velocity) to subcritical flow (high depth with a low velocity). Stilling basin must be designed perfectly to ensure efficient operating over a wide range of flow. Additional devices may be used to ‎stabilize the jump, reduce the length and height of the jump and increase the energy dissipation. ‎‎ Baffle blocks one of these devices which used to stabilize the jump and dissipate energy as a result of impact action. Baffle block ‎used with different shapes such as cubic and trapezoidal (trapezoidal shape in section), the cubic shape is effective when the best ‎dimensions of height, width, spacing, and the best location in the basin were used. United States Department of the Interior Bureau ‎of Reclamation (USBR) recommended that the corners of baffle block must be not be rounded because the corners are effective in ‎producing of eddies which help in energy dissipation. Previous studies showed that, the model of baffle blocks which have an ‎ability to circulate the jet of water in the vertical transverse direction behave best than others for dissipation of energy, also the ‎rotation in jet of water prevents the jump action to the extent, in this case there is a complete energy dissipation and reduction in the ‎stilling basin length.‎However, an insufficient number of studies on gabion baffle blocks and gabion end sill have been developed more recently ‎compared with ‎studies on fixed baffle blocks and fixed end sill.‎ Also, another insecurity that exists for the baffle blocks of stilling ‎basin is cavitation around them, which can be reduced if gabion baffles are used due to changes in the flow pattern conditions.‎In this research a hydraulic jump stilling basin equipped with baffle blocks and end sill in two condition was to be tested in ‎laboratory to determine the dissipation and other characteristics of hydraulic jump for various type of baffle blocks and end sill. In ‎one condition the bed and baffle blocks and end sill of stilling basin were rigid and in the other condition the bed was rigid but the ‎baffle blocks and end sill were permeable and were constructed with gabion by different porosity.‎ Experiments were carried out at the Hydraulic Laboratory of the Faculty of Engineering, Bu-Ali Sina ‎University of Hamedan in a flume 15 m long and 0.6 m wide and 0.6 m deep. In this research a hydraulic jump stilling basin ‎equipped with baffle blocks and end sill in different conditions. The bed of stilling basin was rigid but various type of baffle blocks ‎and end sills with different permeability were used. The concrete was used for constructing rigid baffle blocks and rigid end sill and ‎gabion was used for constructing baffle blocks and end sill by 30, 45 and 60 percent permeability. Sand and gravel were used to ‎make permeable baffle blocks and end sills. A sluice gate was used for creating of flow by high velocity and low depth to create ‎high Froude Number. The sluice gate was placed in 8 meters from beginning of flume. The tailwater depth was adjusted by a ‎butterfly gate at the end of flume.‎The Baffle blocks and end sill dimension and positions were according to USBR III recommendations. All experiments were done ‎in three Froude numbers of 3.8, 4.3 and 5.1. The flow depth was measured on a grid 5 cm5 cm using a depth gauge with an ‎accuracy of 0.1 mm. ‎ After measuring the flow depth, the parameters of conjugate depth ratio, relative depth, relative ‎length, relative energy loss and water surface profile for hydraulic jumps formed in the stilling basin with rigid floor and baffle ‎blocks and end sill with different porosities 0, 30, 45% and 60% were calculated. Then the changes of these parameters were ‎investigated according to the Froude number of the inlet flow to the stilling basin. Advantages shows that by increasing the porosity ‎of baffle blocks and end sill. The results show that by increasing the porosity of the baffle blocks and end sill, the ratio of conjugate ‎depths decreases and the amount of this decrease increases with increasing the Froude number of the inlet flow to the stilling basin. ‎So that for Froude number equal to 5 and porosity 60% of baffle blocks and end sill, this reduction reaches about 40%. The change ‎in the relative depth and relative length of the hydraulic jump has a similar trend to the conjugate depth due to the increased porosity ‎of the baffle blocks and the end sill. For the Froude number equal to 5 and the porosity to 60% of the baffle blocks and the end sill, ‎the relative length and relative depth of the hydraulic jump are reduced by about 77% and 22%, respectively. While the relative ‎energy loss increases with increasing the porosity of the baffle blocks and the end sill and reaches about 45% for Froude number ‎equal to 5 and porosity 60%. ‎ In this study, in addition to rigid baffle blocks and rigid end sill, the permeable baffle blocks and permeable end ‎sill with porosities of 30 45 and 60 percent were used in the USBR type III stilling basin. Then the important parameters of ‎hydraulic jumps in stilling basin were computed and compared for different Froude number. The results show that the permeable ‎baffle blocks and permeable end sill by changing the flow pattern in the stilling basin reduces the relative depth and relative length of ‎the hydraulic jump, while increasing the relative energy losses. The results also show which increasing the permeability of ‎baffle ‎blocks and end sill increases the relative energy losses and decreases relative depth and relative length of hydraulic jumps.‎

Osteoarthritis is a physiological response to the longitudinal and repeated forces applied to the joint which is associated with an increase in energy consumption and changes in the rate of displacement of the center of pressure in these patients. The purpose of the present study was to investigate the effect of 8 degree lateral wedge in medial compartment knee osteoarthritis energy consumption and displacement of the center of pressure in frontal plane.
The research design was quasi-experimental with a pretest - posttest. In this study, 26 patients with medial compartment knee osteoarthritis in the age (range of 40 to 60 years) were selected through available sampling. In order to measure the energy consumption the polar electro and measure displacement of the center of pressure the force plate apparatus were used. Participants were evaluated in two conditions with/without of using lateral wedge during walking.
The results showed that the mean of energy consumption and the displacement of the center of pressure decreased after using the lateral wedge. The average range of energy consumption before and after using the lateral wedge was respectively 0/381, 0/318 (p Use therapeutic interventions such as 8 degree lateral wedge may reduce energy consumption and displacement of the center of pressure of patients with medial compartment knee osteoarthritis.

Appropriate office workstation design and adjusted keyboard slope could prevent upper extremity musculoskeletal disorders caused by CTDs. The purpose of this study was to compare wrist and finger motion angles during typing in different workstations with different keyboard slopes.
In this experimental study, 10 female typists of university workers were chosen randomly. Test was performed on two different adjustable and non-adjustable chairs with four different keyboard slopes including 15, 7, 0, -7 degrees. Wrist and fingers kinematic data were calculated by Vicon motion analysis system and MATLAB software.
Average wrist flexion angles were significantly different in different keyboard slopes. In adjustable workstation, the lowest mean value of maximum, average, min mum of flexion was measured for keyboard whose slope was adjusted to 15 degrees. The lowest mean for observed flexion in the metacarpophalangeal joints in the second and fifth fingers was measured in workstation with adjustable seats and keyboard whose slope was adjusted to 15 degrees. In the proximal interphalangeal joint of the second finger, the lowest mean was obtained in the workplace with adjustable seats and the keyboard whose slope was adjusted to 15 degrees.
During typing on keyboard, as much as the finger joint angles are close to zero degree, less stress is put on the joints. In this study, the lowest means for the degrees of joint flexion were observed in the workstations with adjustable seats and the keyboard with 15-degree slope.

lower limb amputees may fail to accept and use their prosthesis because of discomfort experienced as a result of poor socket fit. Socket fir could have a great effect on amputee's gait and function. The aim of this study was to investigate the effect of ‘good‘ or ‘bad‘ socket fit on gait parameters, performance and satisfaction in below knee amputees. six below knee amputees experiencing a ‘bad’ socket fit due to residual limb volume lost participated in the study. Each amputee was then provided with a new good fitting PTB socket. temporospatial and kinematic parameters of gait were recorded for each socket fit condition using Vicon motion analysis system. Besides, amputee’s performance, comfort and satisfaction were measured TAPES and SCS questionnaires. There was no significant difference the good or bad socket fit conditions in any gait parameters except for the symmetry index of maximum knee joint flexion angle in the stance phase. Where the difference between prosthetic limb and sound limb for the value of this parameter was decreased in the ‘good’ socket fit condition. Furthermore, results of TABES questionnaire indicate that amputee's functional limitation decreased and their satisfaction of artificial limb increased after using the new good fitting socket. It is suggested that a longer acclimation period is adopted to examine the effect of socket fitting on amputees gait and function.

in normal walking، repetitive vertical ground reaction forces are tansformed on musculo-skeletal system. Magnitude of force during impact is major contributor to overuse injuries. Purpose of this study was the evaluate to effect of standard and beveled heel at orthopedic shoe on vertical ground reaction forces during walking in healthy subjects. 30 healthy adults (12 male، 18 female) participated in this study by simple impossible sampling. Subjects walked along an 8-m walkway in three different conditions: barefoot، orthopedic shoe with standard heel and orthopedic shoe with beveled heel. Vertical ground reaction force data collected in initial stance phases of walking using Kistler force plate. Results of this study showed significant increasing in impact force in barefoot compared with orthopedic shoe with standard and beveled heels (p˂0. 0001). First peak of vertical force and loading rate showed significant reduction in orthopedic shoe with beveled heel compared with orthopedic shoe with standard heel (p˂0. 05). using the beveled heel by changing the location of the ground reaction force from the ankle joint axis، facilitated first rocker and reduce first peak of vertical force and loading rate. because of complication of deleterious loads on lower limb during walking، we could use of this type of heel for some of the patient with special orthopedic disease.

in normal walking, repetitive vertical ground reaction forces are tansformed on musculo-skeletal system. Magnitude of force during impact is major contributor to overuse injuries. Purpose of thisstudy was the evaluate to effect of standard and positive posterior heel flare at orthopedic shoe on vertical ground reaction forces during walking in healthy subjects. 30 healthy adults (12 male, 18 female) participated in this study. Subjects walked along an8-mwalkway in two different conditions: orthopedic shoe with standard heel and orthopedic shoe with positive posterior heel flare. Vertical ground reaction force data collected in initial stance phases of walking using Kistler force plate. results of this study showed significant reduction in impact force in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel (p˂0.0001). No differences between conditions were observed in impact force time and first peak of vertical force. time of First peak of vertical force showed significant increasing in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel(p˂0.05). loading rate showed significant reduction in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel(p˂0.05). using positive posterior heel flare reduce the impact force and loading rate that could be due to its flexibility and impact absorption of this heel during walking. because of complication of these loads on lower limb specially in early phase of walking we could use of this type of flare for some of the patient with special orthopedic disease.