Local scour downstream of the hydraulic structures is of great importance. In wide channels, a set of multi gates instead of a single gate may be responsible for transferring water and adjusting upstream water level due to difficulty in gate maneuvering, economic considerations, and ease of movement. Operating parallel sluice gates can create different scenarios owing to clogging or failure in some gates. This study was aimed to assess the effect of different cases of parallel sluice gates operational management, gate opening to channel width ratio, and length of the separator walls on local scour development downstream of parallel sluice gates in different operations. Five operational scenarios were investigated on three parallel sluice gates. The results of the present study showed that the dimensions of the scour hole are a function of the symmetrical and asymmetrical operation of the gates. By reducing the gate opening to channel width ratio, the dimensions of the scour hole increased compared to the classical hydraulic jump mode. Maximum scour depth in the symmetric operational management scenario (B) and the asymmetric scenario (A), increased by 120% and 43%, respectively, compared to the ABC scenario. Increasing the length of the separating walls can be a suitable option to control the dimensions of the scour hole in different operations. Owing to a 20% increase in the length of the separator walls, the maximum scour depth decreased by 68% in the maximum Froude number (8. 6) and 122% in the minimum Froude number (4. 5) in scenario B. These percentages for scenario A are equal to 17 and 58, respectively. In addition, relations were presented to estimate the dimensions of scour hole in the symmetrical and asymmetrical operation of the parallel gates.

Introduction: In practical applications, at the downstream of hydraulic structures, in some cases, the width of the basin may be larger than the upstream supercritical flow (sudden expansion in the flow section). In such cases, an expanding hydraulic jump with symmetrical or asymmetrical shape will be developed at the downstream. Under the design of three parallel gates, the operation of the side or middle gate can be lead to the asymmetrical or symmetrical hydraulic jump, respectively. According to the position of the jump toe, expanding hydraulic jump can be classified into four types. The present study focuses on a T-shaped hydraulic jump, which the toe is established at the beginning of the divergence section. Most of the previous studies are related to the symmetrical expanding hydraulic jump. In this case, the downstream diverging channel is symmetric on the central axis of the channel. However, a systematic study on the effects of symmetry and asymmetry of the expanding hydraulic jump was not found in the literature. In this study, using the momentum principle, some theoretical equations to determine the ratio of the sequent depths of symmetrical and asymmetrical expanding hydraulic jump were derived. Also, some regression relations were proposed to estimate the length of expanding hydraulic jump. The new proposed equations were also extended for the presence of a sill. The equations were calibrated using available experimental data obtained in this and previous studies. This research also considered the characteristics of expanding hydraulic jump under the symmetrical and asymmetrical operation of the parallel gates. Methodology: To calibrate new proposed relations and investigate the effects of different parameters on the expanding hydraulic jump characteristics, two experimental data sets were used. In addition to the data set from Bremen (1990), the experimental data from the present study were used. The data were collected from a hydraulic model of three parallel radial gates for operating the side or middle gate, which corresponds with the asymmetrical or symmetrical expanding hydraulic jump, respectively. The experiments provided a wide range of different parameters as the approaching Froude number, hydraulic jump length, sequent depths ratio, divergence ratio, sill height, and relative length of gate separator wall. Results and discussion: Equation (4) was developed to determine the ratio of the sequent depths of expanding hydraulic jump based on the momentum equation. For the presence of a sill, a combination of Equations (4), (7) and (8) can be used to calculate the ratio of the sequent depths under the asymmetric and symmetric developments, respectively. Determining the ratio of the sequent depths requires the calculation of the adjacent water depths of the closed gates. For this purpose, in addition to regression equation development (i. e. Equation 13), Equation (12) was proposed. This equation is based on the calculation of the hydraulic jump profile. It was observed that under the calibration range, the regression equation is more accurate. However, Equation (12) is recommended for the range outside of the experimental observations. The results showed that: ❖ As the divergence ratio increases, the ratio of sequent depths approaches to the classic hydraulic jump. ❖ By decreasing the relative length of the gate separator wall and decreasing the width of the gate on the downstream channel width, the relative depth at the side gate and consequently the ratio of the sequent depths will decrease. ❖ For the lower length of the separator wall and under the operation of the middle gate, longer horizonta distance is needed to develop the jump than the side gate. However, as the length of the separator wall increases, the length and sequent depth of hydraulic jump due to the side gate increases on the middle gate. ❖ In the presence of a sill, the relative length of the hydraulic jump decreases, and the ratio of secondary depths increases. ❖ It was observed that the hydraulic jump due to the operation of the middle gate leans toward the left or right side of the channel due to oscillatory behavior. ❖ Under operating the middle gate and in the absence of a sill, an asymmetric hydraulic jump is formed in the channel face when the length of the separator wall is less than 38% of the classical hydraulic jump length. For the presence of a sill, the minimum length of the separator wall decreases to about 26%. ❖ By decreasing the initial depth of the hydraulic jump on the width of the gate and converting the output jet into a linear jet, the relative development length will be increased. ❖ As the sill height increases, the difference in the depths attached to the side gates will decrease, and the hydraulic jump will develop more symmetrically. ❖ As the relative height of the sill decreases, the minimum length of the separator wall increases and a symmetrical hydraulic jump in the flanks forms. Conclusion: This research developed a set of theoretical and regression relationships for estimating the length and sequent depth ratio of expanding hydraulic jump. Moreover, the effects of sill height, divergence ratio, and the length of the gate separator wall, were investigated. This study compares the effects of side and middle gate operations based on the variation of jump length and sequent depth ratio. The results can be used as a guide for the hydraulic structures operators to reduce the asymmetric severity of the expanding hydraulic jump and achieving the complete development under the minimum length.

In this research, the dynamics of local scour processes is studied in the context of the erosion that takes place downstream from a submerged sluice gate. The most important factors, which affect the local scour processes downstream of the sluice gate are identified and grouped by dimensional analysis to obtain the dimensionless parameters. Experiments were carried out in a horizontal rectangular flume of 9 m long, 0.5 m wide and 0.6 m height. Two gradations of uniform non-cohesive bed material were used for various tailwater depths and flow rate conditions. A total of 22 tests were carried out, each for a period of 12 h. An equilibrium scour condition was not attained over this time period for any of the tests, although a similarity in the bed profiles is observed in the region close to the rigid apron. Based on the experimental data, new dimensionless equations and graphs are presented to determine the shape and dimensions of characteristic lengths of scour hole such as maximum depth of hole and its position, brink scour depth, maximum extension of whole, dune height and its distance from the end of apron. Also, the results are compared with previous researches.

Background and aim: One of the current problems in endodontic treatment is the establishment of optimal anesthesia on mandible. In this clinical study, two approved mandibular block technique were compared in the establishment of pulpal anesthesia.Materials and Methods: Inferior dental anesthesia via conventional and Gow - Gates techniques were evaluated using onset of anesthesia, pain severity duriny injection, aspiration test, pulpal anesthesia (via ice test, cavity test and pain during entrance into pulp chamber) and pinprick test (inferior alveolar, lingual and long buccal nerves). 58 patients requiring root canal rteatment of mandibular molars were divided into two groups.They were given injections of 1.8 ml of %2 lidocaine with adrenaline (1: 80,000). Results were analyzed using Mamm -Whitney and t-student tests.Results: No significant differences were found between two techniques in ice test, cavity test, pain upon entrance to pulp chamber, pinprick test, aspiration test and injection better results about injection pain and aspiration test. Time required for lip and tongue anesthesia in conventional technique was less than Gow - Gates (P< 0.001) although buccal nerve was anesthetized more in Gow - Gates Technique (P=0.01). Although the aspiration test did not show a significant difference, but the lack of positive aspitation case in Gow - Gates technique, in conparison with %10.7 in conventional technique seemed to be important. No significant difference in pulpal anesthesia between two techniques was shown, however, %57.1 of patients had pain during entrance to pulp chamber in conventional technique comparing to %39.2 in Gow - Gates technique. The buccal nerve was anesthetized more in Gow – Gates technique (%75) as compared with conventional one (%42.9), which was significantly different (p=0.01), but other branches (inferior alveolar and lingual nerves) were anesthetized equally in both applied techniques. On average, patients acquired lip and tongue numbness in 1.42 and 3.27 minutes, respectively in conventional method but more than 7 minutes was required in Gow-Gates technique (p<0.001). Conclusion: Irrespective of the operator clinical experience, Gow-Gales technique appears to be more effective in pulpal anesthesia although more slowly yielded anesthesia, as compared with conventional method, is one of its disadvantages.

Radial gates are used widely as a kind of control gates, worldwide. Although they are used widely, discharge estimation is not easy and few studies have been cited in the literature. In the present study, new relationships for estimation of discharge coefficients under free flow and submerged conditions are obtained. In these relationships, the discharge coefficient was related to the gate lip angle and the ratio of the water head to the gate opening height. By using these relationships, the accuracy of estimated discharge is increased. For this purpose, nonlinear multiple regression analysis and a set of laboratory data were used. Some statistical parameters such as maximum error, average error and standard error and three sets of field observed data were also used for evaluation of the relationships.One set of these data was collected in the present study and the others from previously published studies. The ranges of used observed discharge data were 0.030 to 0.320 and 0.010 to 0.180 m3s-1 in laboratory under free flow and submerge conditions, respectively. For the field observed data, these ranges were 0.11 to 239.6 and 0.05 to 209.02 under free flow and submerged conditions.Results showed that the relationships obtained could be appropriate for estimation of discharge coefficients in free flow and submerged radial gates. Relationships including gate lip angle, gate opening and upstream water depth are more reliable than the ones using only gate opening and upstream water depth. The average values of discharge estimation error could be about 2 and 1 percent under submerged and free flow conditions, respectively.

In this paper after studying and analyzing BiCMOS and CMOS logical gates, we have achieved some advanced BiCMOS circuits for the same logical gates. In all of our designs, we used threshold detectors and voltage to current converters. In this new method, some parts of the conventional BiCMOS current-mode circuits have been eliminated without any changes in the logical functionality of the circuits, and some optimum circuits based on this logic family have been introduced. In the proposed circuits, we have obtained considerable speed gain and a remarkable reduction in transistor count.      

In order to use gated pipes efficiently, it is required to know the hydraulic properties of the gated pipe and its gates. The hydraulic properties of gated pipe's gates were studied. The manufacturing quality and the discharge similarity of gates were evaluated by computing values of indices including Cv, qvar and Range. Results indicate that the manufacturing quality of gates is acceptable and their hydraulic performance's is similar.Therefore, an equation was developed to relate gate discharge to the hydraulic head behind the gate and the gate degree of opening. The gate discharge was computed under various conditions of pressure head and degree of opening with the equation derived and compared with measured values. The computed values of gate discharge were close enough to the actual values for practical purposes. A computer program was developed to simulate gate discharges along a gated pipe. The program calculates gate discharge and pressure behind the gates along a gated pipe line based on known values of pipe slope, length of pipe, gate degree or opening, gate spacing, pipe inlet pressure or discharge of last gate on the pipe line, distance from the pipe inlet to the first open gate, and numbers of open and closed gates at the beginning of the pipe.