Increasing Strength of Sub-grade Layer of Pavement using Geo-grid

This Paper describes the beneficial impact of reinforcing the sub-grade layer with a single layerof geo-grid at different positions and thereby determination of optimum position of reinforcement layer. The( best) optimum position was determined based on California Bearing Ratio (CBR value) and unconfined compression tests were conducted to decide the optimum position of geo-grid. The CBR value of a soil increases by 50-100% when it is reinforced with a single layer of geogrid. The amount of development (Improvement) depends upon the type of soil and position of geo-grid. CBR of sub-grade soil is 6.53% without reinforcement and when geo-grid was placed at 0.2H from the top, the CBR value increased to 19.66%. Soaked Condition CBR of sub-grade soil is 4.77% without reinforcement and when geo-grid was placed at 0.2H from the top, the CBR value increased to 4.46%. Keywords: Pavement, Geo-grid, Reinforced, Sub-grade, CBR, Filtration, Reinforcing

The Effect of Variation in Cone Position Heigth on Raw Water Turbidity Removal in Sedimentation Unit Continuous Discharge Flow (CDF) Method as a New Method

Unit sedimentasi metode continuous discharges flow (CDF) adalah metode baru dalam menyisihkan kekeruhan yang menggunakan prinsip tangki bocor secara kontinu dan terkendali. Perubahan ketinggian posisi cone dari dasar zona pengendapan ke bagian atas, dapat memperkecil jarak antara sumber aliran buang akibat bocor yang berasal dari cone sebagai sumber gaya baru yang bekerja terhadap flok, dan pada akhirnya meningkatkan efisiensi penyisihan kekeruhan. Penelitian ini bertujuan untuk menganalisis efisiensi penyisihan kekeruhan air baku pada 3 variasi ketinggian posisi cone di zona pengendapan. Penelitian menggunakan reaktor skala laboratorium kapasitas 240 L/jam yang terdiri dari unit koagulasi terjunan, flokulasi baffle channel dan sedimentasi metode CDF. Unit sedimentasi metode CDF yang digunakan adalah CDF 6% dengan variasi ketinggian posisi cone 0 m, 0,33 m dan 0,66 m dari dasar zona pengendapan. Air baku yang digunakan adalah Sungai Batang Kuranji Kota Padang dengan kekeruhan 25,876 – 26,012 NTU dan tawas sebagai koagulan dalam proses koagulasi. Hasil penelitian menunjukkan efisiensi penyisihan kekeruhan pada ketinggian posisi cone 0 m, 0,33 m dan 0,66 m secara berurutan adalah sebesar 82,88%, 83,86% dan 84,60%. Ketinggian posisi cone 0,66 m dari dasar zona pengendapan adalah posisi optimum dengan efisiensi penyisihan kekeruhan 1,72% lebih besar dari posisi cone di dasar zona pengendapan, yaitu 0 m. Analisis pengaruh ketinggian posisi cone terhadap penyisihan kekeruhan menggunakan korelasi Rank Spearman, menunjukkan pengaruh yang sangat kuat, semakin tinggi posisi cone semakin besar efisiensi penyisihan. Bilangan Reynolds (NRe)dan bilangan Froude (NFr) pada aliran buang ini secara berurutan adalah 23,83 dan 9,33x10-4. ABSTRACTThe continuous discharges flow (CDF) sedimentation unit is a new method for removing turbidity using the principle of a continuous and controlled leaking tank. Changes in the height of the cone position from the bottom of the settling zone to the top, can reduce the distance between the exhaust flow sources due to leakage from the cone as a new force source acting on the floc, and ultimately increase the efficiency of turbidity removal. This study aims to analyze the efficiency of raw water turbidity removal at 3 variations in the height of the cone position in the settling zone. The study used a laboratory-scale reactor with a capacity of 240 L/hour consisting of a plunge coagulation unit, baffle channel flocculation, and CDF sedimentation method. The sedimentation unit for the CDF method used is 6% CDF with variations in the height of the cone position 0 m, 0.33 m, and 0.66 m from the bottom of the settling zone. The raw water used is Sungai Batang Kuranji, Padang City with a turbidity of 25.875 – 26.012 NTU and alum as a coagulant in the coagulation process. The results showed that the efficiency of removal of turbidity at the height of the cone 0 m, 0.33 m, and 0.66 m respectively was 82.88%, 83.86%, and 84.60%. The height of the cone position 0.66 m from the bottom of the settling zone is the optimum position with a turbidity removal efficiency of 1.72% greater than the cone position at the bottom of the settling zone, which is 0 m. Analysis of the effect of the height of the cone position on the removal of turbidity using Spearman's Rank correlation showed a very strong influence, the higher the cone position the greater the removal efficiency. Reynolds number (NRe) and Froude number (NFr) in this exhaust stream are 23.83 and 9.33x10-4, respectively.

Theoretical and experimental research on a new rotating standing wave ultrasonic motor

In this paper, a new rotating standing wave ultrasonic motor with multiple driving teeth is proposed. Using the method of adding additional teeth, the correction of the B06 surface of the ultrasonic motor vibrator is expected, the design of the optimum position of the drive tooth is realized. At the same time, a method of reducing the stiffness of the rotor is proposed, and the flexibility is met, the integrated design of the rotor and the pressure device can be realized by removing the disc spring. The accuracy of the finite element analysis is verified by the vibration test of the prototype oscillator. The finite element analysis of the main structure parameters of the influence oscillator mode and natural frequency is carried out. It provides theoretical basis for the design and machining of vibration.

Optimal distributed generation placement using artificial intelligence for improving active radial distribution system

There are several profits of distributed generator (DG) units which are believed for improving the safety of the distribution power grids. However, these profits can be maximized by ensuring optimum sizing and positioning of DG units because an arbitrary location of DG units may adversely affect and jeopardize power grids which could contribute to maximising of power loss and degradation of the voltage profile. Therefore, several approaches were suggested to ensure optimum position and size of DGs. The primary aim of this article is for establishing technique for optimum scheduling and operating of DG to lessen power loss, revamp voltage profile and overall network reliability. Artificial intelligence method called particle swarm optimization (PSO) is utilized for finding the best site and size of DG to lessen power loss and boost the voltage profile. In this paper, IEEE 33 distribution system is utilized to display applicability of PSO. The results of the PSO are compared with the results gotten by other methods in the literature. Finally, the results show that the PSO is superior than the other methods.

Experimental Investigation into the Optimum Position of a Ring Reflector for an Axial Virtual Cathode Oscillator

A ring reflector was experimentally investigated using an axial virtual cathode oscillator (vircator). The ring reflector was installed behind the mesh anode of the axial vircator to enhance the microwave power output by forming a resonant cavity and increasing the electron beam to microwave energy conversion efficiency. The optimum position of the ring reflector is analyzed through simulations and experiments by varying the anode to reflector distance from 6 mm to 24 mm in 3 mm steps. PIC simulations show that the ring reflector enhances the microwave power of the axial vircator up to 220%. Experiments show that the microwave power from the axial vircator without the ring reflector is 11.22 MW. The maximum average peak microwave power of the axial vircator with the ring reflector is 25.82 MW when the anode to ring reflector distance is 18 mm. From the simulations and experiments, it can be seen that the ring reflector yields decaying enhancement that is inversely proportional to the anode to ring reflector distance and there is no noticeable microwave enhancement after 24 mm. The frequency range attained from the simulations and experiments is 5.8 to 6.7 GHz and 5.16 to 5.8 GHz, respectively. The difference between the simulation and experimental results is due to the error in the anode to cathode gap distance. Although the frequency is slightly changed, the ring reflector seems to have no influence on the frequency of the generated microwave.

Lift-to-Drag Ratio of the Application of Hydrofoil With Variation Mounted Position on High-Speed Patrol Vessel

The hydrofoil is one of the hydrodynamic support technologies for marine vehicles that provide a high performance and are feasible to operate. The mounting position of hydrofoils on the hull is one of the keys to improving the hydrodynamic performance, where the existing academic literature to find the optimum position of hydrodynamic is still deficient. The objective of this study is to compare the mounting locations of hydrofoil in the horizontal axis in a high-speed patrol vessel. The comparison result is based on the computational fluid dynamics where the basic model was validated using experimental data. Three mounting location cases of hydrofoils were performed i.e. middle section, stern section, and behind the stern. The result shows that the optimal hydrofoil mounting position is after the transom. In this position, the value of the lift-to-drag ratio is higher by an average of 10% - 29% compared to other positions depending on the speed of the ship.

Optimal Design and Numerical Analysis of Soil Slope Reinforcement by a New Developed Polymer Micro Anti-slide Pile

As a new material, polyurethane polymer has been widely used in engineering in recent years due to the excellent engineering mechanical properties. Based on the characteristics of this material, a multi pipe grouting micro anti-slide pile is proposed, which is formed by using polymer slurry as grouting material. Compared with traditional anti-slide pile, the polymer micro pile has the advantages of strong applicability, no water reaction, small disturbance, fast construction, economy and durability. As a flexible retaining structure, polymer micro-piles can strengthen the slope by cooperating with the forces. However, there is no report on the reinforcement of slope by polymer micro piles at present. In this paper, a three-dimensional multi row polymer micro piles model for slope reinforcement considering different embedded depth and pile location is established. Safety factor, thrust force of landslide behind pile, length of pile and mises stress are taken as four factors to evaluate reinforcement effect, the optimal reliability of polymer micro anti-slide pile for slope reinforcement is evaluated by giving different weight values to each factor through multi factor comprehensive evaluation method. The safety factor of slope (Fs), landslide thrust behind pile and mises stress of pile are analyzed under different embedded depth (le) and pile position (px). The results show that the best embedded depth is about1/8 − 1/12 of the horizontal length of the landslide behind the pile when multi row polymer micro piles are used to reinforce the slope; the optimum position of pile arrangement is 0.55–0.65 times the slope length from the top of the slope.

Towards Finding the Optimum Position in the Visual Field for a Head Worn Display Used for Task Guidance with Non-registered Graphics

Where should a HWD be placed in a user's visual field? We present two studies that compare comfort, preference, task efficiency and accuracy for various HWD positions. The first study offsets a 9.2° horizontal field-of-view (FOV) display temporally (toward the ear) from 0° to 30° in 10° steps. 30° proves too uncomfortable while 10° is the most preferred position for a simple button-pushing game, corroborating results from previous single-task reading experiments. The second experiment uses a Magic Leap One to compare 10° x 10° FOV interfaces centered at line-of-sight, temporally offset 15° (center-right), inferiorly offset 15° (bottom-center), and offset in both directions (bottom-right) for an order picking task. The bottom-right position proved worst in terms of accuracy and several subjective metrics when compared to the line-of-sight position.