Papers by Keyword: Potential Energy

Abstract: The problem of calculating a cyclically symmetric design for the nodal radial load action is being solved in the article. The analysis of the stress-strain state of a circular ring plate subjected to the action of a regular distributed load along the outer contour is made. A comparison of the operation of the framed structure and its continuous analogue is performed. The thickness of an isotropic ring plate, which is equivalent in the static ratio of a planar framed structure of a regular construction is determined.

Abstract: The purpose of this study is to identify the solid waste generation and compositions that are generated from UNIMAS West Campus area and also to calculate potential energy and profit that can be harvested from the solid waste. This study was conducted at UNIMAS west campus where the samples of solid waste were collected from different types of source of generation namely residential colleges, faculties, Centre Teaching Facilities (CTF) and cafeteria. The solid wastes collected are weighed, mixed, quartered and the compositions of the samples are determined. From the analysis, the solid waste generation rate is 499 kg per day and the major composition of solid waste produced from this study area is food waste with the value of 54% followed by plastic bottle with 9%, mixed plastic with 8%, mixed paper with 7%, box and polystyrene are with 5% and the less percentage of solid waste composition is aluminium with 4%. For the total estimation potential energy that generated by UNIMAS West Campus is about 12819.9 kJ/kg per day and the profit can be achieved when the solid wastes are recycles is about RM 126.43 per day. The analysis shows that solid waste generated in UNIMAS West Campus has a good potential in recycling and give more benefit to UNIMAS. With the data of the solid waste generated in this study area, proper management strategies can be planned by top management of UNIMAS and put it into action in the future. In long term, it will make UNIMAS a green campus which eventually reduces the amount of solid waste generation.

Abstract: In Pb-free Al-Sn welding of electrolytic parts, single-crystal Sn whiskers easily form and can cause problems such as short circuits. Here we report that the growth of Sn whiskers in the weld zone of Al electrolytic condenser leads was suppressed in a vacuum environment. We examined the effect of the environment and weld metal microstructure in order to understand how to control and prevent whisker growth. In vacuum, the weld zone did not form whiskers after more than 100 h, whereas in air, whiskers grew within several hours. This suggests that whiskers require oxygen to form. The growth can be explained by the energy balance between the potential energy of the weld metal and the surface energy of the whisker. Our results will contribute to developing techniques for suppressing the formation of Sn whiskers during the percussion welding of Al electrolytic capacitor leads.

Abstract: The article deals with the computational model of an elastic von Mises planar truss. The description of a mathematical concept, which is intended for the creation of computational programmes based on a finite number of segments, is presented. The mathematical solution is suitable for the analysis of load-deflection curves. Structural deformation is evaluated by seeking the minimal potential energy. The article examines the effects of change in the vertical displacement of the top joint on strut axes. The step by step incremental method is used in combination with the Newton-Raphson method. The presented study is aimed at the evaluation of the force in the bifurcation point, which determines the moment when loading of the model causes passing from the pre-critical effect (attainment of maximum vertical load action) to the post-critical effect. Symmetric and asymmetric initial axis imperfections are considered and relevant symmetric and asymmetric shapes of buckling are identified. The stability problem of the von Mises truss is discussed in connection with the random effects of imperfections.

Abstract: Studies on the potential of plastic solid waste (PSW) as a fuel supplement for power plant was conducted to determine the potential energy and economic value in Indonesia. In analyzing the potential energy and economic value of PSW, 15 cities provinces having municipal solid waste production of greater than 1,000 tons/day were selected. The study showed that with the total potential of PSW of around 693 tons/day, the electrical energy potential available is around 7,987 MWh/day. The PSW equivalent with coal is approximately 1,065 tons/day, and its equivalent to the oil is around 593 tons/day. In conclusion, the PSW is an environmental pollution material but have the energy and economic potential to be used as a fuel supplement for the power plants. Thereby, it can save the use of coal by means co-combustion with PSW and at the same time be able overcome the environmental problems caused by pollution PSW in Indonesia.

Abstract: The paper proposes a new method that utilizes Parallel Estimation of Distribution (PED) to obtain disparity map of two images and fuses 3D point-cloud by the disparity. Estimation of Distribution (ED) has several advantages such as low complexity and high efficiency while it also has the shortcoming that it’s sensitive to initial samples and the final solution is local optimum but global optimum. In order to exert its merit and overcome the shortcoming, this paper will improve the ED by parallel sampling to diminish the sensitivity with Adaptive Support-Weight method. We called it Parallel Estimation of Distribution (PED). After disparity map is obtained, the two images will be divided into high frequency and low frequency by lifting wavelet respectively and the frequency coefficient of each image will be averaged into fusion frequency. Finally, the fused frequency coefficient will be transformed by inverse lifting wavelet to the final fused image. The experiment has proved that the matching speed is outstanding without losing precision.

Abstract: Evaporative cooling is able to generate the cooling medium at a temperature approaching to the ambient wet bulb temperature. In this paper, a low-energy air-conditioning strategy is proposed, which is a combination of cooled ceiling (CC),microencapsulated phase change material (MPCM) slurry storage and evaporative cooling technologies. The assessment of evaporative cooling availability and utilization is done for five representative climatic cities, including Hong Kong, Shanghai, Beijing, Lanzhou and Urumqi in China, and the energy saving potential of the proposed air-conditioning system is analyzed by using a well validated building simulation code. The results indicate that the new system offers energy saving potential up to 80% under northwestern Chinese climate and up to 10% under southeastern Chinese climate. The optimal design method of the slurry storage tank is also proposed based on the slurry cooling storage behaviors and cooling demand variations of the ceiling panels.

Abstract: The paper presents the mathematical modeling of the wave energy capture process. The wave energy is transformed into torque by a device composed of multiple floating cylinders, which perform oscillating motions according to the wave parameters and to the constructive elements of a new patented device.

Abstract: The utilization of rice husk as an alternative fuel for the power plant in Indonesia is still under study. In present, steam power plants in Indonesia are still using coal fuel. This study was conducted to obtain data on the development potential of rice husk within 12 years duration. The potential of rice husk for each province was obtained by analyzing the rice production of 22 provinces that have rice production greater than 1 million tons per year. The study shows that the potential of rice husk and potential electrical energy increased by about 36.8% within 12 years or an average increase of around 3.1% per year. For the potential of rice husk in 22 provinces, the total gain was estimated 12.76 × 10⁶ tons which is equivalent to 6.62 × 10⁶ tons of coal or equivalent to 3.68 × 10⁶ tons of oil. The available capacity of power plants is around 5,664 MW with the potential of electric energy is around 49,622 GWh. This potential is equivalent to 50% of the energy needs of coal in Indonesia in 2011, which was about 99,312 GWh. In conclusion, rice husk is indeed potential to be used as an alternative fuel in power plants thanks to its increasing yearly production and ability for distribution to all provinces in Indonesia.

Abstract: Floating body with rope wheel structure is a new wave energy device, which is simple and low cost. Mooring system is the key technology of this device, which is use to limit the horizontal motion of the floating structure in the designated area. In this paper, potential energy theory has been used in the process of design and calculation of mooring system. Using the result of calculation, the motion of the floating body has been simulated numerically.