Advanced Materials Research Vol. 705

Abstract: According to the basic principles of green redesign, CKA6150 CNC lathe is comprehensively analyzed and evaluated by the green degree evaluation model. The results show that the green redesign of the CKA6150 CNC lathe meets all the requirements of the green products. It not only meets the technical requirements of the product's features, performance and life and cost, but also reduces the effect on environment in the process of production, using and recycling.

Abstract: Based on the finite deformation theory nonlinear differential equations of uniform-sectional circular arch is deduced, and analytical solution for displacement of the non-hinged arch under load is obtained. This paper provides a theoretical basis for the analysis and calculation of the long span arch.

Abstract: A numerical insight was accomplished to optimize the scramjet combustor configuration based on orthogonal experimental design. Parametric modeling of combustor configurations was performed by the orthogonal array with 13 factors at 3 levels. Numerical simulations were proceeded by k-ε standard turbulence model and eddy-dissipation model in the combustion process. The performance indexes of combustion efficiency, total pressure recovery coefficient and thrust gain coefficient were evaluated. Detailed comparison with the effect of the factors on the performance was also carried out to demonstrate the main factors and determine the optimal configuration. The analysis of the extreme differences of the factors indicates that the main factors affecting combustion efficiency were the length of the wedge, the length depth ratio of the cavity, the depth of the cavity, and the length of the expanding section; The main factors affecting total pressure recovery coefficient are the angle of the primary combustor, the length of the expanding section, and the thickness of the strut; The main factors affecting thrust gain coefficient are the thickness of the strut, the length of the expanding section, and the angle of the secondary combustor. Validation of the optimal configuration is then confirmed that its performance is higher than the rest of the configurations, with the combustion efficiency of 0.915 and the total pressure recovery coefficient of 0.486, which are 31.5% and 65.9% higher than the experimental results, respectively.

Abstract: Over 30 years of cut-to-length harvesting machines experience have demonstrated their effectiveness to logging companies in the countries of the boreal forest zone; i.e. better labour conditions in terms of ergonomics and safety, and less environmental damage and reliability in combination with convenient operation and maintenance. The introduction of fully mechanized cut-to-length technology in Russia shows a number of challenges that reduces cut-to-length effectiveness. These include a lower productivity of harvester-forwarder chains and higher roundwood losses in comparison with the Nordic countries due to a number of objective and subjective reasons (service, training, forest management, motivation, etc). Wood harvesting machinery has developted in the Nordic countries in recent years. The major changes were in integrating the harvesting of logging residues and stumps into the traditional system. Future prospects of cut-to-length technology require the development of forest logistics and forest bioenergy, and better environmental compatibility of wheeled vehicles with forest loam and clay soils.

Abstract: The inverse heat conduction problems (IHCP) analysis method provides a promising approach for acquiring the thermal physical properties of materials, the boundary conditions and the initial conditions from the known temperature measurement data, where the efficiency of the inversion algorithms plays a crucial role in real applications. In this paper, an inversion model that simultaneously utilizes the process evolution information of the objects to be estimated and the measurement information is proposed. The original IHCP is formulated into a state-space problem, and the unscented Kalman filter (UKF) method is developed for solving the proposed inversion model. The implementation of the proposed method does not require the gradient vector, the Jacobian matrix or the Hessian matrix, and thus the computational complexity is decreased. Numerical simulations are implemented to evaluate the feasibility of the proposed algorithm. For the cases simulated in this paper, satisfactory results are obtained, which indicates that the proposed algorithm is successful in solving the IHCP.

Abstract: For the general broaching machines problems of structure bulkiness, poor cylinder synchronization, lack of optimization design, low-grade control system, low efficiency and operational reliability, the paper studied the structural optimization technology of the large-scale high-performance CNC vertical broaching machine, designed the new 360-degree high-load lateral rotary table, the axial-rotary multi-pass joint of the anti-leakage and the elastic-contact, and the modular slider rails, so as to improve the mechanical performance, the working stability and reliability. The remote network intelligent monitoring system and the multi-function data acquisition processor for the developed CNC broaching machine, realize the enterprise management information, the enterprise resource optimization, and the automation and intelligence of the manufacturing process.

Abstract: The cost of picking the agriculture product is probably the major factor in determining whether or not there will be an economically successful season for most farmers. Hand harvesting has been costly, whereby, the cost of production constitute up to 80% of the total cost. Jatropha curcas has been considered as a potential feedstock for biodiesel production. Today, Jatropha curcas have been widely planted for harvesting its fruits for biodiesel production. Unfortunately, until now, the cost of jatropha production for biodiesel production is still high, especially labor costs for harvesting. The aim of the present study was to design, construct and evaluate a portable jatropha harvester to reduce dependence on human labor in the harvesting process. This smart harvester was developed by devising a simple crank powered by a hand drill 12 volt (V) that converts the rotary motion to linear motion at a push rod. To evaluate the machine performance, a factorial experiment with randomized complete randomized design (RCBD) in ten replications was conducted, the factors being shaking frequency (180, 250 and 300 rpm) and shaking duration (5, 10 and 15 seconds). To calculate the ratio of fruit detachment force (F) to its weight (W), appropriate measurements were made. Also, the geometric mean diameter of the fruits was determined at different stages of maturity. Analysis of variance (ANOVA) and comparison of means by Duncan's multiple range test (DMRT) showed that the effects of shaking frequency and shaking time on fruit detachment were greatly significant. The number of fruits detached increased by increasing the shaking frequency. Maximum number of fruits detachment was obtained by applying 300 rpm shaking frequency. Also the number of fruits detached increased by increasing the shaking duration.

Abstract: Engineering technological especially on automation and mechanization in agricultural and plantation industry is still new and still under research and development. The application of computer, mechatronics and machines for agricultural production has been one of the outstanding developments in Malaysian agriculture. This paper describes on the recent research at Malaysian public university on the uses of computer and electronics towards machines for the agricultural operations. It has been generally agreed that industrial robotics do not provide sufficient information related to the bioproduction field, although some fundamental theories and technologies were applicable to the bioproduction machine. Agricultural products are diversified and complicated, the environment around the objects changes from time to time, and the machine mechanism should adapt to physical properties and cultivation methods of the biological objects. These are some of the considerations that agricultural mechanization needs to address. Current trend in agriculture is integration with biotechnology application, the demand of which may increase in conjunction with the land capabilities by variety humanity activities. Although adoption of one agriculture activity per house area is a viable strategy in the framework of food security, as in a general, an agricultural production is labour intensive. The agricultural landscape has seen an increase in adoption of modern technologies, be it in small scales, including those in the agro-based manufacturing sector. This, to some extent, has increased the productivity and at the same time decreased the labour dependency. In conclusion, studies on electronic and computer-assisted devices leading to automation for application in agriculture had to be perpetually carried out.

Abstract: Malthusian population growth model is not applicable to the real world situation in most cases, since the simplifying assumptions are too ideal. In this article, we will generalize the classic population growth models by Stochastic differential equations, and get the extended models appealed to the real world better as well. When modeling the environmental perturbation by white noise process, we get an advanced model .

Abstract: In order to eject water column with regular shape for hydraulic impact tests, inertia projecting devices are developed. In these devices, a projecting cylinder filled with water is accelerated under huge push of gas gun. When arriving to set speed, the cylinder would impact buffer and suddenlly halt. Then water column in the cylinder will eject under inertial function. In the device for ejecting smaller water column, as impact force is small, projecting cylinder is made of high strength steel material, and can be used again after impacting buffer made of rubber material. In the device for ejecting larger water column, as impact force is huge, projecting cylinder is made of low strength steel material, and will damage after impacting buffer made of high strength material. Using these devices, tests are respectively conducted to eject water column with masses of 30kg and 800kg, and speed and shape of water column all satisfyed requirement of .hydraulic impact tests.