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991.
992.
油库储存了大量易燃易爆品,设备操作过程较为复杂,易发生事故,所以员工须经过培训后才能上岗。传统培训系统偏重理论层面,培训效果差。以Unity3D作为开发平台,研发出一套交互式虚拟油库培训系统。系统采用C#作为交互脚本的开发语言,SQL Server进行数据管理,以第一人称视角漫游的形式实现设备属性查询、设备交互操作、重要工艺流程仿真等功能。系统具备非常真实的三维效果及交互功能,加强了对油库工作人员的培训效果。  相似文献   
993.
Morphology of antennal sensilla and their distribution were investigated in adults of Ooencyrtus nezarae, an egg parasitoid of Riptortus pedestris, using scanning electron microscopy. Male antennae was found to be significantly greater in overall length than female antennae. The antenna of O. nezarae was composed of the radicula, scape, pedicel, funicle and clava in both sexes, with seven types of sensilla identified: sensillum trichodea; s. finger‐like; s. placoidea; s. chaetica; s. basiconica; s. coeloconica, and s. campaniform. They occur in varying number and distribution along the antennae. Two sensillum types were further categorized into additional subtypes, with two subtypes in s. trichodea and three in s. chaetica. Among all characterized sensilla, s. trichodea subtype 1 and s. placoidea were multiporous, indicating that the primary function of these sensilla is olfactory. Sensillum trichodea was the most abundant sensillum type on the antennae of both sexes. Sexual dimorphism was only observed from the subtype 1 sensilla of s. trichodea in males and the subtype 3 sensilla of s. chaetica in females. The morphological information established in our study may provide useful information for further investigations in sensory physiological function of each morphological type of sensilla and their related behavior in this egg parasitoid.  相似文献   
994.
Journal of Mechanical Science and Technology - The sketch is one of the most important tools for industrial designers to solve problems and is actively utilized early in the process of developing...  相似文献   
995.
Journal of Mechanical Science and Technology - Lithium bromide (LiBr)-H2O triple-effect absorption chillers are supposed to have a much higher carbon steel corrosion rate under high temperature...  相似文献   
996.

Electronic devices must be quiet during manipulation for operations. In addition, the sounds need to show distinct impression to satisfy the user’s auditory experience and indicate the completion of an operation. The sounds occur in a short time from frictional contact and the consequent structural vibration when a user operates a device. In this study, the impact sound during printer cassette insertion is analyzed. The rail vibration during closure movement generates continuous sound. This movement ends with the impact sound from contact between the cassette and printer body. The sounds occur as clicking sounds with double impacts separated by a short interval. This clicking sound is important serving as an indicator of completed insertion. The user’s perception of this complex sound is investigated. A physical index to quantify the generated sound is proposed to assist comparisons between printers. Prony’s method was used to characterize the sound features including duration, double impact interval, magnitudes, and decay rates. From the extracted features, artificial clicking sounds were simulated for sound quality evaluations. Auditory experiments were performed to investigate the user’s preference for the separated rail and impact noises. The just noticeable difference was defined to classify the important factors influencing the perception characteristics.

  相似文献   
997.
Journal of Mechanical Science and Technology - Threaded fasteners are widely used in mechanical structures primarily owing to their easy disassembly for maintenance and low cost. However, the...  相似文献   
998.
Journal of Mechanical Science and Technology - Sodium (Na) organic batteries have attracted great attention because of high abundance of Na, low-production cost, and structure diversity of organic...  相似文献   
999.
Journal of Mechanical Science and Technology - This study investigates the possibility of achieving 65 % efficiency in a gas turbine combined cycle. Several options to realize it were compared. A...  相似文献   
1000.
A numerical study of the combustion of lean methane/air mixtures in a porous media burner is performed using novelty geometry, cylindrical annular space. The combustion process takes place in the porous space located between two pipes, which are filled with alumina beads of 5.6 mm diameter forming a porosity of 0.4. The outer tube diameter of 3.82 cm is isolated; meanwhile the inner tube of 2 cm in diameter is covered by a continuous set of thermoelectric elements (TE) for transforming heat energy into electricity. To achieve and maintain the proper temperature gradient on TE, convective heat losses are considered from the TE. Computer simulations focus on the two-dimensional (2D) temperature analysis and displacement dynamics of the combustion front inside the reactor, depending on the values of the filtration velocity (0.1 to 1.0 m/s), the heat loss coefficient from the internal cylinder (400–1500 W/m2/K), and the fuel equivalence ratio (0.06– 0.5). The conditions that maximized the overall performance of the process of energy conversion are: 0.7 m/s of the filtration velocity, 0.363 of the fuel equivalence ratio and 1500 W/(mK) of the heat transfer coefficient from the internal cylinder, to obtain 2.05 V electrical potential, 21 W of electrical power, and 5.64% of the overall process efficiency. The study shows that the cylindrical annular geometry can be used for converting the energy of combustion from lean gas mixtures into electricity, with a performance similar to the specified by manufacturers of thermoelectric elements (TE).  相似文献   
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