Based on the physical modeling of the improved muffler in this paper, Methods for internal acoustic computation of the muffler with SYSNOISE software based on Indirect Boundary Element Method are introduced and the ra...
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The engineering Technology National Forum (ETNF) was launched in 2008 by three engineering technology colleagues at Purdue University as an action team to address significant issues of the day affecting the ET educati...
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In this paper, the overall designing idea on real terrain is firstly proposed, the geometric modeling process is introduced, BinSplit binary segmentation algorithm is put forward based on fractal theory and midpoint d...
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In this paper, inner flow field model of underwater weapon is constructed;numerical calculation of the field is performed with Fluent software by the way of dynamic mesh method, thus simulation of inner ballistic of u...
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According to the analysis and the research on the residential environment concept and methods of the planning and design of the modern residential environment, it discusses residential environment planning and design ...
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With the recent rapid growth of urban development, particularly in medium-sized cities in Mainland China, there is a need to investigate the relationships between urban form and travel behavior by different-purposed t...
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The electrode displacement signal of resistance spot welding process is monitored and mapped into a 15×25 element bipolarized matrix by means of some method of fuzzy theory. The electrode displacement pattern mat...
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MMP16 stands for 16-bit Didactic Micro-Programmed Micro-Processor and consists in a comprehensive learning tool for those students of electric engineering and related disciplines that, having studied the basics of dig...
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A three-dimensional finite element model is established to analyze the cutoff behavior of retaining structures on groundwater seepage and settlement induced by dewatering. The cutoff behavior is influenced by many fac...
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A three-dimensional finite element model is established to analyze the cutoff behavior of retaining structures on groundwater seepage and settlement induced by dewatering. The cutoff behavior is influenced by many factors, such as penetration depths of retaining structures, and hydraulic characteristics of aquifers. Results show that both drawdown of groundwater level and settlement outside of the excavated pit decrease with the increase of the relative insertion depth of retaining structures in Aquifer I (AqI). Variations of groundwater level (Dh) and settlement (s) increase with the increase of hydraulic conductivities of AqI, whereas Dh decreases with the increase of specific storage of Aquitard I (AdI). In case of AqI with low permeability, it is acceptable that retaining structures has a relative insertion depth larger than 70%. However, retaining structures should penetrate into AdI when AqI has a permeability greater than 1 m/d.
Groundwater is pumped from both phreatic aquifer and confined aquifer to keep dry working space and ensure construction safety in deep excavations. During excavation, retaining structures are used not only to retain t...
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Groundwater is pumped from both phreatic aquifer and confined aquifer to keep dry working space and ensure construction safety in deep excavations. During excavation, retaining structures are used not only to retain the soft soil but also to cut off groundwater seepage from the surroundings. The cutoff effect on groundwater seepage is influenced by many factors, such as hydraulic parameters of the aquifers, the insertion depth and width of retaining structures, etc. To elucidate the cutoff behavior of retaining structures, experimental investigation was conducted in a rectangular sand tank in laboratory. Groundwater level was all the same in the initial stage. During the seepage tests, water head was set as a constant at the upstream boundary with a free seepage boundary at the downstream. In the different cases, the insertion depth (D) of cutoff wall was changed. For each case, water level and flow rate were measured. Based on experimental results, this research reveals how the insertion depth and width of retaining structure influence groundwater seepage in and around the retaining structure in an unconfined aquifer. It shows that drawdown of groundwater head decreases, and overall flow rate increases with the decrease of the insertion depth of cutoff wall. The differential value of groundwater level between upstream and downstream sides increases dramatically when D/H (H=thickness of sand layer) is over 70% for the sand soil used in the test.
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