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日本森精机制作所推出新品——高精度立式加工中心NV7000,以满足汽车、航空、模具和工业机械等领域的加工需求。  相似文献   
57.
The authors present a new inverse, interactive approach to acoustic design that applies optimization techniques to an acoustic simulation system. For a new building, the system may suggest optimal configurations that would not otherwise be considered; for a hall with modifiable components or for a renovation project, it may assist in optimizing an existing configuration. Our system allows the designer to constrain changes to the environment and specify acoustic performance goals as a function of time. The constraints include the specification of a range of allowable materials as well as geometric modifications for surfaces in the hall. The designer also specifies goals for acoustic performance in space and time via high-level acoustic qualities such as decay time and sound level. Using this information, the system performs a constrained optimization of surface material and geometric parameters for a subset of elements in the environment. The system operates at varying accuracy levels, offering trade-offs between time and quality. Visualization tools facilitate an intuitive assessment of the complex time-dependent nature of sound, and they provide a means to express desired performance. By using optimization routines within an interactive application, our system reveals complex acoustic properties and steers the design process toward the designer's goals  相似文献   
58.
In early or preparatory design stages, an architect or designer sketches out rough ideas, not only about the object or structure being considered, but its relation to its spatial context. This is an iterative process, where the sketches are not only the primary means for testing and refining ideas, but also for communicating among a design team and to clients. Hence, sketching is the preferred media for artists and designers during the early stages of design, albeit with a major drawback: sketches are 2D and effects such as view perturbations or object movement are not supported, thereby inhibiting the design process. We present an interactive system that allows for the creation of a 3D abstraction of a designed space, built primarily by sketching in 2D within the context of an anchoring design or photograph. The system is progressive in the sense that the interpretations are refined as the user continues sketching. As a key technical enabler, we reformulate the sketch interpretation process as a selection optimization from a set of context‐generated canvas planes in order to retrieve a regular arrangement of planes. We demonstrate our system (available at http:/geometry.cs.ucl.ac.uk/projects/2016/smartcanvas/ ) with a wide range of sketches and design studies.  相似文献   
59.
Mean-field statistical thermodynamics theory has recently been developed to account for the partitioning of solutes from aqueous mobile phases into reversed-phase liquid chromatography stationary phases. Several predictions are tested here against an extensive data base of nearly 350 sets of experiments. In agreement with theory, we find that (i) the dependence of retention on mobile phase composition can often be suitably linearized through use of a type of composition plot recently suggested by Dill, (ii) retention measurements can be used to determine the binary interaction constants of solutes with solvents, and (iii) ET-30 solvent probe experiments appear to provide a direct measure of the binary interaction constants. This work suggests that the simple random-mixing approximation for solutes with solvents is often useful even for complex chromatographic solutions.  相似文献   
60.
On the learning control of a robot manipulator   总被引:1,自引:0,他引:1  
This paper derives a learning control law to achieve trajectory following for a robot manipulator. The controller consists of two parts, a computed torque servo for the rigid body terms that can be modelled and a learning law for the unmodelled dynamics. An advantage of this method is that bounds can be assigned to the position and velocity tracking errors.  相似文献   
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