Carriage-rail assembly for high-resolution mechanical positioning

Carriage-rail assembly effects extreme resolution and position accuracy with little friction, and is applicable to such apparatus as optical benches, inspection fixtures, machine tools, and photographic equipment. Directions for assembly construction are given

Construction of an optical test-bed for eLISA

In the planned eLISA mission a key part of the system is the optical bench that holds the interferometers for reading out the inter-spacecraft distance and the test mass position. We report on ongoing technology development for the eLISA optical system like the back-link between the optical benches and the science interferometer where the local beam is interfered with the received beam from the distant spacecraft. The focus will be on a setup to investigate the tilt-to-pathlength coupling in the science interferometer. To test the science interferometer in the lab a second bench providing a laser beam and a reference interferometer is needed. We present a setup with two ultra-stable low expansion glass benches and bonded optics. To suppress the tilt-to-pathlength coupling to the required level (few μm/rad) imaging optics are placed in front of the interferometer photo diodes

High-Performance Architecture for Binary-Tree-Based Finite State Machines

A binary-tree-based finite state machine (BT-FSM) is a state machine with a 1-bit input signal whose state transition graph is a binary tree. BT-FSMs are useful in those application areas where searching in a binary tree is required, such as computer networks, compression, automatic control, or cryptography. This paper presents a new architecture for implementing BT-FSMs which is based on the model finite virtual state machine (FVSM). The proposed architecture has been compared with the general FVSM and conventional approaches by using both synthetic test benches and very large BT-FSMs obtained from a real application. In synthetic test benches, the average speed improvement of the proposed architecture respect to the best results of the other approaches achieves 41% (there are some cases in which the speed is more than double). In the case of the real application, the average speed improvement achieves 155%

Very Good Benches

As cities strive to become more sustainable and highly optimized, they have begun to embrace the current trend of “smartness” in ubiquitous computing. This is seen in the implementation of “smart” infrastructure throughout neighborhoods. Objects which typically do not sense or respond to users, like benches, can now offer Wi-Fi, charging outlets and weather reports. “Very Good Benches” explores alternative networking strategies and interactions, using Research through Design, Speculative Design, and Prototyping methodologies, to create a series of smart benches that re-imagine smart infrastructure through the lens of social interaction and the optimization of public engagement. The goal of each bench is to become a “very good bench” by attracting as many user interactions as possible from the public in order to develop an internal dataset that determines how and when the bench attracts users. Each bench senses occupancy and vacancy through the use of e-textile sensors and attracts interactions through audio and visual outputs by combining solenoids and LED lights. Wheels are incorporated in the design so users are able to arrange the set of benches in ways that best suit them. Through these interactions, a dataset is developed and used to create a ranking system amongst the networked benches which drives each one to compete to be the bench with the most frequent interactions. By putting more emphasis on the benches and occupants themselves and less attention on larger ideas of optimization, more playful interactions are able to be developed through the object’s perceived personalities. These benches are then able to imagine new possibilities for smart technologies in the public realm as a result of reinterpreting the optimization and efficiency of urban infrastructure through this specific case study

Об уменьшении динамического действия испытуемого объекта на виброиспытательный стенд

The mathematical substantiation of decreasing the influence of vibrations of a tested object on electrodynamic and electromagnetic benches is given. The structural schemes of benches with compensating feedbacks are shown

Readout system test benches

We propose to develop and exploit versatile multi-purpose Personal Computer-based Test Benches to support the evaluation and design of the basic elements required for digital front-end readout and data transmission systems for an LHC experiment. These test benches will have modular hardware facilities for the operation of new readout system components under realistic conditions, and will implement advanced modern software engineering concepts. They will support components such as fast ADCs, hybrid fibre-optic transceivers, and the prototype VLSI systolic array and data-flow processors currently being developed in national research laboratories and by the emerging European HDTV industry. These efforts would also lay the foundations for projects involving the development of custom-designed VLSI circuits

When Gravity Fails: Local Search Topology

Local search algorithms for combinatorial search problems frequently encounter a sequence of states in which it is impossible to improve the value of the objective function; moves through these regions, called plateau moves, dominate the time spent in local search. We analyze and characterize plateaus for three different classes of randomly generated Boolean Satisfiability problems. We identify several interesting features of plateaus that impact the performance of local search algorithms. We show that local minima tend to be small but occasionally may be very large. We also show that local minima can be escaped without unsatisfying a large number of clauses, but that systematically searching for an escape route may be computationally expensive if the local minimum is large. We show that plateaus with exits, called benches, tend to be much larger than minima, and that some benches have very few exit states which local search can use to escape. We show that the solutions (i.e., global minima) of randomly generated problem instances form clusters, which behave similarly to local minima. We revisit several enhancements of local search algorithms and explain their performance in light of our results. Finally we discuss strategies for creating the next generation of local search algorithms.Comment: See http://www.jair.org/ for any accompanying file