Improved N-Best Extraction with an Evaluation on Language Data

We show that a previously proposed algorithm for the N-best trees problem can be made more efficient by changing how it arranges and explores the search space. Given an integer N and a weighted tree automaton (wta) M over the tropical semiring, the algorithm computes N trees of minimal weight with respect to M. Compared to the original algorithm, the modifications increase the laziness of the evaluation strategy, which makes the new algorithm asymptotically more efficient than its predecessor. The algorithm is implemented in the software Betty, and compared to the state-of-the-art algorithm for extracting the N best runs, implemented in the software toolkit Tiburon. The data sets used in the experiments are wtas resulting from real-world natural language processing tasks, as well as artificially created wtas with varying degrees of nondeterminism. We find that Betty outperforms Tiburon on all tested data sets with respect to running time, while Tiburon seems to be the more memory-efficient choice.

Selection of the Optimal Structural Design of a Spar Composite Wing

This paper describes a method for optimizing the design of a spar-type composite aircraft wing structure based on multi-criterion approach. Two types of composite wing structures such as two-spar and three-spar ones were considered. The optimal design of a wing frame was determined by the Pareto method basing on three criteria: minimal weight, minimal wing deflection, maximal safety factor and minimal weight. Positions of wing frame parts, i.e. spars and ribs, were considered as optimization parameters. As a result, an optimal design of a composite spar-type wing was proposed. All the calculations necessary to select the optimal structural and design of the spar composite wing were performed using nonlinear static finite element analysis in the FEMAP with NX Nastran software package.

Evaluation of Discoloration and Subterranean Termite Resistance of Four Furfurylated Tropical Wood Species after One-Year Outdoor Exposure

The discoloration and resistance to subterranean termite attack of four furfurylated fast-growing tropical wood species were evaluated after outdoor exposure for 1 year in Bogor, Indonesia. For comparison purposes, imidacloprid-preserved and untreated wood samples were also prepared. Discoloration of all treated samples was measured before and after the furfurylation process. The wood specimens were then placed vertically to three-fourths of their length in the ground for 1 year, at which point they were evaluated for resistance to subterranean termite attack. After furfurylation, wood samples were darker in color than untreated wood, while imidacloprid-preserved wood was lighter. After 1-year exposure, furfurylated wood samples appeared to have the highest resistance to subterranean termite attack. These samples had minimal weight loss, indicating a substantial protection level. Imidacloprid-preserved wood had less resistance to termite attack, but was more resistant than untreated wood.

On Pre-Stressed Hull Structures

“Wave-piercing” super-planing trimaran with air-born unloading, WPT, is developing of “wave-piercing” catamaran, WPC, for twice bigger achievable speeds. As all fast vessels, WPT needs for minimal weight of hull structures. Using of pre-stressed structures is a novel method of hull weight decreasing. An example of such structure of WPT begins from external load estimation. And the scheme of pre-stressed structure is selected: two pairs of steel ropes along and across the WPT above-water structure. Than method of pre-strength is selected: constant or varied forces. Varied external loads define the need of varied pre-stress control. Estimation of the corresponded system weight: total structure of above-water platform can be decreased at about 20%. The method can be applied for airplane wings too.

Rules For Quality Storage Of Grapes

An in-depth study of the biological and physiological processes involved in the storage of grapes, as well as a clear idea about them, is important for the quality of the product. To preserve the quality of grapes, it is necessary to know what processes take place in them during storage and what factors of the external environment affect the course of these processes. The fact that grapes do not lose their quality over some time and lose minimal weight determines their durability. Storage resistance of grapes is determined by their shelf life in favourable conditions. The ability of grapes to be stored in a certain zone and season, as well as in agro-technical and technological regimes is called preservation. Storage is usually defined as the percentage of the weight loss of a product during storage.

Design of Magnetic Focusing system for a Compact Ka band Helix TWT

In this paper we discuss the design of Magnetic focusing system (MFS) for a compact helix travelling wave tube (TWT) operating in Ka-band. Issues related to the design of the magnetic focusing system have been discussed in detail along with practical measurement results. The key design parameters considered for this TWT are: the cathode voltage is around 9.3kV, beam current is 200mA and total length of the tube not more than 6 inch with minimal weight.

An Efficient Shortest Path Algorithm: Multi-Destinations in an Indoor Environment

The shortest path-searching with the minimal weight for multiple destinations is a crucial need in an indoor applications, especially in supermarkets, warehouses, libraries, etc. However, when it is used for multiple item searches, its weight becomes higher as it searches only the shortest path between the single sources to each destination item separately. If the conventional Dijkstra algorithm is modified to multi-destination mode then the weight is decreased, but the output path is not considered as the real shortest path among multiple destinations items. Our proposed algorithm is more efficient for finding the shortest path among multiple destination items with minimum weight, compared to the single source single destination and modified multi-destinations of Dijkstra’s algorithm. In this research, our proposed method has been validated by real-world data as well as by simulated random solutions. Our advancement is more applicable in indoor environment applications based on multiple items or destinations searching.

Design and Optimization of 200 Ton H- Type Hydraulic Press

A hydraulic press is a machine using a hydraulic cylinder to generate a compressive force. The hydraulic press works on Pascal’s principle, which states that the pressure throughout a closed system is constant. Hydraulic presses are commonly used for forging, clinching, moulding, blanking, punching, deep drawings and metal forming operations.200-ton capacity hydraulic frame and cylinder are modelled using Solidworks and analysed by solidworks simulation using finite element analysis. The objective of the project is to optimize the total mass and cost of hydraulic press while assuring adequate stiffness by using honeycomb structure on ram. Honey comb structures allows the minimization of material used to reach minimal weight and minimal material cost by providing high strength without compromising the output quality.