MATERIAL MOVEMENT WITHIN A SINGLE-SCREW EXTRUDER

In present-day economic conditions, extrusion is one of the advanced feedstuffs and food production processes involving intensive manifold heat and force action. During extrusion, the main function is performed by a compression mechanism which includes a forcing screw unit built into the cylinder (cowling). The forcing mechanism performs the task of transferring material while concurrently compressing it up to a required pressure and increasing the material’s temperature due to compression and friction against the cowling's sides. In our view, the first technique is appropriate when a material which is moving within the compression area is in viscous-flow state. The second technique is optimal for theoretical description of areas of loading, transportation, and compression (melting) where the working pressure is maintained.

Structural transformation and dynamical heterogeneity in Germania melt under compression: molecular dynamic simulation

The structural transformation and dynamical heterogeneity in Germania (GeO2) are investigated via molecular dynamics (MD) simulation. The MD model with 5499 atoms was constructed under pressure up to 150 GPa and at a temperature of 3500 K. The structural transformation mechanism has been studied by observing domain structures and boundary oxygen atoms. The simulation result reveals that GeO2 consists of separate domains and boundaries in its melt structure. Under compression, the structure of GeO2 changes gradually and represents many types of structures. The melt structure exhibits many structural domains Dx, and polymorphism appears at pressures of 12 and 20 GPa. The change of tetrahedral structure to octahedral structure in germanium coordination occurred in parallel with the process of merging and splitting of domain structure. Moreover, the existence of high- and low-density phases in GeO2 melt is indicated. The high-density phase is D6 domain and boundary oxygen while the low-density phase is D4 and D5 domain. The compression mechanism in GeO2 melt mainly is a reduction of average Voronoi volume of oxygen and Voronoi volume of D6, boundary atoms oxygen. Furthermore, we find the dynamical heterogeneity at ambient pressure. The separate “fast” regions and “slow” regions in GeO2 are detected via link-cluster function.

Research on reliable sealing technology of spacecraft rectangular hatch based on boundary control

In view of the large size of the sealing surface of the space large diameter rectangular cabin door, the large number of locking mechanisms and long service life, it is difficult to adjust the multi degree of freedom attitude in the assembly process, the complex assembly and adjustment of the mechanism, the synchronization accuracy is not easy to ensure, the consistency of the multi-point seal compression rate is high, and it is not easy to control. Based on the rotation law of the spatial linkage mechanism, the precise dimension chain control of the hatch is carried out, and the attitude of the multi degree of freedom linkage is adjusted to realize the synchronous compression of multiple compression units of the compression mechanism; Based on the minimum and maximum operating force as the boundary, through the sealing stress simulation, the “boundary control” coupling assembly and adjustment technology is proposed to optimize the sealing structure and realize rapid and efficient assembly. The results show that the vacuum leakage rate is still less than 2.5×10−3 PaL/s after 2000 door opening and closing tests and sealing compression ratio are better than 15%. The long-life test verifies the feasibility and effectiveness of this method, and forms a set of high reliable and long-life sealing assembly and adjustment method of space hatch, which provides technical guidance and reference for the subsequent assembly of similar space hatch mechanisms.

Real World Metamer Sets: Or How we Came to Love Noise

It is well known that color formation acts as a noise-reducing lossy compression mechanism that results in ambiguity, known as metamerism. Surfaces that match under one set of conditions-an illuminant and observer or capture device-can mismatch under others. The phenomenon has been studied extensively in the past, leading to important results like metamer mismatch volumes, color correction, reflectance estimation and the computation of metamer sets-sets of all possible reflectances that could result in a given sensor response. However, most of these approaches have three limitations: first, they simplify the problem and make assumptions about what reflectances can look like (i.e., being smooth, natural, residing in a subspace based on some measured data), second, they deal with strict mathematical metamerism and overlook noise or precision, and third, only isolated responses are considered without taking the context of a response into account. In this paper we address these limitations by outlining an approach that allows for the robust computation of approximate unconstrained metamer sets and exact unconstrained paramer sets. The notion of spatial or relational paramer sets that take neighboring responses into account, and applications to illuminant estimation and color constancy are also briefly discussed.

Stream-Based Lossless Data Compression

In this chapter, we introduce aspects of applying data-compression techniques. First, we study the background of recent communication data paths. The focus of this chapter is a fast lossless data-compression mechanism that handles data streams completely. A data stream comprises continuous data with no termination of the massive data generated by sources such as movies and sensors. In this chapter, we introduce LCA-SLT and LCA-DLT, which accept the data streams, as well as several implementations of these stream-based compression techniques. We also show optimization techniques for optimal implementation in hardware.

A Review on Research on Critical Analysis on Performance of RCC Structure under various Blast Condition

The main aim of this paper is design and implement Critical Analysis on Performance of RCC Structure Under Various Blast Condition. Advance in technology over the past few decades have necessitated the dynamic effect of loading blast such as wind and earthquake loads. The main purpose of this study is to gain access to materials on blast loads that can be designed, to assess vulnerabilities and to provides guidance to designed to economically reduce the impact of explosion on building and provide protection to human and infrastructure. A case study is performed on an RC column subject to blast loading; the effect of force on the deflection over time, the stress rate on the tensile is studies. The compression mechanism is studies by following the alternative path method for minimum design load for building and other structures. The 2-storey building is analyzed and the displacement and blast loading and standoff distance on the floor vehicles are studied by adding X-type brackets and shear wall to make them explosion resistant. Structural, architectural and managerial aspects of the design are also included in the report so that the structures become blast resistant.