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American Society for Testing and Materials

With digital equipment becoming increasingly networked, either on wired or wireless networks, for personal and professional use alike, distributed software systems have become a crucial element in information and communications technologies. The study of these systems forms the core of the ARLES' work, which is specifically concerned with defining new system software architectures, based on the use of emerging networking technologies. In this context, we concentrate on the study of distributed systems which bring to life the vision of ubiquitous computing systems, also known as ambient intelligence.

반도체 공정 overview

The influence of fiber type and length on the cracking resistance, durability and pore structure of face slab concrete

This paper presents the results of the fracture toughness of concretes containing two mineral additives. During the tests, the method of loading the specimens according to Mode I fracture was used. The research included an evaluation of mechanical parameters of concrete containing noncondensed silica fume (SF) in an amount of 10% and siliceous fly ash (FA) in the following amounts: 0%, 10% and 20%. The experiments were carried out on mature specimens, i.e., after 28 days of curing and specimens at an early age, i.e., after 3 and 7 days of curing. In the course of experiments, the effect of adding SF to the value of the critical stress intensity factor—KIcS in FA concretes in different periods of curing were evaluated. In addition, the basic strength parameters of concrete composites, i.e., compressive strength—fcm and splitting tensile strength—fctm, were measured. A novelty in the presented research is the evaluation of the fracture toughness of concretes with two mineral additives, assessed at an early age. During the tests, the structures of all composites and the nature of macroscopic crack propagation were also assessed. A modern and useful digital image correlation (DIC) technique was used to assess macroscopic cracks. Based on the conducted research, it was found the application of SF to FA concretes contributes to a significant increase in the fracture toughness of these materials at an early age. Moreover, on the basis of the obtained test results, it was found that the values of the critical stress intensity factor of analyzed concretes were convergent qualitatively with their strength parameters. It also has been demonstrated that in the first 28 days of concrete curing, the preferred solution is to replace cement with SF in the amount of 10% or to use a cement binder substitution with a combination of additives in proportions 10% SF + 10% FA. On the other hand, the composition of mineral additives in proportions 10% SF + 20% FA has a negative effect on the fracture mechanics parameters of concretes at an early age. Based on the analysis of the results of microstructural tests and the evaluation of the propagation of macroscopic cracks, it was established that along with the substitution of the cement binder with the combination of mineral additives, the composition of the cement matrix in these composites changes, which implies a different, i.e., quasi-plastic, behavior in the process of damage and destruction of the material.

Studies of Fracture Toughness in Concretes Containing Fly Ash and Silica Fume in the First 28 Days of Curing.

Due to the rapid growth of 3D printing popularity, including fused deposition modeling (FDM), as one of the most common technologies, the proper understanding of the process and influence of its parameters on resulting products is crucial for its development. One of the most crucial parameters of FDM printing is the raster angle and mutual arrangement of the following filament layers. Presented research work aims to evaluate different raster angles (45°, 55°, 55'°, 60° and 90°) on the static, as well as rarely investigated, dynamic mechanical properties of 3D printed acrylonitrile butadiene styrene (ABS) materials. Configuration named 55'° was based on the optimal winding angle in filament-wound pipes, which provides them exceptional mechanical performance and durability. Also in the case of 3D printed samples, it resulted in the best impact strength, comparing to other raster angles, despite relatively weaker tensile performance. Interestingly, all 3D printed samples showed surprisingly high values of impact strength considering their calculated brittleness, which provides new insights into understanding the mechanical performance of 3D printed structures. Simultaneously, it proves that, despite extensive research works related to FDM technology, there is still a lot of investigation required for a proper understanding of this process.

Static and Dynamic Mechanical Properties of 3D Printed ABS as a Function of Raster Angle.

As a new antiseepage reinforcement material, polyurethane grouting material has been widely studied in terms of its static mechanical properties. However, research on its dynamic mechanical properties is relatively rare. In this research, considering the influence of the explosive charge weight, the air contact and close-in explosion experiments of polymer slabs were carried out. The failure mode and damage spatial distribution characteristics of polymer slabs were explored. Pressure time history curve of air shock wave was obtained using an air shock wave tester. The influence of polymer slabs on the propagation of air explosion shock wave was compared and analyzed. The results show that, under the air contact explosion, the polymer slab mainly suffers local damage, while under close-in explosion, overall damage is the main damage mode. With the increase of the explosive charge weight, the failure mode of the polymer slab transits from surface crack and slight spalling to local and whole crushing.

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Experimental Study on the Damage Characteristics of Polymer Slabs Subjected to Air Contact and Close-In Explosions

Design method of polymer cut-off wall density for earth dams based on multi-objective optimization

Defects identification and location of underground space for ground penetrating radar based on deep learning

Failure characteristics analysis of crushed-stone-reinforced polymer (CSRP) composites under compressive load based on meso-mechanics

The invention discloses a visual intelligent rotary jet grouting method for repairing of a drainage pipeline. The method comprises steps as follows: S1, blocking two ends of the pipeline, and drainingwater in the pipeline; S2, connecting an integrated cable, and placing visual intelligent rotary jet grouting equipment into the pipeline; S3, starting the visual intelligent rotary jet grouting equipment by operating a control panel, starting grouting equipment, controlling the visual intelligent rotary jet grouting equipment to walk in the pipeline, and shooting image information in the pipeline by a front-view camera and a rear-view camera; S4, adjusting the front-view camera and an infrared distance meter to be aligned to a disease position when the disease occurs; S5, analyzing the typeand the degree of the disease according to signals detected by the infrared distance meter, and controlling spray nozzles of the visual intelligent rotary jet grouting equipment to repair the diseaseposition; S6, after repairing, starting the infrared distance meter again to detect and analyze the repairing position until the evaluation is qualified; and S7, repeating steps 3-6 until repairing ofthe whole pipeline is finished.

Hongyuan Fang

Papers

Experimental Study on the Damage Characteristics of Polymer Slabs Subjected to Air Contact and Close-In Explosions

Design method of polymer cut-off wall density for earth dams based on multi-objective optimization

Defects identification and location of underground space for ground penetrating radar based on deep learning

Failure characteristics analysis of crushed-stone-reinforced polymer (CSRP) composites under compressive load based on meso-mechanics

Visual intelligent rotary jet grouting method for repairing of drainage pipeline