Development and a SEU Test of a TDC LSI for the ATLAS Muon Detector

A new TDC LSI (AMT-2) for the ATLAS Muon detector has been developed. The AMT-2 chip is a successor of the previous prototype chip (AMT-1). The design of the chip was polished up for aiming mass production of 20,000 chips in year 2002. Especially, power consumption of the chip was reduced to less than half of the previous chip by introducing newly developed LVDS receivers. The AMT-2 was processed in a 0.3 mu m CMOS Gate-Array technology. It achieved 300 ps timing resolution and includes several data buffers, trigger matching circuit, JTAG interface and so on. First SEU test by using a proton beam was recently performed. Although the test results are very preliminary at present stage, we get very low SEU rate safely used in ATLAS environment. (7 refs)

Criminology in the System of Scientific Knowledge

Changes in the social, political and economic development of society contribute to the development of sciences. Criminology is not an exception. The genesis and the current state of scientific views on the nature of inter-scientific links of criminology, the essence of its nature, its place in the system of sciences have been considered. The attention has been focused on the fact that these problems are interrelated and remain ones of the most debatable in the general theory of criminology. It has been established that domestic criminology is developing gradually, has logical change of the system, transits from one state to more perfect state. It has been stated that throughout the history of the development of criminology, different views were expressed regarding its nature. At the same time, not only scientific concepts, but also personal views of individual scientists changed repeatedly. Attention is drawn to the fact that, so far, criminologists have not reached an agreed position on these issues. Criminology implies using of the creative approach, situation conditionality, presence of alternatives when choosing certain ways, means, methods or techniques. It has been established that efficiency of investigation of robberies and brigandage depends on correct determination of an investigative situation; proposing and refining of all possible versions; organisation of interaction of an investigator with operational units. Therefore, she is associated with different sciences. Currently, two basic concepts coexist regarding the nature of criminology, according to one of them criminology is recognised as a special science of law, and according to the other – a science of synthetic (integral) nature. It has been concluded that criminology, based on the subject of the study, its nature and objectives, integrates the knowledge of legal, technical and natural sciences. At the same time, criminology is a unified fusion of knowledge, not an aggregate of sciences, since it is not possible to single out purely legal, natural or technical sections, that is, knowledge complexes as any fixed structures, which once again testifies the synthetic (integral) nature of its origin

Recycling of calcined carbonated cement pastes as cementitious materials: Proposed CCUS technology for calcium looping

In this study, calcined carbonated hydrated cement pastes (HCPs) were used to partially replace ordinary Portland cement (OPC) as a cementitious material. Calcined carbonated HCP can be derived from carbonated HCP after the release of CO2 for the carbon capture, utilization, and storage (CCUS). Calcined carbonated HCP was produced by calcining carbonated HCP at 1000 degrees C, also used in calcium looping. The crystal phase compositions of the HCP, carbonated HCP, and calcined carbonated HCP were identified. Various hardening and microstructural tests on the composite cement paste mixtures blended with calcined carbonated HCP were performed. The initial results showed that the HCP could sequester CO2, forming various calcium carbonates. After carbonated HCP calcination, the main nanocrystalline phases of calcium silicate hydrate (C-S-H) and calcium carbonate decomposed, forming lime and wollastonite. The 28-day compressive strength of the calcined carbonated HCP-OPC mixtures increased with the replacement ratio up to 20%, owing to the filler effect of wollastonite. The microstructural analysis revealed that the portlandite, C-S-H, and monocarboaluminate phases were formed after hydration. Finally, by recycling demolition waste, this study proposed a technology roadmap for CCUS to achieve this goal, and a life cycle assessment was conducted to evaluate and compare the environmental impacts of producing 1 t of calcined carbonated HCP-OPC mixtures and plain OPC paste

Ion-cement hydrate interactions govern multi-ionic transport model for cementitious materials

The main objective of this investigation is to describe the interaction between cement hydrates and electrolyte solution to understand multi-ionic transport in cementitious materials. A surface complexation model in PHREEQC including an electrostatic term is used to simulate the ionic adsorption on the calcium silicate hydrate (C-S-H) surface. The equilibrium constants for the adsorption of ions on C-S-H surfaces are obtained by fitting experimental data to the model. The adsorption of both divalent and mono-valent cations, and also anions significantly changes the surface charges of hydrated paste. Chloride is being held in a chemical binding as Friedel's salt and bound mainly by the adsorptive action of C-S-H. An integrated modelling approach employing a phase-equilibrium model, a surface complexation model, and a multi-component diffusion model has been developed in PHREEQC to simulate the multi-ionic transport through hydrated cement paste. It was found that the physical adsorption of ions on C-S-H, the size of pores, and the surface site density of C-S-H govern the rate of penetration of ionic species. Finally, the proposed model has been validated against chloride profiles measured in this study as well as with data available in the literature for hydrated cement paste

Prediction of the drying shrinkage of alkali-activated materials using artificial neural networks

Alkali-activated materials (AAMs) are qualitatively and quantitatively evaluated with an emphasis on the ultimate drying shrinkage. We systematically evaluated AAMs based on the mix design and curing conditions, utilizing a total of 452 AAM mixtures extracted from 44 papers. Finally, a predictive model for the ultimate drying shrinkage of AAMs was constructed using an artificial neural network (ANN) with high accuracy, in which the reactivity of binder, geopolymer paste volume, liquid-to-binder ratio, alkali activator modulus, aggregate volumetric ratio, curing temperature, relative humidity and specimen size were set as inputs. This model shows great generality by compiling various AAM mixtures and is easy-handling without preparation of samples for acquiring specific properties. Moreover, the efficiency of three commonly used models for predicting the drying shrinkage-the Bazant-Baweja model, Gardner and Lockman model, and multi-linear regression model-were evaluated and compared to the proposed ANN model, revealing a better prediction performance of ANN model. This study will advance the understanding of the drying shrinkage behaviors of AAMs and provide practical guidelines for designing AAM mixtures with high durability