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

Effect of accelerators on Ca(OH)2 activated ground granulated blast-furnace slag at low curing temperature

The early effects of three accelerators on a Ca(OH)2 activated ground granulated blast-furnace slag binder at low curing temperatures are discussed. The compressive strength, hydration kinetics, hydration products, and microstructures were investigated by isothermal calorimetry, X-ray diffraction, mercury intrusion porosimetry, scanning electron microscopy, and nuclear magnetic resonance. Results show that accelerators continue to promote the strength development of pastes in the early stage during low-temperature curing, especially with sodium sulfate, which exhibits a higher strength and hydration degree in the early stage. However, accelerators cannot effectively improve the pore structure at low-temperature curing, which severely restricts the development of strength, compared with that at 20 degrees C. Furthermore, a good correlation was found between the initial strength development and the limit equivalent ionic conductivity (LEIC), suggesting that LEIC influences the reaction acceleration of blast-furnace slag at an early age

Electrical Conductivity and Chloride Ingress in Hardened Cement Paste

The transport properties of hardened cement paste (HCP) have been investigated in many studies; the AC impedance method (ACI) is a non-destructive technique employed for this purpose and has been used in investigations of the electrical characteristic and mass transport properties of HCP. However, there are relatively fewer studies investigating chloride ingress in HCP and using the ACI. In this study, the relationship between the electrical conductivity measured by the ACI and chloride ingress was investigated. Backscattered electron image analysis and mercury intrusion porosimetry and water porosity were used to measure the pore structure of HCP, and the chloride ingress depth was measured by an electron probe microanalyzer. There was a high correlation between the porosity and conductivity and between the conductivity and diffusion coefficient of the chloride ions in HCP. This implies that the diffusion coefficient of chloride ions could be estimated by the conductivity measurements

Effect of alkali activators on diffusivity of metakaolin-based geopolymers

A basic investigation into whether a geopolymer can be utilized as a part of an artificial barrier during radioactive waste disposal was conducted in this study. Geopolymers are comprised primarily alumina and silica, and they exhibit negligible leaching owing to the absence of calcium. Studies on geopolymers are limited compared to those on other cementitious materials because the physical characteristics of geopolymers vary with the production conditions. In this work, metakaolin based geopolymers were prepared, and their diffusion performance was analyzed. The results indicate that the diffusivity of cesium in a geopolymer is affected by the type of alkali activator. Sodium-activated geopolymers had higher cesium adsorption capacity than potassium-activated geopolymers. The cesium adsorption capacity also had a significant effect on the diffusivity of cesium in the geopolymers. It was shown that, in addition to the pore structure and surface area, the mobility of water affects the diffusion performance of the geopolymer

Verification of a simplified disk diffusion method for antimicrobial susceptibility testing of bovine mastitis isolates

Bovine mastitis is mainly treated with antimicrobials. Determination of antimicrobial treatments based on the results of an antimicrobial susceptibility test is important to reduce the risk of emergence of antimicrobial resistance and to provide effective treatment. In Japan, not only the standardized agar disk diffusion method (standardized-ADD) based on Clinical and Laboratory Standards Institute guidelines, but also the agar disk diffusion method further simplified (simplified-ADD) are widely used as antimicrobial susceptibility tests for bovine mastitis isolates in the clinical laboratory. However, whether the simplified-ADD is a useful alternative to the standardized-ADD has not yet been sufficiently verified. Therefore, to verify the usefulness of the simplified-ADD, we compared the results of the standardized-ADD and the simplified-ADD using clinical isolates of bovine mastitis. Following testing of 83 isolates from 11 bacterial species, the correlation coefficient of the disk zone diameters in both methods was 0.92, indicating that the simplified-ADD is effective as an alternative method to the standardized-ADD. However, because the disk zone diameter tended to be smaller in the simplified-ADD than in the standardized-ADD, sufficient attention should be paid to this point when determining the treatment for clinical cases of mastitis from the results of the simplified-ADD. The fact that a difference in the results between the two methods was present means that the results cannot be interpreted based on the same criteria. Therefore, determination of the criteria appropriate for the simplified-ADD is needed

Functional and field performance of epoxy asphalt technology-state-of-the-art

There is an increasing demand for high strength and more durable materials in the asphalt technology market. In response to the demand, epoxy asphalt mixture (EAM) is one relatively new technology for use as a paving material in flexible pavements. There are various research works carried out on the laboratory and field performance of EAM. However, comprehensive research covering functional and field (F&F) performance of EAM is lacking. The main purpose of this review is to bridge this gap via the analysis of the functional properties of EAM. Consequently, the field performance of EAM in different case studies is reviewed and the serviceability of EAM in various transportation infrastructure is investigated. This paper also reviews the life cycle cost and maintenance of EAM. The major findings indicate that EAM shows superior F&F performance compared to the traditional hot and warm asphalt mixture. Additionally, the use of EAM is beneficial in the structure of pavements in tunnels and on bridge decks. In conclusion, the higher F&F performance of EAM supports the development of better performing pavements for various applications

Effect of retarders on flow and strength development of alkali-activated fly ash/blast furnace slag composite

Geopolymer concrete presents a major problem regarding its practical application, in that the geopolymer paste has very short setting time. Previous studies have shown that the addition of blast furnace slag to geopolymer paste considerably shortens the setting time. Based on these findings, in the present study, setting retarders were used to lengthen the setting time of the geopolymer paste. The objective of the present study was to identify the effect of a setting retarder on the fluidity and compressive strength of alkali-activated fly ash/blast furnace slag-based materials. It was shown that, by adding a chelator as a retarder, the setting time can be prolonged. However, the setting time was found to be dependent on the type of chelator. Similarly, the compressive strength development of the geopolymer was also found to be dependent on the type of chelator. It was clarified that the concentration of calcium and aluminum in solution during hardening changes with the addition of a chelator, and it was shown that there is a correlation between the concentrations of calcium and aluminum and the setting time

Rheological characteristics of epoxy asphalt binders and engineering properties of epoxy asphalt mixtures - state-of-the-art

The asphalt industry is aiming to produce high-quality materials and efficient technologies for pavement construction. One such technology that attracts attention is epoxy asphalt. This paper discussed the concepts, theories and engineering properties of epoxy asphalt technology and products. As the initial step, the chemical structure of epoxy materials was explained. Then principles of epoxy asphalt technology were discussed. Subsequently, the rheological characteristics of epoxy asphalt binder (EAB) were characterised. Engineering properties of an epoxy asphalt mixture (EAM) were then evaluated. The results indicated that EAB has better rheological properties than the traditional modified and net asphalts. Moreover, the results showed that superior structural performance of EAM compared with the traditional hot and warm mixtures. However, recyclability, initial strength and total cost of pavement construction remain matters of concern