Evaluation of the pressure dependence of the cycle durability and thermodynamics of a metal hydride compressor composed of ternary V40 and V70TiCr

In this study, the cycle durability and thermodynamic characteristics of V₄₀TiCr and V₇₀TiCr were examined to evaluate their performance as metal hydride compressors. The cycles of incomplete hydrogen absorption under low pressure increased the hysteresis in the higher hydrogen concentration region, wherein cycling was not conducted, thereby forming an unavailable region; however, the equilibrium absorption pressure recovered after several full cycles at higher pressure. Due to the thermodynamic evaluation after 300 full cycles, V₄₀TiCr with 0.70, 0.53, and 0.44 of Ti/Cr ratio are expected to compress 1.2 wt% of hydrogen from 0.25 to 4.9 MPa, 1.96–22.2 MPa, and 5.97–46.8 MPa, respectively, between 40 and 150 °C. V₇₀TiCr with a low Ti/Cr ratio (0.33) demonstrated good cycle durability and is expected to compress 1.7 wt% of hydrogen 10 times from 5.4 to 54.8 MPa between 35 and 155 °C.     

Productivity and physiological responses during exposure to varying air temperatures and clothing conditions

This study assessed the effects of clothing and air temperature combinations on workplace productivity and physiological response. Ten male Japanese subjects were exposed to six combinations of clothing (0.3 clo and 0.9 clo) and air temperature (16°C, 26°C, and 36°C) during which cognitive performance (Bourdon and calculation tests), manual motor performance (finger-tapping test), and physiological responses (heart rate, blood pressure, and skin and oral temperatures) were measured. Both cold exposure and lower clothing levels likely increased the Bourdon test performance. Calculation test performance tended to be affected by exposure to cold or neutral temperatures at the beginning of the test. Cold exposure undermined manual motor performance (especially when combined with fewer clothing items) while heat exposure significantly increased heart rate. Both cold exposure and higher clothing level during heat exposure increased blood pressure. Body temperature, particularly mean skin temperature, increased with higher air temperature and was significantly influenced by clothing insulation during cold exposure. These results provide novel evidence for the effects of clothing and air temperature (particularly cold) on human productivity and physiological responses in humans.     

Democracy under uncertainty: The wisdom of crowds and the free-rider problem in group decision making.

We introduce a game theory model of individual decisions to cooperate by contributing personal resources to group decisions versus by free riding on the contributions of other members. In contrast to most public-goods games that assume group returns are linear in individual contributions, the present model assumes decreasing marginal group production as a function of aggregate individual contributions. This diminishing marginal returns assumption is more realistic and generates starkly different predictions compared to the linear model. One important implication is that, under most conditions, there exist equilibria where some, but not all, members of a group contribute, even with completely self-interested motives. An agent-based simulation confirmed the individual and group advantages of the equilibria in which behavioral asymmetry emerges from a game structure that is a priori perfectly symmetric for all agents (all agents have the same payoff function and action space but take different actions in equilibria). A behavioral experiment demonstrated that cooperators and free riders coexist in a stable manner in groups performing with the nonlinear production function. A collateral result demonstrated that, compared to a dictatorial decision scheme guided by the best member in a group, the majority/plurality decision rules can pool information effectively and produce greater individual net welfare at equilibrium, even if free riding is not sanctioned. This is an original proof that cooperation in ad hoc decision-making groups can be understood in terms of self-interested motivations and that, despite the free-rider problem, majority/plurality decision rules can function robustly as simple, efficient social decision heuristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Study of crescent shaped alignment marks applicable to self-alignment of micro-parts with and without positive and negative poles

A “crescent-shaped” binding alignment mark, more applicable to the self-alignment than reported “tear-drop/elliptical hole” pattern, has been designed and comparatively studied with other possible alignment marks. In order to further apply this novel design to micro-parts with positive and negative poles on the binding sites, a modified “crescent-shaped” pattern with an insulated space area, defined as “crescent-shaped/interval” for self-alignment of micro-parts with two poles has been therefore proposed and discussed. The fabrication process using micromachining has been studied and both the substrates and micro-parts with alignment marks have been fabricated for next self-alignment verification.     

Efficient Continuous Production of Lactulose Syrup by Alkaline Isomerization Using an Organogermanium Compound

Lactulose, a keto-type disaccharide widely used in pharmaceuticals and functional foods, is produced by the isomerization of lactose. The organogermanium compound poly-trans-[(2-carboxyethyl) germasesquioxane] (Ge-132) is an effective reaction promoter for the conversion of lactose to lactulose because of its high affinity to ketoses. Herein, an effective method for the continuous production of lactulose syrup was developed using Ge-132 through the alkaline isomerization of lactose in a bench-scale plant. This plant carried out a continuous isomerization process using Ge-132, continuous two-step separation process for separating the sugar and Ge-132, a continuous purification and concentration processes for the lactulose syrup, and separation and purification processes for the recovery of Ge-132. In this bench-scale plant, lactulose-containing syrup (350 g/L lactulose, 92 g/L lactose, and 31 g/L galactose) was prepared. The syrup was produced at a rate of 37.7 mL/h, and the content of residual Ge-132 in the syrup was 2 mg/L. The separation process was a two-step separation system requiring an ordinary electrodialyzer and an electro deionizer, which allowed the separation of more than 99.6 % Ge-132 from the reaction mixture. Moreover, the majority of Ge-132 and sodium hydroxide were recovered through electrodialysis using a bipolar membrane. The proposed system is the first to represent the novel development of an effective continuous production system for lactulose-containing syrup on the basis of the use of organogermanium compounds and incorporation of the electrodialysis technology.     

New Retainer Material for High Speed and High Temperature Cylindrical Roller Bearing

Cylindrical roller bearings are being developed which can operate over 300°C and greater than three million DN for innovative gas-generators. Under such severe conditions, it is necessary for retainers to be frictionless, lightweight and strong. After preliminary testing, SiC particle reinforced aluminum alloy composite appeared to have good friction and wear properties. It's specific gravity is about one-third of the present material in use, silver-coated SAE4340. In the course of the study, two different friction and wear tests were conducted to investigate the optimum volume fraction of SiC. The results indicated that the most efficient volume fraction was 20vol%. The tensile strength of Al-20vol%SiC was about 140MPa at 300°C. Based on the results of FEM analysis, 140MPa is considered sufficient to endure any stress concentration caused by tensile hoop stresses up to four million DN.     

Large distance flow-slide at Jono-Oge due to the 2018 Sulawesi Earthquake,Indonesia

There was a shallow earthquake in the Central Sulawesi province of Sulawesi island of Indonesia with a moment magnitude (Mw) 7.5 on 28th September 2018 at 18:02:44 local time. The event was preceded by major foreshocks and followed by aftershocks of significant magnitude. The epicenter of the main shock was in the Donggala regency of Minahasa peninsula of Central Sulawesi, approximately 70 km from the provincial capital of Palu. The earthquake was caused by the tectonic movement of the left lateral Palu- Koro fault within the Molucca Sea microplate, triggering major geotechnical failure and structural damage in Palu city and Sigi regency. Thousands of people died or are still unaccounted for, and countless others were injured. Balaroa, Petobo, Jono-Oge and Sibalaya were the worst hit mainly due to large-scale flow-slides and mud flows. It was the first time that such large-scale flow failures were triggered by an earthquake, and that the failure of very gentle sloping ground swept away whole localities. The objective of this research was to provide insight into the scale of ground failure and other infrastructural damage caused by the event, especially in Jono-Oge area, where the flow distance was longest. The authors performed preliminary and detailed surveys in the area twice by conducting Portable Dynamics Cone Penetration Test (PDCPT), collecting disturbed and undisturbed samples and using aerial drone (UAV) photography. The findings of the reconnaissance survey are described here along with subsequent data interpretation. Finally, the mechanism of the flow-slides is discussed.     

Evaluation of 400 low background 10-in. photo-multiplier tubes for the Double Chooz experiment

The Double Chooz is a reactor neutrino experiment which measures the last unknown neutrino mixing angle θ₁₃. The Double Chooz experiment uses two identical detectors placed at sites far and near from Chooz reactor cores. The detector uses 390 low-background and high performance 10-in. Photo-Multiplier Tubes (PMTs) to detect scintillation light from gadolinium loaded liquid scintillator. In order to test and characterize the PMTs and to tune operation parameter, we developed two types of PMT test system and evaluated 400 PMTs before installation. Those PMTs fulfilled our requirements and half of them were installed in the far detector in 2009 and physics data have been successfully taken since 2011.