A test method for evaluating the thermal environment of underground coal mine refuge alternatives

Since 2009, the Mine Safety and Health Administration(MSHA) has required mines to install refuge alternatives(RAs) in underground coal mines. One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment. In 30 CFR 7.504, the maximum allowable apparent temperature(AT) for an occupied RA is specified as 35 °C(95 °F). Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35 °C(95 °F) AT limit. For these tests, heat input devices are used to input the metabolic heat of actual miners. A wide variety of test methods, sensors, and heat input devices could be used when conducting such tests. Since 2012, the National Institute for Occupational Safety and Health(NIOSH) has conducted over thirty 96-hour heat/humidity tests on four different RAs. This paper discusses the test equipment and procedures used during these investigations. This information is useful for RA manufacturers conducting RA heat/humidity tests, for other researchers investigating RA heat/humidity buildup, and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.     

Entwicklung und Validierung eines Kühlmittelsensors zur Bewertung der Korrosionsschutzwirkung

A sophisticated thermal management is one of the main subsystems that enables combustion engines with high power density. In this context the demands on coolants are also increasing. There has to be a certain level of corrosion protection to ensure the functionality of the cooling system. Hereafter the result of an electrochemical sensor development is presented. With the knowledge of analytical and electrochemical results a quick test for characterizing coolants corrosion protection has been developed and validated.     

Maximum dry density test to quantify pumice content in natural soils

Crushable volcanic soils are well-known for their distinctive texture, vesicular nature and grain fragility. These features of volcanic soils lead to difficulty in interpreting the results of laboratory and field testing because of the occurrence of particle crushing. Sands containing pumice particles are commonly found in the Hamilton Basin in the North Island of New Zealand. The pumice particles originated from a series of volcanic eruptions centered in the Taupo and Rotorua regions. As a result of flooding and erosion along the Waikato River, the pumice particles have become mixed with other materials and have been distributed over the Hamilton Basin; these mixtures are referred to herein as natural pumiceous (NP) sands. This paper initially investigates an appropriate technique for measuring the maximum dry density (MDD) of NP sands; then a modified MDD test is proposed for estimating the pumice contents of these sands. In order to examine the applicability of different standard methods for determining MDD, New Zealand and Japanese standards are employed. The results using the Japanese standard show consistent MDD values when repeating the tests due to negligible particle crushing. On the other hand, the results of MDD tests according to the New Zealand standard indicate that a significant amount of particle crushing occurs after each repeated test and, consequently, it is not possible to get the same result when the test is repeated. NP sands reach their ultimate potential breakage during the modified MDD tests (at least, for the level of loading applied) and they experience different levels of particle crushing which may be a function of their pumice content. As a way forward, the relative breakages of the materials tested are used to estimate the pumice contents of the NP sands.     

A multi-agent architecture for outsourcing SMEs manufacturing supply chain

In the present, global and competitive market customer's demands are very volatile. It is very difficult for small and medium size enterprises (SMEs) to satisfy their customer with quality product in reasonable price. Large firms are spending huge amount of their budget in generating technology development. To cope with this competitive market, usually, SMEs concentrate on their core expertise and outsource some non-core items or activities. The outsourcing decision (when, what, whom) is very crucial for small-scale industries. Realizing this scenario, in this article, an automated self-adaptive multi-agent system has been proposed. The proposed system will help SMEs to take an appropriate decision to mitigate the uncertainty in supply chain. The developed system exploits the “Outsourcing of operations” feature by its agents to conclude the manufacturing processes faster and reduce the idle time of certain machines with less human intervention. The communication protocol for agents has been described to give an insight of their communication. It was explained how various agents like outsourcing, material planning and supplier selection will come into action at different stages and take appropriate outsourcing decisions. Therefore, this multi-agent architecture will facilitate small scale manufacturing industries to execute their manufacturing processes and complex logistics issues efficiently. The execution of proposed architecture has been described in the simulated case study.     

Nonlinear model-based track guidance of user-defined points at the vehicle front

Preventive pedestrian protection systems are validated by means of fully automated driving tests reproducing safety-critical traffic situations on a proving ground. In order to assess these preventive safety systems, a precise and reproducible collision of a pedestrian dummy with a specific point at the vehicle front, e.g., the left corner of the vehicle, must be ensured. Hence, a track guidance of this specific point is required. Beyond the state of the art a new nonlinear model describing the lateral deviation of any point at the vehicle front to a predefined path is proposed in this paper. Based on this model the method of input–output linearization is used to design a flexible lateral guidance system for an easy application in different vehicles. Furthermore, the closed-loop stability is proven and experimental results are presented.     

Consumer context-specific sensory acceptance tests: Effects of a cognitive warm-up on affective product discrimination

For simple hedonic ratings, product range effects often limit the reliability and accuracy of consumer affective discriminations among multiple products. In the present study, a cognitive warm-up (CWU) procedure was applied to consumer acceptance tests in order to stabilize consumers’ evaluative criteria by evoking their personal evaluation context. The effects of such procedure on the robustness of the affective product discriminations were investigated using two sets of comparison experiments, each using a related samples design. Consumers with equivalent sensory preference profile for skin lotions were screened and divided into High Reflection Thinkers (HRT) and Low Reflection Thinkers (LRT) using the Cognitive Reflection Test. They were then randomly, but evenly assigned to either a treatment (Group I) or a control (Group II) group, in which hedonic rating was performed either with or without the preceding CWU procedure, thus forming four sub-groups (treatment group-HRT, treatment group-LRT, control group-HRT, and control group-LRT subjects). For each sub-group, discriminability between the two chosen products in terms of d′ value was compared across the two experimental conditions consisting of different product ranges. The results indicated that only in the control group-LRT subjects, the two conditions displayed different product discrimination. It suggests that for LRT subjects who are assumed to be more intuitive and thus might be more vulnerable to such product range effects, the CWU had a stabilizing effect on the evaluative criteria, resulting in more robust product discrimination.     

Learning effectiveness of applying automated music composition software in the high grades of elementary school

The paper is mainly to explore the automated music composition experiences for the students in the high grades of elementary school who are unfamiliar with the professional music theory. The proposed Automated Composition for Music Education (ACME) software was developed to help the students to compose the rhythm and melody themselves, while chord configuration and arrangement are automatically generated. Subsequently, sixth-year students of a non-experimental school were recruited to use the software for the completion of its development. Analysis of learning effectiveness at the reaction level, analysis of learning-level learning effectiveness, correlation analysis of the reaction- and learning-levels learning effectiveness has been performed with a significant result. The correlations between each component of learning effectiveness at the reaction and learning levels were also found. Finally the students in the experimental group using the ACME teaching materials showed a better learning effectiveness at both reaction level and learning level, than those of the students in the comparison group.     

Energy dissipation capacity of fibre reinforced concrete under biaxial tension–compression load. Part I: Test equipment and work of fracture

The objective of this research was to analyse the differences in the dissipated energy under uniaxial tension and biaxial tension–compression load of fibre reinforced concretes using the Wedge Splitting Test. Under biaxial load the specimens were subjected to compressive stress ratios from 10% to 50% of the concrete compressive strength perpendicular to the direction of the tensile load.Under biaxial tension–compression load the energy dissipation capacity of the specimens decreases compared to the uniaxial tension load case on average 20–30%. It is believed that the decrease is a result of the damage mechanism of the concrete matrix and deterioration of the fibre–matrix and/or aggregate–cement paste interfaces in case the section is additionally loaded with compression stresses. This indicates that dimensioning of concrete elements under biaxial stress states using material parameters obtained from tests conducted on specimens under uniaxial tensile load is unsafe and could potentially lead to a non-conservative design.In the second part of this paper the extent of the fracture process zone under uniaxial tension and biaxial tension–compression load will be examined with the Acoustic Emission technique and the reasons for decrease of the energy dissipation capacity under biaxial load will be further discussed.     

Reduction of Escherichia coli O157:H7 and Salmonella Typhimurium DT 104 on fresh produce using an automated washer with near neutral electrolyzed (NEO) water and ultrasound

Automated produce washers can be a useful processing aid when treating fresh produce contaminated with pathogens. The use of near neutral pH electrolyzed (NEO) water as a wash or sanitizing solution has been shown to lead to significant reductions of Escherichia coli O157:H7 and Salmonella on fresh produce. To further enhance reported pathogen reductions, the effects of a combined NEO water (155 mg/L free chlorine, pH 6.5) and ultrasound wash protocol on lettuce and tomatoes inoculated with E. coli O157:H7 and S. Typhimurium DT 104 were studied. The effects of the pH of NEO water and washer agitation on pathogen reductions were also assessed. Inoculated tomatoes and lettuce leaves were treated with either chilled deionized water or NEO water, with or without 20 kHz ultrasound (130 W and 210 W). Tomatoes were treated for 1, 3 and 5 min while lettuce was treated for 5, 10 and 15 min. Ultrasound significantly increased the oxidation-reduction potential (ORP) of NEO water (p < 0.05) but did not affect the pH and free chlorine concentration (p > 0.05). Increased washing time and higher ultrasonic power led to significantly greater reductions of both pathogens on produce items (p < 0.05). NEO water combined with 210 W ultrasonication for 15 min led to 4.4 and 4.3 log reductions of E. coli O157:H7 and S. Typhimurium on lettuce, respectively, while 210 W ultrasound for 5 min completely inactivated both pathogens on tomatoes. Both pathogens were completely inactivated in NEO water solutions, suggesting that its use presents little chance of cross-contamination.