Students Exposure to Sustainable Thermal Energy Storage Technologies at West Texas A&M University

In the mechanical and civil engineering programs at West Texas A&M University, students are exposed to a variety of sustainability-oriented projects through senior design and research courses. The projects are selected to provide an in-depth understanding of the investigated area through analytical and experimental studies. In this particular project, students in thermal design were asked to investigate the feasibility of using paraffin-oil mixture as a phase change material (PCM) in residential walls. A PCM material with a melting point of 23°C (73°F) was designed and mixed. The mass of PCM required for a 1 m2 (10.8 ft2) wall (the size of the test apparatus) was determined to be 5.8 kg (12.8 lb) in a vertical 3.18 cm (1.25 in) thick sheet. A wall containing the PCM and another wall designated as a “control” were placed on 1 meter cubic insulated structures and were monitored through controlled experimentation. The testing was conducted indoors and an interior heating element simulated four complete day cycles. The result of the indoor study proved conclusively that with the correct modifications and optimization, PCM, as a form of insulation, is economically viable over its lifespan of 20 years. The reduced cost to the owner of a 186 m2 (2,000 ft2) home is $129.73/year. The proposed design causes a minuscule 5.76 kg/m2 (1.2 lb/ft2) of additional load to the structure. Because the PCM is in the configuration of a uniform sheet, the majority of the extra load will be supported by the concrete slab of the home.Cockrell School of Engineerin

Experimental Heat Transfer Study on Green Roofs in a Semiarid Climate During Summer

An experimental study was conducted on green roofs under the semiarid summer climatic conditions of West Texas to investigate the effect of soil type, moisture content, and the presence of a top soil grass layer on the conductive heat transfer through the roof. Two soil types were investigated: uniform sand and local silt clay. Tests were also conducted on a control roof. A dual-needle heat-pulse sensor was used to conduct thermal property tests on the soils. The tests reveal that unlike sand, the thermal conductivity of silt clay did not increase continuously with soil moisture. Better heat transfer conditions were achieved when the sand and silt clay roofs were watered to a water depth of 10 mm per day rather than double the amount of 20 mm per day. The roof with silt clay soil had the lowest fluctuation in inner temperature between daytime and nighttime. Green roofs with silt clay soil required more than twice the amount of soil moisture than green roofs with sand to achieve similar roof heat transfer rates. The best net heat flux gains for vegetated green roofs were 4.7 W/m2 for the sand roof and 7.8 W/m2 for the silt clay roof

Structural Behavior and Design of Barrier-Overhang Connection in Concrete Bridge Superstructures Using AASHTO LRFD Method

The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application of National Cooperative Highway Research Program crash test is reviewed. The failure mechanism, design philosophy and load cases including extreme event limit states for barrier and overhang are discussed. The overhang design for the combined effect of bending moment and axial tension is probably the most important part of the design process. The overhang might be a critical design point of the deck with significantly higher amount of reinforcement. The design process becomes complicated due to combined force effect, LRFD crash test level requirement and the existence of several load combinations. Using this program, different LRFD load combinations are plotted together with the interaction diagram and the design is validated

Optimization of Post-Tensioned Box Girder Bridges with Special Reference to Use of High-Strength Concrete Using AASHTO LRFD Method

With the Federal Highway Administration-mandated implementation of the LRFD specifications, many state departments of transportation (DOTs) have already started implementing LRFD specifications as developed by the AASHTO. Many aspects of the LRFD specifications are being investigated by DOTs and researchers in order for seamless implementation for design and analysis purposes. This paper presents the investigation on several design aspects of post-tensioned box girder bridges designed by LRFD Specifications using conventional or High-Strength Concrete (HSC). A computer spreadsheet application was specifically developed for this investigation. It is capable of analysis, design, and cost evaluation of the superstructure for a cast-in-place post-tensioned box girder bridge. Optimal design of a post-tensioned box girder is achievable by correct selection of design variables. Cost evaluation of superstructures with different geometrical and material configurations has led to the development of optimum design charts for these types of superstructures. Variables used to develop these charts include, among others, span length, section depth, web spacing, tendon profile, and concrete strength. It was observed that HSC enables the achievement of significantly longer span lengths and/or longer web spacing that is not achievable when using normal strength concrete

A Star in the Brainstem Reveals the First Step of Cortical Magnification

A fundamental question in the neurosciences is how central nervous system (CNS) space is allocated to different sensory inputs. Yet it is difficult to measure innervation density and corresponding representational areas in the CNS of most species. These measurements can be made in star-nosed moles (Condylura cristata) because the cortical representation of nasal rays is visible in flattened sections and afferents from each ray can be counted. Here we used electrophysiological recordings combined with sections of the brainstem to identify a large, visible star representation in the principal sensory nucleus (PrV). PrV was greatly expanded and bulged out of the brainstem rostrally to partially invade the trigeminal nerve. The star representation was a distinct PrV subnucleus containing 11 modules, each representing one of the nasal rays. The 11 PrV ray representations were reconstructed to obtain volumes and the largest module corresponded to ray 11, the mole's tactile fovea. These measures were compared to fiber counts and primary cortical areas from a previous investigation. PrV ray volumes were closely correlated with the number of afferents from each ray, but afferents from the behaviorally most important, 11th ray were preferentially over-represented. This over-representation at the brainstem level was much less than at the cortical level. Our results indicate that PrV provides the first step in magnifying CNS representations of important afferents, but additional magnification occurs at higher levels. The early development of the 11th, foveal appendage could provide a mechanism for the most important afferents to capture the most CNS space

Analysis of Internet Visitors on Educational Websites

This study examines usage patterns of educational websites that employ databases, wikis, and general resources for information sharing and dissemination. To gather data about website usage, a quantitative survey was sent out to students and to the users of an existing educational website. Additionally, participants provided data on learning preferences and practices. Findings from the survey show that users visit an education website for finding information and getting connected to a community. The survey results also show that while communicating information should remain a top priority, educational web sites will need to adapt to an increasing desire for interpersonal communication within their own online communities

Developing strategic partnerships through a sustainability enrichment week

This paper describes the development of a mini-module focused on sustainability and timber engineering as a component of a strategic partnership designed to broaden Transnational Education, increase staff/student mobility, and further develop industry and community links within two universities. Edinburgh Napier University (ENU) draws students from around the world and is internationally recognised for timber construction and wood science. The New Model Institute for Technology and Engineering (NMITE) is a new higher education provider in England pioneering an innovative approach to engineering education integrating business, engineering, the liberal arts, and professional skills. ENU and NMITE leveraged these strengths to develop a strategic partnership that brings together staff, students, industry, and the community for opportunities that create impact beyond traditional learning approaches. This can be seen through the development of a Sustainability Enrichment Week hosted by NMITE’s Centre for Advanced Timber Technology (CATT) and attended by ENU Master’s in Environmental Sustainability students. Students investigated interfaces between buildings, humans, and nature through experiential learning based around the construction of the CATT building, which has been developed as a Living Lab. Each day featured activities aligned to identified learning outcomes and was themed around one of five sustainability competencies: systems thinking, values thinking, strategic thinking, future thinking, and collaboration. The Sustainability Enrichment Week also served as a trial for a short course soon to be offered as part of a Timber Technology, Engineering, and Design programme. This project could be a model for other universities seeking to create similar strategic partnerships and learning experiences

Cellular Scaling Rules of Insectivore Brains

Insectivores represent extremes in mammalian body size and brain size, retaining various “primitive” morphological characteristics, and some species of Insectivora are thought to share similarities with small-bodied ancestral eutherians. This raises the possibility that insectivore brains differ from other taxa, including rodents and primates, in cellular scaling properties. Here we examine the cellular scaling rules for insectivore brains and demonstrate that insectivore scaling rules overlap somewhat with those for rodents and primates such that the insectivore cortex shares scaling rules with rodents (increasing faster in size than in numbers of neurons), but the insectivore cerebellum shares scaling rules with primates (increasing isometrically). Brain structures pooled as “remaining areas” appear to scale similarly across all three mammalian orders with respect to numbers of neurons, and the numbers of non-neurons appear to scale similarly across all brain structures for all three orders. Therefore, common scaling rules exist, to different extents, between insectivore, rodent, and primate brain regions, and it is hypothesized that insectivores represent the common aspects of each order. The olfactory bulbs of insectivores, however, offer a noteworthy exception in that neuronal density increases linearly with increasing structure mass. This implies that the average neuronal cell size decreases with increasing olfactory bulb mass in order to accommodate greater neuronal density, and represents the first documentation of a brain structure gaining neurons at a greater rate than mass. This might allow insectivore brains to concentrate more neurons within the olfactory bulbs without a prohibitively large and metabolically costly increase in structure mass

Characteristics of dust event in East Asia : Focus on the Gobi Desert, and Mongolia regions

[ABSTRACT] This study investigated the effect of snow and vegetation covers on dust emission by the correlation analysis of strong wind frequency and dust emission frequency, where the strong wind is defined with a constant threshold 6.5 m/sec. This correlation should be high (low) where the variance of land surface environment is low (large). In addition to this idea, referring to the parameterizations of threshold wind speed by NDVI and snow cover fraction, we built four hypotheses as shown in section 3.1. However, our obtained results disagreed with these in many points, and this indicates problems in the current parameterizations. We will discuss the reasons of these disagreements and some methods will be proposed to clarify these problems