A New Model for Evaluating the Future Options of Integrating Ground Source Heat Pumps in Building Construction

Decision-making for effective infrastructure integration is challenging because the performances of long-lasting objects often depends on conditions which are either outside the control of the designer or difficult to foresee at the design stage. In this paper we examine a new approach to estimating the range of cost-effective solutions for integrating the construction/retrofit of two or more different types of infrastructure. Infrastructure integration has many perceived benefits, but also faces serious new challenges and doubts from practitioners, particularly in sectors with complex construction process, long asset lives, uncertain cost parameters, and slow and unwieldy decision-making, such as is common with civil engineering works. We test all main options in integrating a ground source heat pump (GSHP) system with the construction and retrofit of an archetypal, office building. A new simulation model is developed and parameterized using actual data in the UK. We incorporate unavoidable uncertainties and randomness in how the decisions are triggered, and test the effectiveness of proactive measures to embed future options. The model highlights how sensitive the range of cost-effective solutions is to the setting of renewable energy incentives, discount rates, technical performance and life-cycle asset management of interdependent infrastructure. This points to a clear need for establishing appropriate regulatory standards. We expect this model to find increasing applications in the planning and designing of integrated complexes of buildings, transport facilities, renewable energy supply, water supply and waste management in dense urban areas, which are an increasingly key part of sustainable urban development

Effects of Soil Fabric on Undrained Behavior of Sands

The undrained behavior of sands in monotonic triaxial compression and extension tests was simulated using the Distinct Element Method (DEM). Soil specimens were prepared at different initial soil fabrics but at similar void ratios and the effects of soil fabric on the undrained behavior were investigated. The DEM results show that soil fabric and its change have profound effects on the undrained response of sands. They also provide some insights for the interpretation of the published experimental data that show the effects of specimen reconstitution methods and of preshearing on the undrained behavior of sands

The term "carcinoid" is a misnomer: the evidence based on local invasion

<p>Abstract</p> <p>Background</p> <p>Since Oberndorfer proposed the term "carcinoid" in 1907, over 100 years have passed. This attractive term was initially proposed for 6 cases of his own experience with 12 submucosal lesions in the small intestine.</p> <p>Oberndorfer summarized the characteristic features of these lesions as follows: (1) small in size and often multiple, (2) histologically undifferentiated with a suggestion of gland-formation, (3) well-defined without any tendency to infiltrate the surroundings, (4) no metastases, and (5) apparently slow-growing reaching no significant size with a seemingly harmless nature.</p> <p>Review</p> <p>This article stresses the malignant nature of "carcinoid" on the basis of local invasion prior to metastases in the first two sessions, (1) with Oberndorfer's original diagram, and (2) with an experimental observation on extraglandular microcarcinoid in a form of "budding".</p> <p>Next, (3) a statistical comparison between a carcinoid group and a non-carcinoid ordinary carcinoma group is introduced on metastasis rates at an early stage with two prescribed factors of the depth of invasion restricted within the submucosa (sm-lesion) and a small tumor size category of 1 cm to 2 cm: the carcinoid group exhibited metastasis rates higher than those in the ordinary carcinoma group when calculated in the stomach and rectum.</p> <p>In the author's experience, "carcinoids" are malignant not only in the gastrointestinal tract but also in the other sites on the basis of local invasion.</p> <p>Lastly, (4) discussion on the terminology of "carcinoid" as a misnomer is carried out.</p> <p>Adequate terms referring to the entity of this malignant tumor group are discussed. One of the most adequate and brief terms for "carcinoid" that is included now in neuroendocrine tumor group would be "endocrinocarcinoma" as per the author's proposal, followed by NEC (neuroendocrinocarcinoma) or GEC (gut endocrinocarcinoma).</p> <p>Conclusion</p> <p>The term "carcinoid" is a misnomer that can be confirmed on the basis of local invasion prior to metastases. "No metastases without local invasion" is not of a negligible importance.</p

Experimentally observed evolution between dynamic patterns and intrinsic localized modes in a driven nonlinear electrical cyclic lattice

Locked intrinsic localized modes (ILMs) and large amplitude lattice spatial modes (LSMs) have been experimentally measured for a driven 1-D nonlinear cyclic electric transmission line, where the nonlinear element is a saturable capacitor. Depending on the number of cells and electrical lattice damping a LSM of fixed shape can be tuned across the modal spectrum. Interestingly, by tuning the driver frequency away from this spectrum an LSM can be continuously converted into ILMs and visa versa. The differences in pattern formation between simulations and experimental findings are due to a low concentration of impurities. Through this novel nonlinear excitation and switching channel in cyclic lattices either energy balanced or unbalanced LSMs and ILMs may occur. Because of the general nature of these dynamical results for nonintegrable lattices applications are to be expected. The ultimate stability of driven aero machinery containing nonlinear periodic structures may be one example.Comment: 7 pages 7 figure

Sensing dynamic displacements in masonry rail bridges using 2D digital image correlation

Dynamic displacement measurements provide useful information for the assessment of masonry rail bridges, which constitute a significant part of the bridge stock in the UK and Europe. Commercial 2D Digital Image Correlation (DIC) techniques are well suited for this purpose. These systems provide precise non-contact displacement measurements simultaneously at many locations of the bridge with an easily configured camera setup. However, various sources of errors can affect the resolution, repeatability and accuracy of DIC field measurements. Typically, these errors are application specific and are not automatically corrected by commercial software. To address this limitation, this paper presents a survey of relevant DIC errors and discusses methods to minimise the influence of these errors during equipment setup and data processing. A case study application of DIC for multi-point displacement measurement of a masonry viaduct in Leeds is then described, where potential errors due to lighting changes, image texture and camera movements are minimised with an appropriate setup. Pixel-metric scaling errors are kept to a minimum with the use of a calibration method which utilises vanishing points in the image. However, comparisons of DIC relative displacement measurements to complementary strain measurements from the bridge demonstrate that other errors may have significant influence on the DIC measurement accuracy. Therefore the influence of measurement errors due to lens radial distortion and out of plane movements are quantified theoretically with pinhole camera and division distortion models. A method to correct for errors due to potential out of plane movements is then proposed

Dynamic response of a damaged masonry rail viaduct: Measurement and interpretation

Despite recent advances in modelling and testing techniques, assessing the serviceability of ageing masonry rail bridges remains a significant challenge. Most assessment methods are based on ultimate strength, while reliable measurement-based assessment criteria are lacking. This paper aims to improve the understanding of serviceability behaviour through detailed dynamic monitoring of the bridge locally (e.g. in locations of damage) and globally (e.g. interaction of different components). Quasi distributed sensing techniques (Fibre Bragg Grating cables and Digital Image Correlation) were used to quantify the bridge dynamic response through extensive measurement of strains and displacements. Specifically, these techniques were applied to two damaged spans of the Marsh Lane viaduct in Leeds, UK. A detailed investigation of the dynamic pier and arch barrel movements reveal how the response mechanisms relate to, and likely propagate, the existing damage. For instance, rotation of piers in the bridge longitudinal plane causes significant span opening and closing, which in turn causes the skewbacks and backing to rock on the piers. This is accompanied by flexural deformation of the arch, which forces the existing transverse cracks to experience high compressive strains. Similarly, the transverse rotation of piers due to the presence of the relieving arches causes spreading of the relieving arches and opening of the longitudinal crack above. These observations provide new insight into behaviour and lead to suggestions for improving assessment techniques for masonry viaducts

Greenhouse gas considerations in rail infrastructure in the UK

Transportation-related greenhouse gas (GHG) emissions account for an increasing proportion of total emissions in the UK and globally. The provision of rail transit is popularly proposed to reduce transport GHG emissions, but the provision of new infrastructure is itself GHG intensive. Understanding of the GHG emissions impact of rail projects is limited and very few longitudinal studies have been carried out. Existing assessments are often limited both in their scope and the factors considered. A holistic understanding of GHG impacts must include an assessment of capital GHG emissions, operational energy and maintenance as well as an assessment of ridership mode shift and mode share impacts and the relationship between transit infrastructure and land use. This paper explores rail infrastructure projects and their associated GHG emissions. Guidance is given on the aspects of rail planning, design and construction that must be considered to more fully understand the associated GHG impacts.The authors would like to thank The Commonwealth Scholarship Commission in the UK for the scholarship funding that facilitated this work