Search results for: structural heath monitoring (SHM)

Authors: Dacheng Li, Bo Huang, Qinjin Han, Ming Li

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Remotely sensed imagery with the high spatial and temporal characteristics, which it is hard to acquire under the current land observation satellites, has been considered as a key factor for monitoring environmental changes over both global and local scales. On a basis of the limited high spatial-resolution observations, challenged studies called spatiotemporal fusion have been developed for generating high spatiotemporal images through employing other auxiliary low spatial-resolution data while with high-frequency observations. However, a majority of spatiotemporal fusion approaches yield to satisfactory assumption, empirical but unstable parameters, low accuracy or inefficient performance. Although the spatiotemporal fusion methodology via sparse representation theory has advantage in capturing reflectance changes, stability and execution efficiency (even more efficient when overcomplete dictionaries have been pre-trained), the retrieval of high-accuracy dictionary and its response to fusion results are still pending issues. In this paper, we employ additional image pairs (here each image-pair includes a Landsat Operational Land Imager and a Moderate Resolution Imaging Spectroradiometer acquisitions covering the partial area of Baotou, China) only into the coupled dictionary training process based on K-SVD (K-means Singular Value Decomposition) algorithm, and attempt to improve the fusion results of two existing sparse representation based fusion models (respectively utilizing one and two available image-pair). The results show that more eligible image pairs are probably related to a more accurate overcomplete dictionary, which generally indicates a better image representation, and is then contribute to an effective fusion performance in case that the added image-pair has similar seasonal aspects and image spatial structure features to the original image-pair. It is, therefore, reasonable to construct multi-dictionary training pattern for generating a series of high spatial resolution images based on limited acquisitions.

Keywords: spatiotemporal fusion, sparse representation, K-SVD algorithm, dictionary learning

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Authors: A. Robak, M. Pieńko, E. Błazik-Borowa, J. Bęc, I. Szer

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The analyzes and classifications presented in the article were based on the research carried out in year 2016 and 2017 on a group of nearly one hundred scaffoldings assembled and used on construction sites in different parts of Poland. During scaffolding selection process efforts were made to maintain diversification in terms of parameters such as scaffolding size, investment size, type of investment, location and nature of conducted works. This resulted in the research being carried out on scaffoldings used for church renovation in a small town or attached to the facades of classic apartment blocks, as well as on scaffoldings used during construction of skyscrapers or facilities of the largest power plants. This variety allows to formulate general conclusions about the technical condition of used frame scaffoldings. Exploitation damages of the frame scaffolding elements were divided into three groups. The first group includes damages to the main structural components, which reduce the strength of the scaffolding elements and hence the whole structure. The qualitative analysis of these damages was made on the basis of numerical models that take into account the geometry of the damage and on the basis of computational nonlinear static analyzes. The second group focuses on exploitation damages such as the lack of a pin on the guardrail bolt which may cause an imminent threat to people using scaffolding. These are local damages that do not affect the bearing capacity and stability of the whole structure but are very important for safe use. The last group consider damages that reduce only aesthetic values and do not have direct impact on bearing capacity and safety of use. Apart from qualitative analyzes the article will present quantitative analyzes showing how frequently given type of damage occurs.

Keywords: scaffolding, damage, safety, numerical analysis

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Authors: Umberto Di Staso, Marco Soave, Alessio Giori, Federico Prandi, Raffaele De Amicis

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The increasing availability of information about earth surface elevation (Digital Elevation Models DEM) generated from different sources (remote sensing, Aerial Images, Lidar) poses the question about how to integrate and make available to the most than possible audience this huge amount of data. In order to exploit the potential of 3D elevation representation the quality of data management plays a fundamental role. Due to the high acquisition costs and the huge amount of generated data, highresolution terrain surveys tend to be small or medium sized and available on limited portion of earth. Here comes the need to merge large-scale height maps that typically are made available for free at worldwide level, with very specific high resolute datasets. One the other hand, the third dimension increases the user experience and the data representation quality, unlocking new possibilities in data analysis for civil protection, real estate, urban planning, environment monitoring, etc. The open-source 3D virtual globes, which are trending topics in Geovisual Analytics, aim at improving the visualization of geographical data provided by standard web services or with proprietary formats. Typically, 3D Virtual globes like do not offer an open-source tool that allows the generation of a terrain elevation data structure starting from heterogeneous-resolution terrain datasets. This paper describes a technological solution aimed to set up a so-called “Terrain Builder”. This tool is able to merge heterogeneous-resolution datasets, and to provide a multi-resolution worldwide terrain services fully compatible with CesiumJS and therefore accessible via web using traditional browser without any additional plug-in.

Keywords: Terrain Builder, WebGL, Virtual Globe, CesiumJS, Tiled Map Service, TMS, Height-Map, Regular Grid, Geovisual Analytics, DTM

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Authors: Bongsik Park, Jae Hyun Park, Jae-Yeol Cho

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Mixed structure, which is a kind of hybrid system, is incorporating steel beam and prestressed concrete beam. Hybrid bridge adopting mixed structure have some merits. Main span length can be made longer by using steel as main span material. In case of cable-stayed bridge having asymmetric span length, negative reaction at side span can be restrained without extra restraining devices by using weight difference between main span material and side span material. However angle of refraction might happen because of rigidity difference between materials and stress concentration also might happen because of abnormal loading transmission at joint in the hybrid bridge. Therefore the joint might be a weak point of the structural system and it needs to pay attention to design of the joint. However, design codes and standards about the joint in the hybrid-bridge have not been established so the joint designs in most of construction cases have been very conservative or followed previous design without extra verification. In this study parametric study using finite element analysis for optimal design of hybrid bridge joint is conducted. Before parametric study, finite element analysis was conducted based on previous experimental data and it is verified that analysis result approximated experimental data. Based on the finite element analysis results, parametric study was conducted. The parameters were selected as those have influences on joint behavior. Based on the parametric study results, optimal design of hybrid bridge joint has been determined.

Keywords: parametric study, optimal design, hybrid bridge, finite element analysis

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Authors: Sania Bashir

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A promising approach to healthcare delivery, telemedicine makes use of communication technology to reach out to remote regions of the world, allowing for beneficial interactions between diabetic patients and healthcare professionals as well as the provision of affordable and easily accessible medical care. The emergence of contemporary care models, fueled by the pervasiveness of mobile devices, provides better information, offers low cost with the best possible outcomes, and is known as digital health. It involves the integration of collected data using software and apps, as well as low-cost, high-quality outcomes. The goal of this study is to assess how well telemedicine works for diabetic patients and how it impacts their HbA1c levels. A questionnaire-based survey of 300 diabetics included 150 patients in each of the groups receiving usual care and via telemedicine. A descriptive and observational study that lasted from September 2021 to May 2022 was conducted. HbA1c has been gathered for both categories every three months. A remote monitoring tool has been used to assess the efficacy of telemedicine and continuing therapy instead of the customary three monthly meetings like in-person consultations. The patients were (42.3) 18.3 years old on average. 128 men were outnumbered by 172 women (57.3% of the total). 200 patients (66.6%) have type 2 diabetes, compared to over 100 (33.3%) candidates for type 1. Despite the average baseline BMI being within normal ranges at 23.4 kg/m², the mean baseline HbA1c (9.45 1.20) indicates that glycemic treatment is not well-controlled at the time of registration. While patients who use telemedicine experienced a mean percentage change of 10.5, those who visit the clinic experienced a mean percentage change of 3.9. Changes in HbA1c are dependent on several factors, including improvements in BMI (61%) after 9 months of research and compliance with healthy lifestyle recommendations for diet and activity. More compliance was achieved by the telemedicine group. It is an undeniable reality that patient-physician communication is crucial for enhancing health outcomes and avoiding long-term issues. Telemedicine has shown its value in the management of diabetes and holds promise as a novel technique for improved clinical-patient communication in the twenty-first century.

Keywords: diabetes, digital health, mobile app, telemedicine

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Authors: Laura E. Monroe

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As more non-native English-speaking students enroll in English-medium universities, even more faculty will instruct students who are unprepared for the rigors of post-secondary academic writing in English. Many faculty members lack training and knowledge regarding the assessment of non-native English-speaking students’ writing, as well as the ability to provide effective feedback. This quantitative study investigated the possible attitudinal factors, including demographics, which might affect faculty preparedness and grading practices for both native and non-native English-speaking students’ academic writing and plagiarism, as well as the reasons faculty do not deduct points from both populations’ writing errors. Structural equation modeling and SPSS Statistics were employed to analyze the results of a faculty questionnaire disseminated to individuals who had taught non-native English-speaking students in academic subject courses. The findings from this study illustrated that faculty’s native language, years taught, and institution type were significant factors in not deducting points for academic writing errors and plagiarism, and the major reasons for not deducting points for errors were that faculty had too many students to grade, not enough training in assessing student written errors and plagiarism and that the errors and plagiarism would have taken too long to explain. The practical implications gleaned from these results can be applied to most departments in English-medium post-secondary institutions regarding faculty preparedness and training in student academic writing errors and plagiarism, and recommendations for future research are given for similar types of preparation and guidance for post-secondary faculty, regardless of degree path or academic subject.

Keywords: assessment, faculty, non-native English-speaking students, writing

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Authors: Max Plotnikov, Arkadius Schier

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To counteract climate change, the European Commission adopted the European Green Deal (EDG) in 2019. Some of the main objectives of the EDG are climate neutrality by 2050, decarbonization, sustainable mobility, and the shift from a linear economy to a circular economy in the European Union. The mobility turnaround envisages, among other things, the switch from classic internal combustion vehicles to electromobility. The aforementioned goals are therefore accompanied by increased demand for lithium-ion batteries (LIBs) and the associated logistics. However, this inevitably gives rise to challenges that need to be addressed. Depending on whether the LIB is transported by road, rail, air, or sea, there are different regulatory frameworks in the European Union that relevant players in the value chain must adhere to. LIBs are classified as Dangerous Goods Class 9, and against this backdrop, there are various restrictions that need to be adhered to when transporting them for various actors. Currently, the exchange of information in the value chain between the various actors is almost entirely paper-based. Especially in the transport of dangerous goods, this often leads to a delay in the transport or to incorrect data. The exchange of information with the authorities is particularly essential in this context. A solution for the digital exchange of information is currently being developed. Electronic freight transport information (eFTI) enables fast and secure exchange of information between the players in the freight transport process. This concept is to be used within the supply chain from 2025. Another initiative that is expected to improve the monitoring of LIB in this context, among other things, is the battery pass. In July 2023, the latest battery regulation was adopted in the Official Journal of the European Union. This battery pass gives different actors static as well as dynamic information about the batteries depending on their access rights. This includes master data such as battery weight or battery category or information on the state of health or the number of negative events that the battery has experienced. The integration of the battery pass with the eFTI platform will be investigated for synergy effects in favor of the actors for battery transport.

Keywords: battery logistics, battery passport, data sharing, eFTI, sustainability

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Authors: Mahfoodh Saleh Al Sabbagh, Amitabh Mishra, Anwar Al Sheyadi

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A tremendous transformation is taking place in the state of education in Sultanate of Oman. The vision 2040 for Higher Education focuses on both academic and technical sides of education aims at improving the quality of education as per higher international standards with emphasis on learning and innovation, creativity and scientific research. The objective is to achieve a proficient education system that keeps abreast of the recent development, the essentials of sustainable development and enhancing the national identity. Higher Education Institutes have contributed immensely to the growth of education in Oman, in this context; Business Organization represents the most complex social structure known today due to its dynamic nature. Employees are considered as one of the dynamic resources of the organization and through their commitment and involvement organization becomes competitive. Organization Culture can be promoted to facilitate the achievement of job satisfaction and employees commitment. The purpose of the research is to explore the impact of Higher Educational Institutions Culture on employee satisfaction, and commitment. Based on primary data, the study was conducted in Higher Education Institutions in the Sultanate of Oman. Data was collected through questionnaire consisting of 60 questions related to culture, satisfaction, and commitment. The sample consisted of 330 employees of leading Higher Education Institutes in the Sultanate of Oman. Structural Equation Modeling was carried out on the data through SPSS and AMOS. Results indicate that culture of organization is significantly related with employees’ satisfaction and commitment both in direct and indirect ways. Significant theoretical and practical implications are driven from the outcomes of the study.

Keywords: organization culture, employee satisfaction and commitment, higher education, Sultanate of Oman

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Authors: Luis Guiliana, Andrea Osorio

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The lack of comprehension of the reservoir geomechanics conditions may cause operational problems that cost to the industry billions of dollars per year. The drilling operations at the Ceuta Field, Area 2 South, Maracaibo Lake, have been very expensive due to problems associated with drilling. The principal objective of this investigation is to develop a 3D geomechanical model in this area, in order to optimize the future drillings in the field. For this purpose, a 1D geomechanical model was built at first instance, following the workflow of the MEM (Mechanical Earth Model), this consists of the following steps: 1) Data auditing, 2) Analysis of drilling events and structural model, 3) Mechanical stratigraphy, 4) Overburden stress, 5) Pore pressure, 6) Rock mechanical properties, 7) Horizontal stresses, 8) Direction of the horizontal stresses, 9) Wellbore stability. The 3D MEM was developed through the geostatistic model of the Eocene C-SUP VLG-3676 reservoir and the 1D MEM. With this data the geomechanical grid was embedded. The analysis of the results threw, that the problems occurred in the wells that were examined were mainly due to wellbore stability issues. It was determined that the stress field change as the stratigraphic column deepens, it is normal to strike-slip at the Middle Miocene and Lower Miocene, and strike-slipe to reverse at the Eocene. In agreement to this, at the level of the Eocene, the most advantageous direction to drill is parallel to the maximum horizontal stress (157º). The 3D MEM allowed having a tridimensional visualization of the rock mechanical properties, stresses and operational windows (mud weight and pressures) variations. This will facilitate the optimization of the future drillings in the area, including those zones without any geomechanics information.

Keywords: geomechanics, MEM, drilling, stress

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Authors: Vijaykumar M. Baragi, Ramtilak Gattu, Gabriela Trifan, John L. Woodard, K. Meyers, Tim S. Halstead, Eric Hipple, Ewart Mark Haacke, Randall R. Benson

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NFL players, by virtue of their exposure to repetitive head injury, are at least twice as likely to develop Alzheimer's disease (AD) and dementia as the general population. Early recognition and intervention prior to onset of clinical symptoms could potentially avert/delay the long-term consequences of these diseases. Since AD is thought to have a long preclinical incubation period, the aim of the current research was to determine whether former NFL players, referred to a depression center, showed evidence of incipient dementia in their structural imaging prior to diagnosis of dementia. Thus, to identify neuroimaging markers of AD, against which former NFL players would be compared, we conducted a comprehensive volumetric analysis using a cohort of early stage AD patients (ADNI) to produce a set of brain regions demonstrating sensitivity to early AD pathology (i.e., the “AD fingerprint”). A cohort of 46 former NFL players’ brain MRIs were then interrogated using the AD fingerprint. Brain scans were done using a T1-weighted MPRAGE sequence. The Free Surfer image analysis suite (version 6.0) was used to obtain the volumetric and cortical thickness data. A total of 55 brain regions demonstrated significant atrophy or ex vacuo dilatation bilaterally in AD patients vs. healthy controls. Of the 46 former NFL players, 19 (41%) demonstrated a greater than expected number of atrophied/dilated AD regions when compared with age-matched controls, presumably reflecting AD pathology.

Keywords: alzheimers, neuroimaging biomarkers, traumatic brain injury, free surfer, ADNI

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Authors: Godwin Chigozie Okpara, Eugine Iheanacho

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The paper set out to assess the sustainability of debt in the Nigerian economy. Precisely, it sought to determine the level of debt sustainability and its impact on the growth of the economy; whether internationalization of capital market has positively influenced debt sustainability’s impact on economic growth; and to ascertain the direction of causality between external debt sustainability and the growth of GDP. In the light of these objectives, ratio analysis was employed for the determination of debt sustainability. Our findings revealed that the periods 1986 – 1994 and 1999 – 2004 were periods of severe unsustainable borrowing. The unit root test showed that the variables of the growth model were integrated of order one, I(1) and the cointegration test provided evidence for long run stability. Considering the dawn of internationalization of capital market, the researcher employed the structural break approach using Chow Breakpoint test on the vector error correction model (VECM). The result of VECM showed that debt sustainability, measured by debt to GDP ratio exerts negative and significant impact on the growth of the economy while debt burden measured by debt-export ratio and debt service export ratio are negative though insignificant on the growth of GDP. The Cho test result indicated that internationalization of capital market has no significant effect on the debt overhang impact on the growth of the Economy. The granger causality test indicates a feedback effect from economic growth to debt sustainability growth indicators. On the bases of these findings, the researchers made some necessary recommendations which if followed religiously will go a long way to ameliorating debt burdens and engendering economic growth.

Keywords: debt sustainability, internalization, capital market, cointegration, chow test

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Authors: Guanglin Song

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(Objective) Situated within the context of China's tiered medical treatment system, this study aims to analyze spatial causes of urban healthcare access difficulties from the perspective of the configuration of healthcare facilities. (Methods) A social network analysis approach is employed to construct a healthcare demand and supply flow network between major residential clusters and various tiers of hospitals in the city.(Conclusion) The findings reveal that:1.there exists overall maldistribution and over-concentration of healthcare resources in Study Area, characterized by structural imbalance; 2.the low rate of primary care utilization in Study Area is a key factor contributing to congestion at higher-tier hospitals, as excessive reliance on these institutions by neighboring communities exacerbates the problem; 3.gradual optimization of the healthcare facility layout in Study Area, encompassing holistic, local, and individual institutional levels, can enhance systemic efficiency and resource balance.(Prospects) This research proposes a method for evaluating urban healthcare resource distribution structures based on service flows within hierarchical networks. It offers spatially targeted optimization suggestions for promoting the implementation of the tiered healthcare system and alleviating challenges related to accessibility and congestion in seeking medical care. Provide some new ideas for researchers and healthcare managers in countries, cities, and healthcare management around the world with similar challenges.

Keywords: flow of public services, urban networks, healthcare facilities, spatial planning, urban networks

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Authors: Samim Khair Mohammad, Takeshi Tsuji, Chanmaly Chhun

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The Afghan Tajik (foreland) basin, located in the depression zone between mountain axes, is under compression and deformation during the collision of India with the Eurasian plate. The southern part of the Afghan Tajik basin in the Northern part of Afghanistan has not been well studied and explored, but considered for the significant potential for oil and gas resources. The Afghan Tajik basin depositional environments (< 8km) resulted from mixing terrestrial and marine systems, which has potential prospects of Jurrasic (deep) and Tertiary (shallow) petroleum systems. We used 2D regional seismic profiles with a total length of 674.8 km (or over an area of 2500 km²) in the southern part of the basin. To characterize hydrocarbon systems and structures in this study area, we applied advanced seismic attributes such as spectral decomposition (10 - 60Hz) based on time-frequency analysis with continuous wavelet transform. The spectral decomposition results yield the (averaging 20 - 30Hz group) spectral amplitude anomaly. Based on this anomaly result, seismic, and structural interpretation, the potential hydrocarbon accumulations were inferred around the main thrust folds in the tertiary (Paleogene+Neogene) petroleum systems, which appeared to be accumulated around the central study area. Furthermore, it seems that hydrocarbons dominantly migrated along the main thrusts and then concentrated around anticline fold systems which could be sealed by mudstone/carbonate rocks.

Keywords: The Afghan Tajik basin, seismic lines, spectral decomposition, thrust folds, hydrocarbon reservoirs

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Authors: Ncedo Cameron Xhala

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Several public sector institutions lack policy direction on how to successfully implement their large infrastructure investment projects. It is significant to improve strategic policy direction in public sector institutions in order to improve planning, management and implementation of large infrastructure investment projects. It is significant to improve an understanding of internal and external pressures that exerts pressure on large infrastructure projects. The significance is to fulfill the public sector’s mandate, align the sectors’ scarce resources, stakeholders and to improve project management processes. The study used a case study approach which was underpinned by a constructionist approach. The study used a theoretical sampling technique when selecting study participants, and was followed by a snowball sampling technique that was used to select an identified case study project purposefully. The study was qualitative in nature, collected and analyzed qualitative empirical data from the purposefully selected five subject matter experts and has analyzed the case study documents. The study used a semi-structured interview approach, analysed case study documents in a qualitative approach. The interviews were on a face-to-face basis and were guided by an interview guide with focused questions. The study used a three coding process step comprising of one to three steps when analysing the qualitative empirical data. Findings reveal that an improvement of strategic policy direction in public sector institutions improves the integration in planning, management and on implementation on large infrastructure investment projects. Findings show the importance of understanding the external and internal pressures when implementing public sector’s large infrastructure investment projects. The study concludes that strategic policy direction in public sector institutions results in improvement of planning, financing, delivery, monitoring and evaluation and successful implementation of the public sector’s large infrastructure investment projects.

Keywords: implementation, infrastructure, investment, management

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Authors: Robert G. Nini

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Soil consolidation is one of the biggest problem facing engineers. The consolidation process has an important role in settlement analysis for the embankments and footings resting on clayey soils. The settlement amount is related to the compression and the swelling indexes of the soil. Because the predominant upper soil layer in Lebanon is consisting mainly of clay, this layer is a real challenge for structural and highway engineering. To determine the effect of load and drainage on the engineering consolidation characteristics of Lebanese soil, a full experimental and synthesis study was conducted on different soil samples collected from many locations. This study consists of two parts. During the first part which is an experimental one, the Proctor test and the consolidation test were performed on the collected soil samples. After it, the identifications soil tests as hydrometer, specific gravity and Atterberg limits are done. The consolidation test which is the main test in this research is done by loading the soil for some days then an unloading cycle was applied. It takes two weeks to complete a typical consolidation test. Because of these reasons, during the second part of our research which is based on the analysis of the experiments results, some correlations were found between the main consolidation parameters as compression and swelling indexes with the other soil parameters easy to calculate. The results show that the compression and swelling indexes of Lebanese clays may be roughly estimated using a model involving one or two variables in the form of the natural void ratio and the Atterberg limits. These correlations have increasing importance for site engineers, and the proposed model also seems to be applicable to a wide range of clays worldwide.

Keywords: atterberg limits, clay, compression and swelling indexes, settlement, soil consolidation

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Authors: Jianguo Chen, Fenggang Zang, Yu Yang, Liangang Zheng

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Reactor Pressure Vessel (RPV) is an important security barrier in nuclear power plant. Crack like defects may be produced on RPV during the whole operation lifetime due to the harsh operation condition and irradiation embrittlement. During the severe loss of coolant accident, thermal shock happened as the injection of emergency cooling water into RPV, which results in re-pressurization of the vessel and very high tension stress on the vessel wall, this event called Pressurized Thermal Shock (PTS). Crack on the vessel wall may propagate even penetrate the vessel, so the safety of the RPV would undergo great challenge. Many assumptions in structure integrity evaluation make the result of deterministic fracture mechanics very conservative, which affect the operation lifetime of the plant. Actually, many parameters in the evaluation process, such as fracture toughness and nil-ductility transition temperature, have statistical distribution characteristics. So it is necessary to assess the structural integrity of RPV subjected to PTS event by means of Probabilistic Fracture Mechanics (PFM). Structure integrity evaluation methods of RPV subjected to PTS event are summarized firstly, then evaluation method based on probabilistic fracture mechanics are presented by considering the probabilistic characteristics of material and structure parameters. A comprehensive analysis example is carried out at last. The results show that the probability of crack penetrates through wall increases gradually with the growth of fast neutron irradiation flux. The results give advice for reactor life extension.

Keywords: fracture toughness, integrity evaluation, pressurized thermal shock, probabilistic fracture mechanics, reactor pressure vessel

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Authors: Adrien Pyskir, Manuel Collet, Zoran Dimitrijevic, Claude-Henri Lamarque

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During the last decades, great efforts have been made to reduce acoustic and vibrational disturbances in transportations, as it has become a key feature for comfort. Today, isolation and design have neutralized most of the troublesome vibrations, so that cars are quieter and more comfortable than ever. However, some problems remain unsolved, in particular concerning low-frequency isolation and the frequency-dependent stiffening of materials like rubber. To sum it up, a balance has to be found between a high static stiffness to sustain the vibration source’s mass, and low dynamic stiffness, as wideband as possible. Systems meeting these criteria are yet to be designed. We thus investigated solutions inspired by metamaterials to control efficiently low-frequency wave propagation. Structures exhibiting a negative Poisson ratio, also called auxetic structures, are known to influence the propagation of waves through beaming or damping. However, their stiffness can be quite peculiar as well, as they can present regions of zero stiffness on the stress-strain curve for compression. In addition, auxetic materials can be easily adapted in many ways, inducing great tuning potential. Using finite element software COMSOL Multiphysics, a resonant design has been tested through statics and dynamics simulations. These results are compared to experimental results. In particular, the bandgaps featured by these structures are analyzed as a function of design parameters. Great stiffness properties can be observed, including low-frequency dynamic stiffness loss and broadband transmission loss. Such features are very promising for practical isolation purpose, and we hope to adopt this kind of metamaterial into an effective industrial damper.

Keywords: auxetics, metamaterials, structural dynamics, vibration isolation

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Authors: V. Jelev, P. Petkov, P. Shindov

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Thin films of undoped and As-doped tin oxide (As:SnO2) were obtained on silicon and glass substrates at 450°- 480°C by spray pyrolysis technique. Tin chloride (SnCl4.5H2O) and As oxide (3As2O5.5H2O) were used as a source for Sn and As respectively. The As2O5 concentration was varied from 0 to 10 mol% in the starting water-alcoholic solution. The characterization of the films was provided with XRD, CEM, AFM and UV-VIS spectroscopy. The influence of the synthesis parameters (the temperature of the substrate, solution concentration, gas and solution flow rates, deposition time, nozzle-to substrate distance) on the optical, electrical and structural properties of the films was investigated. The substrate temperature influences on the surface topography, structure and resistivity of the films. Films grown at low temperatures (<300°C) are amorphous whereas this deposited at higher temperatures have certain degree of polycrystallinity. Thin oxide films deposited at 450°C are generally polycrystalline with tetragonal rutile structure. The resistivity decreases with dopant concentration. The minimum resistivity was achieved at dopant concentration about 2.5 mol% As2O5 in the solution. The transmittance greater than 80% and resistivity smaller than 7.5.10-4Ω.cm were achieved in the films deposited at 480°C. The As doped films (SnO2: As) deposited on silicon substrates was used for preparation of a large area position sensitive photodetector (PSD), acting on the base of a lateral photovoltaic effect. The position characteristic of PSD is symmetric to the zero and linear in the 80% of the active area. The SnO2 films are extremely stable under typical environmental conditions and extremely resistant to chemical etching.

Keywords: metal oxide film, SnO2 film, position sensitive photodetectors (PSD), lateral photovoltaic effect

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Authors: Xuewei Li, Jingfeng Yuan, Jianliang Zhou

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The 21st century has been called the century of human exploitation of underground space. Due to the characteristics of large quantity, tight schedule, low safety reserve and high uncertainty of deep foundation pit engineering, accidents frequently occur in deep foundation pit engineering, causing huge economic losses and casualties. With the successful application of information technology in the construction industry, building information modeling has become a research hotspot in the field of architectural engineering. Therefore, the application of building information modeling (BIM) and other information communication technologies (ICTs) in construction safety management is of great significance to improve the level of safety management. This research summed up the mechanism of the deep foundation pit engineering accident through the fault tree analysis to find the control factors of deep foundation pit engineering safety management, the deficiency existing in the traditional deep foundation pit construction site safety management. According to the accident cause mechanism and the specific process of deep foundation pit construction, the hazard information of deep foundation pit engineering construction site was identified, and the hazard list was obtained, including early warning information. After that, the system framework was constructed by analyzing the early warning information demand and early warning function demand of the safety management system of deep foundation pit. Finally, the safety management system of deep foundation pit construction site based on BIM through combing the database and Web-BIM technology was developed, so as to realize the three functions of real-time positioning of construction site personnel, automatic warning of entering a dangerous area, real-time monitoring of deep foundation pit structure deformation and automatic warning. This study can initially improve the current situation of safety management in the construction site of deep foundation pit. Additionally, the active control before the occurrence of deep foundation pit accidents and the whole process dynamic control in the construction process can be realized so as to prevent and control the occurrence of safety accidents in the construction of deep foundation pit engineering.

Keywords: Web-BIM, safety management, deep foundation pit, construction

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Authors: Massimo Tadi, M. Hadi Mohammad Zadeh, Ozge Ogut

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Although how cities’ forms are structured is studied, more efforts are needed on systemic comprehensions and evaluations of the urban morphology through quantitative metrics that are able to describe the performance of a city in relation to its formal properties. More research is required in this direction in order to better describe the urban form characteristics and their impact on the environmental performance of cities and to increase their sustainability stewardship. With the aim of developing a better understanding of the built environment’s systemic structure, the intention of this paper is to present a holistic methodology for studying the behavior of the built environment and investigate the methods for measuring the effect of urban structure to the environmental performance. This goal will be pursued through an inquiry into the morphological components of the urban systems and the complex relationships between them. Particularly, this paper focuses on proximity, referring to the proximity of different land-uses, is a concept with which Integrated Modification Methodology (IMM) explains how land-use allocation might affect the choice of mobility in neighborhoods, and especially, encourage or discourage non-motived mobility. This paper uses proximity to demonstrate that the structure attributes can quantifiably relate to the performing behavior in the city. The target is to devise a mathematical pattern from the structural elements and correlate it directly with urban performance indicators concerned with environmental sustainability. The paper presents some results of this rigorous investigation of urban proximity and its correlation with performance indicators in four different areas in the city of Milan, each of them characterized by different morphological features.

Keywords: built environment, ecology, sustainable indicators, sustainability, urban morphology

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Authors: S. Mokhtar, R. Ibrahim, K. Abdan, A. Rashidi

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The population in the world are growing in very fast rate. It is expected that urban growth and development would create serious questions of food production and processing, transport, and consumption. Future smart green city policies are emerging to support new ways of visualizing, organizing and managing the city and its flows towards developing more sustainable cities in ensuring food security while maintaining its biodiversity. This is a survey paper analyzing the feasibility of developing a smart vertical farming system for climbing food plant to meet the need of food consumption in urban cities with an alternative green material. This paper documents our investigation on specific requirement for farming high valued climbing type food plant suitable for vertical farming, development of appropriate biocomposite material composition, and design recommendations for developing a new smart vertical farming system inside urban buildings. Results include determination of suitable specific climbing food plant species and material manufacturing processes for reinforcing natural fiber for biocomposite material. The results are expected to become recommendations for developing alternative structural materials for climbing food plant later on towards the development of the future smart vertical farming system. This paper contributes to supporting urban farming in cities and promotes green materials for preserving the environment. Hence supporting efforts in food security agenda especially for developing nations.

Keywords: biocomposite, natural reinforce fiber, smart farming, vertical farming

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Authors: Hyo-Min Kim, Seokjin Ham, Mi-Joung Yoo, Minseon Kim, Tae-Young Roh

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The gastrointestinal (GI) tract of most animals, including murine, is highly compartmentalized epithelia which also provide distinct different functions of its own tissue. Nevertheless, these epithelia share certain characteristics that enhance immune responses to infections and maintain the barrier function of the intestine. GI tract epithelia also undergo regeneration not only in homeostatic conditions but also in a response to the damage. A full turnover of the murine gastrointestinal epithelium occurs every 4-5 day, a process that is regulated and maintained by a minor population of Lgr5+ adult stem cell that commonly conserved in the bottom of crypts through GI tract. Maintenance of the stem cell is somehow regulated by epigenetic factors according to recent studies. Chromatin vacancy, remodelers, histone variants and histone modifiers could affect adult stem cell fate. In this study, Lgr5-EGFP reporter mouse was used to take advantage of exploring the epigenetic dynamics among Lgr5 positive mutual stem cell in GI tract. Cells were isolated by fluorescence-activated cell sorting (FACS), gene expression levels, chromatin accessibility changes and histone modifications were analyzed. Some notable chromatin structural related epigenetic variants were detected. To identify the overall cell-cell interaction inside the stem cell niche, an extensive genome-wide analysis should be also followed. According to the results, nevertheless, we expected a broader understanding of cellular niche maintaining stem cells and epigenetic barriers through conserved stem cell in GI tract. We expect that our study could provide more evidence of adult stem cell plasticity and more chances to understand each stem cell that takes parts in certain organs.

Keywords: adult stem cell, epigenetics, LGR5 stem cell, gastrointestinal tract

Procedia PDF Downloads 211

Authors: Naijin Wu, Peizhong Li, Haijian Wang, Wenxia Wei, Yun Song

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Chlorinated aliphatic hydrocarbons (CAHs) pollution poses a severe threat to human health and is persistent in groundwater. Although chemical reduction or bioremediation is effective, it is still hard to achieve their complete and rapid dechlorination. Recently, the combination of zero-valent iron and biostimulation has been considered to be one of the most promising strategies, but field studies of this technology are scarce. In a typical site contaminated by various types of CAHs, basic physicochemical parameters of groundwater, CAHs and their product concentrations, and microbial abundance and diversity were monitored after a remediation slurry containing both micron zero-valent iron (mZVI) and biostimulation components were directly injected into the aquifer. Results showed that groundwater could form and keep low oxidation-reduction potential (ORP), a neutral pH, and anoxic conditions after different degrees of fluctuations, which was benefit for the reductive dechlorination of CAHs. The injection also caused an obvious increase in the total organic carbon (TOC) concentration and sulfate reduction. After 253 days post-injection, the mean concentration of total chlorinated ethylene (CEE) from two monitoring wells decreased from 304 μg/L to 8 μg/L, and total chlorinated ethane (CEA) decreased from 548 μg/L to 108 μg/L. Occurrence of chloroethane (CA) suggested that hydrogenolysis dechlorination was one of the main degradation pathways for CEA, and also hints that biological dechlorination was activated. A significant increase of ethylene at day 67 post-injection indicated that dechlorination was complete. Additionally, the total bacterial counts increased by 2-3 orders of magnitude after 253 days post-injection. And the microbial species richness decreased and gradually changed to anaerobic/fermentative bacteria. The relative abundance of potential degradation bacteria increased corresponding to the degradation of CAHs. This work demonstrates that mZVI and biostimulation can be combined to achieve the efficient removal of various CAHs from contaminated groundwater sources.

Keywords: chlorinated aliphatic hydrocarbons, groundwater, field study, zero-valent iron, biostimulation

Procedia PDF Downloads 143

Authors: Suliman Al Balawi

Abstract:

Food waste is a significant problem in the Kingdom of Saudi Arabia (KSA). About SR13 billion worth of food is wasted per year in the KSA. From moral, social, and economic perspectives, it is essential to reduce the wastage of food. Although studies have identified the amount of food waste in the KSA, there is a lack of research on why people in the KSA waste food; thus, it is difficult to design efficient intervention programs to reduce food waste. This research investigates the key factors that influence the food waste behavior of the people of the KSA. A food waste behavior model is proposed in this study that has moral disengagement at the center of the model. Following a literature survey, it is hypothesised that religiosity, hedonic value, frugality, and trait cynicism are the antecedents of moral disengagement that are likely to impact the food waste behavior of the people of the KSA. The study further posits that an intervention strategy in the form of a social marketing campaign that focuses on lowering the level of moral disengagement could reduce the food waste behavior of the people of the KSA. This study will apply a pre-test/post-test experimental design (control group). A random sampling method will be used to select participants from the (employees of a chosen firm) in the KSA. The social marketing campaign will be run for six months through the Corporate Social Responsibility Department of the Company, and to analyse the experimental data, structural equation modeling (SEM) will be used. The outcomes of the study will demonstrate the effectiveness of a social marketing campaign for improving the food waste behavior of the people of the KSA and will ultimately lay the foundation for designing efficient intervention programs in the future. This study will contribute to the knowledge on food waste behavior by testing a newly proposed food waste behavior model in the KSA.

Keywords: food waste, social marketing, Saudi Arabia, moral disengagement

Procedia PDF Downloads 159

Authors: Masoumeh Haghbin Nazarpak, Hamidreza Tolabi, Aryan Ekhlasi

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Bone defects are mentioned as one of the most challenging clinical conditions, affecting millions of people each year. A fracture, osteoporosis, tumor, or infection usually causes these defects. At present, autologous and allogeneic grafts are used to correct bone defects, but these grafts have some difficulties, such as limited access, infection, disease transmission, and immune rejection. Bone tissue engineering is considered a new strategy for repairing bone defects. However, problems with scaffolds’ design with unique structures limit their clinical applications. In addition, numerous in-vitro studies have been performed on the behavior of bone cells in two-dimensional environments. Still, cells grow in physiological situations in the human body in a three-dimensional environment. As a result, the controlled design of porous structures with high structural complexity and providing the necessary flexibility to meet specific needs in bone tissue repair is beneficial. For this purpose, a three-dimensional composite scaffold based on gelatin and sodium alginate hydrogels is used in this research. In addition, the antibacterial drug-loaded halloysite nanotubes were introduced into the hydrogel scaffold structure to provide a suitable substrate for controlled drug release. The presence of halloysite nanotubes improved hydrogel’s properties, while the drug eliminated infection and disease transmission. Finally, it can be acknowledged that the composite scaffold prepared in this study for bone tissue engineering seems promising.

Keywords: halloysite nanotubes, bone tissue engineering, composite scaffold, controlled drug release

Procedia PDF Downloads 46

Authors: Jefto Terzovic, Ana Kontic, Isidora Ilic

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In the proposed design concept, laminated glass and laminated plexiglass, as ”unconventional materials”, are considered as a filling in a steel frame on which they overlap by the intermediate rubber layer, thereby forming a composite assembly. In this way vertical elements of stiffening are formed, capable for reception of seismic force and integrated into the structural system of the building. The applicability of such a system was verified by experiments in laboratory conditions where the experimental models based on laminated glass and laminated plexiglass had been exposed to the cyclic loads that simulate the seismic force. In this way the load capacity of composite assemblies was tested for the effects of dynamic load that was parallel to assembly plane. Thus, the stress intensity to which composite systems might be exposed was determined as well as the range of the structure stiffening referring to the expressed deformation along with the advantages of a particular type of filling compared to the other one. Using specialized software whose operation is based on the finite element method, a computer model of the structure was created and processed in the case study; the same computer model was used for analyzing the problem in the first phase of the design process. The stiffening system based on composite assemblies tested in laboratories is implemented in the computer model. The results of the modal analysis and seismic calculation from the computer model with stiffeners applied showed an efficacy of such a solution, thus rounding the design procedures for aseismic stiffening by using unconventional materials.

Keywords: laminated glass, laminated plexiglass, aseismic stiffening, experiment, laboratory testing, computer model, finite element method

Procedia PDF Downloads 62

Authors: Jessica Pinheiro Silva, Brenda Rabello De Camargo, Daniel Gusmao De Morais, Eliane Ferreira Noronha

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The utilization of lignocellulosic biomass as source of polysaccharides for industrial applications requires an arsenal of enzymes with different mode of action able to hydrolyze its complex and recalcitrant structure. Clostridium thermocellum is gram-positive, thermophilic bacterium producing lignocellulosic hydrolyzing enzymes in the form of multi-enzyme complex, termed celulossomes. This complex has several hydrolytic enzymes attached to a large and enzymically inactive protein known as Cellulosome-integrating protein (CipA), which serves as a scaffolding protein for the complex produced. This attachment occurs through specific interactions between cohesin modules of CipA and dockerin modules in enzymes. The present work aims to construct celulosomes in vitro with the structural protein CipA, a xylanase called Xyn10D and a cellulose called CelJ from C.thermocellum. A mini-scafoldin was constructed from modules derived from CipA containing two cohesion modules. This was cloned and expressed in Escherichia coli. The other two genes were cloned under the control of the alcohol oxidase 1 promoter (AOX1) in the vector pPIC9 and integrated into the genome of the methylotrophic yeast Pichia pastoris GS115. Purification of each protein is being carried out. Further studies regarding enzymatic activity of the cellulosome is going to be evaluated. The cellulosome built in vitro and composed of mini-CipA, CelJ and Xyn10D, can be very interesting for application in industrial processes involving the degradation of plant biomass.

Keywords: cellulosome, CipA, Clostridium thermocellum, cohesin, dockerin, yeast

Procedia PDF Downloads 214

Authors: Jeroen De Ceuster

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This study is the first empirical analysis of the link between corporate governance and European Union competition law. Although competition law enforcement is often studied through the lens of competition law, we offer an alternative perspective by looking at a number of corporate governance factor at the level of the board of directors. We find that undertakings where the Chief Executive Officer is also chairman of the board are twice as likely to violate European Union competition law. No significant relationship was found between European Union competition law infringements and gender diversity of the board, the size of the board, the percentage of directors appointed after the Chief Executive Officer, the percentage of independent directors, or the presence of corporate social responsibility (CSR) committee. This contribution is based on a 1-1 matched peer study. Our sample includes all ultimate parent companies with a board that have been sanctioned by the European Commission for either anticompetitive agreements or abuse of dominance for the period from 2004 to 2018. These companies were matched to a company with headquarters in the same country, belongs to the same industry group, is active in the European Economic Area, and is the nearest neighbor to the infringing company in terms of revenue. Our final sample includes 121 pairs. As is common with matched peer studies, we use CLR to analyze the differences within these pairs. The only statistically significant independent variable after controlling for size and performance is CEO/Chair duality. The results indicate that companies whose Chief Executive Officer also functions as chairman of the board are twice as likely to infringe European Union competition law. This is in line with the monitoring theory of the board of directors, which states that its primary function is to monitor top management. Since competition law infringements are mostly organized by management and hidden from board directors, the results suggest that a Chief Executive Officer who is also chairman is more likely to be either complicit in the infringement or less critical towards his day-to-day colleagues and thus impedes proper detection by the board of competition law infringements.

Keywords: corporate governance, competition law, board of directors, board independence, ender diversity, corporate social responisbility

Procedia PDF Downloads 110

Authors: Suwapitch Chalongkulasak, Teerasak E-Kobon, Pramote Chumnanpuen

Abstract:

Acne vulgaris is a common skin disease mainly caused by the Gram–positive pathogenic bacterium, Propionibacterium acnes. This bacterium stimulates inflammation process in human sebaceous glands. Giant African snail (Achatina fulica) is alien species that rapidly reproduces and seriously damages agricultural products in Thailand. There were several research reports on the medical and pharmaceutical benefits of this snail mucus peptides and proteins. This study aimed to in silico predict multifunctional bioactive peptides from A. fulica mucus peptidome using several bioinformatic tools for determination of antimicrobial (iAMPpred), anti–biofilm (dPABBs), cytotoxic (Toxinpred), cell membrane penetrating (CPPpred) and anti–quorum sensing (QSPpred) peptides. Three candidate peptides with the highest predictive score were selected and re-designed/modified to improve the required activities. Structural and physicochemical properties of six anti–P. acnes (APA) peptide candidates were performed by PEP–FOLD3 program and the five aforementioned tools. All candidates had random coiled structure and were named as APA1–ori, APA2–ori, APA3–ori, APA1–mod, APA2–mod and APA3–mod. To validate the APA activity, these peptide candidates were synthesized and tested against six isolates of P. acnes. The modified APA peptides showed high APA activity on some isolates. Therefore, our biomimetic mucus peptides could be useful for preventing acne vulgaris and further examined on other activities important to medical and pharmaceutical applications.

Keywords: Propionibacterium acnes, Achatina fulica, peptidomes, antibacterial peptides, snail mucus

Procedia PDF Downloads 115

Authors: Ferhat Erdal, Osman Tunca, Serkan Tas, Serdar Carbas

Abstract:

Web-expanded steel beams provide an easy and economical solution for the systems having longer structural members. The main goal of manufacturing these beams is to increase the moment of inertia and section modulus, which results in greater strength and rigidity. Until recently, there were two common types of open web-expanded beams: with hexagonal openings, also called castellated beams, and beams with circular openings referred to as cellular beams, until the generation of sinusoidal web-expanded beams. In the present research, the optimum design of a new generation beams, namely sinusoidal web-expanded beams, will be carried out and the design results will be compared with castellated and cellular beam solutions. Thanks to a reduced fabrication process and substantial material savings, the web-expanded beam with sinusoidal holes (Angelina™ Beam) meets the economic requirements of steel design problems while ensuring optimum safety. The objective of this research is to carry out non-linear finite element analysis (FEA) of the web-expanded beam with sinusoidal holes. The FE method has been used to predict their entire response to increasing values of external loading until they lose their load carrying capacity. FE model of each specimen that is utilized in the experimental studies is carried out. These models are used to simulate the experimental work to verify of test results and to investigate the non-linear behavior of failure modes such as web-post buckling, shear buckling and vierendeel bending of beams.

Keywords: steel structures, web-expanded beams, angelina beam, optimum design, failure modes, finite element analysis

Procedia PDF Downloads 261