Search results for: nuclear fuel cycle
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4275

Search results for: nuclear fuel cycle

1185 Acanthopanax koreanum and Major Ingredient, Impressic Acid, Possess Matrix Metalloproteinase-13 Down-Regulating Capacity and Protect Cartilage Destruction

Authors: Hyun Lim, Dong Sook Min, Han Eul Yun, Kil Tae Kim, Ya Nan Sun, Young Ho Kim, Hyun Pyo Kim

Abstract:

Matrix metalloproteinase (MMP)-13 has an important role for degrading cartilage materials under inflammatory conditions such as arthritis. Since the 70% ethanol extract of Acanthopanax koreanum inhibited MMP-13 expression in IL-1β-treated human chondrocyte cell line, SW1353, two major constituents including acanthoic acid and impressic acid were initially isolated from the same plant materials and their MMP-13 down-regulating capacity was examined. In IL-1β-treated SW1353 cells, acanthoic acid and impressic acid significantly and concentration-dependently inhibited MMP-13 expression at 10 – 100 μM and 0.5 – 10 μM, respectively. The potent one, impressic acid, was found to inhibit MMP-13 expression by blocking the phosphorylation of signal transducer and activator of transcription-1/-2 (STAT-1/-2) and activation of c-Jun and c-Fos among cellular signaling pathway involved, but did not affect the activation of mitogen-activated protein kinases (MAPKs) and nuclear transcription factor-κB (NF-κB). Further, impressic acid was also found to inhibit the expression of MMP-13 mRNA (47.7% inhibition at 10 μM), the glycosaminoglycan release (42.2% reduction at 10 μM) and proteoglycan loss in IL-1-treated rabbit cartilage explants culture. For a further study, 21 impressic acid derivatives were isolated from the same plant materials and their suppressive activities against MMP-13 expression were examined. Among the derivatives, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F and acantrifoside A clearly down-regulated MMP-13 expression, but impressic acid being most potent. All these results suggest that impressic acid, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F, acantrifoside A and A. koreanum may have a potential for therapeutic agents to prevent cartilage degradation possibly by inhibiting matrix protein degradation.

Keywords: acanthoic acid, Acanthopanax koreanum, cartilage, impressic acid, matrix metalloproteinase

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1184 CO₂ Absorption Studies Using Amine Solvents with Fourier Transform Infrared Analysis

Authors: Avoseh Funmilola, Osman Khalid, Wayne Nelson, Paramespri Naidoo, Deresh Ramjugernath

Abstract:

The increasing global atmospheric temperature is of great concern and this has led to the development of technologies to reduce the emission of greenhouse gases into the atmosphere. Flue gas emissions from fossil fuel combustion are major sources of greenhouse gases. One of the ways to reduce the emission of CO₂ from flue gases is by post combustion capture process and this can be done by absorbing the gas into suitable chemical solvents before emitting the gas into the atmosphere. Alkanolamines are promising solvents for this capture process. Vapour liquid equilibrium of CO₂-alkanolamine systems is often represented by CO₂ loading and partial pressure of CO₂ without considering the liquid phase. The liquid phase of this system is a complex one comprising of 9 species. Online analysis of the process is important to monitor the concentrations of the liquid phase reacting and product species. Liquid phase analysis of CO₂-diethanolamine (DEA) solution was performed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. A robust Calibration was performed for the CO₂-aqueous DEA system prior to an online monitoring experiment. The partial least square regression method was used for the analysis of the calibration spectra obtained. The models obtained were used for prediction of DEA and CO₂ concentrations in the online monitoring experiment. The experiment was performed with a newly built recirculating experimental set up in the laboratory. The set up consist of a 750 ml equilibrium cell and ATR-FTIR liquid flow cell. Measurements were performed at 400°C. The results obtained indicated that the FTIR spectroscopy combined with Partial least square method is an effective tool for online monitoring of speciation.

Keywords: ATR-FTIR, CO₂ capture, online analysis, PLS regression

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1183 A Techno-Economic Simulation Model to Reveal the Relevance of Construction Process Impact Factors for External Thermal Insulation Composite System (ETICS)

Authors: Virgo Sulakatko

Abstract:

The reduction of energy consumption of the built environment has been one of the topics tackled by European Commission during the last decade. Increased energy efficiency requirements have increased the renovation rate of apartment buildings covered with External Thermal Insulation Composite System (ETICS). Due to fast and optimized application process, a large extent of quality assurance is depending on the specific activities of artisans and are often not controlled. The on-site degradation factors (DF) have the technical influence to the façade and cause future costs to the owner. Besides the thermal conductivity, the building envelope needs to ensure the mechanical resistance and stability, fire-, noise-, corrosion and weather protection, and long-term durability. As the shortcomings of the construction phase become problematic after some years, the common value of the renovation is reduced. Previous work on the subject has identified and rated the relevance of DF to the technical requirements and developed a method to reveal the economic value of repair works. The future costs can be traded off to increased the quality assurance during the construction process. The proposed framework is describing the joint simulation of the technical importance and economic value of the on-site DFs of ETICS. The model is providing new knowledge to improve the resource allocation during the construction process by enabling to identify and diminish the most relevant degradation factors and increase economic value to the owner.

Keywords: ETICS, construction technology, construction management, life cycle costing

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1182 Circadian Expression of MicroRNAs in Colon and Its Changes during Colorectal Tumorigenesis

Authors: Katerina Balounova, Jiri Pacha, Peter Ergang, Martin Vodicka, Pavlina Kvapilova

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MicroRNAs are small non-coding RNAs involved in a wide range of physiological processes. Post-transcriptional regulation of gene expression by microRNAs gives the organism a further level of control of the gene-expression program and the disruption of this microRNA regulatory mechanism seems to increase the risk of various pathophysiological conditions including tumorigenesis. To the present day, microRNAs were shown to participate in the mayor signalization pathways leading to tumorigenesis, including proliferation, cell cycle, apoptosis and metastasis formation. In addition, microRNAs have been found to play important roles in the generation and maintenance of circadian clock. These clocks generate circadian rhythms, which participate in a number of regulatory pathways. Disruption of the circadian signals seems to be associated with the development and the progression of tumours including colorectal cancer. We investigated therefore whether the diurnal profiles of miRNAs linked to tumorigenesis and regulation of circadian clock are changed during tumorigenesis. Based on published data we chose 10 microRNAs linked to tumorigenesis or circadian clock (let-7b-5p, miR 1 3p, miR 106b 5p, miR 141 3p, miR 191 5p, miR 20a 5p, miR 25 3p, miR 29a 3p, miR 34a 5p and miR 93 5p) and compared their 24-hr expression profiles in healthy and in chemically induces primary colorectal tumours of 52week-old mice. Using RT-qPCR we proved circadian rhythmicity in let-7b-5p, miR 106b 5p, miR 141 3p, miR 191 5p, miR 20a 5p, miR 25 3p, miR 29a 3p and miR 93 5p in healthy colon but not in tumours. The acrophases of miR 106b 5p, miR 141 3p, miR 191 5p, miR 20a 5p, miR 25 3p and miR 93 5p were reached around CT 24, the acrophases of let-7b-5p and miR-29a-3p were slightly shifted and reached around CT 21. In summary, our results show that circadian regulation of some colonic microRNAs is greatly affected by neoplastic transformation.

Keywords: circadian rhythm, colon, colorectal cancer, microRNA, tumorigenesis

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1181 Optimal Sequential Scheduling of Imperfect Maintenance Last Policy for a System Subject to Shocks

Authors: Yen-Luan Chen

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Maintenance has a great impact on the capacity of production and on the quality of the products, and therefore, it deserves continuous improvement. Maintenance procedure done before a failure is called preventive maintenance (PM). Sequential PM, which specifies that a system should be maintained at a sequence of intervals with unequal lengths, is one of the commonly used PM policies. This article proposes a generalized sequential PM policy for a system subject to shocks with imperfect maintenance and random working time. The shocks arrive according to a non-homogeneous Poisson process (NHPP) with varied intensity function in each maintenance interval. As a shock occurs, the system suffers two types of failures with number-dependent probabilities: type-I (minor) failure, which is rectified by a minimal repair, and type-II (catastrophic) failure, which is removed by a corrective maintenance (CM). The imperfect maintenance is carried out to improve the system failure characteristic due to the altered shock process. The sequential preventive maintenance-last (PML) policy is defined as that the system is maintained before any CM occurs at a planned time Ti or at the completion of a working time in the i-th maintenance interval, whichever occurs last. At the N-th maintenance, the system is replaced rather than maintained. This article first takes up the sequential PML policy with random working time and imperfect maintenance in reliability engineering. The optimal preventive maintenance schedule that minimizes the mean cost rate of a replacement cycle is derived analytically and determined in terms of its existence and uniqueness. The proposed models provide a general framework for analyzing the maintenance policies in reliability theory.

Keywords: optimization, preventive maintenance, random working time, minimal repair, replacement, reliability

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1180 Bluetooth Communication Protocol Study for Multi-Sensor Applications

Authors: Joao Garretto, R. J. Yarwood, Vamsi Borra, Frank Li

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Bluetooth Low Energy (BLE) has emerged as one of the main wireless communication technologies used in low-power electronics, such as wearables, beacons, and Internet of Things (IoT) devices. BLE’s energy efficiency characteristic, smart mobiles interoperability, and Over the Air (OTA) capabilities are essential features for ultralow-power devices, which are usually designed with size and cost constraints. Most current research regarding the power analysis of BLE devices focuses on the theoretical aspects of the advertising and scanning cycles, with most results being presented in the form of mathematical models and computer software simulations. Such computer modeling and simulations are important for the comprehension of the technology, but hardware measurement is essential for the understanding of how BLE devices behave in real operation. In addition, recent literature focuses mostly on the BLE technology, leaving possible applications and its analysis out of scope. In this paper, a coin cell battery-powered BLE Data Acquisition Device, with a 4-in-1 sensor and one accelerometer, is proposed and evaluated with respect to its Power Consumption. First, evaluations of the device in advertising mode with the sensors turned off completely, followed by the power analysis when each of the sensors is individually turned on and data is being transmitted, and concluding with the power consumption evaluation when both sensors are on and respectively broadcasting the data to a mobile phone. The results presented in this paper are real-time measurements of the electrical current consumption of the BLE device, where the energy levels that are demonstrated are matched to the BLE behavior and sensor activity.

Keywords: bluetooth low energy, power analysis, BLE advertising cycle, wireless sensor node

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1179 Early-Stage Venture Investment Model: Evidence from Saudi Arabia

Authors: Tibah Alharbi, Renzo Cordina, David Power

Abstract:

Relatively few studies have explored how venture capitalist investors (VCs) make investment decisions and the information they rely on when taking an equity stake in an investee company. In addition, little is known about how much investors monitor start-ups after the decision to invest has been made. The VC scene in the US or European context is understood better than that of developing countries such as those in the Middle East. Although some differences among VC investors have been identified, the reasons behind such differences have not been fully explored – especially in a country such as Saudi Arabia. Therefore, this research seeks to understand the impact of external factors on the VC investor’ behaviour. The unique cultural and legal environments in the Kingdom of Saudi Arabia, the growing VC sector in the country, and the increasing importance attached to start-ups under the Saudi Government’s Vision 2030 program make such an investigation timely. Ascertaining the perceptions of VC investors in such a context will provide a deeper understanding of the determinants of VC investment in a novel setting. Using semi-structured interviews with over 20 participants, the research explores the structure of VC funds, the cycle of the VC investment in a start-up from the sourcing of deals, the screening and evaluation of such deals, the closing of such deals, and finally, the monitoring of such investments before the decision to exit such deals at the appropriate time. The results show some similarities to the VC model, which characterizes such investment in the US and Europe, but several differences emerge given the unique cultural and legal settings within the Kingdom. The results provide an in-depth understanding of the VC investors’ mindset relative to the existing studies in the literature.

Keywords: exit, monitoring, start-ups, venture capital

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1178 Microbial Electrochemical Remediation System: Integrating Wastewater Treatment with Simultaneous Power Generation

Authors: Monika Sogani, Zainab Syed, Adrian C. Fisher

Abstract:

Pollution of estrogenic compounds has caught the attention of researchers as the slight increase of estrogens in the water bodies has a significant impact on the aquatic system. They belong to a class of endocrine disrupting compounds (EDCs) and are able to mimic hormones or interfere with the action of endogenous hormones. The microbial electrochemical remediation system (MERS) is employed here for exploiting an electrophototrophic bacterium for evaluating the capacity of biodegradation of ethinylestradiol hormone (EE2) under anaerobic conditions with power generation. MERS using electro-phototrophic bacterium offers a tailored solution of wastewater treatment in a developing country like India which has a huge solar potential. It is a clean energy generating technology as they require only sunlight, water, nutrients, and carbon dioxide to operate. Its main feature that makes it superior over other technologies is that the main fuel for this MERS is sunlight which is indefinitely present. When grown in light with organic compounds, these photosynthetic bacteria generate ATP by cyclic photophosphorylation and use carbon compounds to make cell biomass (photoheterotrophic growth). These cells showed EE2 degradation and were able to generate hydrogen as part of the process of nitrogen fixation. The two designs of MERS were studied, and a maximum of 88.45% decrease in EE2 was seen in a total period of 14 days in the better design. This research provides a better insight into microbial electricity generation and self-sustaining wastewater treatment facilities. Such new models of waste treatment aiming waste to energy generation needs to be followed and implemented for building a resource efficient and sustainable economy.

Keywords: endocrine disrupting compounds, ethinylestradiol, microbial electrochemical remediation systems, wastewater treatment

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1177 Comparison of FNTD and OSLD Detectors' Responses to Light Ion Beams Using Monte Carlo Simulations and Exprimental Data

Authors: M. R. Akbari, H. Yousefnia, A. Ghasemi

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Al2O3:C,Mg fluorescent nuclear track detector (FNTD) and Al2O3:C optically stimulated luminescence detector (OSLD) are becoming two of the applied detectors in ion dosimetry. Therefore, the response of these detectors to hadron beams is highly of interest in radiation therapy (RT) using ion beams. In this study, these detectors' responses to proton and Helium-4 ion beams were compared using Monte Carlo simulations. The calculated data for proton beams were compared with Markus ionization chamber (IC) measurement (in water phantom) from M.D. Anderson proton therapy center. Monte Carlo simulations were performed via the FLUKA code (version 2011.2-17). The detectors were modeled in cylindrical shape at various depths of the water phantom without shading each other for obtaining relative depth dose in the phantom. Mono-energetic parallel ion beams in different incident energies (100 MeV/n to 250 MeV/n) were collided perpendicularly on the phantom surface. For proton beams, the results showed that the simulated detectors have over response relative to IC measurements in water phantom. In all cases, there were good agreements between simulated ion ranges in the water with calculated and experimental results reported by the literature. For proton, maximum peak to entrance dose ratio in the simulated water phantom was 4.3 compared with about 3 obtained from IC measurements. For He-4 ion beams, maximum peak to entrance ratio calculated by both detectors was less than 3.6 in all energies. Generally, it can be said that FLUKA is a good tool to calculate Al2O3:C,Mg FNTD and Al2O3:C OSLD detectors responses to therapeutic proton and He-4 ion beams. It can also calculate proton and He-4 ion ranges with a reasonable accuracy.

Keywords: comparison, FNTD and OSLD detectors response, light ion beams, Monte Carlo simulations

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1176 Mathematical Modelling and AI-Based Degradation Analysis of the Second-Life Lithium-Ion Battery Packs for Stationary Applications

Authors: Farhad Salek, Shahaboddin Resalati

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The production of electric vehicles (EVs) featuring lithium-ion battery technology has substantially escalated over the past decade, demonstrating a steady and persistent upward trajectory. The imminent retirement of electric vehicle (EV) batteries after approximately eight years underscores the critical need for their redirection towards recycling, a task complicated by the current inadequacy of recycling infrastructures globally. A potential solution for such concerns involves extending the operational lifespan of electric vehicle (EV) batteries through their utilization in stationary energy storage systems during secondary applications. Such adoptions, however, require addressing the safety concerns associated with batteries’ knee points and thermal runaways. This paper develops an accurate mathematical model representative of the second-life battery packs from a cell-to-pack scale using an equivalent circuit model (ECM) methodology. Neural network algorithms are employed to forecast the degradation parameters based on the EV batteries' aging history to develop a degradation model. The degradation model is integrated with the ECM to reflect the impacts of the cycle aging mechanism on battery parameters during operation. The developed model is tested under real-life load profiles to evaluate the life span of the batteries in various operating conditions. The methodology and the algorithms introduced in this paper can be considered the basis for Battery Management System (BMS) design and techno-economic analysis of such technologies.

Keywords: second life battery, electric vehicles, degradation, neural network

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1175 Application of Aquatic Plants for the Remediation of Organochlorine Pesticides from Keenjhar Lake

Authors: Soomal Hamza, Uzma Imran

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Organochlorine pesticides bio-accumulate into the fat of fish, birds, and animals through which it enters the human food cycle. Due to their persistence and stability in the environment, many health impacts are associated with them, most of which are carcinogenic in nature. In this study, the level of organochlorine pesticides has been detected in Keenjhar Lake and remediated using Rhizoremediation technique. 14 OC pesticides namely, Aldrin, Deldrin, Heptachlor, Heptachlor epoxide, Endrin, Endosulfun I and II, DDT, DDE, DDD, Alpha, Beta, Gamma BHC and two plants namely, Water Hyacinth and Slvinia Molesta were used in the system using pot experiment which processed for 11 days. A consortium was inoculated in both plants to increase its efficiency. Water samples were processed using liquide-liquid extraction. Sediments and roots samples were processed using Soxhlet method followed by clean-up and Gas Chromatography. Delta-BHC was the predominantly found in all samples with mean concentration (ppb) and standard deviation of 0.02 ± 0.14, 0.52 ± 0.68, 0.61 ± 0.06, in Water, Sediments and Roots samples respectively. The highest levels were of Endosulfan II in the samples of water, sediments and roots. Water Hyacinth proved to be better bioaccumulaor as compared to Silvinia Molesta. The pattern of compounds reduction rate by the end of experiment was Delta-BHC>DDD > Alpha-BHC > DDT> Heptachlor> H.Epoxide> Deldrin> Aldrin> Endrin> DDE> Endosulfun I > Endosulfun II. Not much significant difference was observed between the pots with the consortium and pots without the consortium addition. Phytoremediation is a promising technique, but more studies are required to assess the bioremediation potential of different aquatic plants and plant-endophyte relationship.

Keywords: aquatic plant, bio remediation, gas chromatography, liquid liquid extraction

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1174 Social Crises and Its Impact on the Environment: Case Study of Jos, Plateau State

Authors: A. B. Benshak, M. G. Yilkangnha, V. Y. Nanle

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Social crises and violent conflict can inflict direct (short-term) impact on the environment like poisoning water bodies, climate change, deforestation, destroying the chemical component of the soil due to the chemical and biological weapons used. It can also impact the environment indirectly (long-term), e.g., the destruction of political and economic infrastructure to manage the environmental resources and breaking down traditional conservation practices, population displacement and refugee flows which puts pressure on the already inadequate resources, infrastructure, facilities, amenities, services etc. This study therefore examines the impact of social crises on the environment in Jos Plateau State with emphasis on the long-term impact, analyze the relationship between crises and the environment and assess the perception of people on social crises because much work have concentrated on other repercussions such as the economy, health etc that are more politically expedient. The data for this research were collected mostly through interviews, questionnaire, dailies and reports on the subject matter. The data and findings were presented in tables and results showed that the environment is directly and indirectly impacted by crises and that these impacts can in turn result to a continuous cycle of violent activities if not addressed because of the inadequacies in the supply of infrastructural facilities, resources and so on caused by the inflow of displaced population. Recommendations were made on providing security to minimize conflict occurrences in Jos and its environs, minimizing the impact of social crises on the environment, provision of adequate infrastructural facilities to carter for population rise, renewal and regeneration schemes, etc. which will go a long way in mitigating the impact of crises on the environment.

Keywords: environment, impact, long-term, social crises

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1173 Numerical Analysis of Laminar Reflux Condensation from Gas-Vapour Mixtures in Vertical Parallel Plate Channels

Authors: Foad Hassaninejadafarahani, Scott Ormiston

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Reflux condensation occurs in a vertical channels and tubes when there is an upward core flow of vapor (or gas-vapor mixture) and a downward flow of the liquid film. The understanding of this condensation configuration is crucial in the design of reflux condensers, distillation columns, and in loss-of-coolant safety analyses in nuclear power plant steam generators. The unique feature of this flow is the upward flow of the vapor-gas mixture (or pure vapor) that retards the liquid flow via shear at the liquid-mixture interface. The present model solves the full, elliptic governing equations in both the film and the gas-vapor core flow. The computational mesh is non-orthogonal and adapts dynamically the phase interface, thus produces sharp and accurate interface. Shear forces and heat and mass transfer at the interface are accounted for fundamentally. This modeling is a big step ahead of current capabilities by removing the limitations of previous reflux condensation models which inherently cannot account for the detailed local balances of shear, mass, and heat transfer at the interface. Discretisation has been done based on a finite volume method and a co-located variable storage scheme. An in-house computer code was developed to implement the numerical solution scheme. Detailed results are presented for laminar reflux condensation from steam-air mixtures flowing in vertical parallel plate channels. The results include velocity and pressure profiles, as well as axial variations of film thickness, Nusselt number and interface gas mass fraction.

Keywords: Reflux, Condensation, CFD-Two Phase, Nusselt number

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1172 Complicating Representations of Domestic Violence Perpetration through a Qualitative Content Analysis and Socio-Ecological Approach

Authors: Charlotte Lucke

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This study contributes to the body of literature that analyzes and complicates oversimplified and sensationalized representations of trauma and violence through a close examination and complication of representations of perpetrators of domestic violence in the mass media. This study determines the ways the media frames perpetrators of domestic violence through a qualitative content analysis and socio-ecological approach to the perpetration of violence. While the qualitative analysis has not been carried out, through preliminary research, this study hypothesizes that the media represents perpetrators through tropes such as the 'predator' or 'offender,' or as a demonized 'other.' It is necessary to expose and work through such stereotypes because cultivation theory demonstrates that the mass media determines societal beliefs about and perceptions of the world. Thus, representations of domestic violence in the mass media can lead people to believe that perpetrators of violence are mere animals or criminals and overlook the trauma that many perpetrators experience. When the media represents perpetrators as pure evil, monsters, or absolute 'others,' it leaves out the complexities of what moves people to commit domestic violence. By analyzing and placing media representations of perpetrators into conversation with the socio-ecological approach to violence perpetration, this study complicates domestic violence stereotypes. The socio-ecological model allows researchers to consider the way the interplay between individuals and their families, friends, communities, and cultures can move people to act violently. Using this model, along with psychological and psychoanalytic approaches to the etiology of domestic violence, this paper argues that media stereotypes conceal the way people’s experiences of trauma, along with community and cultural norms, perpetuates the cycle of systemic trauma and violence in the home.

Keywords: domestic violence, media images, representing trauma, theorising trauma

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1171 Building Information Management in Context of Urban Spaces, Analysis of Current Use and Possibilities

Authors: Lucie Jirotková, Daniel Macek, Andrea Palazzo, Veronika Malinová

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Currently, the implementation of 3D models in the construction industry is gaining popularity. Countries around the world are developing their own modelling standards and implement the use of 3D models into their individual permitting processes. Another theme that needs to be addressed are public building spaces and their subsequent maintenance, where the usage of BIM methodology is directly offered. The significant benefit of the implementation of Building Information Management is the information transfer. The 3D model contains not only the spatial representation of the item shapes but also various parameters that are assigned to the individual elements, which are easily traceable, mainly because they are all stored in one place in the BIM model. However, it is important to keep the data in the models up to date to achieve useability of the model throughout the life cycle of the building. It is now becoming standard practice to use BIM models in the construction of buildings, however, the building environment is very often neglected. Especially in large-scale development projects, the public space of buildings is often forwarded to municipalities, which obtains the ownership and are in charge of its maintenance. A 3D model of the building surroundings would include both the above-ground visible elements of the development as well as the underground parts, such as the technological facilities of water features, electricity lines for public lighting, etc. The paper shows the possibilities of a model in the field of information for the handover of premises, the following maintenance and decision making. The attributes and spatial representation of the individual elements make the model a reliable foundation for the creation of "Smart Cities". The paper analyses the current use of the BIM methodology and presents the state-of-the-art possibilities of development.

Keywords: BIM model, urban space, BIM methodology, facility management

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1170 Removal of Polycyclic Aromatic Hydrocarbons Present in Tyre Pyrolytic Oil Using Low Cost Natural Adsorbents

Authors: Neha Budhwani

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Polycyclic aromatic hydrocarbons (PAHs) are formed during the pyrolysis of scrap tyres to produce tyre pyrolytic oil (TPO). Due to carcinogenic, mutagenic, and toxic properties PAHs are priority pollutants. Hence it is essential to remove PAHs from TPO before utilising TPO as a petroleum fuel alternative (to run the engine). Agricultural wastes have promising future to be utilized as biosorbent due to their cost effectiveness, abundant availability, high biosorption capacity and renewability. Various low cost adsorbents were prepared from natural sources. Uptake of PAHs present in tyre pyrolytic oil was investigated using various low-cost adsor¬bents of natural origin including sawdust (shiham), coconut fiber, neem bark, chitin, activated charcol. Adsorption experiments of different PAHs viz. naphthalene, acenaphthalene, biphenyl and anthracene have been carried out at ambient temperature (25°C) and at pH 7. It was observed that for any given PAH, the adsorption capacity increases with the lignin content. Freundlich constant kf and 1/n have been evaluated and it was found that the adsorption isotherms of PAHs were in agreement with a Freundlich model, while the uptake capacity of PAHs followed the order: activated charcoal> saw dust (shisham) > coconut fiber > chitin. The partition coefficients in acetone-water, and the adsorption constants at equilibrium, could be linearly correlated with octanol–water partition coefficients. It is observed that natural adsorbents are good alternative for PAHs removal. Sawdust of Dalbergia sissoo, a by-product of sawmills was found to be a promising adsorbent for the removal of PAHs present in TPO. It is observed that adsorbents studied were comparable to those of some conventional adsorbents.

Keywords: natural adsorbent, PAHs, TPO, coconut fiber, wood powder (shisham), naphthalene, acenaphthene, biphenyl and anthracene

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1169 The Proton Flow Battery for Storing Renewable Energy: Hydrogen Storage Capacity of Selected Activated Carbon Electrodes Made from Brown Coal

Authors: Amandeep Singh Oberoi, John Andrews, Alan L. Chaffee, Lachlan Ciddor

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Electrochemical storage of hydrogen in activated carbon electrodes as part of a reversible fuel cell offers a potentially attractive option for storing surplus electrical energy from inherently variable solar and wind energy resources. Such a system – which we have called a proton flow battery – promises to have roundtrip energy efficiency comparable to lithium ion batteries, while having higher gravimetric and volumetric energy densities. Activated carbons with high internal surface area, high pore volume, light weight and easy availability have attracted considerable research interest as a solid-state hydrogen storage medium. This paper compares the physical characteristics and hydrogen storage capacities of four activated carbon electrodes made by different methods from brown coal. The fabrication methods for these samples are explained. Their proton conductivity was measured using electrochemical impedance spectroscopy, and their hydrogen storage capacity by galvanostatic charging and discharging in a three-electrode electrolytic cell with 1 mol sulphuric acid as electrolyte. The highest hydrogen storage capacity obtained was 1.29 wt%, which compares favourably with metal hydrides used in commercially available solid-state hydrogen storages. The hydrogen storage capacity of the samples increased monotonically with increasing BET surface area (calculated from CO2 adsorption method). The results point the way towards selecting high-performing electrodes for proton flow batteries that the competitiveness of this energy storage technology.

Keywords: activated carbon, electrochemical hydrogen storage, proton flow battery, proton conductivity

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1168 Investment Trend Analysis of Dhaka Stock Exchange: A Comparative Study

Authors: Azaz Zaman, Mirazur Rahman

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Capital market is a crucial financial market place where companies and the government can raise long-term funds and, at the same time, investors get the opportunity to invest in the listed companies. Capital markets play a vital role not only in shifting the funds from surplus entity to deficit for investment, but also in the overall economic development of any developing country like Bangladesh. Being the first and biggest capital market of Bangladesh, Dhaka Stock Exchange (DSE) is the prime bourse of the country. The differences in the investment preference— among three broad categories of investors in DSE including individual investors, institutional investors, and government— are easily observed. Authors of this article have used five categories of investors such as sponsors or directors of the company, institutional investors, foreign investors, government, and the general public in order to present a comparative analysis of their investment patterns. Obtaining data on the percentage of investment by these five types of investors in different sectors from the DSE website, this study aims to analyze the sector-wise investment preference of these investors using August 2018 data. The study has found that the sponsors or directors of the company have the highest percentage of investment in the textile industry which is close to 16%. The Bangladesh government, as an investor, has the highest percentage of investment in the fuel & power sector, approximately 32%. It has also found that the mutual funds' sector is mostly financed by institutional investors, nearly 28%. Foreign investors have their most investments in the banking sector, which is close to 22%. It has also revealed that the textile sector is mostly financed by the general public, close to 17%. Nevertheless, general public, surprisingly, has the lowest percentage of investment in the telecommunication sector, which is 0.10%.

Keywords: stock market investment, Dhaka stock exchange, capital market, Bangladesh

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1167 Synergistic Effect of Curcumin and Insulin on GLUT4 Translocation in C2C12 Cell

Authors: Javad Mohiti-Ardekani, Shabodin Asadii, Ali Moradi

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Introduction: Curcumin, the yellow pigment in turmeric, has been shown as an anti-diabetic agent for centuries but only in recent few years, its mechanism of action has been under investigation. Some studies showed that curcumin might exert its anti-diabetic effect via increasing glucose transporter isotype-4 (GLUT4) gene and glycoprotein contents in cells. To investigate this possibility, we investigate the effects of extract and commercial curcumin with and without insulin on GLUT4 translocation from intracellular compartments of nuclear or endoplasmic reticulum membranes (N/ER) into the cytoplasmic membrane (CM). Methods and Material: C2C12 myoblastic cell line were seeded in DMEM plus 20 % FBS and differentiated to myotubes using 2 % horse serum. After myotubes formation, 40 µmolar Extract and Commercial curcumin, with or without insulin as intervention, and as control 1 % DMSO were added for 3 h. Cells were washed and homogenized followed by ultracentrifuge fractionation, protein separation by SDS-PAGE and GLUT4 detection using semi-quantitative Western blotting. Data analysis was done by two independent samples t-test for comparison of mean ± SD of GLUT4 percent in categories. GLUT4 contents were higher in CM groups curcumin and curcumin with insulin in comparison to 1 % DMSO-treated myotubes control group. Results: As our results have shown extract and commercial curcumin induces GLUT4 translocation from intra-cell into cell surface. The results have also shown synergic effect of curcumin on translocation of GLUT4 from intra-cell into cell surface in the presence of 100 nm insulin. Discussion: We conclude that curcumin may be a choice of type-2 diabetes mellitus treatment because its extract and commercial enhances GLUT4 contents in CM where it facilitates glucose entrance into the cell. However, it is necessary to trace the signaling pathways which are activated by curcumin.

Keywords: Curcumin, insulin, Diabetes type-2, GLUT4

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1166 Assessment of Cardioprotective Effect of Deferiprone on Doxorubicin-Induced Cardiac Toxicity in a Rat Model

Authors: Sadaf Kalhori

Abstract:

Introduction: Doxorubicin (DOX)-induced cardiotoxicity is widely known as the most severe complication of anthracycline-based chemotherapy in patients with cancer. It is unknown whether Deferiprone (DFP), could reduce the severity of DOX-induced cardiotoxicity by inhibiting free radical reactions. Thus, this study was performed to assess the protective effect of Deferiprone on DOX-induced cardiotoxicity in a rat model. Methods: The rats were divided into five groups. Group one was a control group. Group 2 was DOX (2 mg/kg/day, every other day for 12 days), and Group three to five which receiving DOX as in group 2 and DFP 75,100 and 150 mg/kg/day, for 19 days, respectively. DFP was starting 5 days prior to the first DOX injection and two days after the last DOX injection throughout the study. Electrocardiographic and hemodynamic studies, along with histopathological examination, were conducted. In addition, serum sample was taken and total cholesterol, Malone dialdehyde, triglyceride, albumin, AST, ALT, total protein, lactate dehydrogenase, total anti-oxidant and creatine kinase were assessed. Result: Our results showed the normal structure of endocardial, myocardial and pericardial in the control group. Pathologic data such as edema, hyperemia, bleeding, endocarditis, myocarditis and pericarditis, hyaline degeneration, cardiomyocyte necrosis, myofilament degeneration and nuclear chromatin changes were assessed in all groups. In the DOX group, all pathologic data was seen with mean grade of 2±1.25. In the DFP group with a dose of 75 and 100 mg, the mean grade was 1.41± 0.31 and 1±.23, respectively. In DFP group with a dose of 150, the pathologic data showed a milder change in comparison with other groups with e mean grade of 0.45 ±0.19. Most pathologic data in DFP groups showed significant changes in comparison with the DOX group (p < 0.001). Discussion: The results also showed that DFP treatment significantly improved DOX-induced heart damage, structural changes in the myocardium, and ventricular function. Our data confirm that DFP is protective against cardiovascular-related disorders induced by DOX. Clinical studies are needed to be involved to examine these findings in humans.

Keywords: cardiomyopathy, deferiprone, doxorubicin, rat

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1165 Micro-Ribonucleic Acid-21 as High Potential Prostate Cancer Biomarker

Authors: Regina R. Gunawan, Indwiani Astuti, H. Raden Danarto

Abstract:

Cancer is the leading cause of death worldwide. Cancer is caused by mutations that alter the function of normal human genes and give rise to cancer genes. MicroRNA (miRNA) is a small non-coding RNA that regulates the gen through complementary bond towards mRNA target and cause mRNA degradation. miRNA works by either promoting or suppressing cell proliferation. miRNA level expression in cancer may offer another value of miRNA as a biomarker in cancer diagnostic. miRNA-21 is believed to have a role in carcinogenesis by enhancing proliferation, anti-apoptosis, cell cycle progression and invasion of tumor cells. Hsa-miR-21-5p marker has been identified in Prostate Cancer (PCa) and Benign Prostatic Hyperplasia (BPH) patient’s urine. This research planned to explore the diagnostic performance of miR-21 to differentiate PCa and BPH patients. In this study, urine samples were collected from 20 PCa patients and 20 BPH patients. miR-21 relative expression against the reference gene was analyzed and compared between the two. miRNA expression was analyzed using the comparative quantification method to find the fold change. miR-21 validity in identifying PCa patients was performed by quantifying the sensitivity and specificity with the contingency table. miR-21 relative expression against miR-16 in PCa patient and in BPH patient has 12,98 differences in fold change. From a contingency table of Cq expression of miR-21 in identifying PCa patients from BPH patient, Cq miR-21 has 100% sensitivity and 75% specificity. miR-21 relative expression can be used in discriminating PCa from BPH by using a urine sample. Furthermore, the expression of miR-21 has higher sensitivity compared to PSA (Prostate specific antigen), therefore miR-21 has a high potential to be analyzed and developed more.

Keywords: benign prostate hyperplasia, biomarker, miRNA-21, prostate cancer

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1164 Climate Change Impacts, Vulnerability, and Adaptation among Rural Households in Ethiopia

Authors: Birtukan Atinkut Asmare

Abstract:

Climate change disproportionately affects many Africans who heavily rely on climate-exposed sectors such as rain-fed agriculture and fishing, rendering them highly vulnerable. Gender plays a significant role, as men and women experience unequal impacts and vulnerabilities due to gender norms, labor divisions, resource access, and power dynamics. Drawing on an integrated framework, this study sheds light on the gendered impacts of climate change on household’s livelihood, their vulnerability, and adaptation in rural Ethiopia's Lake Tana Basin. This study utilized mixed research methods, integrating diverse qualitative techniques such as focus group discussions, key informant interviews, and field observations, along with quantitative data gathered through household surveys. The findings reveal that women-headed households were more vulnerable to climate change than male-headed households. Flood was the major climate-induced hazards in the area that threatened the lives and livelihoods of households. In response to climate change, households undertook different adaptation measures such as agroforestry practices, crop diversification, seasonal migration, petty trading, charcoal and fuel wood sales. However, the adaptation strategies were slightly varied based on the gender of the household head. Women-headed households specifically engaged in fuelwood collection and selling and petty trading activities. The main constraints for adaptation were limited access to technologies, extension services, information, and financial services. Therefore, this research urges attention from research, policy, and advisory services on rural households who are trying to survive in the face of climate change.

Keywords: agriculture, climate change impacts, ethiopia, gender

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1163 Experimental Study of Hydrogen and Water Vapor Extraction from Helium with Zeolite Membranes for Tritium Processes

Authors: Rodrigo Antunes, Olga Borisevich, David Demange

Abstract:

The Tritium Laboratory Karlsruhe (TLK) has identified zeolite membranes as most promising for tritium processes in the future fusion reactors. Tritium diluted in purge gases or gaseous effluents, and present in both molecular and oxidized forms, can be pre-concentrated by a stage of zeolite membranes followed by a main downstream recovery stage (e.g., catalytic membrane reactor). Since 2011 several membrane zeolite samples have been tested to measure the membrane performances in the separation of hydrogen and water vapor from helium streams. These experiments were carried out in the ZIMT (Zeolite Inorganic Membranes for Tritium) facility where mass spectrometry and cold traps were used to measure the membranes’ performances. The membranes were tested at temperatures ranging from 25 °C up to 130 °C, at feed pressures between 1 and 3 bar, and typical feed flows of 2 l/min. During this experimental campaign, several zeolite-type membranes were studied: a hollow-fiber MFI nanocomposite membrane purchased from IRCELYON (France), and tubular MFI-ZSM5, NaA and H-SOD membranes purchased from Institute for Ceramic Technologies and Systems (IKTS, Germany). Among these membranes, only the MFI-based showed relevant performances for the H2/He separation, with rather high permeances (~0.5 – 0.7 μmol/sm2Pa for H2 at 25 °C for MFI-ZSM5), however with a limited ideal selectivity of around 2 for H2/He regardless of the feed concentration. Both MFI and NaA showed higher separation performances when water vapor was used instead; for example, at 30 °C, the separation factor for MFI-ZSM5 is approximately 10 and 38 for 0.2% and 10% H2O/He, respectively. The H-SOD evidenced to be considerably defective and therefore not considered for further experiments. In this contribution, a comprehensive analysis of the experimental methods and results obtained for the separation performance of different zeolite membranes during the past four years in inactive environment is given. These results are encouraging for the experimental campaign with molecular and oxidized tritium that will follow in 2017.

Keywords: gas separation, nuclear fusion, tritium processes, zeolite membranes

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1162 Environmental Degradation of Natural Resources in Broghil National Park in the High Mountains of Pakistan – Empirical Evidence From Local Community and Geoinformatics

Authors: Siddique Ullah Baig, Alisha Manzoor

Abstract:

The remotest, mountainous, and icy Broghil Valley is a high-profile protected area as a national park, which hosts one of the highest altitude permanent human settlements on the earth. This park hosts a distributed but diverse range of habitats. Due to a lack of infrastructures, higher altitudes, and harsh environmental conditions, poverty-stricken inhabitants mostly rely on its resources, causing ecological dis-balance. This study aims to investigate the environmental degradation of natural resources of the park based on empirical evidence from stakeholders and geoinformatics. The result shows that one-fourth of the park is a gently undulating basin dotted with water bodies / grass, and agricultural land and three fourth is entirely rugged with steep mountains and glaciers. There are virtually no forests as the arid cold tundra climate and high altitude prevent tree growth. Rapid three-decadal land cover changes have led to ecological disequilibrium of the park, narrowing the traditional diverse food base, decreasing the resilience of biodiversity and local livelihoods as crop-land has shifted towards fallow, alpine-grass to peat-land and snow/glacial ice area to bare-soil/rocks. The local community believes in exploiting whatever vegetation or organic material is available for use as food, fodder, and fuel. The permanent presence of the community and limited cost-effective options in the park will be a challenge forever to maintain undisturbed natural processes as the objective of a national park.

Keywords: Broghil National Park, natural resources, environmental degradation, land cover

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1161 Assessment of Potential Spontaneous Plants Seed Dispersal in Camels and Small Ruminants Faeces

Authors: H. Trabelsi, A. Chehma, I. Benseddik

Abstract:

Animals can play an important role in the seed dispersal cycle through the active or passive uptake of seeds and the subsequent external (epizoochory) or internal transport (endozoochory) of seeds. In Algeria, small ruminants and camels are generally conducted in extensive livestock exploiting the Saharan and steppe rangelands. To get an idea on the ecological potential role of these animals in the spontaneous plants proliferation, we propose to make a study of seeds dispersal and germination possibilities by camel faeces compared to those of small ruminants. Manual faeces decortication of the two animals categories has allowed to inventory 72 seed which 71% are in good condition, while 29% of the seeds that are encountered are partially altered and could not be identified. The species that have been identified, from small ruminants dung are weeds of cultures, while those identified from camel dung are spontaneous plants of Saharan rangeland. Concerning germination in the laboratory, only 3 species seeds were germinated from camel feces, whose germination rate varies from 25% to 100%. Contrary to Sheep-Goat feces, a single species germinated with 71%. The three months seed germination in greenhouse allowed to identify 10 species belonging to 4 botanical families (5 species from small ruminants dung and 3 species from Camel dung). In general, the results show the positive effect played by two animals categories for plants seed dispersal with the camel particularity for spontaneous plants due to its capacity to cover long distances in different rangeland types.

Keywords: Algeria, camel, endozoochory, seeds, sheep-goat, rangeland

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1160 J-Integral Method for Assessment of Structural Integrity of a Pressure Vessel

Authors: Karthik K. R, Viswanath V, Asraff A. K

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The first stage of a new-generation launch vehicle of ISRO makes use of large pressure vessels made of Aluminium alloy AA2219 to store fuel and oxidizer. These vessels have many weld joints that may contain cracks or crack-like defects during their fabrication. These defects may propagate across the vessel during pressure testing or while in service under the influence of tensile stresses leading to catastrophe. Though ductile materials exhibit significant stable crack growth prior to failure, it is not generally acceptable for an aerospace component. There is a need to predict the initiation of stable crack growth. The structural integrity of the vessel from fracture considerations can be studied by constructing the Failure Assessment Diagram (FAD) that accounts for both brittle fracture and plastic collapse. Critical crack sizes of the pressure vessel may be highly conservative if it is predicted from FAD alone. If the J-R curve for material under consideration is available apriori, the critical crack sizes can be predicted to a certain degree of accuracy. In this paper, a novel approach is proposed to predict the integrity of a weld in a pressure vessel made of AA2219 material. Fracture parameter ‘J-integral’ at the crack front, evaluated through finite element analyses, is used in the new procedure. Based on the simulation of tension tests carried out on SCT specimens by NASA, a cut-off value of J-integral value (J?ᵤₜ_ₒ??) is finalised. For the pressure vessel, J-integral at the crack front is evaluated through FE simulations incorporating different surface cracks at long seam weld in a cylinder and in dome petal welds. The obtained J-integral, at vessel level, is compared with a value of J?ᵤₜ_ₒ??, and the integrity of vessel weld in the presence of the surface crack is firmed up. The advantage of this methodology is that if SCT test data of any metal is available, the critical crack size in hardware fabricated using that material can be predicted to a better level of accuracy.

Keywords: FAD, j-integral, fracture, surface crack

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1159 Predictive Analytics in Oil and Gas Industry

Authors: Suchitra Chnadrashekhar

Abstract:

Earlier looked as a support function in an organization information technology has now become a critical utility to manage their daily operations. Organizations are processing huge amount of data which was unimaginable few decades before. This has opened the opportunity for IT sector to help industries across domains to handle the data in the most intelligent manner. Presence of IT has been a leverage for the Oil & Gas industry to store, manage and process the data in most efficient way possible thus deriving the economic value in their day-to-day operations. Proper synchronization between Operational data system and Information Technology system is the need of the hour. Predictive analytics supports oil and gas companies by addressing the challenge of critical equipment performance, life cycle, integrity, security, and increase their utilization. Predictive analytics go beyond early warning by providing insights into the roots of problems. To reach their full potential, oil and gas companies need to take a holistic or systems approach towards asset optimization and thus have the functional information at all levels of the organization in order to make the right decisions. This paper discusses how the use of predictive analysis in oil and gas industry is redefining the dynamics of this sector. Also, the paper will be supported by real time data and evaluation of the data for a given oil production asset on an application tool, SAS. The reason for using SAS as an application for our analysis is that SAS provides an analytics-based framework to improve uptimes, performance and availability of crucial assets while reducing the amount of unscheduled maintenance, thus minimizing maintenance-related costs and operation disruptions. With state-of-the-art analytics and reporting, we can predict maintenance problems before they happen and determine root causes in order to update processes for future prevention.

Keywords: hydrocarbon, information technology, SAS, predictive analytics

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1158 Design and Development of an 'Optimisation Controller' and a SCADA Based Monitoring System for Renewable Energy Management in Telecom Towers

Authors: M. Sundaram, H. R. Sanath Kumar, A. Ramprakash

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Energy saving is a key sustainability focus area for the Indian telecom industry today. This is especially true in rural India where energy consumption contributes to 70 % of the total network operating cost. In urban areas, the energy cost for network operation ranges between 15-30 %. This expenditure on energy as a result of the lack of grid power availability highlights a potential barrier to telecom industry growth. As a result of this, telecom tower companies switch to diesel generators, making them the second largest consumer of diesel in India, consuming over 2.5 billion litres per annum. The growing cost of energy due to increasing diesel prices and concerns over rising greenhouse emissions have caused these companies to look at other renewable energy options. Even the TRAI (Telecom Regulation Authority of India) has issued a number of guidelines to implement Renewable Energy Technologies (RETs) in the telecom towers as part of its ‘Implementation of Green Technologies in Telecom Sector’ initiative. Our proposal suggests the implementation of a Programmable Logic Controller (PLC) based ‘optimisation controller’ that can not only efficiently utilize the energy from RETs but also help to conserve the power used in the telecom towers. When there are multiple RETs available to supply energy, this controller will pick the optimum amount of energy from each RET based on the availability and feasibility at that point of time, reducing the dependence on diesel generators. For effective maintenance of the towers, we are planing to implement a SCADA based monitoring system along with the ‘optimization controller’.

Keywords: operation costs, consumption of fuel and carbon footprint, implementation of a programmable logic controller (PLC) based ‘optimisation controller’, efficient SCADA based monitoring system

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1157 A New Multi-Target, Multi-Agent Search and Rescue Path Planning Approach

Authors: Jean Berger, Nassirou Lo, Martin Noel

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Perfectly suited for natural or man-made emergency and disaster management situations such as flood, earthquakes, tornadoes, or tsunami, multi-target search path planning for a team of rescue agents is known to be computationally hard, and most techniques developed so far come short to successfully estimate optimality gap. A novel mixed-integer linear programming (MIP) formulation is proposed to optimally solve the multi-target multi-agent discrete search and rescue (SAR) path planning problem. Aimed at maximizing cumulative probability of successful target detection, it captures anticipated feedback information associated with possible observation outcomes resulting from projected path execution, while modeling agent discrete actions over all possible moving directions. Problem modeling further takes advantage of network representation to encompass decision variables, expedite compact constraint specification, and lead to substantial problem-solving speed-up. The proposed MIP approach uses CPLEX optimization machinery, efficiently computing near-optimal solutions for practical size problems, while giving a robust upper bound obtained from Lagrangean integrality constraint relaxation. Should eventually a target be positively detected during plan execution, a new problem instance would simply be reformulated from the current state, and then solved over the next decision cycle. A computational experiment shows the feasibility and the value of the proposed approach.

Keywords: search path planning, search and rescue, multi-agent, mixed-integer linear programming, optimization

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1156 Carbon Dioxide (CO₂) and Methane (CH₄) Fluxes from Irrigated Wheat in a Subtropical Floodplain Soil Increased by Reduced Tillage, Residue Retention, and Nitrogen Application Rate

Authors: R. Begum, M. M. R. Jahangir, M. Jahiruddin, M. R. Islam, M. M. Rahman, M. B. Hossain, P. Hossain

Abstract:

Quantifying carbon (C) sequestration in soils is necessary to help better understand the effect of agricultural practices on the C cycle. The estimated contribution of agricultural carbon dioxide (CO₂) and methane (CH₄) to global warming potential (GWP) has a wide range. The underlying causes of this huge uncertainty are the difficulties to predict the regional CO₂ and CH₄ loss due to the lack of experimental evidence on CO₂ and CH₄ emissions and associated drivers. The CH₄ and CO₂ emissions were measured in irrigated wheat in subtropical floodplain soils which have been under two soil disturbance levels (strip vs. conventional tillage; ST vs. CT being both with 30% residue retention) and three N fertilizer rates (60, 100, and 140% of the recommended N fertilizer dose, RD) in annual wheat (Triticum aestivum)-mungbean (Vigna radiata)-rice (Oryza sativa L) for seven consecutive years. The highest CH₄ and CO₂ emission peak was observed on day 3 after urea application in both tillages except CO₂ flux in CT. Nitrogen fertilizer application rate significantly influenced mean and cumulative CH₄ and CO₂ fluxes. The CH₄ and CO₂ fluxes decreased in an optimum dose of N fertilizer except for ST for CH₄. The CO₂ emission significantly showed higher emission at minimum (60% of RD) fertilizer application at both tillages. Soil microbial biomass carbon (MBC), organic carbon (SOC), Particulate organic carbon (POC), permanganate oxidisable carbon (POXC), basal respiration (BR) were significantly higher in ST which were negative and significantly correlated with CO₂. However, POC and POXC were positively and significantly correlated with CH₄ emission.

Keywords: carbon dioxide emissions, methane emission, nitrogen rate, tillage

Procedia PDF Downloads 110