Search results for: Fuzzy sliding mode controller
Commenced in January 2007
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Edition: International
Paper Count: 3381

Search results for: Fuzzy sliding mode controller

531 Impact of Development Induced Displaced on Tribal Indigenous Women of North East India

Authors: Bitopi Dutta

Abstract:

Forced Displacement of marginalised groups has been widely debated whole across the world, including India. This paper will do a gender analysis of Development Induced Displacement(DID) in tribal indigenous societies of North East India (NEI), a region that is frequently quoted as a relatively gender equal society as compared to the other parts of India. The central argument of the paper concerns how patriarchies in the discourses of the state and societies work together in shaping a particular gendered experience for women (and men) - in this context a violent gendered transformation in displaced indigenous communities. The primary analysis of the paper will be centered on the acquisition of Common Property Resources (CPRs) under the Land Law of India which has devastating consequences for the tribal women since CPRs forms the basis of their high status, identity and autonomy. Tracing the trajectory of DID in the NEI since 1947 to 2010, this paper will locate the violent gendered transition that these tribal societies have undergone during this period vis.a.vis their tradition which was grounded on a far more gender equal worldview. The paper will place this argument in terms of the lost status and impoverishment of tribal women in the social and economic domain reflected in terms of loss of property and land ownership rights, monetisation of the tribal economy under the sole custody of the men, forced internalisation of this reduced status by the women themselves and so on. DID in this sense will not only be understood as only physical displacement, but also as social and cultural displacement. Interviews of people displaced/affected by the development projects will be the primary mode of data collection which will be supplemented with documentary research using Government Data, and local archives of the region.

Keywords: common property resources, displacement, north east India, tribal, women

Procedia PDF Downloads 139
530 Effect of Collaborative Learning on Development of Process Skills and Attitude to Wards Science

Authors: Shri Krishna Mishra, Badri Yadav

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Effect of collaborative learning on development of process skills and attitude towards science is It rightly said that the destiny of the nation is shaped inside its classroom. Classroom is a place where the pupil and teacher interact purposefully to gain knowledge. Teaching is the principal mode of education. It can be called a transaction between teacher and pupil, in which one transmits knowledge to other. The teaching learning process consists of three important components, the pupils, the teacher and the curriculum; the classroom is the collection of students of their own individual abilities and needs. In the present classroom teaching learners are either persuasive recipient or passive observant. The school environment leading to low-achievement we have to try better to develop in the young mind. Children are the sticks of dynamite, bundles of energy and potential power waiting to be ignited. Guide them carefully to a place where their potentialities and strength will be used to build a better world. Man’s future depends to large extent on scientific advances and development of productive activity. Science is considered as an important subject in school curricular. The education commission (1964-66) has suggested that science education is necessary for all children at school stage. It is essential to develop children’s logical and critical thinking. But these days thinking process and academic achievement of students have been suppressed by competitive environment of our schools. How the students perceive each other and interact with one another is a neglected aspect of instruction. In the constructivist perspective learning in a process of construction of knowledge. Learners actively construct their own knowledge by connecting new ideas to existing ideas on the basis of materials/ activities presented to them (experience).

Keywords: effect of collaborative learning, development of process skills, science education, attitude towards science

Procedia PDF Downloads 251
529 Understanding Inhibitory Mechanism of the Selective Inhibitors of Cdk5/p25 Complex by Molecular Modeling Studies

Authors: Amir Zeb, Shailima Rampogu, Minky Son, Ayoung Baek, Sang H. Yoon, Keun W. Lee

Abstract:

Neurotoxic insults activate calpain, which in turn produces truncated p25 from p35. p25 forms hyperactivated Cdk5/p25 complex, and thereby induces severe neuropathological aberrations including hyperphosphorylated tau, neuroinflammation, apoptosis, and neuronal death. Inhibition of Cdk5/p25 complex alleviates aberrant phosphorylation of tau to mitigate AD pathology. PHA-793887 and Roscovitine have been investigated as selective inhibitors of Cdk5/p25 with IC50 values 5nM and 160nM, respectively, but their mechanistic studies remain unknown. Herein, computational simulations have explored the binding mode and interaction mechanism of PHA-793887 and Roscovitine with Cdk5/p25. Docking results suggested that PHA-793887 and Rsocovitine have occupied the ATP-binding site of Cdk5 and obtained highest docking (GOLD) score of 66.54 and 84.03, respectively. Furthermore, molecular dynamics (MD) simulation demonstrated that PHA-793887 and Roscovitine established stable RMSD of 1.09 Å and 1.48 Å with Cdk5/p25, respectively. Profiling of polar interactions suggested that each inhibitor formed hydrogen bonds (H-bond) with catalytic residues of Cdk5 and could remain stable throughout the molecular dynamics simulation. Additionally, binding free energy calculation by molecular mechanics/Poisson–Boltzmann surface area (MM/PBSA) suggested that PHA-793887 and Roscovitine had lowest binding free energies of -150.05 kJ/mol and -113.14 kJ/mol, respectively with Cdk5/p25. Free energy decomposition demonstrated that polar energy by H-bond between the Glu81 of Cdk5 and PHA-793887 is the essential factor to make PHA-793887 highly selective towards Cdk5/p25. Overall, this study provided substantial evidences to explore mechanistic interactions of the selective inhibitors of Cdk5/p25 and could be used as fundamental considerations in the development of structure-based selective inhibitors of Cdk5/p25.

Keywords: Cdk5/p25 inhibition, molecular modeling of Cdk5/p25, PHA-793887 and roscovitine, selective inhibition of Cdk5/p25

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528 Cloud and Natural Language Processing (NLP) to Solve the Problem of Service Continuity

Authors: Mohammed Tou, Adel Toumoh

Abstract:

The availability of IT services within organizations has become increasingly important; however, in an interconnected world favoring the distribution and offshoring of organizational information system components, availability is directly based on the constancy and uninterrupted flow of the Internet. Internet attendance guarantees the continuity of IT services. In this communication, we introduce paradigms around the concept of service continuity, as well as the technical approaches and methodologies leading to its resolution. As the heart of the problem is indeed the non-continuity of service, we first start by framing the notion of continuity in the context of services offered by the information system and identify the failures resulting from the discontinuity; thus, we refer to related research to extract the tools and technological paradigms allowing the implementation of solutions that guarantee a minimum of service continuity. If the main element causing continuity is the availability of the Internet, it is obvious to look for an alternative path, which is a conventional PSTN telephone network. To complete the chain of solutions, we mainly used concepts such as voice and speech recognition, AI, NLP, and cloud computing. The research led us to introduce an important element between the user and the service: the request represented by a voice message. Thus, the broker guarantees the delivery of the message to the right recipient service, as well as the response to the user. All of these elements are orchestrated by a pipeline that guarantees the integrity of the request and response. The concepts related to speech recognition are used for the initiation of the process of the solution, along with the combination of NLP, with its two statistical approaches and neural networks, and cloud technology secures the solution in both directions. The targeted solution does not replace 100 \ 100 the availability, by default, of the service; however, our research aims for a minimum of continuity by preventing the organizational information system from being put into total shutdown mode.

Keywords: Cloud, PSTN, NPL, NLU, AI, MTTR, MTBF, RPO, RTO, SLA, SLO, LSR, SRS

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527 Individual Cylinder Ignition Advance Control Algorithms of the Aircraft Piston Engine

Authors: G. Barański, P. Kacejko, M. Wendeker

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The impact of the ignition advance control algorithms of the ASz-62IR-16X aircraft piston engine on a combustion process has been presented in this paper. This aircraft engine is a nine-cylinder 1000 hp engine with a special electronic control ignition system. This engine has two spark plugs per cylinder with an ignition advance angle dependent on load and the rotational speed of the crankshaft. Accordingly, in most cases, these angles are not optimal for power generated. The scope of this paper is focused on developing algorithms to control the ignition advance angle in an electronic ignition control system of an engine. For this type of engine, i.e. radial engine, an ignition advance angle should be controlled independently for each cylinder because of the design of such an engine and its crankshaft system. The ignition advance angle is controlled in an open-loop way, which means that the control signal (i.e. ignition advance angle) is determined according to the previously developed maps, i.e. recorded tables of the correlation between the ignition advance angle and engine speed and load. Load can be measured by engine crankshaft speed or intake manifold pressure. Due to a limited memory of a controller, the impact of other independent variables (such as cylinder head temperature or knock) on the ignition advance angle is given as a series of one-dimensional arrays known as corrective characteristics. The value of the ignition advance angle specified combines the value calculated from the primary characteristics and several correction factors calculated from correction characteristics. Individual cylinder control can proceed in line with certain indicators determined from pressure registered in a combustion chamber. Control is assumed to be based on the following indicators: maximum pressure, maximum pressure angle, indicated mean effective pressure. Additionally, a knocking combustion indicator was defined. Individual control can be applied to a single set of spark plugs only, which results from two fundamental ideas behind designing a control system. Independent operation of two ignition control systems – if two control systems operate simultaneously. It is assumed that the entire individual control should be performed for a front spark plug only and a rear spark plug shall be controlled with a fixed (or specific) offset relative to the front one or from a reference map. The developed algorithms will be verified by simulation and engine test sand experiments. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: algorithm, combustion process, radial engine, spark plug

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526 Multiple-Channel Piezoelectric Actuated Tunable Optical Filter for WDM Application

Authors: Hailu Dessalegn, T. Srinivas

Abstract:

We propose new multiple-channel piezoelectric (PZT) actuated tunable optical filter based on racetrack multi-ring resonators for wavelength de-multiplexing network applications. We design tunable eight-channel wavelength de-multiplexer consisting of eight cascaded PZT actuated tunable multi-ring resonator filter with a channel spacing of 1.6 nm. The filter for each channel is basically structured on a suspended beam, sandwiched with piezoelectric material and built in integrated ring resonators which are placed on the middle of the beam to gain uniform stress and linearly varying longitudinal strain. A reference single mode serially coupled multi stage racetrack ring resonator with the same radii and coupling length is designed with a line width of 0.8974 nm with a flat top pass band at 1dB of 0.5205 nm and free spectral range of about 14.9 nm. In each channel, a small change in the perimeter of the rings is introduced to establish the shift in resonance wavelength as per the defined channel spacing. As a result, when a DC voltage is applied, the beams will elongate, which involves mechanical deformation of the ring resonators that induces a stress and a strain, which brings a change in refractive index and perimeter of the rings leading to change in the output spectrum shift providing the tunability of central wavelength in each channel. Simultaneous wave length shift as high as 45.54 pm/V has been achieved with negligible tunability variation in the eight channel tunable optical filter proportional to the DC voltage applied in the structure, and it is capable of tuning up to 3.45 nm in each channel with a maximum loss difference of 0.22 dB in the tuning range and out of band rejection ratio of 35 dB, with a low channel crosstalk ≤ 30 dB.

Keywords: optical MEMS, piezoelectric (PZT) actuation, tunable optical filter, wavelength de-multiplexer

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525 Comparison of Different Hydrograph Routing Techniques in XPSTORM Modelling Software: A Case Study

Authors: Fatema Akram, Mohammad Golam Rasul, Mohammad Masud Kamal Khan, Md. Sharif Imam Ibne Amir

Abstract:

A variety of routing techniques are available to develop surface runoff hydrographs from rainfall. The selection of runoff routing method is very vital as it is directly related to the type of watershed and the required degree of accuracy. There are different modelling softwares available to explore the rainfall-runoff process in urban areas. XPSTORM, a link-node based, integrated storm-water modelling software, has been used in this study for developing surface runoff hydrograph for a Golf course area located in Rockhampton in Central Queensland in Australia. Four commonly used methods, namely SWMM runoff, Kinematic wave, Laurenson, and Time-Area are employed to generate runoff hydrograph for design storm of this study area. In runoff mode of XPSTORM, the rainfall, infiltration, evaporation and depression storage for sub-catchments were simulated and the runoff from the sub-catchment to collection node was calculated. The simulation results are presented, discussed and compared. The total surface runoff generated by SWMM runoff, Kinematic wave and Time-Area methods are found to be reasonably close, which indicates any of these methods can be used for developing runoff hydrograph of the study area. Laurenson method produces a comparatively less amount of surface runoff, however, it creates highest peak of surface runoff among all which may be suitable for hilly region. Although the Laurenson hydrograph technique is widely acceptable surface runoff routing technique in Queensland (Australia), extensive investigation is recommended with detailed topographic and hydrologic data in order to assess its suitability for use in the case study area.

Keywords: ARI, design storm, IFD, rainfall temporal pattern, routing techniques, surface runoff, XPSTORM

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524 Analysis of Travel Behavior Patterns of Frequent Passengers after the Section Shutdown of Urban Rail Transit - Taking the Huaqiao Section of Shanghai Metro Line 11 Shutdown During the COVID-19 Epidemic as an Example

Authors: Hongyun Li, Zhibin Jiang

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The travel of passengers in the urban rail transit network is influenced by changes in network structure and operational status, and the response of individual travel preferences to these changes also varies. Firstly, the influence of the suspension of urban rail transit line sections on passenger travel along the line is analyzed. Secondly, passenger travel trajectories containing multi-dimensional semantics are described based on network UD data. Next, passenger panel data based on spatio-temporal sequences is constructed to achieve frequent passenger clustering. Then, the Graph Convolutional Network (GCN) is used to model and identify the changes in travel modes of different types of frequent passengers. Finally, taking Shanghai Metro Line 11 as an example, the travel behavior patterns of frequent passengers after the Huaqiao section shutdown during the COVID-19 epidemic are analyzed. The results showed that after the section shutdown, most passengers would transfer to the nearest Anting station for boarding, while some passengers would transfer to other stations for boarding or cancel their travels directly. Among the passengers who transferred to Anting station for boarding, most of passengers maintained the original normalized travel mode, a small number of passengers waited for a few days before transferring to Anting station for boarding, and only a few number of passengers stopped traveling at Anting station or transferred to other stations after a few days of boarding on Anting station. The results can provide a basis for understanding urban rail transit passenger travel patterns and improving the accuracy of passenger flow prediction in abnormal operation scenarios.

Keywords: urban rail transit, section shutdown, frequent passenger, travel behavior pattern

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523 A Pilot Study of Bangkok High School Students’ Satisfaction Towards Online Learning Platform During Covid-19 Pandemic

Authors: Aung Aung Kyi, Khin Khin Aye

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The mode of teaching and learning has been changed dramatically due to the Covid-19 pandemic that made schools close and students may have been away from the campus. However, many schools all over the countries are helping students to facilitate e-learning through online teaching and learning platform. Regarding this, Sarasas bilingual school in Bangkok conducted the high school students’ satisfaction survey since it is important for every school to improve its quality of education that must meet the students' need. For the good of the school's reputation, the purpose of the study is to examine the level of satisfaction that enhances the best services in the future. This study applied random sampling techniques and the data were collected using a self-administered survey. Descriptive analysis and independent sample t-tests were used to measure the importance of satisfaction components. The results showed G-11 (A) students were extremely satisfied with “Accessibility of course resources and materials through online platform” and “Ontime homework submission” while G-11 (B) students were extremely satisfied with “Teacher assisted with guiding my learning activities” and “Course teacher for this online course interacted with me in a timely fashion”. Additionally, they were also satisfied with a clear understanding of the teacher’s introduction during online learning. A significant difference in the satisfaction was observed between G-11 (A) and G-11 (B) students in terms of “A clear understanding on introduction was given by the teacher at the beginning of this online course”(P=0.03), “Teacher assisted with guiding my learning activities” (P=0.003), and “Comfortable surrounding during online learning” (P=0.02). With regard to gender, it has been seen that female high school students were extremely satisfied with the amount of course interaction with their teacher and her guidance with learning activities during online learning. By understanding the survey assessment, schools can improve their quality of education through the best digital educational platform that helps satisfy their students in the future.

Keywords: Bangkok high school students., covid-19 pandemic, online learning platform, satisfaction

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522 State Rescaling of the Urban Development in Hong Kong after the Reunification: A Case Study of the Planning Process of the Hong Kong Section of the Guangzhou-Shenzhen-Hong Kong Express Rail Link

Authors: Zhihua Xu

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In the era of globalization, the urban question is increasingly being posed in the form of a scale question. Scale theory provides a new perspective for analyzing various dynamics and their influences on urban development. After the reunification, how the government of the Hong Kong Special Administrative Region (SAR) interacts with the actors at various scales and carries out state rescaling are the keys to exploring the issue of urban development and governance in Hong Kong. This paper examines the entire planning process of the Hong Kong Section of the Guangzhou-Shenzhen-Hong Kong Express Rail Link, from project conception, design, to consultation, and fund application, to identify the actors at different scales involved in the process, and analyze the modes and consequences of their interaction. This study shows that after the reunification, the Hong Kong SAR Government takes the initiative to scale up to expand its hinterland. Intergovernmental institutional cooperation is an important mode of state rescaling for the Hong Kong SAR government. Meanwhile, the gradually growing civil society plays an important role in the rescaling of urban development. Local actors use scalar politics to construct discourses and take actions at multiple scales to challenge the government’s proposal and trigger a discussion on the project throughout the Hong Kong society. The case study of Hong Kong can deepen the understanding of state rescaling of territorial organizations in the context of institutional transformation and enrich the theoretical connotation of state rescaling. It also helps the Mainland government to better understand the case of Hong Kong and formulate appropriate.

Keywords: Hong Kong, state rescaling, scalar politics, Hong Kong section of the Guangzhou-Shenzhen-Hong Kong express rail link, urban governance

Procedia PDF Downloads 181
521 Peptidoglycan Vaccine-On-Chip against a Lipopolysaccharide-Induced Experimental Sepsis Model

Authors: Katerina Bakela, Ioanna Zerva, Irene Athanassakis

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Lipopolysaccharide (LPS) is commonly used in murine sepsis models, which are largely associated with immunosuppression (incretion of MDSCs cells and Tregs, imbalance of inflammatory/anti-inflammatory cytokines) and collapse of the immune system. After adapting the LPS treatment to the needs of locally bred BALB/c mice, the present study explored the protective role of Micrococcus luteus peptidoglycan (PG) pre-activated vaccine-on chip in endotoxemia. The established protocol consisted of five daily intraperitoneal injections of 0.2mg/g LPS. Such protocol allowed longer survival, necessary in the prospect of the therapeutic treatment application. The so-called vaccine-on-chip consists of a 3-dimensional laser micro-texture Si-scaffold loaded with BALB/c mouse macrophages and activated in vitro with 1μg/ml PG, which exert its action upon subcutaneous implantation. The LPS treatment significantly decreased CD4+, CD8+, CD3z+, and CD19+ cells, while increasing myeloid-derived suppressor cells (MDSCs), CD25+, and Foxp3+ cells. These results were accompanied by increased arginase-1 activity in spleen cell lysates and production of IL-6, TNF-a, and IL-18 while acquiring severe sepsis phenotype as defined by the murine sepsis scoring. The in vivo application of PG pre-activated vaccine-on chip significantly decreased the percent of CD11b+, Gr1+, CD25+, Foxp3+ cells, and arginase-1 activity in the spleen of LPS-treated animals, while decreasing IL-6 and TNF-a in the serum, allowing survival to all animals tested and rescuing the severity of sepsis phenotype. In conclusion, these results reveal a promising mode of action of PG pre-activated vaccine-on chip in LPS endotoxemia, strengthening; thus, the use of treatment is septic patients.

Keywords: myeloid-derived suppressor cells, peptidoglycan, sepsis, Si-scaffolds

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520 Investigation of Wood Chips as Internal Carbon Source Supporting Denitrification Process in Domestic Wastewater Treatment

Authors: Ruth Lorivi, Jianzheng Li, John J. Ambuchi, Kaiwen Deng

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Nitrogen removal from wastewater is accomplished by nitrification and denitrification processes. Successful denitrification requires carbon, therefore, if placed after biochemical oxygen demand (BOD) and nitrification process, a carbon source has to be re-introduced into the water. To avoid adding a carbon source, denitrification is usually placed before BOD and nitrification processes. This process however involves recycling the nitrified effluent. In this study wood chips were used as internal carbon source which enabled placement of denitrification after BOD and nitrification process without effluent recycling. To investigate the efficiency of a wood packed aerobic-anaerobic baffled reactor on carbon and nutrients removal from domestic wastewater, a three compartment baffled reactor was presented. Each of the three compartments was packed with 329 g wood chips 1x1cm acting as an internal carbon source for denitrification. The proposed mode of operation was aerobic-anoxic-anaerobic (OAA) with no effluent recycling. The operating temperature, hydraulic retention time (HRT), dissolved oxygen (DO) and pH were 24 ± 2 , 24 h, less than 4 mg/L and 7 ± 1 respectively. The removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total nitrogen (TN) attained was 99, 87 and 83% respectively. TN removal rate was limited by nitrification as 97% of ammonia converted into nitrate and nitrite was denitrified. These results show that application of wood chips in wastewater treatment processes is an efficient internal carbon source. 

Keywords: aerobic-anaerobic baffled reactor, denitrification, nitrification, wood chip

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519 A Computational Investigation of Knocking Tendency in a Hydrogen-Fueled SI Engine

Authors: Hammam Aljabri, Hong G. Im

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Hydrogen is a promising future fuel to support the transition of the energy sector toward carbon neutrality. The direct utilization of H2 in Internal Combustion Engines (ICEs) is possible, and this technology faces mainly two challenges; high NOx emissions and severe knocking at mid to high loads. In this study, we numerically investigated the potential of H2 combustion in a truck-size engine operated in SI mode. To mitigate the knocking nature of H2 combustion, we have focused on studying the effects of three primary parameters; the compression ratio (CR), the air-fuel ratio, and the spark time. The baseline case was set using a CR of 16.5 and an equivalence ratio of 0.35. In simulations, the auto-ignition tendency was evaluated based on the maximum pressure rise rate and the local pressure fluctuations at the monitoring points set along the wall of the combustion chamber. To mitigate the auto-ignition tendency while enabling a wider range of engine operation, the effect of lowering the compression ratio was assessed. The results indicate that by lowering the compression ratio from 16.5:1 to 12.5:1, an indicated thermal efficiency of 47.5% can be achieved. Aiming to restrain the auto-ignition while maintaining good efficiency, a reduction in the equivalence ratio was examined under different compression ratios. The result indicates that higher compression ratios will require lower equivalence ratios, and due to practical limitations, a lower equivalence ratio of 0.25 was set as the limit. Using a compression ratio of 13.5 combined with an equivalence ratio of 0.3 resulted in an indicated thermal efficiency of 48.6%, that is, at a fixed spark time. It is found that under such lean conditions, the incomplete combustion losses and exhaust losses were high. Thus, advancing the spark time was assessed as a possible solution. The results demonstrated the advantages of advancing the spark time, where an indicated thermal efficiency exceeding 50% was achieved using a compression ratio of 14.5:1 and an equivalence ratio of 0.25.

Keywords: hydrogen, combustion, engine knock, SI engine

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518 Improving 99mTc-tetrofosmin Myocardial Perfusion Images by Time Subtraction Technique

Authors: Yasuyuki Takahashi, Hayato Ishimura, Masao Miyagawa, Teruhito Mochizuki

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Quantitative measurement of myocardium perfusion is possible with single photon emission computed tomography (SPECT) using a semiconductor detector. However, accumulation of 99mTc-tetrofosmin in the liver may make it difficult to assess that accurately in the inferior myocardium. Our idea is to reduce the high accumulation in the liver by using dynamic SPECT imaging and a technique called time subtraction. We evaluated the performance of a new SPECT system with a cadmium-zinc-telluride solid-state semi- conductor detector (Discovery NM 530c; GE Healthcare). Our system acquired list-mode raw data over 10 minutes for a typical patient. From the data, ten SPECT images were reconstructed, one for every minute of acquired data. Reconstruction with the semiconductor detector was based on an implementation of a 3-D iterative Bayesian reconstruction algorithm. We studied 20 patients with coronary artery disease (mean age 75.4 ± 12.1 years; range 42-86; 16 males and 4 females). In each subject, 259 MBq of 99mTc-tetrofosmin was injected intravenously. We performed both a phantom and a clinical study using dynamic SPECT. An approximation to a liver-only image is obtained by reconstructing an image from the early projections during which time the liver accumulation dominates (0.5~2.5 minutes SPECT image-5~10 minutes SPECT image). The extracted liver-only image is then subtracted from a later SPECT image that shows both the liver and the myocardial uptake (5~10 minutes SPECT image-liver-only image). The time subtraction of liver was possible in both a phantom and the clinical study. The visualization of the inferior myocardium was improved. In past reports, higher accumulation in the myocardium due to the overlap of the liver is un-diagnosable. Using our time subtraction method, the image quality of the 99mTc-tetorofosmin myocardial SPECT image is considerably improved.

Keywords: 99mTc-tetrofosmin, dynamic SPECT, time subtraction, semiconductor detector

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517 Simulation-Based Validation of Safe Human-Robot-Collaboration

Authors: Titanilla Komenda

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Human-machine-collaboration defines a direct interaction between humans and machines to fulfil specific tasks. Those so-called collaborative machines are used without fencing and interact with humans in predefined workspaces. Even though, human-machine-collaboration enables a flexible adaption to variable degrees of freedom, industrial applications are rarely found. The reasons for this are not technical progress but rather limitations in planning processes ensuring safety for operators. Until now, humans and machines were mainly considered separately in the planning process, focusing on ergonomics and system performance respectively. Within human-machine-collaboration, those aspects must not be seen in isolation from each other but rather need to be analysed in interaction. Furthermore, a simulation model is needed that can validate the system performance and ensure the safety for the operator at any given time. Following on from this, a holistic simulation model is presented, enabling a simulative representation of collaborative tasks – including both, humans and machines. The presented model does not only include a geometry and a motion model of interacting humans and machines but also a numerical behaviour model of humans as well as a Boole’s probabilistic sensor model. With this, error scenarios can be simulated by validating system behaviour in unplanned situations. As these models can be defined on the basis of Failure Mode and Effects Analysis as well as probabilities of errors, the implementation in a collaborative model is discussed and evaluated regarding limitations and simulation times. The functionality of the model is shown on industrial applications by comparing simulation results with video data. The analysis shows the impact of considering human factors in the planning process in contrast to only meeting system performance. In this sense, an optimisation function is presented that meets the trade-off between human and machine factors and aids in a successful and safe realisation of collaborative scenarios.

Keywords: human-machine-system, human-robot-collaboration, safety, simulation

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516 Simulation of Bird Strike on Airplane Wings by Using SPH Methodology

Authors: Tuğçe Kiper Elibol, İbrahim Uslan, Mehmet Ali Guler, Murat Buyuk, Uğur Yolum

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According to the FAA report, 142603 bird strikes were reported for a period of 24 years, between 1990 – 2013. Bird strike with aerospace structures not only threaten the flight security but also cause financial loss and puts life in danger. The statistics show that most of the bird strikes are happening with the nose and the leading edge of the wings. Also, a substantial amount of bird strikes is absorbed by the jet engines and causes damage on blades and engine body. Crash proof designs are required to overcome the possibility of catastrophic failure of the airplane. Using computational methods for bird strike analysis during the product development phase has considerable importance in terms of cost saving. Clearly, using simulation techniques to reduce the number of reference tests can dramatically affect the total cost of an aircraft, where for bird strike often full-scale tests are considered. Therefore, development of validated numerical models is required that can replace preliminary tests and accelerate the design cycle. In this study, to verify the simulation parameters for a bird strike analysis, several different numerical options are studied for an impact case against a primitive structure. Then, a representative bird mode is generated with the verified parameters and collided against the leading edge of a training aircraft wing, where each structural member of the wing was explicitly modeled. A nonlinear explicit dynamics finite element code, LS-DYNA was used for the bird impact simulations. SPH methodology was used to model the behavior of the bird. Dynamic behavior of the wing superstructure was observed and will be used for further design optimization purposes.

Keywords: bird impact, bird strike, finite element modeling, smoothed particle hydrodynamics

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515 Investigation of Failure Mechanisms of Composite Laminates with Delamination and Repaired with Bolts

Authors: Shuxin Li, Peihao Song, Haixiao Hu, Dongfeng Cao

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The interactive deformation and failure mechanisms, including local bucking/delamination propagation and global bucking, are investigated in this paper with numerical simulation and validation with experimental results. Three dimensional numerical models using ABAQUS brick elements combined with cohesive elements and contact elements are developed to simulate the deformation and failure characteristics of composite laminates with and without delamination under compressive loading. The zero-thickness cohesive elements are inserted on the possible path of delamination propagation, and the inter-laminate behavior is characterized by the mixed-mode traction-separation law. The numerical simulations identified the complex feature of interaction among local buckling and/or delamination propagation and final global bucking for composite laminates with delamination under compressive loading. Firstly there is an interaction between the local buckling and delamination propagation, i.e., local buckling induces delamination propagation, and then delamination growth further enhances the local buckling. Secondly, the interaction between the out-plan deformation caused by local buckling and the global bucking deformation results in final failure of the composite laminates. The simulation results are validated by the good agreement with the experimental results published in the literature. The numerical simulation validated with experimental results revealed that the degradation of the load capacity, in particular of the compressive strength of composite structures with delamination, is mainly attributed to the combined local buckling/delamination propagation effects. Consequently, a simple field-bolt repair approach that can hinder the local buckling and prevent delamination growth is explored. The analysis and simulation results demonstrated field-bolt repair could effectively restore compressive strength of composite laminates with delamination.

Keywords: cohesive elements, composite laminates, delamination, local and global bucking, field-bolt repair

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514 The Effects of Street Network Layout on Walking to School

Authors: Ayse Ozbil, Gorsev Argin, Demet Yesiltepe

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Data for this cross-sectional study were drawn from questionnaires conducted in 10 elementary schools (1000 students, ages 12-14) located in Istanbul, Turkey. School environments (1600 meter buffers around the school) were evaluated through GIS-based land-use data (parcel level land use density) and street-level topography. Street networks within the same buffers were evaluated by using angular segment analysis (Integration and Choice) implemented in Depthmap as well as two segment-based connectivity measures, namely Metric and Directional Reach implemented in GIS. Segment Angular Integration measures how accessible each space from all the others within the radius using the least angle measure of distance. Segment Angular Choice which measures how many times a space is selected on journeys between all pairs of origins and destinations. Metric Reach captures the density of streets and street connections accessible from each individual road segment. Directional Reach measures the extent to which the entire street network is accessible with few direction changes. In addition, socio-economic characteristics (annual income, car ownership, education-level) of parents, obtained from parental questionnaires, were also included in the analysis. It is shown that surrounding street network configuration is strongly associated with both walk-mode shares and average walking distances to/from schools when controlling for parental socio-demographic attributes as well as land-use compositions and topographic features in school environments. More specifically, findings suggest that the scale at which urban form has an impact on pedestrian travel is considerably larger than a few blocks around the school.

Keywords: Istanbul, street network layout, urban form, walking to/from school

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513 A Retrospective Study of Pain Management Strategies for Pediatric Hypospadias Surgery in a Tertiary Care Hospital in Western Rajasthan

Authors: Darshana Rathod, Kirtikumar Rathod, Kamlesh Kumari, Abhilasha Motghare

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Background and Aims: Hypospadias is one of the common congenital anomalies in males. Various modalities are used for pain management, including caudal, penile, pudendal, ring blocks, and systemic analgesics. There has yet to be a consensus regarding the most effective and safe analgesic method for controlling pain in these children. We planned this study to determine our institute's pain management practices for hypospadias surgeries. Material and Methods: This retrospective cohort study reviewed 150 children with hypospadias undergoing surgery from January 2020 to December 2023. Data regarding the mode of pain management, postoperative opioid requirement, PACU discharge, and complications was collected from the records. Results: For postoperative pain, 33 (22%) children received caudal block, 60 (40%) penile block, and 57 (38%) were managed by intravenous analgesics. A significant difference was found in the three groups, with the IV analgesic group requiring significantly higher opioid boluses in PACU [43 (75.4%) required two boluses (p < 0.05)]. The difference in PACU discharge time among the three groups was statistically significant (p< 0.05), with IV analgesics groups having the highest (55 mins [47, 60]), the Caudal group at 35mins (30, 40), and the dorsal penile block group at 35mins (25, 40). There was no significant difference in complications like edema, meatal stenosis, urethra-cutaneous fistula, or wound dehiscence among all three groups. Conclusion: Intravenous analgesics and regional blocks like caudal and penile blocks are the common pain management modalities in our institute. The regional blocks are effective in managing pain in the postoperative period and are not significantly associated with complications.

Keywords: caudal block, hypospadias, pain management, penile block

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512 CyberSteer: Cyber-Human Approach for Safely Shaping Autonomous Robotic Behavior to Comply with Human Intention

Authors: Vinicius G. Goecks, Gregory M. Gremillion, William D. Nothwang

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Modern approaches to train intelligent agents rely on prolonged training sessions, high amounts of input data, and multiple interactions with the environment. This restricts the application of these learning algorithms in robotics and real-world applications, in which there is low tolerance to inadequate actions, interactions are expensive, and real-time processing and action are required. This paper addresses this issue introducing CyberSteer, a novel approach to efficiently design intrinsic reward functions based on human intention to guide deep reinforcement learning agents with no environment-dependent rewards. CyberSteer uses non-expert human operators for initial demonstration of a given task or desired behavior. The trajectories collected are used to train a behavior cloning deep neural network that asynchronously runs in the background and suggests actions to the deep reinforcement learning module. An intrinsic reward is computed based on the similarity between actions suggested and taken by the deep reinforcement learning algorithm commanding the agent. This intrinsic reward can also be reshaped through additional human demonstration or critique. This approach removes the need for environment-dependent or hand-engineered rewards while still being able to safely shape the behavior of autonomous robotic agents, in this case, based on human intention. CyberSteer is tested in a high-fidelity unmanned aerial vehicle simulation environment, the Microsoft AirSim. The simulated aerial robot performs collision avoidance through a clustered forest environment using forward-looking depth sensing and roll, pitch, and yaw references angle commands to the flight controller. This approach shows that the behavior of robotic systems can be shaped in a reduced amount of time when guided by a non-expert human, who is only aware of the high-level goals of the task. Decreasing the amount of training time required and increasing safety during training maneuvers will allow for faster deployment of intelligent robotic agents in dynamic real-world applications.

Keywords: human-robot interaction, intelligent robots, robot learning, semisupervised learning, unmanned aerial vehicles

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511 White Wine Discrimination Based on Deconvoluted Surface Enhanced Raman Spectroscopy Signals

Authors: Dana Alina Magdas, Nicoleta Simona Vedeanu, Ioana Feher, Rares Stiufiuc

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Food and beverages authentication using rapid and non-expensive analytical tools represents nowadays an important challenge. In this regard, the potential of vibrational techniques in food authentication has gained an increased attention during the last years. For wines discrimination, Raman spectroscopy appears more feasible to be used as compared with IR (infrared) spectroscopy, because of the relatively weak water bending mode in the vibrational spectroscopy fingerprint range. Despite this, the use of Raman technique in wine discrimination is in an early stage. Taking this into consideration, the wine discrimination potential of surface-enhanced Raman scattering (SERS) technique is reported in the present work. The novelty of this study, compared with the previously reported studies, concerning the application of vibrational techniques in wine discrimination consists in the fact that the present work presents the wines differentiation based on the individual signals obtained from deconvoluted spectra. In order to achieve wines classification with respect to variety, geographical origin and vintage, the peaks intensities obtained after spectra deconvolution were compared using supervised chemometric methods like Linear Discriminant Analysis (LDA). For this purpose, a set of 20 white Romanian wines from different viticultural Romanian regions four varieties, was considered. Chemometric methods applied directly to row SERS experimental spectra proved their efficiency, but discrimination markers identification found to be very difficult due to the overlapped signals as well as for the band shifts. By using this approach, a better general view related to the differences that appear among the wines in terms of compositional differentiation could be reached.

Keywords: chemometry, SERS, variety, wines discrimination

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510 Defining Processes of Gender Restructuring: The Case of Displaced Tribal Communities of North East India

Authors: Bitopi Dutta

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Development Induced Displacement (DID) of subaltern groups has been an issue of intense debate in India. This research will do a gender analysis of displacement induced by the mining projects in tribal indigenous societies of North East India, centering on the primary research question which is 'How does DID reorder gendered relationship in tribal matrilineal societies?' This paper will not focus primarily on the impacts of the displacement induced by coal mining on indigenous tribal women in the North East India; it will rather study 'what' are the processes that lead to these transformations and 'how' do they operate. In doing so, the paper will locate the cracks in traditional social systems that the discourse of displacement manipulates for its own benefit. DID in this sense will not only be understood as only physical displacement, but also as social and cultural displacement. The study will cover one matrilineal tribe in the state of Meghalaya in the North East India affected by several coal mining projects in the last 30 years. In-depth unstructured interviews used to collect life narratives will be the primary mode of data collection because the indigenous culture of the tribes in Meghalaya, including the matrilineal tribes, is based on oral history where knowledge and experiences produced under a tradition of oral history exist in a continuum. This is unlike modern societies which produce knowledge in a compartmentalized system. An interview guide designed around specific themes will be used rather than specific questions to ensure the flow of narratives from the interviewee. In addition to this, a number of focus groups will be held. The data collected through the life narrative will be supplemented and contextualized through documentary research using government data, and local media sources of the region.

Keywords: displacement, gender-relations, matriliny, mining

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509 Towards Sustainable Consumption: A Framework for Assessing Supplier's Commitment

Authors: O. O. Oguntoye

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Product consumption constitutes an important consideration for sustainable development. Seeing how product consumption could be highly unsustainable, coupled with how existing policies on corporate responsibility do not particularly address the consumption aspect of product lifecycle, conducting this research became necessary. The research makes an attempt to provide a framework by which to gauge corporate responsibility of product suppliers in terms of their commitment towards the sustainable consumption of their products. Through an exploration of relevant literature, independently established ideas with which to assess a given product supplier were galvanised into a four-criterion framework. The criteria are: (1) Embeddedness of consumption as a factor in corporate sustainability policy, (2) Level of understanding of consumption behaviour, (3) Breadth of behaviour-influencing strategies adopted, and (4) Inclusiveness for all main dimensions of sustainability. This resulting framework was then applied in a case study involving a UK-based furniture supplier where interviews and content analysis of corporate documents were used as the mode for primary data collection. From the case study, it was found that the supplier had performed to different levels across the four themes of the assessment. Two major areas for improvement were however identified – one is for the furniture supplier to focus more proactively on understanding consumption behaviour and, two is for it to widen the scope of its current strategies for enhancing sustainable consumption of supplied furniture. As a generalisation, the framework presented here makes it possible for companies to reflect with a sense of guidance, how they have demonstrated commitment towards sustainable consumption through their values, culture, and operations. It also provides a foundation for developing standardized assessment which the current widely used frameworks such as the GRI, the Global Compact, and others do not cover. While these popularly used frameworks mainly focus on sustainability of companies within the production and supply chain management contexts (i.e. mostly ‘upstream’), the framework here provides an extension by bringing the ‘downstream’ or consumer bit into light.

Keywords: corporate sustainability, design for sustainable consumption, extended producer responsibility, sustainable consumer behaviour

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508 Approaches to Valuing Ecosystem Services in Agroecosystems From the Perspectives of Ecological Economics and Agroecology

Authors: Sandra Cecilia Bautista-Rodríguez, Vladimir Melgarejo

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Climate change, loss of ecosystems, increasing poverty, increasing marginalization of rural communities and declining food security are global issues that require urgent attention. In this regard, a great deal of research has focused on how agroecosystems respond to these challenges as they provide ecosystem services (ES) that lead to higher levels of resilience, adaptation, productivity and self-sufficiency. Hence, the valuing of ecosystem services plays an important role in the decision-making process for the design and management of agroecosystems. This paper aims to define the link between ecosystem service valuation methods and ES value dimensions in agroecosystems from ecological economics and agroecology. The method used to identify valuation methodologies was a literature review in the fields of Agroecology and Ecological Economics, based on a strategy of information search and classification. The conceptual framework of the work is based on the multidimensionality of value, considering the social, ecological, political, technological and economic dimensions. Likewise, the valuation process requires consideration of the ecosystem function associated with ES, such as regulation, habitat, production and information functions. In this way, valuation methods for ES in agroecosystems can integrate more than one value dimension and at least one ecosystem function. The results allow correlating the ecosystem functions with the ecosystem services valued, and the specific tools or models used, the dimensions and valuation methods. The main methodologies identified are multi-criteria valuation (1), deliberative - consultative valuation (2), valuation based on system dynamics modeling (3), valuation through energy or biophysical balances (4), valuation through fuzzy logic modeling (5), valuation based on agent-based modeling (6). Amongst the main conclusions, it is highlighted that the system dynamics modeling approach has a high potential for development in valuation processes, due to its ability to integrate other methods, especially multi-criteria valuation and energy and biophysical balances, to describe through causal cycles the interrelationships between ecosystem services, the dimensions of value in agroecosystems, thus showing the relationships between the value of ecosystem services and the welfare of communities. As for methodological challenges, it is relevant to achieve the integration of tools and models provided by different methods, to incorporate the characteristics of a complex system such as the agroecosystem, which allows reducing the limitations in the processes of valuation of ES.

Keywords: ecological economics, agroecosystems, ecosystem services, valuation of ecosystem services

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507 Utilising Indigenous Knowledge to Design Dykes in Malawi

Authors: Martin Kleynhans, Margot Soler, Gavin Quibell

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Malawi is one of the world’s poorest nations and consequently, the design of flood risk management infrastructure comes with a different set of challenges. There is a lack of good quality hydromet data, both in spatial terms and in the quality thereof and the challenge in the design of flood risk management infrastructure is compounded by the fact that maintenance is almost completely non-existent and that solutions have to be simple to be effective. Solutions should not require any further resources to remain functional after completion, and they should be resilient. They also have to be cost effective. The Lower Shire Valley of Malawi suffers from frequent flood events. Various flood risk management interventions have been designed across the valley during the course of the Shire River Basin Management Project – Phase I, and due to the data poor environment, indigenous knowledge was relied upon to a great extent for hydrological and hydraulic model calibration and verification. However, indigenous knowledge comes with the caveat that it is ‘fuzzy’ and that it can be manipulated for political reasons. The experience in the Lower Shire valley suggests that indigenous knowledge is unlikely to invent a problem where none exists, but that flood depths and extents may be exaggerated to secure prioritization of the intervention. Indigenous knowledge relies on the memory of a community and cannot foresee events that exceed past experience, that could occur differently to those that have occurred in the past, or where flood management interventions change the flow regime. This complicates communication of planned interventions to local inhabitants. Indigenous knowledge is, for the most part, intuitive, but flooding can sometimes be counter intuitive, and the rural poor may have a lower trust of technology. Due to a near complete lack of maintenance of infrastructure, infrastructure has to be designed with no moving parts and no requirement for energy inputs. This precludes pumps, valves, flap gates and sophisticated warning systems. Designs of dykes during this project included ‘flood warning spillways’, that double up as pedestrian and animal crossing points, which provide warning of impending dangerous water levels behind dykes to residents before water levels that could cause a possible dyke failure are reached. Locally available materials and erosion protection using vegetation were used wherever possible to keep costs down.

Keywords: design of dykes in low-income countries, flood warning spillways, indigenous knowledge, Malawi

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506 Dynamic Thin Film Morphology near the Contact Line of a Condensing Droplet: Nanoscale Resolution

Authors: Abbasali Abouei Mehrizi, Hao Wang

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The thin film region is so important in heat transfer process due to its low thermal resistance. On the other hand, the dynamic contact angle is crucial boundary condition in numerical simulations. While different modeling contains different assumption of the microscopic contact angle, none of them has experimental evidence for their assumption, and the contact line movement mechanism still remains vague. The experimental investigation in complete wetting is more popular than partial wetting, especially in nanoscale resolution when there is sharp variation in thin film profile in partial wetting. In the present study, an experimental investigation of water film morphology near the triple phase contact line during the condensation is performed. The state-of-the-art tapping-mode atomic force microscopy (TM-AFM) was used to get the high-resolution film profile goes down to 2 nm from the contact line. The droplet was put in saturated chamber. The pristine silicon wafer was used as a smooth substrate. The substrate was heated by PI film heater. So the chamber would be over saturated by droplet evaporation. By turning off the heater, water vapor gradually started condensing on the droplet and the droplet advanced. The advancing speed was less than 20 nm/s. The dominant results indicate that in contrast to nonvolatile liquid, the film profile goes down straightly to the surface till 2 nm from the substrate. However, small bending has been observed below 20 nm, occasionally. So, it can be claimed that for the low condensation rate the microscopic contact angle equals to the optically detectable macroscopic contact angle. This result can be used to simplify the heat transfer modeling in partial wetting. The experimental result of the equality of microscopic and macroscopic contact angle can be used as a solid evidence for using this boundary condition in numerical simulation.

Keywords: advancing, condensation, microscopic contact angle, partial wetting

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505 Quantitative Evaluation of Supported Catalysts Key Properties from Electron Tomography Studies: Assessing Accuracy Using Material-Realistic 3D-Models

Authors: Ainouna Bouziane

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The ability of Electron Tomography to recover the 3D structure of catalysts, with spatial resolution in the subnanometer scale, has been widely explored and reviewed in the last decades. A variety of experimental techniques, based either on Transmission Electron Microscopy (TEM) or Scanning Transmission Electron Microscopy (STEM) have been used to reveal different features of nanostructured catalysts in 3D, but High Angle Annular Dark Field imaging in STEM mode (HAADF-STEM) stands out as the most frequently used, given its chemical sensitivity and avoidance of imaging artifacts related to diffraction phenomena when dealing with crystalline materials. In this regard, our group has developed a methodology that combines image denoising by undecimated wavelet transforms (UWT) with automated, advanced segmentation procedures and parameter selection methods using CS-TVM (Compressed Sensing-total variation minimization) algorithms to reveal more reliable quantitative information out of the 3D characterization studies. However, evaluating the accuracy of the magnitudes estimated from the segmented volumes is also an important issue that has not been properly addressed yet, because a perfectly known reference is needed. The problem particularly complicates in the case of multicomponent material systems. To tackle this key question, we have developed a methodology that incorporates volume reconstruction/segmentation methods. In particular, we have established an approach to evaluate, in quantitative terms, the accuracy of TVM reconstructions, which considers the influence of relevant experimental parameters like the range of tilt angles, image noise level or object orientation. The approach is based on the analysis of material-realistic, 3D phantoms, which include the most relevant features of the system under analysis.

Keywords: electron tomography, supported catalysts, nanometrology, error assessment

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504 Molecular Design and Synthesis of Heterocycles Based Anticancer Agents

Authors: Amna J. Ghith, Khaled Abu Zid, Khairia Youssef, Nasser Saad

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Backgrounds: The multikinase and vascular endothelial growth factor (VEGF) receptor inhibitors interrupt the pathway by which angiogenesis becomes established and promulgated, resulting in the inadequate nourishment of metastatic disease. VEGFR-2 has been the principal target of anti-angiogenic therapies. We disclose the new thieno pyrimidines as inhibitors of VEGFR-2 designed by a molecular modeling approach with increased synergistic activity and decreased side effects. Purpose: 2-substituted thieno pyrimidines are designed and synthesized with anticipated anticancer activity based on its in silico molecular docking study that supports the initial pharmacophoric hypothesis with a same binding mode of interaction at the ATP-binding site of VEGFR-2 (PDB 2QU5) with high docking score. Methods: A series of compounds were designed using discovery studio 4.1/CDOCKER with a rational that mimic the pharmacophoric features present in the reported active compounds that targeted VEGFR-2. An in silico ADMET study was also performed to validate the bioavailability of the newly designed compounds. Results: The Compounds to be synthesized showed interaction energy comparable to or within the range of the benzimidazole inhibitor ligand when docked with VEGFR-2. ADMET study showed comparable results most of the compounds showed absorption within (95-99) zone varying according to different substitutions attached to thieno pyrimidine ring system. Conclusions: A series of 2-subsituted thienopyrimidines are to be synthesized with anticipated anticancer activity and according to docking study structure requirement for the design of VEGFR-2 inhibitors which can act as powerful anticancer agents.

Keywords: docking, discovery studio 4.1/CDOCKER, heterocycles based anticancer agents, 2-subsituted thienopyrimidines

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503 Repeated Batch Cultivation: A Novel Empty and Fill Strategy for the Enhanced Production of a Biodegradable Polymer, Polyhydroxy Alkanoate by Alcaligenes latus

Authors: Geeta Gahlawat, Ashok Kumar Srivastava

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In the present study, a simple drain and fill protocol strategy of repeated batch was adopted for enhancement in polyhydroxyalkanoates (PHAs) production using alcaligenes latus DSM 1124. Repeated batch strategy helped in increasing the longevity of otherwise decaying culture in the bioreactor by supplementing fresh substrates during each cycle of repeated-batch. The main advantages of repeated batch are its ease of operation, enhancement of culture stability towards contamination, minimization of pre-culture effects and maintenance of organism at high growth rates. The cultivation of A. latus was carried out in 7 L bioreactor containing 4 L optimized nutrient medium and a comparison with the batch mode fermentation was done to evaluate the performance of repeated batch in terms of PHAs accumulation and productivity. The statistically optimized medium recipe consisted of: 25 g/L Sucrose, 2.8 g/L (NH4)2SO4, 3.25 g/L KH2PO4, 3.25 g/L Na2HPO4, 0.2 g/L MgSO4, 1.5 mL/L trace element solution. In this strategy, 20% (v/v) of the culture broth was removed from the reactor and supplemented with an equal volume of fresh medium when sucrose concentration inside the reactor decreased below 8 g/L. The fermenter was operated for three repeated batch cycles and fresh nutrient feeding was done at 27 h, 48 h, and 60 h. Repeated batch operation resulted in a total biomass of 27.89 g/L and PHAs concentration 20.55 g/L at the end of 69 h which was a marked improvement as compared to batch cultivation (8.71 g/L biomass and 6.24 g/L PHAs). This strategy demonstrated 3.3 fold and 1.8 fold increase in PHAs concentration and volumetric productivity, respectively as compared to batch cultivation. Repeated batch cultivation strategy had also the benefit of avoiding non-productive time period required for cleaning, refilling and sterilization of bioreactor, thereby increasing the overall volumetric productivity and making the entire process cost-effective too.

Keywords: alcaligenes, biodegradation, polyhydroxyalkanoates, repeated batch

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502 Structuring Highly Iterative Product Development Projects by Using Agile-Indicators

Authors: Guenther Schuh, Michael Riesener, Frederic Diels

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Nowadays, manufacturing companies are faced with the challenge of meeting heterogeneous customer requirements in short product life cycles with a variety of product functions. So far, some of the functional requirements remain unknown until late stages of the product development. A way to handle these uncertainties is the highly iterative product development (HIP) approach. By structuring the development project as a highly iterative process, this method provides customer oriented and marketable products. There are first approaches for combined, hybrid models comprising deterministic-normative methods like the Stage-Gate process and empirical-adaptive development methods like SCRUM on a project management level. However, almost unconsidered is the question, which development scopes can preferably be realized with either empirical-adaptive or deterministic-normative approaches. In this context, a development scope constitutes a self-contained section of the overall development objective. Therefore, this paper focuses on a methodology that deals with the uncertainty of requirements within the early development stages and the corresponding selection of the most appropriate development approach. For this purpose, internal influencing factors like a company’s technology ability, the prototype manufacturability and the potential solution space as well as external factors like the market accuracy, relevance and volatility will be analyzed and combined into an Agile-Indicator. The Agile-Indicator is derived in three steps. First of all, it is necessary to rate each internal and external factor in terms of the importance for the overall development task. Secondly, each requirement has to be evaluated for every single internal and external factor appropriate to their suitability for empirical-adaptive development. Finally, the total sums of internal and external side are composed in the Agile-Indicator. Thus, the Agile-Indicator constitutes a company-specific and application-related criterion, on which the allocation of empirical-adaptive and deterministic-normative development scopes can be made. In a last step, this indicator will be used for a specific clustering of development scopes by application of the fuzzy c-means (FCM) clustering algorithm. The FCM-method determines sub-clusters within functional clusters based on the empirical-adaptive environmental impact of the Agile-Indicator. By means of the methodology presented in this paper, it is possible to classify requirements, which are uncertainly carried out by the market, into empirical-adaptive or deterministic-normative development scopes.

Keywords: agile, highly iterative development, agile-indicator, product development

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