Search results for: safe separation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2938

Search results for: safe separation

2248 Influence of Intra-Yarn Permeability on Mesoscale Permeability of Plain Weave and 3D Fabrics

Authors: Debabrata Adhikari, Mikhail Matveev, Louise Brown, Andy Long, Jan Kočí

Abstract:

A good understanding of mesoscale permeability of complex architectures in fibrous porous preforms is of particular interest in order to achieve efficient and cost-effective resin impregnation of liquid composite molding (LCM). Fabrics used in structural reinforcements are typically woven or stitched. However, 3D fabric reinforcement is of particular interest because of the versatility in the weaving pattern with the binder yarn and in-plain yarn arrangements to manufacture thick composite parts, overcome the limitation in delamination, improve toughness etc. To predict the permeability based on the available pore spaces between the inter yarn spaces, unit cell-based computational fluid dynamics models have been using the Stokes Darcy model. Typically, the preform consists of an arrangement of yarns with spacing in the order of mm, wherein each yarn consists of thousands of filaments with spacing in the order of μm. The fluid flow during infusion exchanges the mass between the intra and inter yarn channels, meaning there is no dead-end of flow between the mesopore in the inter yarn space and the micropore in the yarn. Several studies have employed the Brinkman equation to take into account the flow through dual-scale porosity reinforcement to estimate their permeability. Furthermore, to reduce the computational effort of dual scale flow, scale separation criteria based on the ratio between yarn permeability to the yarn spacing was also proposed to quantify the dual scale and negligible micro-scale flow regime for the prediction of mesoscale permeability. In the present work, the key parameter to identify the influence of intra yarn permeability on the mesoscale permeability has been investigated with the systematic study of weft and warp yarn spacing on the plane weave as well as the position of binder yarn and number of in-plane yarn layers on 3D weave fabric. The permeability tensor has been estimated using an OpenFOAM-based model for the various weave pattern with idealized geometry of yarn implemented using open-source software TexGen. Additionally, scale separation criterion has been established based on the various configuration of yarn permeability for the 3D fabric with both the isotropic and anisotropic yarn from Gebart’s model. It was observed that the variation of mesoscale permeability Kxx within 30% when the isotropic porous yarn is considered for a 3D fabric with binder yarn. Furthermore, the permeability model developed in this study will be used for multi-objective optimizations of the preform mesoscale geometry in terms of yarn spacing, binder pattern, and a number of layers with an aim to obtain improved permeability and reduced void content during the LCM process.

Keywords: permeability, 3D fabric, dual-scale flow, liquid composite molding

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2247 Screening of Ionic Liquids for Hydrogen Sulfide Removal Using COSMO-RS

Authors: Zulaika Mohd Khasiran

Abstract:

The capability of ionic liquids in various applications makes them attracted by many researchers. They have potential to be developed as “green” solvents for gas separation, especially H2S gas. In this work, it is attempted to predict the solubility of hydrogen sulfide (H2S) in ILs by COSMO-RS method. Since H2S is a toxic pollutant, it is difficult to work on it in the laboratory, therefore an appropriate model will be necessary in prior work. The COSMO-RS method is implemented to predict the Henry’s law constants and activity coefficient of H2S in 140 ILs with various combinations of cations and anions. It is found by the screening that more H2S can be absorbed in ILs with [Cl] and [Ac] anion. The solubility of H2S in ILs with different alkyl chain at the cations not much affected and with different type of cations are slightly influence H2S capture capacities. Even though the cations do not affect much in solubility of H2S, we still need to consider the effectiveness of cation in different way. The prediction results only show their physical absorption ability, but the absorption of H2S need to be consider chemically to get high capacity of absorption of H2S.

Keywords: H2S, hydrogen sulfide, ionic liquids, COSMO-RS

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2246 Teamwork of Teachers in Kindergarten and School Heads Implementing Focused Leadership

Authors: Vilma Zydziunaite, Simona Kersiene

Abstract:

The concept of focused leadership means that the leader gathers the entire community in various ways to communicate and cooperate with each other, to share their knowledge and responsibility, to get involved in problem-solving, to create a safe and trusting environment and to satisfy the needs and interests of each community member. The study's aim is to analyze the teamwork of teachers working in kindergartens and schools and its CEOs by implementing confused leadership. A mixed research design was used for the research study. Quantitative research used the teamwork test "Team-Puls" (2003). Data is processed by the IBM SPSS version 29.0 software package. Semi-structured interviews were used for data collection, and qualitative content analysis was applied for data analysis. The results of quantitative research show that there is no statistically significant difference between the evaluation averages of kindergarten and school teachers. Likewise, the effectiveness and evaluation of teacher teamwork in educational institutions depend on different characteristics and processes, such as the number of participating teachers, the involvement of the institution's administration or the stages of team formation. In the qualitative research, the components of the focused leadership categories applied by the kindergarten and school CEOs emerged. The categories reflect the components of shared leadership. In the study, the sharing of responsibilities and cooperation among teachers and the sharing of knowledge among themselves is distinguished. This shows that the action takes place between the teachers when they participate in the processes voluntarily, according to their wishes or for certain reasons. Distributed leadership components occurs when leadership responsibility is extended beyond the school CEO. The components of servant leadership are expressed when the CEO achieves organizational goals in the service of others. Servant leadership is helping and striving for others, creating a safe environment. The level of the educational institution does not affect working teachers in the evaluation of working in a team. Giving freedom to teachers, the role of the CEO is dividing responsibilities and creating cooperation between teachers as well as ensuring teachers' interests, needs, emotional well-being and professional development.

Keywords: teamwork, school, teacher, school CEO, school environment, mixed research, Team-Puls test, semi-structured interview, questioning survey, qualitative content analysis, focused leadership, teacher leadership

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2245 Organic Permeation Properties of Hydrophobic Silica Membranes with Different Functional Groups

Authors: Sadao Araki, Daisuke Gondo, Satoshi Imasaka, Hideki Yamamoto

Abstract:

The separation of organic compounds from aqueous solutions is a key technology for recycling valuable organic compounds and for the treatment of wastewater. The wastewater from chemical plants often contains organic compounds such as ethyl acetate (EA), methylethyl ketone (MEK) and isopropyl alcohol (IPA). In this study, we prepared hydrophobic silica membranes by a sol-gel method. We used phenyltrimethoxysilane (PhTMS), ethyltrimethoxysilan (ETMS), Propyltrimethoxysilane (PrTMS), N-butyltrimethoxysilane (BTMS), N-Hexyltrimethoxysilane (HTMS) as silica sources to introduce each functional groups on the membrane surface. Cetyltrimethyl ammonium bromide (CTAB) was used as a molecular template to create suitable pore that enable the permeation of organic compounds. These membranes with five different functional groups were characterized by SEM, FT-IR, and permporometry. Thicknesses and pore diameters of silica layer for all membrane were about 1.0 μm and about 1 nm, respectively. In other words, functional groups had an insignificant effect on the membrane thicknesses and the formation of the pore by CTAB. We confirmed the effect of functional groups on the flux and separation factor for ethyl acetate (EA), methyl ethyl ketone, acetone and 1-butanol (1-BtOH) /water mixtures. All membranes showed a high flux for ethyl acetate compared with other compounds. In particular, the hydrophobic silica membrane prepared by using BTMS showed 0.75 kg m-2 h-1 of flux for EA. For all membranes, the fluxes of organic compounds showed the large values in the order corresponding to EA > MEK > acetone > 1-BtOH. On the other hand, carbon chain length of functional groups among ETMS, PrTMS, BTMS, PrTMS and HTMS did not have a major effect on the organic flux. Although we confirmed the relationship between organic fluxes and organic molecular diameters or fugacity of organic compounds, these factors had a low correlation with organic fluxes. It is considered that these factors affect the diffusivity. Generally, permeation through membranes is based on the diffusivity and solubility. Therefore, it is deemed that organic fluxes through these hydrophobic membranes are strongly influenced by solubility. We tried to estimate the organic fluxes by Hansen solubility parameter (HSP). HSP, which is based on the cohesion energy per molar volume and is composed of dispersion forces (δd), intermolecular dipole interactions (δp), and hydrogen-bonding interactions (δh), has recently attracted attention as a means for evaluating the resolution and aggregation behavior. Evaluation of solubility for two substances can be represented by using the Ra [(MPa)1/2] value, meaning the distance of HSPs for both of substances. A smaller Ra value means a higher solubility for each substance. On the other hand, it can be estimated that the substances with large Ra value show low solubility. We established the correlation equation, which was based on Ra, of organic flux at low concentrations of organic compounds and at 295-325 K.

Keywords: hydrophobic, membrane, Hansen solubility parameter, functional group

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2244 Pervaporation of Dimethyl Carbonate / Methanol / Water Mixtures Using Zeolite Membranes

Authors: Jong-Ho Moon, Dong-Ho Lee, Hyunuk Kim, Young Cheol Park, Jong-Seop Lee, Jae-deok Jeon, Hyung-Keun Lee

Abstract:

A novel membrane reactor process for DMC synthesis from carbon dioxide has been developing in Korea Institute of Energy Research. The scheme of direct synthesis of DMC from CO₂ and Methanol is 'CO₂ + 2MeOH ↔ DMC + H₂O'. Among them, reactants are CO₂ and MeOH, product is DMC, and byproduct is H₂O (water). According to Le Chatelier’s principle, removing byproduct (water) can shift the reaction equilibrium to the right (DMC production). The main purpose of this process is removing water during the reaction. For efficient in situ water removal (dehydration) and DMC separation, zeolite 4A membranes with very small pore diameter and hydrophilicity were introduced. In this study, pervaporation performances of binary and ternary DMC / methanol / water mixtures were evaluated.

Keywords: dimehtyl carbonate, methanol, water, zeolite membrane, pervaporation

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2243 Quantization of Damped Systems Based on the Doubling of Degrees of Freedom

Authors: Khaled I. Nawafleh

Abstract:

In this paper, it provide the canonical approach for studying dissipated oscillators based on the doubling of degrees of freedom. Clearly, expressions for Lagrangians of the elementary modes of the system are given, which ends with the familiar classical equations of motion for the dissipative oscillator. The equation for one variable is the time reversed of the motion of the second variable. it discuss in detail the extended Bateman Lagrangian specifically for a dual extended damped oscillator time-dependent. A Hamilton-Jacobi analysis showing the equivalence with the Lagrangian approach is also obtained. For that purpose, the techniques of separation of variables were applied, and the quantization process was achieved.

Keywords: doubling of degrees of freedom, dissipated harmonic oscillator, Hamilton-Jacobi, time-dependent lagrangians, quantization

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2242 Board Structure, Composition, and Firm Performance: A Theoretical and Empirical Review

Authors: Suleiman Ahmed Badayi

Abstract:

Corporate governance literature is very wide and involves several empirical studies conducted on the relationship between board structure, composition and firm performance. The separation of ownership and control in organizations were aimed at reducing the losses suffered by the investors in the event of financial scandals. This paper reviewed the theoretical and empirical literature on the relationship between board composition and its impact on firm performance. The findings from the studies provide different results while some are of the view that board structure is related to firm performance, many empirical studies indicates no relationship. However, others found a U-shape relationship between firm performance and board structure. Therefore, this study argued that board structure is not much significant to determine the financial performance of a firm.

Keywords: board structure, composition, firm performance, corporate governance

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2241 Technical Option Brought Solution for Safe Waste Water Management in Urban Public Toilet and Improved Ground Water Table

Authors: Chandan Kumar

Abstract:

Background and Context: Population growth and rapid urbanization resulted nearly 2 Lacs migrants along with families moving to Delhi each year in search of jobs. Most of these poor migrant families end up living in slums and constitute an estimated population of 1.87 lacs every year. Further, more than half (52 per cent) of Delhi’s population resides in places such as unauthorized and resettled colonies. Slum population is fully dependent on public toilet to defecate. In Public toilets, manholes either connected with Sewer line or septic tank. Septic tank connected public toilet faces major challenges to dispose of waste water. They have to dispose of waste water in outside open drain and waste water struck out side of public toilet complex and near to the slum area. As a result, outbreak diseases such as Malaria, Dengue and Chikungunya in slum area due to stagnated waste water. Intervention and Innovation took place by Save the Children in 21 Public Toilet Complexes of South Delhi and North Delhi. These public toilet complexes were facing same waste water disposal problem. They were disposing of minimum 1800 liters waste water every day in open drain. Which caused stagnated water-borne diseases among the nearest community. Construction of Soak Well: Construction of soak well in urban context was an innovative approach to minimizing the problem of waste water management and increased water table of existing borewell in toilet complex. This technique made solution in Ground water recharging system, and additional water was utilized in vegetable gardening within the complex premises. Soak well had constructed with multiple filter media with inlet and safeguarding bed on surrounding surface. After construction, soak well started exhausting 2000 liters of waste water to raise ground water level through different filter media. Finally, we brought a change in the communities by constructing soak well and with zero maintenance system. These Public Toilet Complexes were empowered by safe disposing waste water mechanism and reduced stagnated water-borne diseases.

Keywords: diseases, ground water recharging system, soak well, toilet complex, waste water

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2240 Aeroelastic Stability Analysis in Turbomachinery Using Reduced Order Aeroelastic Model Tool

Authors: Chandra Shekhar Prasad, Ludek Pesek Prasad

Abstract:

In the present day fan blade of aero engine, turboprop propellers, gas turbine or steam turbine low-pressure blades are getting bigger, lighter and thus, become more flexible. Therefore, flutter, forced blade response and vibration related failure of the high aspect ratio blade are of main concern for the designers, thus need to be address properly in order to achieve successful component design. At the preliminary design stage large number of design iteration is need to achieve the utter free safe design. Most of the numerical method used for aeroelastic analysis is based on field-based methods such as finite difference method, finite element method, finite volume method or coupled. These numerical schemes are used to solve the coupled fluid Flow-Structural equation based on full Naiver-Stokes (NS) along with structural mechanics’ equations. These type of schemes provides very accurate results if modeled properly, however, they are computationally very expensive and need large computing recourse along with good personal expertise. Therefore, it is not the first choice for aeroelastic analysis during preliminary design phase. A reduced order aeroelastic model (ROAM) with acceptable accuracy and fast execution is more demanded at this stage. Similar ROAM are being used by other researchers for aeroelastic and force response analysis of turbomachinery. In the present paper new medium fidelity ROAM is successfully developed and implemented in numerical tool to simulated the aeroelastic stability phenomena in turbomachinery and well as flexible wings. In the present, a hybrid flow solver based on 3D viscous-inviscid coupled 3D panel method (PM) and 3d discrete vortex particle method (DVM) is developed, viscous parameters are estimated using boundary layer(BL) approach. This method can simulate flow separation and is a good compromise between accuracy and speed compared to CFD. In the second phase of the research work, the flow solver (PM) will be coupled with ROM non-linear beam element method (BEM) based FEM structural solver (with multibody capabilities) to perform the complete aeroelastic simulation of a steam turbine bladed disk, propellers, fan blades, aircraft wing etc. The partitioned based coupling approach is used for fluid-structure interaction (FSI). The numerical results are compared with experimental data for different test cases and for the blade cascade test case, experimental data is obtained from in-house lab experiments at IT CAS. Furthermore, the results from the new aeroelastic model will be compared with classical CFD-CSD based aeroelastic models. The proposed methodology for the aeroelastic stability analysis of gas turbine or steam turbine blades, or propellers or fan blades will provide researchers and engineers a fast, cost-effective and efficient tool for aeroelastic (classical flutter) analysis for different design at preliminary design stage where large numbers of design iteration are required in short time frame.

Keywords: aeroelasticity, beam element method (BEM), discrete vortex particle method (DVM), classical flutter, fluid-structure interaction (FSI), panel method, reduce order aeroelastic model (ROAM), turbomachinery, viscous-inviscid coupling

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2239 A Plasmonic Mass Spectrometry Approach for Detection of Small Nutrients and Toxins

Authors: Haiyang Su, Kun Qian

Abstract:

We developed a novel plasmonic matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) approach to detect small nutrients and toxin in complex biological emulsion samples. We used silver nanoshells (SiO₂@Ag) with optimized structures as matrices and achieved direct analysis of ~6 nL of human breast milk without any enrichment or separation. We performed identification and quantitation of small nutrients and toxins with limit-of-detection down to 0.4 pmol (for melamine) and reaction time shortened to minutes, superior to the conventional biochemical methods currently in use. Our approach contributed to the near-future application of MALDI MS in a broad field and personalized design of plasmonic materials for real case bio-analysis.

Keywords: plasmonic materials, laser desorption/ionization, mass spectrometry, small nutrients, toxins

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2238 Secular Ethics from the Viewpoint of Mostafa Malekian (Analyze, Review, and Critique)

Authors: Hamideh Rahmani

Abstract:

The subject matter of ethics is being changed in modern life, which had been an issue for a long time and aimed to define its moral boundaries in human's intellectual and everyday life. This has led to the introduction of notions based on the separation of religion from ethics in recent decades. It is in conflict with the traditional view, which introduces ethics as raised from religion and religion as the most crucial credit for ethics. The purpose of this study is to investigate the elements of secular ethics from the perspective of Mostafa Malekian, seeking to achieve his notions. After examining the strengths of secular ethics parameters from the viewpoint of Malekian, this research found his ethics in his interpretation of the ideal life which he treats as ethics, got a very strong link with his secularist project known as rationality and spirituality. We will analyze, review, and critique his ethics in the following.

Keywords: secular ethics, Mostafa Malakian, global ethics, rationality, spirituality

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2237 Artificial Intelligence Ethics: What Business Leaders Need to Consider for the Future

Authors: Kylie Leonard

Abstract:

Investment in artificial intelligence (AI) can be an attractive opportunity for business leaders as there are many easy-to-see benefits. These benefits include task completion rates, overall cost, and better forecasting. Business leaders are often unaware of the challenges that can accompany AI, such as data center costs, access to data, employee acceptance, and privacy concerns. In addition to the benefits and challenges of AI, it is important to practice AI ethics to ensure the safe creation of AI. AI ethics include aspects of algorithm bias, limits in transparency, and surveillance. To be a good business leader, it is critical to address all the considerations involving the challenges of AI and AI ethics.

Keywords: artificial intelligence, artificial intelligence ethics, business leaders, business concerns

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2236 Virtual Reality for Chemical Engineering Unit Operations

Authors: Swee Kun Yap, Sachin Jangam, Suraj Vasudevan

Abstract:

Experiential learning is dubbed as a highly effective way to enhance learning. Virtual reality (VR) is thus a helpful tool in providing a safe, memorable, and interactive learning environment. A class of 49 fluid mechanics students participated in starting up a pump, one of the most used equipment in the chemical industry, in VR. They experience the process in VR to familiarize themselves with the safety training and the standard operating procedure (SOP) in guided mode. Students subsequently observe their peers (in groups of 4 to 5) complete the same training. The training first brings each user through the personal protection equipment (PPE) selection, before guiding the user through a series of steps for pump startup. One of the most common feedback given by industries include the weakness of our graduates in pump design and operation. Traditional fluid mechanics is a highly theoretical module loaded with engineering equations, providing limited opportunity for visualization and operation. With VR pump, students can now learn to startup, shutdown, troubleshoot and observe the intricacies of a centrifugal pump in a safe and controlled environment, thereby bridging the gap between theory and practical application. Following the completion of the guided mode operation, students then individually complete the VR assessment for pump startup on the same day, which requires students to complete the same series of steps, without any cues given in VR to test their recollection rate. While most students miss out a few minor steps such as the checking of lubrication oil and the closing of minor drain valves before pump priming, all the students scored full marks in the PPE selection, and over 80% of the students were able to complete all the critical steps that are required to startup a pump safely. The students were subsequently tested for their recollection rate by means of an online quiz 3 weeks later, and it is again found that over 80% of the students were able to complete the critical steps in the correct order. In the survey conducted, students reported that the VR experience has been enjoyable and enriching, and 79.5% of the students voted to include VR as a positive supplementary exercise in addition to traditional teaching methods. One of the more notable feedback is the higher ease of noticing and learning from mistakes as an observer rather than as a VR participant. Thus, the cycling between being a VR participant and an observer has helped tremendously in their knowledge retention. This reinforces the positive impact VR has on learning.

Keywords: experiential learning, learning by doing, pump, unit operations, virtual reality

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2235 Experimental and Numerical Investigation of Flow Control Using a Novel Active Slat

Authors: Basman Elhadidi, Islam Elqatary, Osama Saaid, Hesham Othman

Abstract:

An active slat is developed to increase the lift and delay the separation for a DU96-W180 airfoil. The active slat is a fixed slat that can be closed, fully opened or intermittently opened by a rotating vane depending on the need. Experimental results show that the active slat has reduced the mean pressure and increased the mean velocity on the suction side of the airfoil for all positive angles of attack, indicating an increase of lift. The experimental data and numerical simulations also show that the direction of actuator vane rotation can influence the mixing of the flow streams on the suction side and hence influence the aerodynamic performance.

Keywords: active slat, flow control, experimental investigation, aerodynamic performance

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2234 The Study of Effect the Number of Cluster in the Branch on Vegetative Characteristics of Pistacia vera

Authors: Seyeh Hassan Eftekhar Afzali, Hamid Mohammadi

Abstract:

Pistachio is like almond but the second cycle of growth (third phase) has rather fast growth. This is caused to add final mass of product. When the germ grows, it and its cover are reached to the final size during six week period. As starting the second phase, the lignifications of pericarp is begun and continued for 4 or 6 weeks. Physiological maturity or easy separation of green from scutum is specified. This test was done according to random blocks of 6 orchards in the type of Ahmad Aghaie with 4 iterations. Vegetative properties of branch are investigated. The results of the bunch numbers on the growth of branch in current year are shown that the most growth of branch is happened by trimming of one and two bunches of the branch and the most diameter of the branch is happened by trimming of one to four bunches of branch. Trimming of a bunch is caused the most number of pistachio products in the bunch.

Keywords: pistachio, cluster, bud, fruit, branch

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2233 Intimate Femicide–Suicide in Israel: The Role of Migration and the Context

Authors: Revital Sela-Shayovitz

Abstract:

The current study examined the nature, the characteristics and the extent of intimate femicide followed by suicide (femicide-suicide) in Israel between the years 2005 – 2014. Data were collected from the Israeli organization ‘No to Violence Against Women’ and from two daily and widely-read newspapers in Israel. The findings indicated that migration is a risk factor for intimate femicide-suicide: the majority of the cases occurred among immigrants (59%). Moreover, the vulnerability of Ethiopian immigrants is very high in comparison to the other groups in Israeli society. The dominant motives were the victim's desire for separation and arguments between partners. The main methods used were firearms and stabbing followed by hanging. Furthermore, a prior report about violence was documented in 37% of the cases. The paper discusses these findings in the context of the existing research, offers directions for future research, and suggests some response strategies.

Keywords: ethnicity, immigrants, intimate femicide, suicide

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2232 Description of Geotechnical Properties of Jabal Omar

Authors: Ibrahim Abdel Gadir Malik, Dafalla Siddig Dafalla, Osama Abdelgadir El-Bushra

Abstract:

Geological and engineering characteristics of intact rock and the discontinuity surfaces was used to describe and classify rock mass into zones based on mechanical and physical properties. Many conditions terms that affect the rock mas; such as Rock strength, Rock Quality Designation (RQD) value, joint spacing, and condition of joint, water condition with block size, joint roughness, separation, joint hardness, friction angle and weathering were used to classify the rock mass into: Good quality (class II) (RMR values range between 75% and 56%), Good to fair quality (class II to III) (RMR values range between 70% and 55%), Fair quality (class III) (RMR values range between 60% and 50%) and Fair to poor quality (Class III to IV) (RMR values, range between (50% and 35%).

Keywords: rock strength, RQD, joints, weathering

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2231 Randomized Controlled Trial of Ultrasound Guided Bilateral Intermediate Cervical Plexus Block in Thyroid Surgery

Authors: Neerja Bharti, Drishya P.

Abstract:

Introduction: Thyroidectomies are extensive surgeries involving a significant degree of tissue handling and dissection and are associated with considerable postoperative pain. Regional anaesthesia techniques have immerged as possible inexpensive and safe alternatives to opioids in the management of pain after thyroidectomy. The front of the neck is innervated by branches from the cervical plexus, and hence, several approaches for superficial and deep cervical plexus block (CPB) have been described to provide postoperative analgesia after neck surgery. However, very few studies have explored the analgesic efficacy of intermediate CPB for thyroid surgery. In this study, we have evaluated the effects of ultrasound-guided bilateral intermediate CPB on perioperative opioid consumption in patients undergoing thyroidectomy under general anesthesia. Methods: In this prospective randomized controlled study, fifty ASA grade I-II adult patients undergoing thyroidectomy were randomly divided into two groups: the study group received ultrasound-guided bilateral intermediate CPB with 10 ml 0.5% ropivacaine on each side, while the control group received the same block with 10 ml normal saline on each side just after induction of anesthesia. Anesthesia was induced with propofol, fentanyl, and vecuronium and maintained with propofol infusion titrated to maintain the BIS between 40 and 60. During the postoperative period, rescue analgesia was provided with PCA fentanyl, and the pain scores, total fentanyl consumption, and incidence of nausea and vomiting during 24 hours were recorded, and overall patient satisfaction was assessed. Results: The groups were well-matched with respect to age, gender, BMI, and duration of surgery. The difference in intraoperative propofol and fentanyl consumption was not statistically significant between groups. However, the intraoperative haemodynamic parameters were better maintained in the study group than in the control group. The postoperative pain scores, as measured by VAS at rest and during movement, were lower, and the total fentanyl consumption during 24 hours was significantly less in the study group as compared to the control group. Patients in the study group reported better satisfaction scores than those in the control group. No adverse effects of ultrasound-guided intermediate CPB block were reported. Conclusion: We concluded that ultrasound-guided intermediate cervical plexus block is a safe and effective method for providing perioperative analgesia during thyroid surgery.

Keywords: thyroidectomy, cervical plexus block, pain relief, opioid consumption

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2230 A Study of Issues and Mitigations on Distributed Denial of Service and Medical Internet of Things Devices

Authors: Robin Singh, Jing-Chiou Liou

Abstract:

The Internet of Things (IoT) devices are being used heavily as part of our everyday routines. Through improved communication and automated procedures, its popularity has assisted users in raising the quality of work. These devices are used in healthcare in order to better collect the patient’s data for their treatment. They are generally considered safe and secure. However, there is some possibility that some loopholes do exist which manufacturers do need to identify before some hacker takes advantage of them. For this study, we focused on two medical IoT devices which are pacemakers and hearing aids. The aim of this paper is to identify if there is any likelihood of these medical devices being hijacked and used as a botnet in Distributed Denial-Of Service attacks. Moreover, some mitigation strategies are being proposed to better secure

Keywords: cybersecurity, DDoS, IoT, medical devices

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2229 End-of-Life Vehicle Framework in Bumper Development Process

Authors: Majid Davoodi Makinejad, Reza Ghaeli

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Developing sustainable and environment-friendly products has become a major concern in the car manufacturing industry. New legislation ‘End of Life Vehicle’ increased design complexities of bumper system parameters e.g. design for disassembly, design for remanufacturing and recycling. ELV processing employs dismantling, shredding and landfill. The bumper is designed to prevent physical damage, reduce aerodynamic drag force as well as being aesthetically pleasing to the consumer. Design for dismantling is the first step in ELVs approach in the bumper system. This study focused on the analysis of ELV value in redesign solutions of the bumper system in comparison with the conventional concept. It provided a guideline to address the critical consideration in material, manufacturing and joining methods of bumper components to take advantages in easy dismounting, separation and recycling.

Keywords: sustainable development, environmental friendly, bumper system, end of life vehicle

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2228 Ficus carica as Adsorbent for Removal of Phenol from Aqueous Solutions: Modeling and Optimization

Authors: Tizi Hayet, Berrama Tarek, Bounif Nadia

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Phenol and its derivatives are organic compounds utilized in the chemical industry. They are introduced into the environment by accidental spills and the illegal release of industrial and municipal wastewater. Phenols are organic intermediaries that are considered potential pollutants. Adsorption is one of the purification and separation techniques used in this area. Algeria annually produces 131000 tons of fig; therefore, a large amount of fig leaves is generated, and the conversion of this waste into adsorbent allows the valorization of agricultural residue. The main purpose of this present work is to describe an application of a statistical method for modeling and to optimize the conditions of the phenol adsorption from agricultural by-products, locally available (fig leaves). The best experimental performance of phenol elimination on the adsorbent was obtained with: Adsorbent concentration (X₂) = 200 mg L⁻¹; Initial concentration (X₃) = 150 mg L⁻¹; Speed agitation (X₁) = 300 rpm.

Keywords: low-cost adsorbents, adsorption, fig leaves, phenol, factorial design

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2227 Extract and Naphthoquinone Derivatives from in vitro Culture of an Ascomycetous Marine Fungus with Antibacterial Activity

Authors: Uftah Ali M. Shushni, Viola Stuppec, Ulrike Lindequist

Abstract:

Because of the evolving resistance of microorganisms to existing antibiotics, there is an increasing need for new antibiotics not only in human but also in veterinary medicine. As part of our ongoing work on the secondary metabolites produced by marine fungi, the organic extract of the culture filtrate of an Ascomycetous fungus, which was found on driftwood collected from the coast of the Greifswalder Bodden, Baltic Sea, Germany displayed antimicrobial activity against some fish and human pathogenic bacteria. Bioactivity-guided column chromatographic separation led to the isolation of 6-Deoxybostrycoidin. The structure was determined from the interpretation of spectroscopic data (UV, MS, and NMR). 6-Deoxybostrycoidin exhibited in vitro activity against Bacillus subtilis, Staphylococcus aureus and Flexibacter maritimus with minimal inhibitory concentrations of 25, 12.5 and 12.5 μg/ml respectively.

Keywords: marine fungi, fish pathogenic bacteria, microorganism, medicine

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2226 Hydrogen Production Using Solar Energy

Authors: I. M. Sakr, Ali M. Abdelsalam, K. A. Ibrahim, W. A. El-Askary

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This paper presents an experimental study for hydrogen production using alkaline water electrolysis operated by solar energy. Two methods are used and compared for separation between the cathode and anode, which are acrylic separator and polymeric membrane. Further, the effects of electrolyte concentration, solar insolation, and space between the pair of electrodes on the amount of hydrogen produced and consequently on the overall electrolysis efficiency are investigated. It is found that the rate of hydrogen production increases using the polymeric membrane installed between the electrodes. The experimental results show also that, the performance of alkaline water electrolysis unit is dominated by the electrolyte concentration and the gap between the electrodes. Smaller gaps between the pair of electrodes are demonstrated to produce higher rates of hydrogen with higher system efficiency.

Keywords: hydrogen production, water electrolysis, solar energy, concentration

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2225 Pre-Shared Key Distribution Algorithms' Attacks for Body Area Networks: A Survey

Authors: Priti Kumari, Tricha Anjali

Abstract:

Body Area Networks (BANs) have emerged as the most promising technology for pervasive health care applications. Since they facilitate communication of very sensitive health data, information leakage in such networks can put human life at risk, and hence security inside BANs is a critical issue. Safe distribution and periodic refreshment of cryptographic keys are needed to ensure the highest level of security. In this paper, we focus on the key distribution techniques and how they are categorized for BAN. The state-of-art pre-shared key distribution algorithms are surveyed. Possible attacks on algorithms are demonstrated with examples.

Keywords: attacks, body area network, key distribution, key refreshment, pre-shared keys

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2224 Experimental and Numerical Investigation of Flow Control Using a Novel Active Slat

Authors: Basman Elhadidi, Islam Elqatary, Osama Mohamady, Hesham Othman

Abstract:

An active slat is developed to increase the lift and delay the separation for a DU96-W180 airfoil. The active slat is a fixed slat that can be closed, fully opened or intermittently opened by a rotating vane depending on the need. Experimental results show that the active slat has reduced the mean pressure and increased the mean velocity on the suction side of the airfoil for all positive angles of attack, indicating an increase of lift. The experimental data and numerical simulations also show that the direction of actuator vane rotation can influence the mixing of the flow streams on the suction side and hence influence the aerodynamic performance.

Keywords: active slat, flow control, DU96-W180 airfoil, flow streams

Procedia PDF Downloads 375
2223 Ficus Carica as Adsorbent for Removal of Phenol from Aqueous Solutions: Modelling and Optimization

Authors: Tizi Hayet, Berrama Tarek, Bounif Nadia

Abstract:

Phenol and its derivatives are organic compounds utilized in the chemical industry. They are introduced into the environment by accidental spills and illegal release of industrial and municipal wastewater. Phenols are organic intermediaries that considered as potential pollutants. Adsorption is one of the purification and separation techniques used in this area. Algeria produces annually 131000 tones of fig; therefore, a large amount of fig leaves is generated, and the conversion of this waste into adsorbent allows the valorization of agricultural residue. The main purpose of this present work is to describe an application of the statistical method for modeling and optimization of the conditions of the phenol (Ph) adsorption from agricultural by-product locally available (fig leaves). The best experimental performance of Ph elimination on the adsorbent was obtained with: Adsorbent concentration (X2) = 0.2 g L-1; Initial concentration (X3) = 150 mg L-1; Speed agitation (X1) = 300 rpm.

Keywords: low-cost adsorbents, fig leaves, full factorial design, phenol, biosorption

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2222 Translingual Discrimination and Migrants

Authors: Sender Dovchin

Abstract:

Moving beyond two main frameworks of interlingual and intralingual discrimination, this paper will address the understanding of translingual discrimination. This concept refers to discrimination based on how one uses certain languages, linguistic and communicative repertoires, which are (il)legitimised by the interactants. Translingual discrimination contributes intensity to transnational migrations processes, where migrants with transitional backgrounds seem to illustrate two main characteristics of marginalizations – “name discrimination” and “accentism”. The lifelong accumulation of these characteristics of translingual discrimination may cause negative emotionality, such as translingual inferiority complexes, to its victims. As a result, these transnational migrants seem to adopt varied coping strategies such as CV-whitening and accent purifications while probing for translingual safe spaces. The presentation concludes with the socio-cultural and pedagogical implications of translingual discrimination in relation to the language usage of transnational migrants.

Keywords: accentism, discrimination, migrants, translingualism

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2221 Studies on Separation of Scandium from Sulfate Environment Using Ion Exchange Technique

Authors: H. Hajmohammadi , A. H. Jafari, M. Eskandari Nasab

Abstract:

The ion exchange method was used to assess the absorption of sulfate media from laboratory-grade materials. The Taguchi method was employed for determining the optimum conditions for scandium adsorption. Results show that optimum conditions for scandium adsorption from sulfate were obtained by Purolite C100 cationic resin in 0.1 g/l sulfuric acid and scandium concentration of 2 g/l at 25 °C. Studies also showed that lowering H₂SO₄ concentration and aqueous phase temperature leads to an increase in Sc adsorption. Visual Minteq software was used to ascertain the various possible cation types and the effect of concentration of scandium ion species on scandium adsorption by cationic resins. The simulation results of the above software show that scandium ion species are often cationic species that are consistent with experimental data.

Keywords: scandium, ion exchange resin, simulation, leach copper

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2220 Towards an Understanding of Breaking and Coalescence Process in Bitumen Emulsions

Authors: Abdullah Khan, Per Redelius, Nicole Kringos

Abstract:

The breaking and coalescence process in bitumen emulsion strongly influence the performance of the cold mix asphalt (CMA) and this phase separation process is affected by the physio-chemical changes happening at the bitumen/water interface. In this paper, coalescence experiments of two bitumen droplets in an emulsion environment have been carried out by a newly developed test procedure. In this study, different types of emulsifiers were selected to understand the coalescence process with respect to changes in the water phase surface tension due to addition of different surfactants and other additives such as salts. The research showed that the relaxation kinetics of bitumen droplets varied with the type of emulsifier, its concentration as well as with and without presence of salt in the water phase. Moreover, kinetics of the coalescence process was also investigated with the temperature variation.

Keywords: bitumen emulsions, breaking and coalescence, cold mix asphalt, emulsifiers, relaxation, salts

Procedia PDF Downloads 336
2219 Method Development and Validation for Quantification of Active Content and Impurities of Clodinafop Propargyl and Its Enantiomeric Separation by High-Performance Liquid Chromatography

Authors: Kamlesh Vishwakarma, Bipul Behari Saha, Sunilkumar Sing, Abhishek Mishra, Sreenivas Rao

Abstract:

A rapid, sensitive and inexpensive method has been developed for complete analysis of Clodinafop Propargyl. Clodinafop Propargyl enantiomers were separated on chiral column, Chiral Pak AS-H (250 mm. 4.6mm x 5µm) with mobile phase n-hexane: IPA (96:4) at flow rate 1.5 ml/min. The effluent was monitored by UV detector at 230 nm. Clodinafop Propagyl content and impurity quantification was done with reverse phase HPLC. The present study describes a HPLC method using simple mobile phase for the quantification of Clodinafop Propargyl and its impurities. The method was validated and found to be accurate, precise, convenient and effective. Moreover, the lower solvent consumption along with short analytical run time led to a cost effective analytical method.

Keywords: Clodinafop Propargyl, method, validation, HPLC-UV

Procedia PDF Downloads 369