Search results for: plate-stiffener combination and hard corner

Authors: Bunjirtluk Jintaridth

Abstract:

Utilization of silicon for sustainable rice cultivation in acid sulfate soils was studied for 2 years. The study was conducted on Rungsit soils in Amphoe Tanyaburi, Pathumtani Province. The objectives of this study were to assess the effect of high quality organic fertilizer in combination with silicon and chemical fertilizer on rice yield, chemical soil properties after using soil amendments, and also to assess the economic return. A Randomized Complete Block Design (RCBD) with 10 treatments and 3 replications were employed. The treatments were as follows: 1) control 2) chemical fertilizer (recommended by Land Development Department, LDD 3) silicon 312 kg/ha 4) high quality organic fertilizer at 1875 kg/ha (the recommendation rate by LDD) 5) silicon 156 kg/ha in combination with high quality organic fertilizer 1875 kg/ha 6) silicon at the 312 kg/ha in combination with high quality organic fertilizer 1875 kg/ha 7) silicon 156 kg/ha in combination with chemical fertilizer 8) silicon at the 312 kg/ha in combination with chemical fertilizer 9) silicon 156 kg/ha in combination with ½ chemical fertilizer rate, and 10) silicon 312 kg/ha in combination with ½ chemical fertilizer rate. The results of 2 years indicated the treatment tended to increase soil pH (from 5.1 to 4.7-5.5), percentage of organic matter (from 2.43 to 2.54 - 2.94%); avail. P (from 7.5 to 7-21 mg kg-1 P; ext. K (from 616 to 451-572 mg kg-1 K), ext Ca (from 1962 to 2042.3-4339.7 mg kg-1 Ca); ext Mg (from 1586 to 808.7-900 mg kg-1 Mg); but decrease the ext. Al (from 2.56 to 0.89-2.54 cmol kg-1 Al. Two years average of rice yield, the highest yield was obtained from silicon 156 kg/ha application in combination with high quality organic fertilizer 300 kg/rai (3770 kg/ha), or using silicon at the 312 kg/ha combination with high quality organic fertilizer 300 kg/rai. (3,750 kg/ha). It was noted that chemical fertilizer application with 156 and 312 kg/ha silicon gave only 3,260 และ 3,133 kg/ha, respectively. On the other hand, half rate of chemical fertilizer with 156 and 312 kg/ha with silicon gave the yield of 2,934 และ 3,218 kg/ha, respectively. While high quality organic fertilizer only can produce 3,318 kg/ha as compare to rice yield of 2,812 kg/ha from control. It was noted that the highest economic return was obtained from chemical fertilizer treated plots (886 dollars/ha). Silicon application at the rate of 156 kg/ha in combination with high quality organic fertilizer 1875 kg/ha gave the economic return of 846 dollars/ha, while 312 kg/ha of silicon with chemical fertilizer gave the lowest economic return (697 dollars/ha).

Keywords: rice, high quality organic fertilizer, acid sulfate soil, silicon

Procedia PDF Downloads 130

Authors: Theodore Grosch, Felipe Koji Godinho Hoshino

Abstract:

In wireless communications, 3GPP LTE is one of the solutions to meet the greater transmission data rate demand. One issue inherent to this technology is the PAPR (Peak-to-Average Power Ratio) of OFDM (Orthogonal Frequency Division Multiplexing) modulation. This high PAPR affects the efficiency of power amplifiers. One approach to mitigate this effect is the Crest Factor Reduction (CFR) technique. In this work, we simulate the impact of Hard Limited Clipping Crest Factor Reduction technique on BER (Bit Error Rate) in OFDM based Systems. In general, the results showed that CFR has more effects on higher digital modulation schemes, as expected. More importantly, we show the worst-case degradation due to CFR on QPSK, 16QAM, and 64QAM signals in a linear system. For example, hard clipping of 9 dB results in a 2 dB increase in signal to noise energy at a 1% BER for 64-QAM modulation.

Keywords: bit error rate, crest factor reduction, OFDM, physical layer simulation

Procedia PDF Downloads 338

Authors: Kedar S. Prabhavalkar, Nimmy Baby Poovanpallil

Abstract:

Lamotrigine is approved for maintenance treatment of bipolar I disorder. However, its role in the treatment of acute bipolar depression is not well clear. Its efficacy in the treatment of major depressive disorders including refractory unipolar depression suggested the use of lamotrigine as an augmentation drug for acute bipolar depression. The present study aims to evaluate and perform a comparative analysis of the therapeutic effects of lamotrigine, an epileptic mood stabilizer, when used alone and in combination with duloxetine in treating acute bipolar depression at different doses of lamotrigine. Male swiss albino mice were used. For evaluation of efficacy of combination, immobility period was analyzed 30 min after the treatment from forced swim and tail suspension tests. Further amount of sucrose consumed in sucrose preference test was estimated. The combination of duloxetine and lamotrigine showed potentiation of antidepressant activity in acute models. Decrease in immobility time and increase in the amount of sucrose consumption in stressed mice were higher in combined group compared to lamotrigine monotherapy group. Brain monoamine levels were also attenuated more with combination compared to monotherapy. Results of the present study suggest potential role of lamotrigine and duloxetine combination in the treatment of acute bipolar depression.

Keywords: lamotrigine, duloxetine, acute bipolar depression, augmentation

Procedia PDF Downloads 472

Authors: David Ryan, Martin Breugst, Turlough Downes, Peter A. Byrne, Gerard P. McGlacken

Abstract:

An ambident nucleophile is a nucleophile that possesses two or more distinct nucleophilic sites that are linked through resonance and are effectively “in competition” for reaction with an electrophile. Examples include enolates, pyridone anions, and nitrite anions, among many others. Reactions of ambident nucleophiles and electrophiles are extremely prevalent at all levels of organic synthesis. The principle of hard and soft acids and bases (the “HSAB principle”) is most commonly cited in the explanation of selectivities in such reactions. Although this rationale is pervasive in any discussion on ambident reactivity, the HSAB principle has received considerable criticism. As a result, the principle’s supplantation has become an area of active interest in recent years. This project focuses on developing a model for rationalizing ambident reactivity. Presented here is an approach that incorporates computational calculations and experimental kinetic data to construct Gibbs energy profile diagrams. The preferred site of alkylation of nitrite anion with a range of ‘hard’ and ‘soft’ alkylating agents was established by ¹H NMR spectroscopy. Pseudo-first-order rate constants were measured directly by ¹H NMR reaction monitoring, and the corresponding second-order constants and Gibbs energies of activation were derived. These, in combination with computationally derived standard Gibbs energies of reaction, were sufficient to construct Gibbs energy wells. By representing the ambident system as a series of overlapping Gibbs energy wells, a more intuitive picture of ambident reactivity emerges. Here, previously unexplained switches in reactivity in reactions involving closely related electrophiles are elucidated.

Keywords: ambident, Gibbs, nucleophile, rates

Procedia PDF Downloads 56

Authors: Cheniti Khalissa, Dekhili Mohamed

Abstract:

Several fungal diseases may infect hard and soft wheat, which directly affect the yield and thus the economy of the homeland. So, a treatment fungicide is one of means of diseases control. In this context, we studied two varieties of wheat; Waha for soft wheat and Hidhab for hard wheat, at the level of the Technical Institute of crops (ITGC) in the wilaya of Setif under semi-arid conditions. This study consists of a successive application of three fungicides (Tilt, Artea, and Armistarxtra) according to three treatments (T1, T2, and T3) in addition to the witness (T0) at different stages of plant development (respectively, Montaison, earing and after flowering) whose purpose is to test and determine the effectiveness of these products used sequentially. The study showed good efficacy when we use the sum of these pesticides The comparison between these different treatments indicates that the T3 treatment reduced yield losses significantly; which is evident in the main yield components such as fertility, grain yield and weight of 1000 grains. The various components of yield and final yield are all parameters to be taken into account in such a study. In general, the fungal treatment is an effective way of improving profitability. In general, the fungal treatment is an effective way of improving profitability and positioning interventions in time is one of the requirements for an appreciable efficiency.

Keywords: hard wheat, soft wheat, diseases, fungicide treatment, fertility, 1000-grain weight, semi-arid zone

Procedia PDF Downloads 374

Authors: Yanhua Ma, Lu Zhai, Xinchen Wang, Hongyu Liang

Abstract:

In this paper, by understanding the development status of the human-machine interface in today's automobile cab, a subjective and objective evaluation system for evaluating the optimization of human-machine interface matching in automobile cab was established. The man-machine interface of the car cab was divided into a software interface and a hard interface. Objective evaluation method of software human factor analysis is used to evaluate the hard interface matching; The analytic hierarchy process is used to establish the evaluation index system for the software interface matching optimization, and the multi-level fuzzy comprehensive evaluation method is used to evaluate hard interface machine. This article takes Dongfeng Sokon (DFSK) C37 model automobile as an example. The evaluation method given in the paper is used to carry out relevant analysis and evaluation, and corresponding optimization suggestions are given, which have certain reference value for designers.

Keywords: analytic hierarchy process, fuzzy comprehension evaluation method, human-machine interface, matching optimization, software human factor analysis

Procedia PDF Downloads 113

Authors: Gesti Prastiti, Maylina Adani, Yuyun darma A. N., M. Khilmi F., Yunita Wahyu Pratiwi

Abstract:

Combination therapy may allow interaction on two drugs or more that can give adverse effects on patients. Simvastatin is a drug of antihyperlipidemia it can interact with drugs which work on cytochrome P450 CYP3A4 because it can interfere the performance of simvastatin. Flavonoid found in plants can inhibit the cytochrome P450 CYP3A4 if taken with simvastatin and can increase simvastatin levels in the body and increases the potential side effects of simvastatin such as myopati and rhabdomyolysis. Green tea leaves and mint are herbal medicine which has the effect of antihiperlipidemia. This study aims to determine the potential interaction of simvastatin with herbal drinks (green tea leaves and mint). This research method are experimental post-test only control design. Test subjects were divided into 5 groups: normal group, negative control group, simvastatin group, a combination of green tea group and the combination group mint leaves. The study was conducted over 32 days and total cholesterol levels were analyzed by enzymatic colorimetric test method. Results of this study is the obtainment of average value of total cholesterol in each group, the normal group (65.92 mg/dL), the negative control group the average total cholesterol test in the normal group was (69.86 mg/dL), simvastatin group (58.96 mg/dL), the combination of green tea group (58.96 mg/dL), and the combination of mint leaves (63.68 mg/dL). The conclusion is between simvastatin combination therapy with herbal drinks have the potential for pharmacodynamic interactions with a synergistic effect, antagonist, and a powerful additive, so the combination therapy are no more effective than a single administration of simvastatin therapy.

Keywords: hyperlipidemia, simvastatin, herbal drinks, green tea leaves, mint leaves, drug interactions

Procedia PDF Downloads 367

Authors: Suresh Reddi, Mathew Leslie, Vishnu S. Das

Abstract:

Sustainable design is a prominent concept across all sectors of engineering and its importance is widely recognized within the Arabian Gulf region. Despite that sustainable or soft engineering options are not widely deployed in coastal engineering projects and a preference for utilizing ‘hard engineering’ solutions remain. The concept of soft engineering lies in “working together” with the nature to manage the coastline. This approach allows hard engineering options, such as breakwaters or sea walls, to be minimized or even eliminated altogether. Hard structures provide a firm barrier to wave energy or flooding, but in doing so they often have a significant impact on the natural processes of the coastline. This may affect the area locally or impact on neighboring zones. In addition, they often have a negative environmental impact and may create a sense of disconnect between the marine environment and local users. Soft engineering options, seek to protect the coastline by working in harmony with the natural process of sediment transport/budget. They often consider new habitat creation and creating usable spaces that will increase the sense of connection with nature. Often soft engineering options, where appropriately deployed can provide a low-maintenance, aesthetically valued, natural line of coastal protection. This paper deals with an overview of the following: The widely accepted soft engineering practices across the world; How this approach has been considered by Ramboll in some recent projects in Middle East and Asia; Challenges and barriers to use in using soft engineering options in the region; Way forward towards more widespread adoption.

Keywords: coastline, hard engineering, low maintenance, soft engineering options

Procedia PDF Downloads 110

Authors: Lubomir Machuca, Vit Fara

Abstract:

Ammonium nitrate (AN) is produced by the reaction of ammonia and nitric acid, and a waste condensate is obtained. The condensate contains pure AN in concentration up to 10g/L. The salt content in the condensate is too high to discharge immediately into the river thus it must be treated. This study is concerned with the treatment of condensates from an industrial AN production by combination of electrodialysis (ED) and electrodeionization (EDI). The condensate concentration was in range 1.9–2.5g/L of AN. A pilot ED module with 25 membrane pairs following by a laboratory EDI module with 10 membrane pairs operated continuously during 800 hours. Results confirmed that the combination of ED and EDI is suitable for the condensate treatment.

Keywords: desalination, electrodialysis, electrodeionization, fertilizer industry

Procedia PDF Downloads 209

Authors: Hema Lattupalli

Abstract:

Introduction: The palate forms a partition between the oral cavity and nasal cavity. The palate is made up of two parts hard palate and soft palate. The Hard palate forms the anterior part of the palate, the soft palate forms a movable muscular fold covered by mucous membrane that is suspended from the posterior border of a hard palate. Aim and Objectives: Soft palate morphological variations have a great paucity in the literature. It’s also believed that the soft palate has no such important anatomical variations. There is a variable presentation of the soft palate morphology in the lateral cephalograms. The aim of this study is to identify the velar morphology. Materials and Methods: 100 normal subjects between the age group of 20 – 35 were taken for the study. Method: Lateral Cephalogram (radiologic study). Results: Different shapes of the soft palate were observed in the lateral cephalograms. The morphology of soft palate was classified into six types 1.Leaf like (50 cases) most common type, 2.Straight line (20 cases), 3.S shaped (4 cases) very rare, 4.Butt like (10 cases), 5. Rat tail (6 cases), 6. Hook shaped (10 cases). Conclusion: This classification helps us to understand the better diversity of the velar morphology in mid-sagittal plane. These findings help us to understand the etiology of OSAS.

Keywords: soft palate, cephalometric radiographs, morphology, cleft palate, obstructive sleep apnoea syndrome

Procedia PDF Downloads 335

Authors: M. Habibi

Abstract:

The time-resolved studies of soft and hard X-ray were carried out over a wide range of argon pressures by employing an array of eight filtered photo PIN diodes and a scintillation detector, simultaneously. In 50% of the discharges, the soft X-ray is seen to be emitted in short multiple pulses corresponding to different compression, whereas it is a single pulse for hard X-rays corresponding to only the first strong compression. It should be stated that multiple compressions dominantly occur at low pressures and high pressures are mostly in the single compression regime. In 43% of the discharges, at all pressures except for optimum pressure, the first period is characterized by two or more sharp peaks.The X–ray signal intensity during the second and subsequent compressions is much smaller than the first compression.

Keywords: plasma focus device, SXR, HXR, Pin-diode, argon plasma

Procedia PDF Downloads 381

Authors: Jenq-Shyong Chen, Ben-Fong Yu

Abstract:

CNC(computer numerical control) machining centers have been widely used for machining different metal components for various industries. For a specific CNC machine, its everyday job is assigned to cut different products with quite different attributes such as material type, workpiece weight, geometry, tooling, and cutting conditions. Theoretically, the dynamic characteristics of the CNC machine should be properly tuned match each machining job in order to get the optimal machining performance. However, most of the CNC machines are set with only a standard set of CNC parameters. In this study, we have developed an auto-tuning system which can automatically change the CNC parameters and in hence change the machine dynamic characteristics according to the selection of machining modes which are set by the mixed combination of three machine performance indexes: the HO (high surface quality) index, HP (high precision) index and HS (high speed) index. The acceleration, jerk, corner error tolerance, oscillation and dynamic bandwidth of machine’s feed axes have been changed according to the selection of the machine performance indexes. The proposed auto-tuning system of the CNC parameters has been implemented on a PC-based CNC controller and a three-axis machining center. The measured experimental result have shown the promising of our proposed auto-tuning system.

Keywords: auto-tuning, CNC parameters, machining mode, high speed, high accuracy, high surface quality

Procedia PDF Downloads 357

Authors: Ya-Ju Ju, Li-Chen Yang, Yi-Chun Du, Rong-Ju Cherng

Abstract:

Introduction: It is estimated that 5-6% of school-aged children may be diagnosed to have developmental coordination disorder (DCD). Children with DCD are characterized with motor skill difficulty which cannot be explained by any medical or intellectual reasons. Such motor difficulties limit children’s participation to sports activity, further affect their physical fitness, cardiopulmonary function and balance, and may lead to obesity. The purpose of the project was to develop an exergaming system for children with DCD aiming to improve their physical fitness, cardiopulmonary function and balance ability. Methods: This study took five steps to build up the system: system planning, tasks selection, tasks programming, system integration and usability test. The system basically adopted virtual reality technique to integrate self-developed training programs. The training programs were developed to brainstorm among team members and after literature review. The selected tasks for training in the system were a combination of fundamental movement tor skill. Results and Discussion: Based on the theory of motor development, we design the training task from easy ones to hard ones, from single tasks to dual tasks. The tasks included walking, sit to stand, jumping, kicking, weight shifting, side jumping and their combination. Preliminary study showed that the tasks presented an order of development. Further study is needed to examine its effect on motor skill and cardiovascular fitness in children with DCD.

Keywords: virtual reality, virtual reality system, developmental coordination disorder, children

Procedia PDF Downloads 85

Authors: Gülten Sadullahoğlu, Baki Altuncevahir

Abstract:

The scope of this study, to investigate the magnetic properties and microstructure of Nd₂Fe₁₄B₁ by alloying with Nd₃₃.₄Fe₆₂.₆Al₄, and heat treating it at different temperatures. The stoichiometric Nd₂Fe₁₄B hard magnetic alloy and Nd₃₃.₄Fe₆₂.₆Al₄ composition was produced by arc melting under argon atmosphere. The Nd₃₃.₄Fe₆₂.₆Al₄ alloy has added to the 2:14:1 hard magnetic alloy with 48% by weight, and melted again by arc melting. Then, it was heat treated at 600, 700 and 800˚C for 3h under vacuum. In AC magnetic susceptibility measurements, for the as-cast sample, the signals decreased sharply at 101 ˚C and 313 ˚C corresponding to the Curie temperatures of the two ferromagnetic phases in addition to Fe phase. For the sample annealed at 600 ˚C, two Curie points were observed at about 257˚C and at 313˚C. However, the phase corresponding to the Curie temperature of 101 ˚C was disappeared. According to the magnetization measurements, the saturation magnetization has the highest value of 99.8 emu/g for the sample annealed at 600 ˚C, and decreased to 57.66 and 28.6 emu/g for the samples annealed at 700˚ and 800 ˚C respectively. Heat treatment resulted in an evolution of the new phase that caused changes in magnetic properties of the alloys. In order to have a clear picture, the identification of these phases are being under the investigation by XRD and SEM–EDX analysis.

Keywords: NdFeB hard magnets, bulk magnetic materials, arc melting, Curie temperature, heat treatment

Procedia PDF Downloads 256

Authors: S. Sonkham, U. Pinsopon, W. Chatlatanagulchai

Abstract:

This paper presents a method of sliding mode control (SMC) designing and developing for the servo system in a dual-stage actuator (DSA) hard disk drive. Mathematical modelling of hard disk drive actuators is obtained, extracted from measuring frequency response of the voice-coil motor (VCM) and PZT micro-actuator separately. Matlab software tools are used for mathematical model estimation and also for controller design and simulation. A model-reference approach for tracking requirement is selected as a proposed technique. The simulation results show that performance of a model-reference SMC controller design in DSA servo control can be satisfied in the tracking error, as well as keeping the positioning of the head within the boundary of +/-5% of track width under the presence of internal and external disturbance. The overall results of model-reference SMC design in DSA are met per requirement specifications and significant reduction in %off track is found when compared to the single-state actuator (SSA).

Keywords: hard disk drive, dual-stage actuator, track following, hdd servo control, sliding mode control, model-reference, tracking control

Procedia PDF Downloads 333

Authors: Jun Ming Moey, Zhiyaun Chen, David Nicholson

Abstract:

Bad actors are often hard to detect in data that imprints their behaviour patterns because they are comparatively rare events embedded in non-bad actor data. An unsupervised machine learning framework is applied here to detect bad actors in financial crime datasets that record millions of transactions undertaken by hundreds of actors (<0.01% bad). Specifically, the framework combines ‘shallow’ (PCA, Isolation Forest) and ‘deep’ (Autoencoder) methods to detect outlier patterns. Detection performance analysis for both the individual methods and their combination is reported.

Keywords: detection, machine learning, deep learning, unsupervised, outlier analysis, data science, fraud, financial crime

Procedia PDF Downloads 66

Authors: Hanh Thi My Nguyen

Abstract:

The purpose of this research is to examine the experiences of parents of children who are deaf or hard of hearing in supporting their children to access education in Vietnam. Parents play a crucial role in supporting their children to gain full access to education. It was widely reported that parents of those children confronted a range of problems to support their children to access education. To author’s best knowledge, there has been a lack of research exploring the experiences of those parents in literature. This research examines factors affecting those parents in supporting their children to access education. To conduct the study, qualitative approach using a phenomenological research design was chosen to explore the central phenomena. Ten parents of children who were diagnosed as deaf or hard of hearing and aged 6-9 years were recruited through the support of the Association of Parents of Children with Hearing Impairment. Participants were interviewed via telephone with a mix of open and closed questions; interviews were audio recorded, transcribed and thematically analysed. The research results show that there are nine main factors that affected the parents in this study in making decisions relating to education for their children including: lack of information resources, perspectives of those parents on communication approaches, the families’ financial capacity, the psychological impact on the participants after their children’ diagnosis, the attitude of family members, attitude of school administrators, lack of local schools and qualified teachers, and current education system for the deaf in Vietnam. Apart from those factors, the lack of knowledge of the participants’ partners about deaf education and the partners’ employment are barriers to educational access and successful communication with their child.

Keywords: access to education, deaf, hard of hearing, parents experience

Procedia PDF Downloads 112

Authors: Mohamed S. El-Asfoury, Ahmed Abdel-Moneim, Mohamed N. A. Nasr

Abstract:

The current study uses finite element modeling to investigate and analyze a modified form of the from the conventional equal channel multi-angular pressing (ECMAP), using non-equal channels, on the workpiece material plastic deformation. The modified process non-equal channel multi-angular extrusion (NECMAE) is modeled using two-dimensional plane strain finite element model built using the commercial software ABAQUS. The workpiece material used is pure aluminum. The model was first validated by comparing its results to analytical solutions for single-pass equal channel angular extrusion (ECAP), as well as previously published data. After that, the model was used to examine the effects of different % of reductions of the area (for the second stage) on material plastic deformation, corner gap, and required the load. Three levels of reduction in the area were modeled; 10%, 30%, and 50%, and compared to single-pass and double-pass ECAP. Cases with a higher reduction in the area were found to have smaller corner gaps, higher and much uniform plastic deformation, as well as higher required loads. The current results are mainly attributed to the back pressure effects exerted by the second stage, as well as strain hardening effects experienced during the first stage.

Keywords: non-equal channel angular extrusion, multi-pass, sever plastic deformation, back pressure, Finite Element Modelling (FEM)

Procedia PDF Downloads 400

Authors: Rawinun Praserttaweelap, Somyot Kiatwanidvilai

Abstract:

Obstacle avoidance is the one key for the robot system in unknown environment. The robots should be able to know their position and safety region. This research starts on the path planning which are SLAM and AMCL in ROS system. In addition, the best parameters of the obstacle avoidance function are required. In situation on Hard Disk Drive Manufacturing, the distance between robots and obstacles are very serious due to the manufacturing constraint. The simulations are accomplished by the SLAM and AMCL with adaptive velocity and safety region calculation.

Keywords: obstacle avoidance, OA, Simultaneous Localization and Mapping, SLAM, Adaptive Monte Carlo Localization, AMCL, KLD sampling, KLD

Procedia PDF Downloads 170

Authors: Mabroka Omar Sherehe

Abstract:

Despite the great efficacy of isoniazid (INH) and rifampicine (RIF) combination in the treatment of tuberculosis, hepatotoxicity is the most common serious complication. The potential protective effect of simvastatin (sim) against combination-induced hepatotoxicity was investigated in the present study. The administration of INH-RIF combination (50mg/kg each for 14 days) resulted in a significant increased activities of serum alanine and aspartate aminotransferases, such effects were further supported by histopathological studies. INH-RIF combination produced a significant increase in liver lipid, decreased SOD and CAT, and a significant depletion of GSH level. Additionally, treatment with INH-RIF combination resulted in a significant increase in liver MPO activity. The lipid-lowering drug, Sim demonstrated in the current study an evident antioxidant action, such effect was mediated via decreasing the elevated MDA, MPO, and restoring liver CAT activity. Additionally, Sim restored liver NO level to near basal value Furthermore, one cannot rule out the lipid-lowering effect of Sim that would probably add to its beneficial hepatoprotective antioxidant activity, where Sim decreased the elevated cholesterol, TGs and LDL cholesterol level and increased the serum HDL cholesterol level.

Keywords: isoniazid, rifampicine, oxidative stress, nitric oxide

Procedia PDF Downloads 589

Authors: Amir Davood Elmi

Abstract:

From the earliest light microscope to the most innovative X-ray imaging techniques, all of them have refined and improved our knowledge about the organization and composition of living tissues. The old techniques are time consuming and ultimately destructive to the tissues under the examination. In recent few decades, thanks to the boost of technology, non-destructive visualization techniques, such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), selective plane illumination microscopy (SPIM), and optical projection tomography (OPT), have come to the forefront. Among these techniques, CT is excellent for mineralized tissues such as bone or dentine. In addition, CT it is faster than other aforementioned techniques and the sample remains intact. In this article, applications, advantages, and limitations of micro-CT is discussed, in addition to some information about micro-CT of soft tissue.

Keywords: Micro-CT, hard tissue, bone, attenuation coefficient, rapid prototyping

Procedia PDF Downloads 113

Authors: N. Kekelidze, B. Kvirkvelia, E. Khutsishvili, T. Qamushadze, D. Kekelidze, R. Kobaidze, Z. Chubinishvili, N. Qobulashvili, G. Kekelidze

Abstract:

On the basis of InAs, InP and their InP_xAs_1-x solid solutions, the technologies were developed and materials were created where the electron concentration and optical and thermoelectric properties do not change under the irradiation with Ф = 2∙10¹⁸ n/cm² fluences of fast neutrons high-energy electrons (50 MeV, Ф = 6·10¹⁷ e/cm²) and 3 MeV electrons with fluence Ф = 3∙10¹⁸ e/cm². The problem of obtaining such material has been solved, in which under hard irradiation the mobility of the electrons does not decrease, but increases. This material is characterized by high thermal stability up to T = 700 °C. The complex process of defects formation has been analyzed and shown that, despite of hard irradiation, the essential properties of investigated materials are mainly determined by point type defects.

Keywords: InAs, InP, solid solutions, irradiation

Procedia PDF Downloads 153

Authors: Kalsoom Shaikh, Ghulam Sarwar Gachal, Saima Memon

Abstract:

Our study aimed to assess diversity and habitats of amphibian fauna in Sindh province as amphibians are among most vulnerable animals and the risk of their extinction is increasing in many parts of world mainly due to habitat degradation. Present study consisted of field surveys and laboratory analytical work; field surveys were carried out to confirm amphibian diversity and collection of water samples from their habitats, whereas laboratory work was conducted for identification of species and analysis of water quality of habitats through physico-chemical parameters. For identification of amphibian species, morphology was thoroughly examined using taxonomic key, whereas water quality was assessed via physico-chemical parameters including pH, electric conductivity (EC), total dissolved solids (TDS), total hardness (T. Hard), total alkalinity (T. Alk), chloride (Cl), carbon dioxide (CO₂), sulfate (SO₄), phosphate (PO₄), nitrite (NO₂) and nitrate (NO₃) using material and methods of analytical grade. pH value was analyzed using pH meter, whereas levels of EC and TDS were recorded using conductivity meter and TDS meter, respectively. Other parameters with exception of non-metallic parameters (SO₄, PO₄, NO₂, and NO₃) were analyzed through distinct titration methods. Concentration of non-metallic parameters was evaluated using ultra-violet spectrophotometer. This study revealed existence of four amphibian species including Hoplobatrachus tigerinus, Euphlyctis cyanophlyctis, Allopa hazarensis belonging to Family Ranidae and Bufo stomaticus (Family Bufonidae) randomly distributed in district Ghotki, Jamshoro, Kashmor, Larkana, Matiari and Shikarpur in Sindh. Assessment of aquatic habitats in different areas found value of parameters as followed: Habitats in district Ghoki (pH: 7.8 ± 0.3, EC: 2165.3 ± 712.6, TDS: 1507.0 ± 413.1, T-Hard: 416.4 ± 67.5, T. Alk: 393.4 ± 78.4, Cl: 362.4 ± 70.1, CO₂: 21.1 ± 3.5, SO₄: 429.3 ± 100.1, PO₄: 487.5 ± 122.5, NO₂: 13.7 ± 1.0, NO₃: 14.7 ± 2.5), district Jamshoro habitats (pH: 8.1 ± 0.4, EC: 2403.8 ± 55.4, TDS: 1697.2 ± 77.0, T. Hard: 548.7 ± 43.2, T. Alk: 294.4 ± 29.0, Cl: 454.7 ± 50.8 CO₂: 16.9 ± 2.4, SO₄: 713.0 ± 49.3, PO₄: 826.2 ± 53.0, NO₂: 15.2 ± 3.4, NO₃: 21.6 ± 3.7), habitats in Kashmor district (pH: 8.0 ± 0.5, EC: 2450.3 ± 610.9, TDS: 1745.3 ± 440.9, T. Hard: 624.6 ± 305.8, T. Alk: 445.7 ± 120.5, Cl: 448.9 ± 128.8, CO₂: 18.9 ± 4.5, SO₄: 619.8 ± 205.8, PO₄: 474.1 ± 94.2, NO₂: 15.2 ± 3.1, NO₃ 14.3 ± 2.6), district Larkana habitats (pH: 8.4 ± 0.4, EC: 2555.8 ± 70.3, TDS: 1784.4 ± 36.9, T. Hard: 623.0 ± 42.5, T. Alk: 329.6 ± 36.7, Cl: 614.3 ± 89.5, CO₂: 17.6 ± 1.2, SO₄: 845.1 ± 67.6, PO₄: 895.0 ± 61.4, NO₂: 13.6 ± 3.8, NO₃: 23.1 ± 2.8), district Matiari habitats (pH: 8.0 ± 0.4 EC: 2492.3 ± 928.1, TDS: 430.0 ± 161.3, T. Hard: 396.7 ± 183.3, T. Alk: 388.1 ± 97.4, Cl: 551.6 ± 73.4, CO₂: 15.8 ± 2.9, SO₄: 576.5 ± 200.0, PO₄: 434.7 ± 100.6, NO₂: 15.8 ± 2.9, NO₃: 15.2 ± 3.0) and habitats in Shikarpur district (pH: 8.1 ± 0.6, EC: 2191.7 ± 765.1, TDS: 1764.9 ± 409.2, T. Hard: 431.9 ± 68.4,T. Alk: 350.3 ± 44.3, Cl: 381.5 ± 29.5, CO₂: 18.0 ± 4.0, SO₄: 518.8 ± 97.9, PO₄: 493.6 ± 64.6, NO₂: 14.0 ± 0.8, NO₃: 16.1 ± 2.8). Values of physico-chemical parameters were found higher than permissible level of Environmental Protectiona Agency (EPA). Monthly variation in concentration of physico-chemical parameters was also prominently recorded at all the study locals. This study discovered poor diversity of amphibian fauna and condition of their habitats was also observed as pitiable. This study established base line information that may be used in execution of an effective management plan and future monitoring of amphibian diversity and their habitats in Sindh.

Keywords: amphibians, diversity, habitats, Pakistan, Sindh

Procedia PDF Downloads 127

Authors: Pedro Luis Ferrer Penalver, Edmundo da Silva Braga

Abstract:

In this paper, the performance of a simple surge protection for a direct current circuit was simulated. The protection circuit was developed from modified electric macro models of a gas discharge tube and a transient voltage suppressor diode. Moreover, a combination wave generator circuit was used as source of energy surges. The simulations showed that the circuit presented ensures immunity corresponding with test level IV of the IEC 61000-4-5:2014 international standard. The developed circuit can be modified to meet the requirements of any other equipment to be protected. Similarly, the parameters of the combination wave generator can be changed to provide different surge amplitudes.

Keywords: combination wave generator, IEC 61000-4-5, Pspice simulation, surge protection

Procedia PDF Downloads 295

Authors: Ameni Mejri, Moufida Hajjaj, Salem Hasnaoui, Ridha Bouallegue

Abstract:

The technology advances have most lately made the millimeter wave (mmWave) communication possible. Due to the huge amount of spectrum that is available in MmWave frequency bands, this promising candidate is considered as a key technology for the deployment of 5G cellular networks. In order to enhance system capacity and achieve spectral efficiency, very large antenna arrays are employed at mmWave systems by exploiting array gain. However, it has been shown that conventional beamforming strategies are not suitable for mmWave hardware implementation. Therefore, new features are required for mmWave cellular applications. Unlike traditional multiple-input-multiple-output (MIMO) systems for which only digital precoders are essential to accomplish precoding, MIMO technology seems to be different at mmWave because of digital precoding limitations. Moreover, precoding implements a greater number of radio frequency (RF) chains supporting more signal mixers and analog-to-digital converters. As RF chain cost and power consumption is increasing, we need to resort to another alternative. Although the hybrid precoding architecture has been regarded as the best solution based on a combination between a baseband precoder and an RF precoder, we still do not get the optimal design of hybrid precoders. According to the mapping strategies from RF chains to the different antenna elements, there are two main categories of hybrid precoding architecture. Given as a hybrid precoding sub-array architecture, the partially-connected structure reduces hardware complexity by using a less number of phase shifters, whereas it sacrifices some beamforming gain. In this paper, we treat the hybrid precoder design in mmWave MIMO systems as a problem of matrix factorization. Thus, we adopt the alternating minimization principle in order to solve the design problem. Further, we present our proposed algorithm for the partially-connected structure, which is based on the iterative hard thresholding method. Through simulation results, we show that our hybrid precoding algorithm provides significant performance gains over existing algorithms. We also show that the proposed approach reduces significantly the computational complexity. Furthermore, valuable design insights are provided when we use the proposed algorithm to make simulation comparisons between the hybrid precoding partially-connected structure and the fully-connected structure.

Keywords: alternating minimization, hybrid precoding, iterative hard thresholding, low-complexity, millimeter wave communication, partially-connected structure

Procedia PDF Downloads 293

Authors: H. Weigelt-Marom

Abstract:

Over the years and up to the arousal of the COVID-19 pandemic, deaf or hard of hearing students studying in higher education institutions, participated lectures on campus using hearing aids and strategies adapted for frontal learning in a classroom. Usually, these aids were well known to them from their earlier study experience in school. However, the transition to online lessons, due to the latest pandemic, led deaf or hard of hearing students to study outside of their physical, well known learning environment. The change of learning environment and structure rose new challenges for these students. The present study examined the learning experience, limitations, challenges and benefits regarding learning online with lecture and classmates via the “Zoom” video conference program, among deaf or hard of hearing students in academia setting. In addition, emotional and social aspects related to learning in general versus the “Zoom” were examined. The study included 18 students diagnosed as deaf or hard of hearing, studying in various higher education institutions in Israel. All students had experienced lessons on the “Zoom”. Following allocation of the group study by the deaf and hard of hearing non-profit organization “Ma’agalei Shema”, and receiving the participants inform of consent, students were requested to answer a google form questioner and participate in an interview. The questioner included background information (e.g., age, year of studying, faculty etc.), level of computer literacy, and level of hearing and forms of communication (e.g., lip reading, sign language etc.). The interviews included a one on one, semi-structured, in-depth interview, conducted by the main researcher of the study (interview duration: up to 60 minutes). The interviews were held on “ZOOM” using specific adaptations for each interviewee: clear face screen of the interviewer for lip and face reading, and/ or professional sign language or live text transcript of the conversation. Additionally, interviewees used their audio devices if needed. Questions regarded: learning experience, difficulties and advantages studying using “Zoom”, learning in a classroom versus on “Zoom”, and questions concerning emotional and social aspects related to learning. Thematic analysis of the interviews revealed severe difficulties regarding the ability of deaf or hard of hearing students to comprehend during ”Zoom“ lessons without adoptive aids. For example, interviewees indicated difficulties understanding “Zoom” lessons due to their inability to use hearing devices commonly used by them in the classroom (e.g., FM systems). 80% indicated that they could not comprehend “Zoom” lessons since they could not see the lectures face, either because lectures did not agree to open their cameras or, either because they did not keep a straight forward clear face appearance while teaching. However, not all descriptions regarded learning via the “zoom” were negative. For example, 20% reported the recording of “Zoom” lessons as a main advantage. Enabling then to repeatedly watch the lessons at their own pace, mostly assisted by friends and family to translate the audio output into an accessible input. These finding and others regarding the learning experience of the group study on the “Zoom”, as well as their recommendation to enable deaf or hard of hearing students to study inclusively online, will be presented at the conference.

Keywords: deaf or hard of hearing, learning experience, Zoom, qualitative research

Procedia PDF Downloads 89

Authors: Maria Ana T. Quimbo

Abstract:

As the Southeast Asian Regional Center for Graduate Study and Research in Agriculture (SEARCA) approaches its 50th founding anniversary. It continues to pursue its mission of strengthening the capacities of Southeast Asian leaders and institutions under its reformulated mission of Inclusive and Sustainable Agricultural and Rural Development (ISARD). Guided by this mission, this study analyzed the desired and priority capacity development needs of institutions heads and key personnel toward addressing the constraints, problems, and issues related to agricultural and rural development toward achieving their institutional goals. Adopting an exploratory, descriptive research design, the study examined the competency needs at the institutional and personnel levels. A total of 35 institution heads from seven countries and 40 key personnel from eight countries served as research participants. The results showed a variety of competencies in the areas of leadership and management, agriculture, climate change, research, monitoring, and evaluation, planning, and extension or community service. While mismatch was found in a number of desired and priority competency areas as perceived by the respondents, there were also interesting concordant answers in both technical and non-technical areas. Interestingly, the competency needs both desired and prioritized were a combination of “hard” or technical skills and “soft” or interpersonal skills. Policy recommendations were forwarded on the need to continue building capacities in core competencies along ISARD; have a balance of 'hard' skills and 'soft' skills through the use of appropriate training strategies and explicit statement in training objectives, strengthen awareness on “soft” skills through its integration in workplace culture, build capacity on action research, continue partnerships encourage mentoring, prioritize competencies, and build capacity of desired and priority competency areas.

Keywords: capacity development, competency needs assessment, sustainability and development, ISARD

Procedia PDF Downloads 350

Authors: Jatinder Kumar

Abstract:

Ultrasonic machining is one of the most widely used non-traditional machining processes for machining of materials that are relatively brittle, hard and fragile such as advanced ceramics, refractories, crystals, quartz etc. There is a considerable lack of research on its application to the cost-effective machining of tough materials such as titanium. In this investigation, the application of USM process for machining of titanium (ASTM Grade-I) has been explored. Experiments have been conducted to assess the effect of different parameters of USM process on machining rate and tool wear rate as response characteristics. The process parameters that were included in this study are: abrasive grit size, tool material and power rating of the ultrasonic machine. It has been concluded that titanium is fairly machinable with USM process. Significant improvement in the machining rate can be realized by manipulating the process parameters and obtaining the optimum combination of these parameters.

Keywords: abrasive grit size, tool material, titanium, ultrasonic machining

Procedia PDF Downloads 334

Authors: V. Pourmostaghimi, M. Zadshakoyan

Abstract:

Efficiency and productivity of the finish hard turning can be enhanced impressively by utilizing accurate predictive models for cutting tool wear. However, the ability of genetic programming in presenting an accurate analytical model is a notable characteristic which makes it more applicable than other predictive modeling methods. In this paper, the genetic equation for modeling of tool flank wear is developed with the use of the experimentally measured flank wear values and genetic programming during finish turning of hardened AISI D2. Series of tests were conducted over a range of cutting parameters and the values of tool flank wear were measured. On the basis of obtained results, genetic model presenting connection between cutting parameters and tool flank wear were extracted. The accuracy of the genetically obtained model was assessed by using two statistical measures, which were root mean square error (RMSE) and coefficient of determination (R²). Evaluation results revealed that presented genetic model predicted flank wear over the study area accurately (R² = 0.9902 and RMSE = 0.0102). These results allow concluding that the proposed genetic equation corresponds well with experimental data and can be implemented in real industrial applications.

Keywords: cutting parameters, flank wear, genetic programming, hard turning

Procedia PDF Downloads 149

Authors: M. Bahgat, F. M. Awan, H. A. Hanafy

Abstract:

The conventional ceramic route was utilized to prepare a hard magnetic powder (M-type strontium ferrite, SrFe12O19). The stoichiometric mixture of iron oxide and strontium carbonate were calcined at 1000°C and then fired at various temperatures. The influence of various reaction parameters such as mixing ratio, calcination temperature, firing temperature and firing time on the magnetic behaviors of the synthesized magnetic powder were investigated.The magnetic properties including Coercivity (Hc), Magnetic saturation (Ms), and Magnetic remnance (Mr) were measured by vibrating sample magnetometer. Morphologically the produced magnetic powder has a dense hexagonal grain shape structure.

Keywords: hard magnetic materials, ceramic route, strontium ferrite, magnetic properties

Procedia PDF Downloads 660