Search results for: combined effect

Authors: Abdelaziz Rabhi, Mohamed Amrani, Abderrazek Ziane, Nabil Belkadi, Abdelraouf Hocini

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In this paper, a bedimensional simulation program of the electric characteristics of reverse biased lateral polysilicon PIN diode is presented. In this case we have numerically solved the system of partial differential equations formed by Poisson's equation and both continuity equations that take into account the effect of impact ionization. Therefore we will obtain the current-voltage characteristics (I-V) of the reverse-biased structure which may include the effect of breakdown.The geometrical model assumes that the polysilicon layer is composed by a succession of defined mean grain size crystallites, separated by lateral grain boundaries which are parallel to the metallurgic junction.

Keywords: breakdown, polycrystalline silicon, PIN, grain, impact ionization

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Authors: Lisa J. Piergallini

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This project uses panel regression analyses to investigate the relationships between geography, institutions, and economic development, as guided by the theories of the 18^th century French philosopher Montesquieu. Contemporary scholars of political economy perpetually misinterpret Montesquieu’s theories on climate, and in doing so they miss what could be the key to resolving the geography vs. institutions debate. There is a conspicuous gap in this literature, in that it does not consider whether geography and institutors might have an interactive, dynamic effect on economic development. This project seeks to bridge that gap. Data are used for all available countries over the years 1980-2013. Two interaction terms between geographic and institutional variables are employed within the empirical analyses, and these offer a unique contribution to the ongoing geography vs. institutions debate within the political economy literature. This study finds that there is indeed an interactive effect between geography and institutions, and that this interaction has a statistically significant effect on economic development. Democracy (as measured by Polity score) and rule of law and property rights (as measured by the Fraser index) have positive effects on economic development (as measured by GDP per capita), yet the magnitude of these effects are stronger in contexts where a low percent of the national population lives in the geographical tropics. This has implications for promoting economic development, and it highlights the importance of understanding geographical context.

Keywords: Montesquieu, institutions, geography, economic development, political philosophy, political economy

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Authors: Segun Thompson Bolarinwa, Munacinga Simatele, Adedamola Victoria Adegbuyi

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Using World Bank’s nascent measure of sustainability, this paper examines the relationship between informality and sustainability in selected 7 African and 7 European developing economies. Specifically, the work examines the roles of informality on sustainability, interactive effect of globalisation in the nexus and the threshold of informality on sustainability suing spatial econometric and dynamic panel threshold panel models. Overall, the results indicate mixed effects of positive and negative pf informality on sustainability in Africa and Europe respectively. Recommendations are presented.

Keywords: spatial and dynamic, informality, Africa, Europe, globalisation, sustainability

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Authors: Jaehong Kim, Sunhee Park, HongSeop Shin, Kyongho Lim, Suhyun Kwon, Don-Gyou Lee, Pureum Kim, Moojong Lim, JongSang Baek

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Transparent displays with OLEDs are the most commonly produced forms of see-through displays on the market or in development. In order to block the visual interruption caused by the light coming from the background, the special panel is combined with transparent displays with OLEDs. There is, however, few studies optical performance of operational shutter panel for transparent displays until now. This paper, therefore, describes the optical performance of operational shutter panels. The novel evaluation method was developed by measuring the amount of light which can form a transmitted background image. The new proposed method could tell how recognize transmitted background images cannot be seen, and is consistent with viewer’s perception.

Keywords: transparent display, operational shutter panel, optical performance, OLEDs

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Authors: Chonlakorn Wiboonsiriruk, Ekachai Phaisangittisagul, Chadchai Srisurangkul, Itsuo Kumazawa

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Public transportation is a crucial aspect of passenger transportation, with buses playing a vital role in the transportation service. Passenger counting is an essential tool for organizing and managing transportation services. However, manual counting is a tedious and time-consuming task, which is why computer vision algorithms are being utilized to make the process more efficient. In this study, different object detection algorithms combined with passenger tracking are investigated to compare passenger counting performance. The system employs the EfficientDet algorithm, which has demonstrated superior performance in terms of speed and accuracy. Our results show that the proposed system can accurately count passengers in varying conditions with an accuracy of 94%.

Keywords: computer vision, object detection, passenger counting, public transportation

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Authors: Patel Himeshkumar Ashokbhai, Suchit Sharma, Arvind Kumar Garg

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The purpose of this paper is to study the effect of change in feed rate on grinding circuit and cyclone efficiency in case of lead-zinc ore. The following experiments and analysis were conducted on beneficiation circuit of Sindesar Khurd (SK) mines under Hindustan Zinc Ltd. subsidiary of Vedanta Group of Companies, a leading producer of lead-Zinc, silver and cadmium (as by products) in India. Feed rate is an important variable in beneficiation circuit operation. Optimizing feed rate is indispensable for any grinding circuit and directly effects cyclone efficiency. The size analysis of ore in grinding circuit along with cyclone efficiency on varying feed rates establishes their interdependence. Feed rate determines retention time ore gets within grinding circuit. Retention time in turn determines degree of liberation of mineral. Inadequate liberation causes decreased circuit efficiency. In this paper we have studied the effect of varying feed rate on (1) D80 particle size of different sections of different streams of grinding circuit (2) Re-circulating load (3) Cyclone efficiency. As a conclusion, this study gives some clues to operate grinding circuits and hydro-cyclones in more efficient way regarding beneficiation of Lead-zinc ore.

Keywords: cyclone efficiency, feed rate, grinding circuit, re-circulating load

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Authors: Adel Belal, Sameh Aboelsoud, Mohy Elmashad, Mohammed Abdelmonem

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The two main criteria that control the design and performance of footings are bearing capacity and settlement of soil. In soft soils, the construction of buildings, storage tanks, warehouse, etc. on weak soils usually involves excessive settlement problems. To solve bearing capacity or reduce settlement problems, soil improvement may be considered by using different techniques, including encased cement dust–lime columns. The proposed research studies the effect of adding floating encased cement dust and lime mix columns to soft clay on the clay-bearing capacity. Four experimental tests were carried out. Columns diameters of 3.0 cm, 4.0 cm, and 5.0 cm and columns length of 60% of the clay layer thickness were used. Numerical model was constructed and verified using commercial finite element package (PLAXIS 2D, V8.5). The verified model was used to study the effect of distributing columns around the footing at different distances. The study showed that the floating cement dust lime columns enhanced the clay-bearing capacity with 262%. The numerical model showed that the columns around the footing have a limit effect on the clay improvement.

Keywords: bearing capacity, cement dust – lime columns, ground improvement, soft clay

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Authors: Ramesh K. Adsul, V. R. Shinde, S. S. Jadhav

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The main aim of the present study was to explore the effect of various levels of parental acceptance – avoidance attitude on various areas of adjustment of urban and rural junior college students. It was hypothesized that 1. There exists no significant effect of various levels of parental acceptance attitude on adjustment of urban and rural junior college students. 2. There exists no significant effect of various levels of parental avoidance attitude on adjustment of urban and rural junior college students. 3. There would be no significant difference between urban and rural Junior College students on various areas of (home, health, social, and emotional) adjustment. The 847 students (427 boys and 420 girls) studying in 11th class of various Junior colleges in Sangli ,Satara and Kolhapur districts of Maharashtra State, India were selected by random sampling method. Study was conducted by using two psychological tests namely 1. Family Relationship Inventory. 2.Bell’s Adjustment Inventory. One way ANOVA was employed to find out the effect of parental acceptance – avoidance attitude and adjustment in various areas of urban and rural junior college students. ‘t’ test was used to find out the difference between urban and rural students on various areas of adjustment. The results of the study indicate that (1) It is observed that three groups of parental acceptance attitude (PA) are significantly varied on home and social adjustment. It means that PA affects home and social adjustment of adolescents. High PA creates excellent adjustment and low PA creates poor adjustment in adolescents. (2) Study revealed that PV significantly affects adjustment of adolescents. High PV significantly creates poor adjustment in adolescents than average and low PV. (3) There is significant difference between urban and rural adolescents on adjustment. Urban adolescents have better adjustment than rural adolescents.

Keywords: parental acceptance, avoidance attitude, adjustment, urban-rural student

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Authors: Mark Anthony Casimiro, Ivan Culaba, Cornelia Soto

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Misconceptions are the wrong concepts understood by the students which may come up based on what they experience and observe around their environment. This seemed to hinder students’ learning. In this study, six different misconceptions were determined by the researcher from the previous researches. Teachers play a vital role in the classroom. The use of appropriate strategies can contribute a lot in the success of teaching and learning Physics. The current study aimed to compare two strategies- Interactive Lecture Demonstration (ILD) and Inquiry-Based Instruction (IBI) in addressing students’ misconceptions in electric circuits. These two strategies are both interactive learning activities and student-centered. In ILD, the teacher demonstrates the activity and the students have their predictions while in IBI, students perform the experiments. The study used the mixed method in which quantitative and qualitative researches were combined. The main data of this study were the test scores of the students from the pretest and posttest. Likewise, an interview with the teacher, observer and students was done before, during and after the execution of the activities. Determining and Interpreting Resistive Electric Circuits Test version 2 (DIRECT v.2) was the instrument used in the study. Two sections of Grade 9 students from Kalumpang National High School were the respondents of the study. The two strategies were executed to each section; one class was assigned as the ILD group and the other class was the IBI group. The Physics teacher of the said school was the one who taught and executed the activities. The researcher taught the teacher the steps in doing the two strategies. The Department of Education level of proficiency in the Philippines was adopted in scoring and interpretation. The students’ level of proficiency was used in assessing students’ knowledge on electric circuits. The pretest result of the two groups had a p-value of 0.493 which was greater than the level of significance 0.05 (p >0.05) and it implied that the students’ level of understanding in the topic was the same before the execution of the strategies. The posttest results showed that the p-value (0.228) obtained was greater than the level of significance which is 0.05 (p> 0.05). This implied that the students from the ILD and IBI groups had the same level of understanding after the execution of the two strategies. This could be inferred that either of the two strategies- Interactive Lecture Demonstration and Inquiry-Based Instruction could be used in addressing students’ misconception in electric circuit as both had similar effect on the students’ level of understanding in the topic. The result of this study may greatly help teachers, administration, school heads think of appropriate strategies that can address misconceptions depending on the availability of their materials of their school.

Keywords: inquiry- based instruction, interactive lecture demonstration, misconceptions, mixed method

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Authors: Ezeoke Callistus Obiora, Ezeoke Nneka Angela

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The study investigated the effect of deficit financing on macroeconomic variables in Nigeria. The specific objectives included to find out the relationship between deficit financing and GDP, interest rate, inflation rate, money supply, exchange rate and private investment respectively on a time series covering a period of 44 years (1970 – 2013). The Ordinary Least Square multiple regression produced statistics for the coefficient of determination (R2), F-test, t-test used for the interpretation of the study. The findings revealed that Deficit financing has significant positive effect on GDP and exchange rate. Again, deficit financing has a positive and insignificant relationship inflation, money supply and investment. Only interest rate recorded negative yet insignificant relationship with deficit financing. The implications of the findings are that deficit financing can be a veritable tool for boosting economic development in Nigeria, but the influential positively rising exchange rate implies that deficit financing devalues the Naira exchange rate to other currencies indicating that deficit financing can affect Nigerians competitive advantage at the world market. Thus, the study concludes that deficit financing has not encouraged economic growth in Nigeria.

Keywords: deficit financing, money supply, exchange rate, inflation, GDP, investment, Nigeria

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Authors: Junze Li, M. Li

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Laser diodes fabricated from the III-nitride material system are emerging solutions for the next generation telecommunication systems and optical clocks based on Ca at 397nm, Rb at 420.2nm and Yb at 398.9nm combined 556 nm. Most of the applications require single longitudinal optical mode lasers, with very narrow linewidth and compact size, such as communication systems and laser cooling. In this case, the GaN based distributed feedback (DFB) laser diode is one of the most effective candidates with gratings are known to operate with narrow spectra as well as high power and efficiency. Given the wavelength range, the period of the first-order diffraction grating is under 100 nm, and the realization of such gratings is technically difficult due to the narrow line width and the high quality nitride overgrowth based on the Bragg grating. Some groups have reported GaN DFB lasers with high order distributed feedback surface gratings, which avoids the overgrowth. However, generally the strength of coupling is lower than that with Bragg grating embedded into the waveguide within the GaN laser structure by two-step-epitaxy. Therefore, the overgrowth on the grating technology need to be studied and optimized. Here we propose to fabricate the fine step shape structure of first-order grating by the nanoimprint combined inductively coupled plasma (ICP) dry etching, then carry out overgrowth high quality AlGaN film by metalorganic chemical vapor deposition (MOCVD). Then a series of gratings with different period, depths and duty ratios are designed and fabricated to study the influence of grating structure to the nano-heteroepitaxy. Moreover, we observe the nucleation and growth process by step-by-step growth to study the growth mode for nitride overgrowth on grating, under the condition that the grating period is larger than the mental migration length on the surface. The AFM images demonstrate that a smooth surface of AlGaN film is achieved with an average roughness of 0.20 nm over 3 × 3 μm2. The full width at half maximums (FWHMs) of the (002) reflections in the XRD rocking curves are 278 arcsec for the AlGaN film, and the component of the Al within the film is 8% according to the XRD mapping measurement, which is in accordance with design values. By observing the samples with growth time changing from 200s, 400s to 600s, the growth model is summarized as the follow steps: initially, the nucleation is evenly distributed on the grating structure, as the migration length of Al atoms is low; then, AlGaN growth alone with the grating top surface; finally, the AlGaN film formed by lateral growth. This work contributed to carrying out GaN DFB laser by fabricating grating and overgrowth on the nano-grating patterned substrate by wafer scale, moreover, growth dynamics had been analyzed as well.

Keywords: DFB laser, MOCVD, nanoepitaxy, III-niitride

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Authors: Ajay Kadam, Ramesh Kagalkar

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The proposed research objective is to add to a framework for programmed recognition of sound. In this framework the real errand is to distinguish any information sound stream investigate it & anticipate the likelihood of diverse sounds show up in it. To create and industrially conveyed an adaptable sound web crawler a flexible sound search engine. The calculation is clamor and contortion safe, computationally productive, and hugely adaptable, equipped for rapidly recognizing a short portion of sound stream caught through a phone microphone in the presence of frontal area voices and other predominant commotion, and through voice codec pressure, out of a database of over accessible tracks. The algorithm utilizes a combinatorial hashed time-recurrence group of stars examination of the sound, yielding ordinary properties, for example, transparency, in which numerous tracks combined may each be distinguished.

Keywords: fingerprinting, pure tone, white noise, hash function

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Authors: Syeda Hira, Muhammad Gulfraz

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Background: Liver diseases cause serious health issues. Plants contain active compounds that significantly help in the treatment of various diseases. Ficus carica is traditionally used for the treatment of liver diseases. The purpose of the present study was the isolation and identification of active components from F.carica leaves which are responsible for hepatoprotective activity. Methods: The study was designed to identify the most active hepatoprotective sub-fraction from ethyl acetate fraction of Ficus carica by in vitro study and evaluation of its in vivo hepatoprotective effect in animal models. Ethyl acetate fraction was subjected to column, and a total of eight sub-fractions were obtained. In vitro, the hepatoprotective effect of all sub-fractions was determined on HepG2 cell lines. Toxicity was induced by CCl₄ (Carbon tetrachloride), and silymarin was used as a positive control. On the basis of the results, the most active sub-fraction was subjected to LC-MS and FT-IR analysis for the identification of bioactive compounds. In vivo, the hepatoprotective effect was determined in mice. Toxicity was induced by CCl₄; at the end of the experiment, biochemical parameters such as ALT, AST, ALP, bilirubin, and total protein were estimated in serum. Histopathology of liver tissues was also done. Results: Sub-fraction FVI exhibited significant (P<0.05) hepatoprotective activity as compared to other sub-fractions, which was almost similar to the standard drug silymarin. Six known bioactive compounds were identified from this sub-fraction after LC-MS analysis. In vivo, the hepatoprotective activity of sub-fraction FVI was evaluated in CCl₄-induced toxicated mice. Administration of CCl₄ significantly increased level of ALT (Alanine transaminase), AST (Aspartate aminotransferase), ALP (Alkaline phosphatase), and bilirubin and decreased the total protein. Treatment with sub-fraction FVI significantly (p<0.05) reversed the level of these biomarkers toward normal at both doses of 25 mg/kg and 50 mg/kg. Conclusion: Our findings confirmed the hepatoprotective effect of ethyl acetate fraction of F.carica. It could be a good candidate for the development of a natural hepatoprotective drug; pre-clinical investigation on ethyl acetate fraction is recommended.

Keywords: Ficus carica, hepatoprotective, CCl₄, bioactive compounds, liver markers

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Authors: T. S. Desak Ketut, A.n. Isna, A.a. Ayu, D. P. Ririn, Suharjono Hadiatullah

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The requirement of paper from year to year rise rapidly. The raising of cellulose requirement in paper production caused increasing of wood requirement with the effect that limited forest areal because of deforestation. Alternative cellulose that can be used for making paper is microbial cellulose. The objective of this research are to know the effectivity fermentation media Spirogyra sp. by Gluconacetobacter xylinum for cellulose production as material for the making of paper and to know effect composition bacterial cellulose composite product of Gluconacetobacter xylinum in Spirogyra sp. The method, was used, is as follow, 1) the effect assay from variation composition of fermentation media to bacterial cellulose production by Gluconacetobacter xylinum. 2) The effect assay of composition bacterial cellulose fermentation producted by Gluconacetobacter xylinum in extracted Spirogyra media to paper quality. The result of this research is variation fermentation media Spirogyra sp. affect to production of cellulose by Gluconacetobacter xylinum. Thus, result showed by the highest value and significantly different in thickness parameter, dry weight and wet weight of nata in sucrose concentration 7,5 % and urea 0,75 %. Composition composite of bacterial cellulose from fermentation product by Gluconacetobacter xylinum in media Spirogyra sp. affect to paper quality from wet nata and dry nata. Parameters thickness, weight, water absorpsion, density and gramatur showed highest result in sucrose concentration 7,5 % and urea concentration 0,75 %, except paper density from dry nata had highest result in sucrose and urea concentration 0%.

Keywords: cellulose, fermentation media, , Gluconacetobacter xylinum, paper, Spirogyra sp.

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Authors: Do-Jin Jang, Sung-Ah Kim

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A kinetic façade responds to user requirements and environmental conditions.  In designing a kinetic façade, kinetic patterns play a key role in determining its performance. This paper proposes a biomimetic method for the multi-objective optimization for kinetic façade design. The autonomous decentralized control system is combined with flocking algorithm. The flocking agents are autonomously reacting to sensor values and bring about kinetic patterns changing over time. A series of experiments were conducted to verify the potential and limitations of the flocking based decentralized control. As a result, it could show the highest performance balancing multiple objectives such as solar radiation and openness among the comparison group.

Keywords: biomimicry, flocking algorithm, autonomous decentralized control, multi-objective optimization

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Authors: Mina Boroujerdi, Javad Tavakoli

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Hydrogels are extensively studied as matrices for the controlled release of drugs. To evaluate the mobility of embedded molecules, these drug delivery systems are usually characterized by release studies. In this contribution, an electronic device for swelling pressure measurement during drug release from hydrogel network was developed. Also, poly acrylic acid micro particles were prepared for prolonged and sustained controlled acetaminophen release. Effect of swelling pressure on drug release from micro particles studied under different environment pH in order to predict release profile in gastro-intestine medium. Swelling ratio and swelling pressure were measured in different pH.

Keywords: swelling pressure, drug delivery, hydrogel, polyelectrolyte

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Authors: Abdulaziz Almustafa

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Considering the critical role permanence has on predictions related to the contextual interference effect on laboratory and field research, this study sought to determine whether the paradigm of the effect depends on the complexity of the skill during the acquisition and transfer phases. The purpose of the present study was to investigate the effects of contextual interference CI by extending previous laboratory and field research with adult athletes through the acquisition and transfer phases. Male (n=60) athletes age 18-22 years-old, were chosen randomly from Eastern Province Clubs. They were assigned to complete blocked, random, or serial practices. Analysis of variance with repeated measures MANOVA indicated that, the results did not support the notion of CI. There were no significant differences in acquisition phase between blocked, serial and random practice groups. During the transfer phase, there were no major differences between the practice groups. Apparently, due to the task complexity, participants were probably confused and not able to use the advantages of contextual interference. This is another contradictory result to contextual interference effects in acquisition and transfer phases in sport settings. One major factor that can influence the effect of contextual interference is task characteristics as the nature of level of difficulty in sport-related skill.

Keywords: contextual interference, acquisition, transfer, task difficulty

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Authors: Abdi Ismail, Zain Amarta, Riza Rifaldy Argaputra

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The Helical Turbine has the highest efficiency in comparison with the other hydrokinetic turbines. However, the potential of the Helical Turbine efficiency can be further improved so that the kinetic energy of a water current can be converted into mechanical energy as much as possible. This paper explains the effects by adding a Movable Airfoil Arm (MAA) and ducting on a Helical Turbine. The first research conducted an analysis of the efficiency comparison between a Plate Arm Helical Turbine (PAHT) versus a Movable Arm Helical Turbine Airfoil (MAAHT) at various water current velocities. The first step is manufacturing a PAHT and MAAHT. The PAHT and MAAHT has these specifications (as a fixed variable): 80 cm in diameter, a height of 88 cm, 3 blades, NACA 0018 blade profile, a 10 cm blade chord and a 60o inclination angle. The MAAHT uses a NACA 0012 airfoil arm that can move downward 20o, the PAHT uses a 5 mm plate arm. At the current velocity of 0.8, 0.85 and 0.9 m/s, the PAHT respectively generates a mechanical power of 92, 117 and 91 watts (a consecutive efficiency of 16%, 17% and 11%). At the same current velocity variation, the MAAHT respectively generates 74, 60 and 43 watts (a consecutive efficiency of 13%, 9% and 5%). Therefore, PAHT has a better performance than the MAAHT. Using analysis from CFD (Computational Fluid Dynamics), the drag force of MAA is greater than the one generated by the plate arm. By using CFD analysis, the drag force that occurs on the MAA is more dominant than the lift force, therefore the MAA can be called a drag device, whereas the lift force that occurs on the helical blade is more dominant than the drag force, therefore it can be called a lift device. Thus, the lift device cannot be combined with the drag device, because the drag device will become a hindrance to the lift device rotation. The second research conducted an analysis of the efficiency comparison between a Ducted Helical Turbine (DHT) versus a Helical Turbine (HT) through experimental studies. The first step is manufacturing the DHT and HT. The Helical turbine specifications (as a fixed variable) are: 40 cm in diameter, a height of 88 cm, 3 blades, NACA 0018 blade profile, 10 cm blade chord and a 60o inclination angle. At the current speed of 0.7, 0.8, 0.9 and 1.1 m/s, the HT respectively generates a mechanical power of 72, 85, 93 and 98 watts (a consecutive efficiency of 38%, 30%, 23% and 13%). At the same current speed variation, the DHT generates a mechanical power of 82, 98, 110 and 134 watts (a consecutive efficiency of 43%, 34%, 27% and 18%), respectively. The usage of ducting causes the water current speed around the turbine to increase.

Keywords: hydrokinetic turbine, helical turbine, movable airfoil arm, ducting

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Authors: Abel Olayinka Ogbungbemi, I. A. Omunagbe, O. R. King, O. H. Akingbade

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This study examined the influence of environmental factors on the academic performance of students in Lagos State Polytechnic. One hundred and thirty-eight students (138) questionnaire was randomly administered among 2,600 students in the 6 departments in the school of environmental studies, Lagos state Polytechnic. The result of the study established that the school environment affects learning. Hence, improper maintenance of fixtures led to lower than average student’s performance. Based on this, the school should endeavour to sustain the school facilities and dull colour points should not be used for painting, interactions between teachers and students should be encouraged, and teachers should relate to all the students irrespective of their age, level of study, department of study and gender.

Keywords: environment, learning, responsiveness, school effect

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Authors: S. Wagner, C. Boley, Y. Forouzandeh

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When digging excavations, groundwater bearing layers are often encountered. In order to allow anhydrous excavation, soil groutings are carried out, which form a water-impermeable layer. As it is injected into groundwater areas, the effects of the materials used on the environment must be known. Developing an eco-friendly, economical and low viscous acrylic gel which has a sealing effect on groundwater is therefore a significant task. At this point the study begins. Basic investigations with the rheometer and a reverse column experiment have been performed with different mixing ratios of an acrylic gel. A dynamic rheology study was conducted to determine the time at which the gel still can be processed and the maximum gel strength is reached. To examine the effect of acrylic gel grouting on determine the parameters pH value, turbidity, electric conductivity, and total organic carbon on groundwater, an acrylic gel was injected in saturated sand filled the column. The structure was rinsed with a constant flow and the eluate was subsequently examined. The results show small changes in pH values and turbidity but there is a dependency between electric conductivity and total organic carbon. The curves of the two parameters react at the same time, which means that the electrical conductivity in the eluate can be measured constantly until the maximum is reached and only then must total organic carbon (TOC) samples be taken.

Keywords: acrylic gel grouting, dynamic rheology study, electric conductivity, total organic carbon

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Authors: Zhenyu Lei, Chengshun Li

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To prevent the occurrence of rail corrugation and mitigate the influence of existing corrugation, this paper first conducts actual measurements of rail corrugation before and after the installation of the frequency-modulated rail dampers, determines the characteristic frequencies of corrugation and makes comparisons of the time-domain and frequency-domain of the vertical and lateral vibration accelerations of the rails. It indicates that the rail dampers significantly reduce the rail vibration acceleration levels at the characteristic frequencies, and the vibrations are significantly reduced after the installation of the dampers. Additionally, a simulation study is carried out on the wheel-rail system with and without the frequency-modulated rail dampers. The theory that resonance of the wheel-rail system leads to corrugation shows that rail vibration is inseparably associated with the generation of corrugation, and the potential causes of corrugation in each frequency band are explored through the natural frequencies of the system. Finally, the rail vibration attenuation rate index is calculated, describing the absorption effect of the frequency-modulated rail dampers on rail vibration. It indicates that the dampers absorb part of the lateral vibration energy of the rails and have the effect of altering the rail vibration characteristics in the frequency domain. It is considered that they have a positive influence on the suppression of rail corrugation.

Keywords: rail corrugation, frequency-modulated rail damper, finite element analysis, wheel-rail system resonance, rail vibration attenuation rate

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Authors: Wei Li, Tuo Yang

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In order to satisfy the real-time and accurate requirements of cigarette smoke detection in complex scenes, a cigarette smoke detection technology based on the combination of deep learning and color features was proposed. Firstly, based on the color features of cigarette smoke, the suspicious cigarette smoke area in the image is extracted. Secondly, combined with the efficiency of cigarette smoke detection and the problem of network overfitting, a network model for cigarette smoke detection was designed according to YOLOV3 algorithm to reduce the false detection rate. The experimental results show that the method is feasible and effective, and the accuracy of cigarette smoke detection is up to 99.13%, which satisfies the requirements of real-time cigarette smoke detection in complex scenes.

Keywords: deep learning, computer vision, cigarette smoke detection, YOLOV3, color feature extraction

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Authors: Chayonnat Thanamun, Kreangkrai Maneeintr

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For petroleum industry, polymer flooding is the one of the main methods in enhanced oil recovery (EOR) that is used water-soluble polymer such as partially hydrolyzed polyacrylamide (HPAM) to increase oil production. It is added to the flooding water to improve the mobility ratio in the flooding process. During the polymer flooding process, water is produced as a by-product along with oil and gas production. This produced water is a mixture of inorganic and organic compound. Moreover, produced water is more difficult to treat than that from water flooding. In this work, the effect of HPAM residue on the wastewater treatment from polymer flooding is studied. Polyaluminium chloride (PAC) is selected to use as a flocculant. Therefore, the objective of this study is to evaluate the effect of polymer residues in produced water on the wastewater treatment by using PAC. The operating parameters of this study are flocculant dosage ranging from 300,400 and 500 mg/L temperature from 30-50 Celsius degree and HPAM concentrations from 500, 1000 and 2000 mg/L. Furthermore, the turbidity, as well as total suspended solids (TSS), are also studied. The results indicated that with an increase in HPAM concentration, the TSS and turbidity increase gradually with the increasing of coagulant dosage under the same temperature. Also, the coagulation-flocculation performance is improved with the increasing temperature. This can be applied to use in the wastewater treatment from oil production before this water can be injected back to the reservoir.

Keywords: wastewater treatment, petroleum production, polyaluminium chloride, polyacrylamide

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Authors: Z. Mowafy Emam Mowafy, Ahmed R. Sayed, M. El Sayed Mohmmed Hassan

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Purpose: to evaluate the effect of low intensity laser on severe tinnitus in idiopathic sudden hearing loss patients. Methods of evaluation (Visual analogue scale and tinnitus handicap inventory scale):- Thirty patients who had unilateral tinnitus with sensorineural hearing loss were participated in the study. Subjects aged from 40 to 50 were randomly divided into two equal groups: group (A): composed of 15 patients who received the routine medical care (Systemic steroids) in addition to the low-intensity laser therapy (LILT) while group (B): composed of 15 patients who received only the routine medical care. Continuous 632.8nm He-Ne laser was used with 5mW power for 15 min\day, 3 days per week for 3 months. Results and conclusion: Results showed that application of the LILT had a valuable effect on severe tinnitus in idiopathic sudden hearing loss patients as evidenced by the highly decreased visual analogue scale and tinnitus handicap inventory scale.

Keywords: idiopathic sudden hearing loss, low intensity laser, tinnitus, tinnitus handicap inventory scale and visual analogue scale

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Authors: H. Babou, S. Ridjla, B. Amerate, R. Ferhoum, M. Aberkane

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This work is devoted to the experimental study of thermal ageing effect on the mechanical and micro structural behavior of polycarbonate (PC). A simple compression tests, micro hardness and an IRTF analysis were completed in order to characterize the response of material on specimens after ageing at a temperature of order 100 C° and for serval maintain duration 72, 144 and 216 hours. These investigations showed a decrease of the intrinsic properties of polycarbonate (Young modulus, yield stress, etc.); the superposition of spectra IRTF shows that the intensity of chemical connections C=C, C-O, CH3 and C-H are influenced by the duration of thermal ageing; in addition, an increase of 30 % of micro hardness was detected after 216 hour of ageing.

Keywords: amorphous polymer, polycarbonate, mechanical behavior, compression test, thermal ageing

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Authors: Emily Hamilton, Adiel Kahana, Ron Hauser, Shimi Barda

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BACKGROUND: In the male fertility and sperm bank unit of Tel Aviv Sourasky medical center, women are treated with intrauterine insemination (IUI) using washed sperm from their partner or thawed sperm from a selected donor. In most cases, the women perform the IUI treatment in Sourasky, but sometimes they ask to undergo the insemination procedure in another clinic with their own fertility doctor. In these cases, the sperm sample is prepared at the Sourasky lab and the patient is inseminated after arriving to her doctor. Our laboratory has previously found that time negatively affects several parameters of thawed sperm, and we estimate that it has more severe and significant effect than on washed sperm. AIM: To examine the effect of time on the quality of washed sperm versus thawed sperm. METHODS: Sperm samples were collected from men referred for semen analysis. Each ejaculate was allowed to liquefy for at least 20 min at 37°C and analyzed for sperm motility and vitality percentage and DNA fragmentation index (Time 0). Subsequently, 1ml of the sample was divided into two parts, 1st part was washed only and the 2nd part was washed, frozen and thawed. Time 1 analysis occurred immediately after sperm washing or thawing. Time 2 analysis occurred 75 minutes after time 1. Statistical analysis was performed using Student t-test. P values<0.05 were considered significant. RESULTS: Preliminary data showed that time had a greater impact on the average percentages of sperm motility and vitality in thawed compared to washed sperm samples (26%±10% vs. 21%±10% and 21%±9% vs. 9%±10%, respectively). An additional trend towards increased average DNA fragmentation percentage in thawed samples compared to washed samples was observed (46%±18% vs. 25%±24%). CONCLUSION: Time negatively effects sperm quality. The effect is greater in thawed samples compared to fresh samples.

Keywords: ART, male fertility, sperm cryopreservation, sperm quality

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Authors: Tahar Ghnaya, Majda Mnasri, Hanen Zaier, Rim Ghabriche, Chedly Abdelly

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It is known that the symbiotic association between plant and microorganisms are beneficial for plant growth and resistance to metal stress. Hence, it was demonstrated that Arbuscular mycorrhizal fungi have a positive effect on host plants growing in metal polluted soils. Legume plants are those which normally associate to rhizobacteria in order to fix atmospheric nitrogen. The aim of this work was to evaluate the effect this type of symbiosis on the tolerance and the accumulation of Cd. We chose Medicago sativa, as a modal for host legume plants and Rhizobium mililoti 2011 as rhizobial strain. Inoculated and non-inoculated plants of M. sativa were submitted during three month to 0, 50, and 100 mgCd/kg dry soil. Results showed that the presence of Cd in the medium induced, in both inoculated and non-inoculated plants, a chlorosis and necrosis. However, these symptoms were more pronounced in non-inoculated plants. The beneficial effect of inoculation of M. sativa with R. meliloti, on plant growth was confirmed by the measurement of biomass production which showed that the symbiotic association between host plant and rhizobacteria alleviates significantly Cd effect on biomass production, so inoculated plants produced more dry weight as compared to non-inoculated ones in the presence of all Cd tretments. On the other hand, under symbiosis conditions, Cd was more accumulated in different plant organs. Hence, in these plants, shoot Cd concentration reached 425 and it was 280 µg/gDW in non-inoculated ones in the presence of 100 ppm Cd. This result suggests that symbiosis enhances the absorption and translocation of Cd in this plant. In nodules and roots, we detected the highest Cd concentrations, demonstrating that these organs are able to concentrate Cd in their tissues. These data confirm that M. sataiva, cultivated in symbiosis with Rhizobium mililoti could be used in phytoextraction of Cd from contaminated soils.

Keywords: Cd, phytoremediation, Medicago sativa, Arbuscular mycorrhizal

Procedia PDF Downloads 277

Authors: Parvin Goli, Amirhosein Kefayat, Rezvan Goli

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Background: It is well established that parents can influence their offspring's neurodevelopment. It is shown that paternal environment and lifestyle is beneficial for the progeny's fitness and might affect their metabolic mechanisms; however, the effects of paternal exercise on the brain in the offspring have not been explored in detail. Objective: This study aims to review the impact of paternal physical exercise on memory and learning, neuroplasticity, as well as DNA methylation levels in the off-spring's hippocampus. Study design: In this systematic review and meta-analysis, an electronic literature search was conducted in databases including PubMed, Scopus, and Web of Science. Eligible studies were those with an experimental design, including an exercise intervention arm, with the assessment of any type of memory function, learning ability, or any type of brain plasticity as the outcome measures. Standardized mean difference (SMD) and 95% confidence intervals (CI) were computed as effect size. Results: The systematic review revealed the important role of environmental enrichment in the behavioral development of the next generation. Also, offspring of exercised fathers displayed higher levels of memory ability and lower level of brain-derived neurotrophic factor. A significant effect of paternal exercise on the hippocampal volume was also reported in the few available studies. Conclusion: These results suggest an intergenerational effect of paternal physical activity on cognitive benefit, which may be associated with hippocampal epigenetic programming in offspring. However, the biological mechanisms of this modulation remain to be determined.

Keywords: hippocampal plasticity, learning ability, memory, parental exercise

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Authors: HoYoung Son, Ki Young Kim, Woo Young Jung

Abstract:

This study investigated the change of weir structure performances when durability of concrete, which is the main material of weir structure, decreased due to their aging by mean of seismic fragility analysis. In the analysis, it was assumed that the elastic modulus of concrete was reduced by 10% in order to account for their aged deterioration. Additionally, the analysis of seismic fragility was based on Monte Carlo Simulation method combined with a 2D nonlinear finite element in ABAQUS platform with the consideration of deterioration of concrete. Finally, the comparison of seismic fragility of model pre- and post-deterioration was made to study the performance of weir. Results show that the probability of failure in moderate damage for deteriorated model was found to be larger than pre-deterioration model when peak ground acceleration (PGA) passed 0.4 g.

Keywords: weir, FEM, concrete, fragility, aging

Procedia PDF Downloads 425

Authors: Şirin Küçük, Ayşe Kök, İsmail Şahin

Abstract:

Mobile devices are very popular and useful tools for assisting people in daily life. With the advancement of mobile technologies, the issue of mobile learning has been widely investigated in education. Many researches consider that it is important to integrate pedagogical and technical strengths of mobile technology into learning environments. For this reason, the purpose of this research is to examine the effect of mobile technology use in education with meta-analysis method. Meta-analysis is a statistical technique which combines the findings of independent studies in a specific subject. In this respect, the articles will be examined by searching the databases for researches which are conducted between 2005 and 2014. It is expected that the results of this research will contribute to future research related to mobile technology use in education.

Keywords: mobile learning, meta-analysis, mobile technology, education

Procedia PDF Downloads 721