Search results for: Chase type friction tester
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7374

Search results for: Chase type friction tester

6654 A Homogeneous Catalytic System for Decolorization of a Mixture of Orange G Acid and Naphthol Blue-Black Dye Based on Hydrogen Peroxide and a Recyclable DAWSON Type Heteropolyanion

Authors: Ouahiba Bechiri, Mostefa Abbessi

Abstract:

The color removal from industrial effluents is a major concern in wastewater treatment. The main objective of this work was to study the decolorization of a mixture of Orange G acid (OG) and naphthol blue black dye (NBB) in aqueous solution by hydrogen peroxide using [H1,5Fe1,5P2W12Mo6O61,23H2O] as catalyst. [H1,5Fe1,5P2 W12Mo6O61,23H2O] is a recyclable DAWSON type heteropolyanion. Effects of various experimental parameters of the oxidation reaction of the dye were investigated. The studied parameters were: the initial pH, H2O2 concentration, the catalyst mass and the temperature. The optimum conditions had been determined, and it was found that efficiency of degradation obtained after 15 minutes of reaction was about 100%. The optimal parameters were: initial pH = 3; [H2O2]0 = 0.08 mM; catalyst mass = 0.05g; for a concentration of dyes = 30mg/L.

Keywords: Dawson type heteropolyanion, naphthol blue-black, dye degradation, orange G acid, oxidation, hydrogen peroxide

Procedia PDF Downloads 341
6653 Robotic Logging Technology: The Future of Oil Well Logging

Authors: Nitin Lahkar, Rishiraj Goswami

Abstract:

“Oil Well Logging” or the practice of making a detailed record (a well log) of the geologic formations penetrated by a borehole is an important practice in the Oil and Gas industry. Although a lot of research has been undertaken in this field, some basic limitations still exist. One of the main arenas or venues where plethora of problems arises is in logistically challenged areas. Accessibility and availability of efficient manpower, resources and technology is very time consuming, restricted and often costly in these areas. So, in this regard, the main challenge is to decrease the Non Productive Time (NPT) involved in the conventional logging process. The thought for the solution to this problem has given rise to a revolutionary concept called the “Robotic Logging Technology”. Robotic logging technology promises the advent of successful logging in all kinds of wells and trajectories. It consists of a wireless logging tool controlled from the surface. This eliminates the need for the logging truck to be summoned which in turn saves precious rig time. The robotic logging tool here, is designed such that it can move inside the well by different proposed mechanisms and models listed in the full paper as TYPE A, TYPE B and TYPE C. These types are classified on the basis of their operational technology, movement and conditions/wells in which the tool is to be used. Thus, depending on subsurface conditions, energy sources available and convenience the TYPE of Robotic model will be selected. Advantages over Conventional Logging Techniques: Reduction in Non-Productive time, lesser energy requirements, very fast action as compared to all other forms of logging, can perform well in all kinds of well trajectories (vertical/horizontal/inclined).

Keywords: robotic logging technology, innovation, geology, geophysics

Procedia PDF Downloads 282
6652 Fabrication of a Potential Point-of-Care Device for Hemoglobin A1c: A Lateral Flow Immunosensor

Authors: Shu Hwang Ang, Choo Yee Yu, Geik Yong Ang, Yean Yean Chan, Yatimah Binti Alias, And Sook Mei Khor

Abstract:

With the high prevalence of Type 2 diabetes mellitus across the world, the morbidities and mortalities associated with Type 2 diabetes have significant impact on the production line for a nation. With routine scheduled clinical visits to manage Type 2 diabetes, diabetic patients with hectic lifestyles can have low clinical compliance. Hence, it often decreases the effectiveness of diabetic management personalized for each diabetic patient. Here, we report a useful developed point-of-care (POC) device that detect glycated hemoglobin (HbA1c, biomarker for long-term Type 2 diabetic management). In fact, the established POC devices certified to be used in clinical setting are not only expensive ($ 8 to $10 per test), they also require skillful practitioners to perform sampling and interpretation. As a paper-based biosensor, the developed HbA1c biosensor utilized lateral flow principle to offer an alternative for cost-effective (approximately $2 per test) and end-user friendly device for household testing. Requiring as little as 2 L of finger-picked blood, the test can be performed at the household with just simple dilution and washings. With visual interpretation of numbers of test lines shown on the developed biosensor, it can be interpreted as easy as a urine pregnancy test, aided with scale of intensity provided. In summary, the developed HbA1c immunosensor has been tested to have high selectivity towards HbA1c, and is stable with reasonably good performance in clinical testing. Therefore, our developed HbA1c immunosensor has high potential to be an effective diabetic management tool to increase patient compliance and thus contain the progression of the diabetes.

Keywords: blood, glycated hemoglobin (HbA1c), lateral flow, type 2 diabetes mellitus

Procedia PDF Downloads 513
6651 The Study of Sintered Wick Structure of Heat Pipes with Excellent Heat Transfer Capabilities

Authors: Im-Nam Jang, Yong-Sik Ahn

Abstract:

In this study sintered wick was formed in a heat pipe through the process of sintering a mixture of copper powder with particle sizes of 100μm and 200μm, mixed with a pore-forming agent. The heat pipe's thermal resistance, which affects its heat transfer efficiency, is determined during manufacturing according to powder type, thickness of the sintered wick, and filling rate of the working fluid. Heat transfer efficiency was then tested at various inclination angles (0°, 45°, 90°) to evaluate the performance of heat pipes. Regardless of the filling amount and test angle, the 200μm copper powder type exhibited superior heat transfer efficiency compared to the 100μm type. After analyzing heat transfer performance at various filling rates between 20% and 50%, it was determined that the heat pipe's optimal heat transfer capability occurred at a working fluid filling rate of 30%. The width of the wick was directly related to the heat transfer performance.

Keywords: heat pipe, heat transfer performance, effective pore size, capillary force, sintered wick

Procedia PDF Downloads 39
6650 Power Quality Improvement Using Interval Type-2 Fuzzy Logic Controller for Five-Level Shunt Active Power Filter

Authors: Yousfi Abdelkader, Chaker Abdelkader, Bot Youcef

Abstract:

This article proposes a five-level shunt active power filter for power quality improvement using a interval type-2 fuzzy logic controller (IT2 FLC). The reference compensating current is extracted using the P-Q theory. The majority of works previously reported are based on two-level inverters with a conventional Proportional integral (PI) controller, which requires rigorous mathematical modeling of the system. In this paper, a IT2 FLC controlled five-level active power filter is proposed to overcome the problem associated with PI controller. The IT2 FLC algorithm is applied for controlling the DC-side capacitor voltage as well as the harmonic currents of the five-level active power filter. The active power filter with a IT2 FLC is simulated in MATLAB Simulink environment. The simulated response shows that the proposed shunt active power filter controller has produced a sinusoidal supply current with low harmonic distortion and in phase with the source voltage.

Keywords: power quality, shunt active power filter, interval type-2 fuzzy logic controller (T2FL), multilevel inverter

Procedia PDF Downloads 155
6649 Non-Destructive Test of Bar for Determination of Critical Compression Force Directed towards the Pole

Authors: Boris Blostotsky, Elia Efraim

Abstract:

The phenomenon of buckling of structural elements under compression is revealed in many cases of loading and found consideration in many structures and mechanisms. In the present work the method and results of dynamic test for buckling of bar loaded by a compression force directed towards the pole are considered. Experimental determination of critical force for such system has not been made previously. The tested object is a bar with semi-rigid connection to the base at one of its ends, and with a hinge moving along a circle at the other. The test includes measuring the natural frequency of the bar at different values of compression load. The lateral stiffness is calculated based on natural frequency and reduced mass on the bar's movable end. The critical load is determined by extrapolation the values of lateral stiffness up to zero value. For the experimental investigation the special test-bed was created that allows the stability testing at positive and negative curvature of the movable end's trajectory, as well as varying the rotational stiffness of the other end connection. Decreasing a friction at the movable end allows extend the diapason of applied compression force. The testing method includes: - Methodology of the experiment planning, that allows determine the required number of tests under various loads values in the defined range and the type of extrapolating function; - Methodology of experimental determination of reduced mass at the bar's movable end including its own mass; - Methodology of experimental determination of lateral stiffness of uncompressed bar rotational semi-rigid connection at the base. For planning the experiment and for comparison of the experimental results with the theoretical values of critical load, the analytical dependencies of lateral stiffness of the bar with defined end conditions on compression load. In the particular case of perfectly rigid connection of the bar to the base, the critical load value corresponds to solution by S.P. Timoshenko. Correspondence of the calculated and experimental values was obtained.

Keywords: non-destructive test, buckling, dynamic method, semi-rigid connections

Procedia PDF Downloads 342
6648 True Single SKU Script: Applying the Automated Test to Set Software Properties in a Global Software Development Environment

Authors: Antonio Brigido, Maria Meireles, Francisco Barros, Gaspar Mota, Fernanda Terra, Lidia Melo, Marcelo Reis, Camilo Souza

Abstract:

As the globalization of the software process advances, companies are increasingly committed to improving software development technologies across multiple locations. On the other hand, working with teams distributed in different locations also raises new challenges. In this sense, automated processes can help to improve the quality of process execution. Therefore, this work presents the development of a tool called TSS Script that automates the sample preparation process for carrier requirements validation tests. The objective of the work is to obtain significant gains in execution time and reducing errors in scenario preparation. To estimate the gains over time, the executions performed in an automated and manual way were timed. In addition, a questionnaire-based survey was developed to discover new requirements and improvements to include in this automated support. The results show an average gain of 46.67% of the total hours worked, referring to sample preparation. The use of the tool avoids human errors, and for this reason, it adds greater quality and speed to the process. Another relevant factor is the fact that the tester can perform other activities in parallel with sample preparation.

Keywords: Android, GSD, automated testing tool, mobile products

Procedia PDF Downloads 289
6647 The Characteristcs and Amino Acid Profile of Edible Coating Extracted from Pigskin Gelatin

Authors: Meity Sompie, Agnes Triasih, Wisje Ponto

Abstract:

Edible coating is thin layers that act as a barrier to the external factors and protect the food products. The addition of the plasticizer to the edible coating is required to overcome film caused by extensive intermolecular forces. The potential development of pigskin with different ages as a raw material for the manufacture of edible films had not been widely publicized. This research was aimed to determine the influence of gelatin concentration and different type of plasticizer on the edible coating characteristics extracted from pigskin gelatin. This study used Completely Randomized Design (CRD) with two factors and three replicates of treatments. The first factor was consisted of pigskin gelatin concentration ( 10, 20, and 30 %) and the second factor was different type of plasticizer (glycerol, sorbitol and PEG). The results show that the interaction between the use of gelatin concentrations and type of plasticizer had significant effect (P< 0.05) on the thickness, tensile strength, elongation, water vapor transmission rate (WVTR), water content and amino acid profile of edible coating. It was concluded that the edible coating from pigskin gelatin with plasticizer gliserol had the best film characteristics, and it can be applied as an edible coating.

Keywords: edible coating, edible film, pigskin gelatin, plasticizer

Procedia PDF Downloads 189
6646 Performences of Type-2 Fuzzy Logic Control and Neuro-Fuzzy Control Based on DPC for Grid Connected DFIG with Fixed Switching Frequency

Authors: Fayssal Amrane, Azeddine Chaiba

Abstract:

In this paper, type-2 fuzzy logic control (T2FLC) and neuro-fuzzy control (NFC) for a doubly fed induction generator (DFIG) based on direct power control (DPC) with a fixed switching frequency is proposed for wind generation application. First, a mathematical model of the doubly-fed induction generator implemented in d-q reference frame is achieved. Then, a DPC algorithm approach for controlling active and reactive power of DFIG via fixed switching frequency is incorporated using PID. The performance of T2FLC and NFC, which is based on the DPC algorithm, are investigated and compared to those obtained from the PID controller. Finally, simulation results demonstrate that the NFC is more robust, superior dynamic performance for wind power generation system applications.

Keywords: doubly fed induction generator (DFIG), direct power control (DPC), neuro-fuzzy control (NFC), maximum power point tracking (MPPT), space vector modulation (SVM), type 2 fuzzy logic control (T2FLC)

Procedia PDF Downloads 398
6645 A Coupled Model for Two-Phase Simulation of a Heavy Water Pressure Vessel Reactor

Authors: D. Ramajo, S. Corzo, M. Nigro

Abstract:

A Multi-dimensional computational fluid dynamics (CFD) two-phase model was developed with the aim to simulate the in-core coolant circuit of a pressurized heavy water reactor (PHWR) of a commercial nuclear power plant (NPP). Due to the fact that this PHWR is a Reactor Pressure Vessel type (RPV), three-dimensional (3D) detailed modelling of the large reservoirs of the RPV (the upper and lower plenums and the downcomer) were coupled with an in-house finite volume one-dimensional (1D) code in order to model the 451 coolant channels housing the nuclear fuel. Regarding the 1D code, suitable empirical correlations for taking into account the in-channel distributed (friction losses) and concentrated (spacer grids, inlet and outlet throttles) pressure losses were used. A local power distribution at each one of the coolant channels was also taken into account. The heat transfer between the coolant and the surrounding moderator was accurately calculated using a two-dimensional theoretical model. The implementation of subcooled boiling and condensation models in the 1D code along with the use of functions for representing the thermal and dynamic properties of the coolant and moderator (heavy water) allow to have estimations of the in-core steam generation under nominal flow conditions for a generic fission power distribution. The in-core mass flow distribution results for steady state nominal conditions are in agreement with the expected from design, thus getting a first assessment of the coupled 1/3D model. Results for nominal condition were compared with those obtained with a previous 1/3D single-phase model getting more realistic temperature patterns, also allowing visualize low values of void fraction inside the upper plenum. It must be mentioned that the current results were obtained by imposing prescribed fission power functions from literature. Therefore, results are showed with the aim of point out the potentiality of the developed model.

Keywords: PHWR, CFD, thermo-hydraulic, two-phase flow

Procedia PDF Downloads 456
6644 Transmission Design That Eliminates Gradual System Problems in Gearboxes

Authors: Ömer Ateş, Atilla Savaş

Abstract:

Reducers and transmission systems are power and speed transfer tools that have been used for many years in the technology world and in all engineering fields. Since today's transmissions have a threaded tap system, torque interruption occurs during tap change. besides, breakdown and manufacturing costs are high. Another problem is the limited torque and rpm setting in stepped gearbox systems. In this study, a new type of transmission system is designed to solve these problems. This new type of transmission system has been called the Continuously Variable Pulley. The most important feature of the transmission system in the study is that it can be adjusted Revolutions Per Minute-wise and torque-wise at the millimeter (precision) adjustment level. In order to make adjustments at this level, an adjustable pulley with the help of hydraulic piston is designed. The efficiency of the designed transmission system is 97 percent, the efficiency of today's transmissions is in the range of 85-95 percent. examined at the analysis and calculations, it is seen that the designed system gives realistic results and can be compared with today's transmissions and reducers. Therefore, this new type of transmission has been proven to be usable in production areas and the world of technology.

Keywords: gearbox, reducer, transmission, torque

Procedia PDF Downloads 111
6643 The Experimental and Numerical Analysis of the Joining Processes for Air Conditioning Systems

Authors: M.St. Węglowski, D. Miara, S. Błacha, J. Dworak, J. Rykała, K. Kwieciński, J. Pikuła, G. Ziobro, A. Szafron, P. Zimierska-Nowak, M. Richert, P. Noga

Abstract:

In the paper the results of welding of car’s air-conditioning elements are presented. These systems based on, mainly, the environmental unfriendly refrigerants. Thus, the producers of cars will have to stop using traditional refrigerant and to change it to carbon dioxide (R744). This refrigerant is environmental friendly. However, it should be noted that the air condition system working with R744 refrigerant operates at high temperature (up to 150 °C) and high pressure (up to 130 bar). These two parameters are much higher than for other refrigerants. Thus new materials, design as well as joining technologies are strongly needed for these systems. AISI 304 and 316L steels as well as aluminium alloys 5xxx are ranked among the prospective materials. As a joining process laser welding, plasma welding, electron beam welding as well as high rotary friction welding can be applied. In the study, the metallographic examination based on light microscopy as well as SEM was applied to estimate the quality of welded joints. The analysis of welding was supported by numerical modelling based on Sysweld software. The results indicated that using laser, plasma and electron beam welding, it is possible to obtain proper quality of welds in stainless steel. Moreover, high rotary friction welding allows to guarantee the metallic continuity in the aluminium welded area. The metallographic examination revealed that the grain growth in the heat affected zone (HAZ) in laser and electron beam welded joints were not observed. It is due to low heat input and short welding time. The grain growth and subgrains can be observed at room temperature when the solidification mode is austenitic. This caused low microstructural changes during solidification. The columnar grain structure was found in the weld metal. Meanwhile, the equiaxed grains were detected in the interface. The numerical modelling of laser welding process allowed to estimate the temperature profile in the welded joint as well as predicts the dimensions of welds. The agreement between FEM analysis and experimental data was achieved.  

Keywords: car’s air–conditioning, microstructure, numerical modelling, welding

Procedia PDF Downloads 393
6642 Heat Transfer in Direct-Driven Generator for Large-Scaled Wind Turbine

Authors: Dae-Gyun Ahn, Eun-Teak Woo, Yun-Hyun Cho, Seung-Ho Han

Abstract:

For the sustainable development of wind energy, energy industries have invested in the development of highly efficient wind generators such as the Axial Flux Permanent Magnet (AFPM) generator. The AFPM generator, however, has a history of overheating on the surface of the stator, so that power production decreases significantly. A proper cooling system, therefore, is needed. Although a convective-type cooling system has been developed, the size of the air blower must be increased when the generator’s capacity exceeds 2.5MW. In this study, a newly developed conductive-type cooling system was proposed for the 2.5MW AFPM generator installed on an offshore wind turbine. Through electromagnetic thermal analysis, the efficiency of the heat transfer on the stator surface was investigated. When using the proposed cooling system, the temperatures on the stator surface and on the permanent magnet under conditions of thermal saturation were 76 and 66 C, respectively. (KETEP 20134030200320)

Keywords: heat transfer, thermal analysis, axial flux permanent magnet, conductive-type cooling system

Procedia PDF Downloads 421
6641 Biomedical Definition Extraction Using Machine Learning with Synonymous Feature

Authors: Jian Qu, Akira Shimazu

Abstract:

OOV (Out Of Vocabulary) terms are terms that cannot be found in many dictionaries. Although it is possible to translate such OOV terms, the translations do not provide any real information for a user. We present an OOV term definition extraction method by using information available from the Internet. We use features such as occurrence of the synonyms and location distances. We apply machine learning method to find the correct definitions for OOV terms. We tested our method on both biomedical type and name type OOV terms, our work outperforms existing work with an accuracy of 86.5%.

Keywords: information retrieval, definition retrieval, OOV (out of vocabulary), biomedical information retrieval

Procedia PDF Downloads 474
6640 Seal Capacity Evaluation by Using Mercury Injection Capillary Pressure Method Integrated with Petrographic Data: A Case Study in Green Dragon Oilfield Offshore Vietnam

Authors: Quoc Ngoc Phan, Hieu Van Nguyen, Minh Hong Nguyen

Abstract:

This study presents an integrated approach using Mercury Injection Capillary Pressure (MICP) and petrographic analysis to assess the seal quality of the inter-bedded shale formations which are considered the intra-formation top seals of hydrocarbon bearing zones in Green Dragon structure. Based on the hydrocarbon column height (HCH) at leak point derived from capillary pressure data, four seal types were identified. Furthermore, the results of scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were interpreted to clarify the influence of clay minerals on seal capacity. The result of the study indicated that the inter-bedded shale formations are the good sealing quality with a majority of analyzed samples ranked type A and B seals in the sample set. Both seal types occurred mainly in mudstones with pore radius estimated less than 0.251 µm. Overall, type A and B seals contained a large amount of authigenic clay minerals such as illite, chlorite which showed the complexity of morphological arrangement in pore space. Conversely, the least common seal type C and D were presented in moderately compacted sandstones with more open pore radius. It is noticeable that there was a reduction of illite and chlorite in clay mineral fraction of these seal type. It is expected that the integrated analysis approach using Mercury Injection Capillary Pressure and petrographic data employed in this study can be applied to assess the sealing quality of future well sites in Green Dragon or other structures.

Keywords: seal capacity, hydrocarbon height column, seal type, SEM, XRD

Procedia PDF Downloads 147
6639 Surface Engineering and Characterization of S-Phase Formed in AISI 304 By Low-Temperature Nitrocarburizing

Authors: Jeet Vijay Sah, Alphonsa Joseph, Pravin Kumari Dwivedi, Ghanshyam Jhala, Subroto Mukherjee

Abstract:

AISI 304 is known for its corrosion resistance which comes from Cr that forms passive Cr₂O₃ on the surface. But its poor hardness makes it unsuitable for applications where the steel also requires high wear resistance. This can be improved by surface hardening using nitrocarburizing processes, which form ε-Fe2-3N, γ’-Fe4N, nitrides, and carbides of Cr and Fe on the surface and subsurface. These formed phases give the surface greater hardness, but the corrosion resistance drops because of the lack of Cr2O3 passivation as a result. To overcome this problem, plasma nitrocarburizing processes are being developed where the process temperatures are kept below 723 K to avoid Cr-N precipitation. In the presented work, low-temperature pulsed-DC plasma nitrocarburizing utilizing a discharge of N₂-H₂-C₂H₂ at 500 Pa with varying N₂:H₂ ratios was conducted on AISI 304 samples at 673 K. The process durations were also varied, and the samples were characterized by microindentation using Vicker’s hardness tester, corrosion resistances were established from electrochemical impedance studies, and corrosion potentials and corrosion currents were obtained by potentiodynamic polarization testing. XRD revealed S-phase, which is a supersaturated solid solution of N and C in the γ phase. The S-phase was observed to be composed of the expanded phases of γ; γN, γC, and γ’N and ε’N phases. Significant improvement in surface hardness was achieved after every process, which is attributed to the S-phase. Corrosion resistance was also found to improve after the processes. The samples were also characterized by XPS, SEM, and GDOES.

Keywords: AISI 304, surface engineering, nitrocarburizing, S-phase

Procedia PDF Downloads 83
6638 Inverted Umbrella-type Chiral Non-coplanar Ferrimagnetic Structure in Co(NO₃)₂

Authors: O. Maximova, I. L. Danilovich, E. B. Deeva, K. Y. Bukhteev, A. A. Vorobyova, I. V. Morozov, O. S. Volkova, E. A. Zvereva, I. V. Solovyev, S. A. Nikolaev, D. Phuyal, M. Abdel-Hafiez, Y. C. Wang, J. Y. Lin, J. M. Chen, D. I. Gorbunov, K. Puzniak, B. Lake, A. N. Vasiliev

Abstract:

The low-dimensional magnetic systems tend to reveal exotic spin liquid ground states or form peculiar types of long-range order. Among systems of vivid interest are those characterized by the triangular motif in two dimensions. The realization of either ordered or disordered ground state in a triangular, honeycomb, or kagome lattices is are dictated by the competition of exchange interactions, also being sensitive to anisotropy and the spin value of magnetic ions. While the low-spin Heisenberg systems may arrive at a spin liquid long-range entangled quantum state with emergent gauge structures, the high-spin Ising systems may establish the rigid non-collinear structures. This study presents the case of chiral non-coplanar inverted umbrella-type ferrimagnet formed in cobalt nitrate Co(NO₃)₂ below T

Keywords: chiral magnetic structures, low dimensional magnetic systems, umbrella-type ferrimagnets, chiral non-coplanar magnetic structures

Procedia PDF Downloads 107
6637 Dynamic Test for Stability of Bar Loaded by a Compression Force Directed Towards the Pole

Authors: Elia Efraim, Boris Blostotsky

Abstract:

The phenomenon of buckling of structural elements under compression is revealed in many cases of loading and found consideration in many structures and mechanisms. In the present work the method and results of dynamic test for buckling of bar loaded by a compression force directed towards the pole are considered. Experimental determination of critical force for such system has not been made previously. The tested object is a bar with semi-rigid connection to the base at one of its ends, and with a hinge moving along a circle at the other. The test includes measuring the natural frequency of the bar at different values of compression load. The lateral stiffness is calculated based on natural frequency and reduced mass on the bar's movable end. The critical load is determined by extrapolation the values of lateral stiffness up to zero value. For the experimental investigation the special test-bed was created that allows the stability testing at positive and negative curvature of the movable end's trajectory, as well as varying the rotational stiffness of the other end connection. Decreasing a friction at the movable end allows extend the diapason of applied compression force. The testing method includes : - methodology of the experiment planning, that allows determine the required number of tests under various loads values in the defined range and the type of extrapolating function; - methodology of experimental determination of reduced mass at the bar's movable end including its own mass; - methodology of experimental determination of lateral stiffness of uncompressed bar rotational semi-rigid connection at the base. For planning the experiment and for comparison of the experimental results with the theoretical values of critical load, the analytical dependencies of lateral stiffness of the bar with defined end conditions on compression load. In the particular case of perfectly rigid connection of the bar to the base, the critical load value corresponds to solution by S.P. Timoshenko. Correspondence of the calculated and experimental values was obtained.

Keywords: buckling, dynamic method, end-fixity factor, force directed towards a pole

Procedia PDF Downloads 333
6636 Water Irrigation in the Chlef Region Using Photovoltaic Solar Energy

Authors: T. Tahri, H. Zahloul, K. E. Meddah, H. Lazergue

Abstract:

This paper presents a theoretical study that leads to the design of a photovoltaic pumping system to irrigate six hectares of oranges in the valley of Chlef using the software "PVSYST". It was shown that the site of Chlef presents a favorable climate to this type of energy with an irradiation of over 5 kWh/m2/day, and significant resources underground water. Another very important coincidence still promotes the use of this type of energy for pumping water in Chlef is that the demand for water, especially in agriculture, peaked in hot and dry where it is precisely when one has access to the maximum of solar energy.

Keywords: solar energy, irradiation, water pumping, design, Valley of Chlef

Procedia PDF Downloads 237
6635 Numerical Study for Spatial Optimization of DVG for Fin and Tube Heat Exchangers

Authors: Amit Arora, P. M. V. Subbarao, R. S. Agarwal

Abstract:

This study attempts to find promising locations of upwash delta winglets for an inline finned tube heat exchanger. Later, location of winglets that delivers highest improvement in thermal performance is identified. Numerical results clearly showed that optimally located upwash delta winglets not only improved the thermal performance of fin area in tube wake and tubes, but also improved overall thermal performance of heat exchanger.

Keywords: apparent friction factor, delta winglet, fin and tube heat exchanger, longitudinal vortices

Procedia PDF Downloads 289
6634 Review for Mechanical Tests of Corner Joints on Wooden Windows and Effects to the Stiffness

Authors: Milan Podlena, Stepan Hysek, Jiri Prochazka, Martin Bohm, Jan Bomba

Abstract:

Corner joints are the weakest part of windows, where the members are connected together. Since the dimensions of the windows started become bigger, the strength requirements for corner joints started to increase as well. Therefore, the aim of this study was to test the samples of corner joints of wooden windows. Moisture content of test specimens was stabilized in the climate chamber. After conditioning, test specimens were loaded in the laboratory conditions onto an universal testing machine and the failure load was measured. Data was recalculated by using goniometric, bending moment and stiffness equation to the stiffness coefficients and the bending moments were investigated. The results showed difference that was observed for the mortise with tenon joint and the dowel joint. This difference was explained by a varied adhesive bond area, which is related to the dimensions of dowels (diameter and length) as well. The bending moments and stiffness ware (except of type of corner joint) also affected by type of used adhesive, type of dowels and wood species.

Keywords: corner joint, wooden window, bending moment, stiffness

Procedia PDF Downloads 201
6633 Experimental and FEA Study for Reduction of Damage in Sheet Metal Forming

Authors: Amitkumar R. Shelar, B. P. Ronge, Sridevi Seshabhattar, R. M. Wabale

Abstract:

This paper gives knowledge about the behavior of cold rolled steel IS 513_2008 CR2_D having grade D for the reduction of ductile damage. CR specifies Cold Rolled and D for Drawing grade. Problems encountered during sheet metal forming operations are dent, wrinkles, thinning, spring back, insufficient stretching etc. In this paper, wrinkle defect was studied experimentally and by using FE software on one of the auto components due to which its functionality was decreased. Experimental result and simulation result were found to be in agreement.

Keywords: deep drawing, FE software-LS DYNA, friction, wrinkling

Procedia PDF Downloads 474
6632 Functional Compounds Activity of Analog Rice Based on Purple Yam and Bran as Alternative Food for People with Diabetes Mellitus Type II

Authors: A. Iqbal Banauaji, Muchamad Sholikun

Abstract:

Diabetes mellitus (DM) is a metabolism disorder that tends to increase its prevalence in the world, including in Indonesia. The development of DM type 2 can cause oxidative stress characterized by an imbalance between oxidants and antioxidants in the body Increased oxidative stress causes type 2 diabetes mellitus to require intake of exogenous antioxidants in large quantities to inhibit oxidative damage in the body. Bran can be defined as a functional food because it consists of 11.39% fiberand 28.7% antioxidants and the purple yam consists of anthocyanin which functions as an antioxidant. With abundant amount and low price, purple yam and bran can be used for analog rice as the effort to diversify functional food. The antioxidant’s activity of analog rice from purple yam and bran which is measured by using DPPH’s method is 12,963%. The rough fiber’s level on the analog rice from purple yam is 2.985%. The water amount of analog rice from purple yam and bran is 8.726%. Analog rice from purple yam and bran has the similar texture as the usual rice, tasted slightly sweet, light purple colored, and smelled like bran.

Keywords: antioxidant, analog rice, functional food, diabetes mellitus

Procedia PDF Downloads 172
6631 Features of Normative and Pathological Realizations of Sibilant Sounds for Computer-Aided Pronunciation Evaluation in Children

Authors: Zuzanna Miodonska, Michal Krecichwost, Pawel Badura

Abstract:

Sigmatism (lisping) is a speech disorder in which sibilant consonants are mispronounced. The diagnosis of this phenomenon is usually based on the auditory assessment. However, the progress in speech analysis techniques creates a possibility of developing computer-aided sigmatism diagnosis tools. The aim of the study is to statistically verify whether specific acoustic features of sibilant sounds may be related to pronunciation correctness. Such knowledge can be of great importance while implementing classifiers and designing novel tools for automatic sibilants pronunciation evaluation. The study covers analysis of various speech signal measures, including features proposed in the literature for the description of normative sibilants realization. Amplitudes and frequencies of three fricative formants (FF) are extracted based on local spectral maxima of the friction noise. Skewness, kurtosis, four normalized spectral moments (SM) and 13 mel-frequency cepstral coefficients (MFCC) with their 1st and 2nd derivatives (13 Delta and 13 Delta-Delta MFCC) are included in the analysis as well. The resulting feature vector contains 51 measures. The experiments are performed on the speech corpus containing words with selected sibilant sounds (/ʃ, ʒ/) pronounced by 60 preschool children with proper pronunciation or with natural pathologies. In total, 224 /ʃ/ segments and 191 /ʒ/ segments are employed in the study. The Mann-Whitney U test is employed for the analysis of stigmatism and normative pronunciation. Statistically, significant differences are obtained in most of the proposed features in children divided into these two groups at p < 0.05. All spectral moments and fricative formants appear to be distinctive between pathology and proper pronunciation. These metrics describe the friction noise characteristic for sibilants, which makes them particularly promising for the use in sibilants evaluation tools. Correspondences found between phoneme feature values and an expert evaluation of the pronunciation correctness encourage to involve speech analysis tools in diagnosis and therapy of sigmatism. Proposed feature extraction methods could be used in a computer-assisted stigmatism diagnosis or therapy systems.

Keywords: computer-aided pronunciation evaluation, sigmatism diagnosis, speech signal analysis, statistical verification

Procedia PDF Downloads 283
6630 Binder-Free Porous Photocathode Based on Cuprous Oxide for High-Performing P-Type Dye-Sensitized Solar Cells

Authors: Marinela Miclau, Melinda Vajda, Nicolae Miclau, Daniel Ursu

Abstract:

Characterized by a simple structure, easy and low cost fabrication, the dye-sensitized solar cell (DSSC) attracted the interest of the scientific community as an attractive alternative of conventional Si-based solar cells and thin-film solar cells. Over the past 20 years, the main efforts have attempted to enhance the efficiency of n-type DSSCs, the highest efficiency record of 14.30% was achieved using the co-sensitization of two metal-free organic dyes and Co (II/III) tris(phenanthroline)-based redox electrolyte. In the last years, the development of the efficient p-type DSSC has become a research focus owing to the fact that the concept of tandem solar cell was proposed as the solution to increase the power conversion efficiency. A promising alternative for the photocathodes of p-type DSSC, cuprous (Cu2O) and cupric (CuO) oxides have been investigated because of its nontoxic nature, low cost, high natural abundance, a good absorption coefficient for visible light and a higher dielectric constant than NiO. In case of p-type DSSC based on copper oxides with I3-/I- as redox mediator, the highest conversion efficiency of 0.42% (Cu2O) and 0.03% (CuO) has achieved. Towards the increase in the performance, we have fabricated and analyzed the performance of p-type DSSC prepared with the binder-free porous Cu2O photocathodes. Porous thin film could be an attractive alternative for DSSC because of their large surface areas which enable the efficient absorption of the dyes and light. We propose a simple and one-step hydrothermal method for the preparation of porous Cu2O thin film using copper substrate, cupric acetate and ethyl cellulose. The cubic structure of Cu2O has been determined by X-ray diffraction (XRD) and porous morphology of thin film was emphasized by Scanning Electron Microscope Inspect S (SEM). Optical and Mott-Schottky measurements attest of the high quality of the Cu2O thin film. The binder-free porous Cu2O photocathode has confirmed the excellent photovoltaic properties, the best value reported for p-type DSSC (1%) in similar conditions being reached.

Keywords: cuprous oxide, dye-sensitized solar cell, hydrothermal method, porous photocathode

Procedia PDF Downloads 153
6629 Comparison for Some Elastic and Mechanical Properties of Plutonium Dioxide

Authors: M. Guler, E. Guler

Abstract:

We report some elastic parameters of cubic fluorite type neptunium dioxide (NpO2) with a recent EAM type interatomic potential through geometry optimization calculations. Typical cubic elastic constants, bulk modulus, shear modulus, young modulus and other relevant elastic parameters were also calculated during research. After calculations, we have compared our results with the available theoretical data. Our results agree well with the previous theoretical findings of the considered quantities of NpO2.

Keywords: NpO2, elastic properties, bulk modulus, mechanical properties

Procedia PDF Downloads 318
6628 Effects of Resistance Exercise Training on Blood Profile and CRP in Men with Type 2 Diabetes Mellitus

Authors: Mohsen Salesi, Seyyed Zoheir Rabei

Abstract:

Exercise has been considered a cornerstone of diabetes prevention and treatment for decades, but the benefits of resistance training are less clear. The purpose of this study was to determine the impact of resistance training on blood profile and inflammatory marker (CRP) of type 2 diabetes mellitus people. Thirty diabetic male were recruited (age: 50.34±10.28 years) and randomly assigned to 8 weeks resistance exercise training (n=15) and control groups (n=15). Before and after training blood pressure, weight, lipid profile (TC, TG, LDL-c, and HDL-c) and hs-CRP were measured. The resistance exercise training group took part in supervised 50–80 minutes resistance training sessions, three days a week on non-consecutive days for 8 weeks. Each exercise session included approximately 10 min of warm-up and cool-down periods. Results showed that TG significantly decreased (pre 210.19±9.31 vs. 101.12±7.25, p=0.03) and HDL-c significantly increased (pre 42.37±3.15 vs. 47.50±2.19, p=0.01) after exercise training. However, there was no difference between groups in TC, LDL-c, BMI and weight. In addition, a decrease in fasting blood glucose levels showed significant difference between groups (pre 144.65±5.73 vs. 124.21±6.48 p=0.04). Regular resistance exercise training can improve the lipid profile and reducing the cardiovascular risk factors in T2DM patients.

Keywords: lipid profile, resistance exercise, type 2 diabetes mellitus, men

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6627 [Keynote Talk]: Treatment Satisfaction and Safety of Sitagliptin versus Pioglitazone in Patients with Type 2 Diabetes Mellitus Inadequately Controlled on Metformin Monotherapy

Authors: Shahnaz Haque, Anand Shukla, Sunita Singh, Anil Kem

Abstract:

Introduction: Diabetes Mellitus is a chronic metabolic disease affecting millions worldwide. Metformin is the most commonly prescribed first line oral hypoglycemic drug for type 2 diabetes mellitus, but due to progressive worsening of blood glucose control during the natural history of type 2 diabetes, combination therapy usually becomes necessary. Objective: This study was designed to assess the treatment satisfaction between Sitagliptin versus Pioglitazone added to Metformin in patients with type 2 diabetes mellitus (T2DM). Methods: We conducted a prospective, open label, randomized, parallel group study in SIMS, Hapur, U.P. Eligible patients fulfilling inclusion criteria were randomized into two groups having 25 patients in each group using tab Sitagliptin 100mg, tab Pioglitazone 30mg added to ongoing tab Metformin (500mg) therapy for 16 weeks. The follow-up visits were on weeks 4,12 and 16. Result: 16 weeks later, addition of Sitagliptin 100mg compared to that of Pioglitazone 30 mg to ongoing Metformin therapy provided similar glycosylated hemoglobin (HbA1c) lowering efficacy in patients with T2DM with inadequate glycemic control on metformin monotherapy. Change in HbA1c in group1 was -0.656±0.21%(p<0.0001) whereas in group2 was -0.748±0.35%(p<0.0001). Hence decrease in HbA1c from baseline was more in group2. Both treatments were well tolerated with negligible risk of hypoglycaemia. Weight loss was observed with Sitagliptin in contrast to weight gain seen in Pioglitazone. Conclusion: In this study, Sitagliptin 100 mg along with metformin therapy in comparison to pioglitazone 30 mg plus metformin therapy was both effective, well-tolerated and improved glycemic control in both the groups. Addition of pioglitazone had cause oedema and weight gain to the patients whereas sitagliptin caused weight loss in its patients.

Keywords: sitagliptin, pioglitazone, metformin, type 2 diabetes mellitus

Procedia PDF Downloads 288
6626 Simulated Microgravity Inhibits L-Type Calcium Channel Currents by Up-Regulation of miR-103 in Osteoblasts

Authors: Zhongyang Sun, Shu Zhang

Abstract:

In osteoblasts, L-type voltage sensitive calcium channels (LTCCs), especially the Cav1.2 LTCCs, play fundamental roles in cellular responses to external stimuli including both mechanical forces and hormonal signals. Several lines of evidence have revealed that the density of bone is increased and the resorption of bone is decreased when these calcium channels in osteoblasts are activated. And numerous studies have shown that mechanical loading promotes bone formation in the modeling skeleton, whereas removal of this stimulus in microgravity results in a reduction in bone mass. However, the effect of microgravity on LTCCs in osteoblasts is still unknown. The aim of this study was to determine whether microgravity exerts influence on LTCCs in osteoblasts and the possible mechanisms underlying. In this study, we demonstrate that simulated microgravity substantially inhibits LTCCs in osteoblast by suppressing the expression of Cav1.2. Then we show that the up-regulation of miR-103 is involved in the down-regulation of Cav1.2 expression and inhibition of LTCCs by simulated microgravity in osteoblasts. Our study provides a novel mechanism of simulated microgravity-induced adverse effects on osteoblasts, offering a new avenue to further investigate the bone loss caused by microgravity.

Keywords: L-type voltage sensitive calcium channels, Cav1.2, osteoblasts, microgravity

Procedia PDF Downloads 289
6625 Influence of Alcohol to Quality Iota Type Carrageenan

Authors: Andi Hasizah Mochtar, Meta Mahendradatta, Amran Laga, Metusalach Metusalach, Salengke Salengke, Mariati Bilang, Andi Amijoyo Mochtar, Reta Reta, Aminah Muhdar, Sri Suhartini

Abstract:

This study aims to determine the effect of alcohol type on the quality of iota carrageenan-based on extraction technology through the application of ohmic reactor. Results of this analysis will be used as a reference for selecting the proper type of alcohol used for carrageenan precipitated after extraction by technology based ohmic. The results of analysis performed included analysis of viscosity, gel strength, and yield of iota carrageenan. Viscosity is the highest obtained at precipitated by using isopropyl alcohol with an average of 291.5 Cp (at 160 rpm), then with methanol at an average of 282 Cp, then precipitated by using ethanol at an average of 206.5 Cp. Gel strength is the lowest obtained 67.74 on precipitated by using ethanol, then an average of 74.34 in precipitated that using methanol, and the highest average of 80.11 in precipitated that using isopropyl alcohol.

Keywords: extraction of carrageenan, gel strength, ohmic technology, precipitated, seaweed (Eucheuma spinosum), viscosity

Procedia PDF Downloads 202