319 research outputs found

    PWM control techniques for three phase three level inverter drives

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    In this paper two very efficient pulse width modulation techniques were discussed named Sin pulse width modulation and space vector pulse width modulation. The basic structure of the three-level inverter neutral-point clamped is introduced and the basic idea about space vector pulse width modulation for three-level voltage source inverter has been discussed in detail. Nearest three vectors space vector pulse width modulation control algorithm is adopted as the control strategy for the three phase three level NPC inverter in order to compensate the neutral-point shifting. Mathematical formulation for calculating switching sequence has determined. Comparative analysis proving superiority of the space vector pulse width modulation technique over the conventional pulse width modulation, and the results of the simulations of inverter confirm the feasibility and advantage of the space vector pulse width modulation strategy over sin pulse width modulation in terms of good utilization of dc-bus voltage, low current ripple and reduced switching frequency. Space vector pulse width modulation provides advantages better fundamental output voltage and useful in improving harmonic performance and reducing total harmonic distortion

    A Register Used In Barclays Premier League Official Page Of Instagram By Sociolinguistic Perspective

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    This research aimed (1) to describe the Linguistic Forms of the register in Barclays Premier League official page (2) to describe the meaning of each Register in Barclays Premier League official page in instagram. The type of this research uses descriptive qualitative. The data source of this research is taken from Barclays Premier League of istagram official page. The data of this Research are the comments of the photo of instagram. The researcher collects data using documentation technique. The researcher analyzed data in two steps, classifying data as word, phrase, noun phrase, verb phrase and adjective, determining the meaning of register by Halliday’s “speaking” theory. The results of the study shows that the linguistic forms of the data are (A) Noun (86.6%) (B) Adjective (6,66%) (C) Verb(6,66%) (D) Adverbial Phrase of Time (6,66%) and the researcher found the intention of the register used in Barclays Premier League refers to place, time, cause and purpose

    Rancang Bangun Aplikasi Game Puzzle Berbasis Android Menggunakan Algoritma Decision Tree

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    The development of games today is very rapid and has become part of the lifestyle. A puzzle game is an application that can be used to hone thinking and memory skills where users have to find a way out and collect special items that have been provided at every level of the game . The player must collect all the white orb in each level to get the key to move to the next level but the player will be confronted by the constraints on how to find the key and retrieve it . The game is designed using decision tree and game algorithms designed using Game Maker Studio that is applied to Android devices

    Numerical Investigation of Heat Transfer Enhancement in a Circular Tube with Rectangular Opened Rings

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    Turbulent forced convection of coolant air flow (10 m/s velocity) in a steel tube of 50 cm long having outside diameter of 60 mm and inside diameter of 30 mm with constant outside surface temperature of 1000, 1200 and 1400 Ko is numerically analyzed. The renormalization group k-ε model is used to simulate turbulence in ANSYS - FLUENT 14.5. An opened ring of rectangular cross section (5x7 mm) is fitted in the tube and separated by 8cm pitch. Results of temperature and velocity distribution along the tube center line for the case of tube with internal ribs were compared with that of plain tube , these results show that the use of internal ribs enhance the heat transfer rate and found to possess the highest performance factors for turbulent flow

    Effect of adding Garlic Powder (Allium sativum) and Black Seed ( Nigella sativa) in Feed on Broiler Growth Performance and Intestinal Wall Structure

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    This study was conducted to investigate the effect of garlic powder (GP) black seed (BS) and plant premix (GP and BS) in feed on broiler growth and intestinal wall structure. The result included 480 Hubbard broiler chicks( day-old) There were 4 treatment groups each consisting of 3 replicates .The four dietary treatments consisted of a control ( basal diet ) , basal diet + 0.5% GP , basal diet +0.5% BS and basal diet +0.5% plant premix (GP and BS) , to the starter and finisher diet. The experiment lasted 42 days. Body weight , body weight gain , feed intake and feed conversion ratio were determined weekly and intestinal characteristics were determined at the end of the study (42 day) .The addition of GP and BS plant premix (GP and BS) to the diet resulted in significantly higher body weight , body weight gain and feed intake as compared to that of control group. However , feed conversion ratio was not influenced by dietary treatment (p>0.05) . The villus height , crypt depth and crypt depth to villus height ratio was significantly higher in group garlic powder and plant premix (GP and BS) than other groups. While villus height , crypt depth and crypt depth to villus height ratio significantly lower in the control group compared with other treatment groups. It was found that the goblet cell were not affected by any treatment . Based on the results of this study it be could be advised to supplement broiler feed with 0.5% GP and plant premix. Key words: Garlic , Black seed, Performance, wall intestinal structure

    miRNA in the Regulation of Skeletal Muscle Adaptation to Acute Endurance Exercise in C57Bl/6J Male Mice

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    MicroRNAs (miRNAs) are evolutionarily conserved small non-coding RNA species involved in post-transcriptional gene regulation. In vitro studies have identified a small number of skeletal muscle-specific miRNAs which play a crucial role in myoblast proliferation and differentiation. In skeletal muscle, an acute bout of endurance exercise results in the up-regulation of transcriptional networks that regulate mitochondrial biogenesis, glucose and fatty acid metabolism, and skeletal muscle remodelling. The purpose of this study was to assess the expressional profile of targeted miRNA species following an acute bout of endurance exercise and to determine relationships with previously established endurance exercise responsive transcriptional networks. C57Bl/6J wild-type male mice (N = 7/group) were randomly assigned to either sedentary or forced-endurance exercise (treadmill run @ 15 m/min for 90 min) group. The endurance exercise group was sacrificed three hours following a single bout of exercise. The expression of miR- 181, 1, 133, 23, and 107, all of which have been predicted to regulate transcription factors and co-activators involved in the adaptive response to exercise, was measured in quadriceps femoris muscle. Endurance exercise significantly increased the expression of miR-181, miR-1, and miR-107 by 37%, 40%, and 56%, respectively, and reduced miR-23 expression by 84% (P≤0.05 for all), with no change in miR-133. Importantly, decreased expression of miRNA-23, a putative negative regulator of PGC-1α was consistent with increased expression of PGC-1α mRNA and protein along with several downstream targets of PGC-1α including ALAS, CS, and cytochrome c mRNA. PDK4 protein content remains unaltered despite an increase in its putative negative regulator, miR-107, and PDK4 mRNA expression. mRNA expression of miRNA processing machinery (Drosha, Dicer, and DGCR8) remained unchanged. We conclude that miRNA-mediated post-transcriptional regulation is potentially involved in the complex regulatory networks that govern skeletal muscle adaptation to endurance exercise in C57Bl/6J male mice

    LIGHTWEIGHT CRYPTOGRAPHY METHOD IN THE INTERNET OF THINGS USING ELLIPTIC CURVE AND CROW SEARCH ALGORITHM

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    The Internet of Things (IoT) as an important technology consists of a heterogeneous and huge number of devices that generates an enormous amount of data in various applications. However, generating and transmitting huge amount of data in the IoT makes it crucial to implement a secure and safe data transmission scheme. Cryptography methods can secure the confidentiality, data integrity, access control, and authentication. Due to constrained resources in IoT devices, providing classical cryptography schemes isn’t efficient for IoT applications, so a lightweight cryptography scheme is one of the most important solutions to overcome security challenges in IoT. In this paper, a new security scheme called ECCCSASHA256 based on Elliptic Curve Cryptography (ECC) and Secure Hash Algorithm (SHA-256) using Crow Search Algorithm (CSA) has been proposed for secure data transmission in IoT devices. The ECCCSASHA256 model uses the CSA for generating a private key to encode the elliptic curve. Furthermore, the proposed scheme uses SHA-256 model for hashing the incoming encoded data using ECC. The simulation results indicate that the average throughput of the proposed model was about 8.22% and 8.97% higher in encryption and 8.72% and 9.81% higher in decryption compared to 3DES&ECC&SHA-256 and RC4&ECC&SHA-256, respectively

    Perbandingan Unjuk Kerja Resin Penukar Ion Basa Kuat Dowex Marathon A dengan Purolite pada Proses Pemurnian Biogas Skala Pilot Plant

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    Adsorption of carbon dioxide is a vital process in biogas purification. A previous study has narrowed down the choice of ion exchange resins for the adsorption process into two commercial resins, Dowex Marathon A, and Purolite. Dowex Marathon A boasts the advantage of having no need of any pretreatments to use. Purolite, although needing pretreatment before USAge, costs only roughly a third of Dowex Marathon A. The objective of the study is to decide on which resin is best suited to commercially produce biogas free from pollutants, most of which is carbon dioxide. Both resins at their fresh state were tested for durability by checking on levels of carbon dioxide content at set time intervals. Results suggest the Purolite resin to be more durable than the Dowex Marathon A resin. Data of gas passing through Dowex showed relatively high concentration of CO2 after 10 minutes of operation. While Purolite showed its first signs of CO2 after 20 minutes of operation. Further tests are conducted to compare fresh and regenerated Pirolite resins. Comparison between fresh and postregeneration Purolite showed relatively consistent results where the regenerated resin showed its first signs of CO2 after 25 minutes
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