فیلترها/جستجو در نتایج    

فیلترها

سال

بانک‌ها




گروه تخصصی











متن کامل


اطلاعات دوره: 
  • سال: 

    2019
  • دوره: 

    32
  • شماره: 

    4 (TRANSACTIONS A: Basics)
  • صفحات: 

    510-518
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    195
  • دانلود: 

    0
چکیده: 

We have developed the effective algorithm for detecting digital binary PHASE-shift keyed signals. This algorithm requires a small number of arithmetic operations over the signal period. It can be relat ively easy implemented based on the modern programmable logic devices. It also provides high interference immunity by identifying signal presence when signal-to-noise ratio is much less that its working value in the receiving path. The introduced DETECTOR has int rinsic frequency selectivity and allows us to form the est imate of the noise level to realize the adaptive determination of decision threshold. In order to get confirmation of the DETECTOR operability and performance, we suggest the expressions for false alarm and missing probabilities. In addit ion, we have examine, both theoretically and experimentally, the influence of the DETECTOR parameters on its characterist ics.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 195

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسندگان: 

MANNAMA V. | PAAVLE T.

اطلاعات دوره: 
  • سال: 

    2000
  • دوره: 

    -
  • شماره: 

    -
  • صفحات: 

    119-122
تعامل: 
  • استنادات: 

    1
  • بازدید: 

    119
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 119

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 1 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسندگان: 

NASIR GH. | AL ARAJI S.R.

اطلاعات دوره: 
  • سال: 

    2009
  • دوره: 

    1
  • شماره: 

    3
  • صفحات: 

    45-51
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    284
  • دانلود: 

    0
چکیده: 

This work introduces a new structure of Zero Crossing Digital PHASE Locked Loop with Arc Sine block (ASZCDPLL) to linearize the PHASE difference detection, and enhance the loop performance. The new loop has faster acquisition, less steady state PHASE error, and wider locking range as compared to the conventional ZCDPLL. The locking range improvement and faster acquisition have been confirmed through simulation. The loop has been implemented and tested in real time using Texas Instruments TMS320C6416 DSP development kit.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 284

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
نویسندگان: 

GHOLAMI M.

اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    29
  • شماره: 

    7 (TRANSACTIONS A: Basics)
  • صفحات: 

    916-920
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    197
  • دانلود: 

    0
چکیده: 

In this paper a new PHASE-frequency DETECTOR is proposed using transmission gates which can detect PHASE difference less than 500ps. In other word, the proposed PHASE-frequency DETECTOR (PFD) can work in frequencies higher than 1. 7 GHz, whereas a conventional PFD operates at frequencies less than 1. 1 GHz. This new architecture is designed in TSMC 0. 13um CMOS Technology. Also, the proposed PFD achieves a capture range approximately twice that of conventional PFDs. The simulation results support the theoretical predictions. To validate correct performance of this novel PFD, it is then used in a conventional delay locked loop structure.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 197

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسندگان: 

GHOLAMI M. | Binaei R. | Gholamnia Roshan M.

اطلاعات دوره: 
  • سال: 

    2020
  • دوره: 

    33
  • شماره: 

    2 (TRANSACTIONS B: Applications)
  • صفحات: 

    269-276
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    199
  • دانلود: 

    0
چکیده: 

The electronic industry has grown vastly in recent years, and researchers are trying to minimize circuits delay, occupied area and power consumption as much as possible. In this regard, many technologies have been introduced. Quantum Cellular Automata (QCA) is one of the schemes to design nano-scale digital electronic circuits. This technology has high speed and low power consumption, and occupies very little area. PHASE-locked loops (PLLs) and delay-locked loops (DLLs) are blocks that are commonly used in telecommunication applications. One of the most important parts in DLL and PLL is the PHASE-frequency DETECTOR. Therefore, the design of this circuit in QCA technology is of great importance. In this paper, two new PHASE-frequency DETECTORs sensitive to falling and rising edge have been introduced in QCA technology. Both of the designs are composed of 104 cells; occupy only 0. 13 μ m2 of an area and 1. 5 QCA clock cycles latency. The designs are in one layer and all the inputs and outputs are available to be used by another circuit.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 199

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسندگان: 

GHOLAMI M. | ARDESHIR G.

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    27
  • شماره: 

    4 TRANSACTIONS A: BASICS
  • صفحات: 

    517-521
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    356
  • دانلود: 

    0
چکیده: 

In this paper a new architecture for delay locked loops is proposed. Static PHASE offset and reset path delay are the most important problems in PHASE-frequency DETECTORs (PFD). The proposed structure decreases the jitter resulted from PFD by switching two PFDs. In this new architecture, a conventional PFD is used before locking of DLL to decrease the amount of PHASE difference between input and output of the DLL. Near locking, an XOR gate is used to act as a PFD which makes the DLL locks with less jitter. Also, the reset path time and glitch are decreased by using the XOR gate. The proposed architecture has been designed in TSMC 0.18um CMOS Technology. The simulation results support the theoretical design aspects.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 356

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
اطلاعات دوره: 
  • سال: 

    1399
  • دوره: 

    50
  • شماره: 

    4 (پیاپی 94)
  • صفحات: 

    1485-1497
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    180
  • دانلود: 

    81
چکیده: 

افزایش سرعت، دقت و کاهش توان مصرفی ادوات الکترونیکی، پارامترهای مهمی هستند که در طراحی و تولید این ادوات باید مورد توجه قرار بگیرند. در این مقاله، طراحی یک حلقه قفل شونده در فاز بهبود یافته با استفاده از ترانزیستورهای مبتنی بر نانو لوله کربنی ارایه شده است. با استفاده از یک ساختار تفاضلی در نوسان ساز حلقوی، نویز حاصل از منبع تغذیه و همچنین زیرلایه حذف می گردد. همچنین به کارگیری سلف فعال در این نوسان ساز موجب افزایش قابل توجه فرکانس نوسان می گردد. در مدار آشکارساز فاز ارایه شده، با استفاده از یک ساختار جدید حلقه-باز، سرعت آشکارسازی به میزان قابل توجهی افزایش می یابد. این امر موجب حذف مدار تقسیم کننده در مسیر حلقه می گردد. با حذف مدار تقسیم کننده، نویز مدار به میزان قابل توجهی کاهش خواهد یافت. مدار طراحی شده، یک بار با استفاده از تکنولوژی ماسفت در پروسه 0. 18 میکرومتر و درنهایت با ترانزیستورهای اثر میدانی مبتنی بر نانولوله کربنی در پروسه ی32 نانومتر و با منبع تغذیه ی 0. 9 ولت، پیاده سازی شده است. فرکانس مرکزی در این پروسه برابر با 68. 5 گیگاهرتز می باشد؛ همچنین توان مصرفی کمتر از 150 نانو وات و زمان قفل شدن آن کمتر از 10 پیکوثانیه می باشد.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 180

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 81 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسنده: 

طاهری علی

اطلاعات دوره: 
  • سال: 

    1393
  • دوره: 

    21
تعامل: 
  • بازدید: 

    277
  • دانلود: 

    142
چکیده: 

لطفا برای مشاهده چکیده به متن کامل (pdf) مراجعه فرمایید.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 277

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 142
نویسنده: 

DALALI NASSER | PARANDI KHATEREH

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    20
تعامل: 
  • بازدید: 

    170
  • دانلود: 

    0
چکیده: 

SOLID PHASE MICROEXTRACTION AS A SOLVENT FREE SAMPLE PREPARATION TECHNIQUE INVENTED BY PAWLISZYN AND CO-WORKERS IN 1990 [1], HAS ATTRACTED THE EYE BALL OF MANY RESEARCHERS IN DIFFERENT FIELDS DURING THE PAST FEW YEARS. ONE OF THE MAIN EFFORTS IS DEVOTED TO THE INTRODUCTION AND APPLICATION OF NOVEL FIBRE COATINGS. IONIC LIQUIDS IS ONE OF THE CONCERNED MATERIALS FOR THIS PURPOSE [2].METHADONE IS A SYNTHETIC OPIATE. IN MANY COUNTRIES IT IS USED FOR SUBSTITUTION THERAPY OF HEROIN ADDICTION. AS A RESULT OF THE VERY LIBERAL PRESCRIPTION PRACTICE IT GETS INTO THE DRUG SCENE AND IS ABUSED ALSO BY OTHER PERSONS LEADING TO SEVERE INTOXICATIONS AND METHADONE FATALITIES [3]. METHADONE WAS FIRST USED TO TREAT HEROIN ADDICTS IN 1965 IN UNITED STATES AND IN 1966 IN EUROPE (SWEDEN), AND IT IS STILL USED IN IRAN AS ONE OF THE MAIN APPLICABLE THERAPY SUBSTITUENT.HENCE ITS MONITORING IN BIOLOGICAL OR PHARMACEUTICAL SAMPLES IS IMPORTANT CONSIDERING THE DRUG ABUSE AS WELL AS TREATMENT PROCESSES. IN THE PRESENT WORK A NEWLY SYNTHESIZED IONIC LIQUID ABBREVIATED AS (ET)2EMIMNTF2, IS USED AS COATING OF A STAINLESS STEEL WIRE (METAL FIBRE) FOR EXTRACTION/PRECONCENTRATION OF METHADONE PRIOR TO ITS ANALYSIS BY GAS CHROMATOGRAPHY. THE INFLUENCE OF EXPERIMENTAL PARAMETERS SUCH AS INITIAL SAMPLE BASICITY, AGITATION RATE, TEMPERATURE, SALT CONCENTRATION, AND EQUILIBRIUM TIME ON THE EXTRACTION EFFICIENCY WAS STUDIED AND OPTIMIZED AS 3M NAOH, 700 RPM, 50OC, 30% (W/V) NACL, AND 30 MIN, RESPECTIVELY. UNDER OPTIMUM CONDITIONS, THE CALIBRATION GRAPH WAS LINEAR IN THE RANGE OF 10-50 AND 200-1000 NG ML-1. THE DETECTION LIMIT AND THE RELATIVE STANDARD DEVIATION WERE OBTAINED AS 1.29 NG ML-1 (3SB/M, N=6), AND 5.6% (N=6, C=500 NG ML-1), RESPECTIVELY. THE TECHNIQUE WAS SUCCESSFULLY APPLIED FOR BLOOD SAMPLE.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 170

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
نویسنده: 

KHAJEALI NASRIN | SARAJI MOHAMMAD

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    20
تعامل: 
  • بازدید: 

    159
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

CHLOROBENZENES ARE USED AS INDUSTRIAL SOLVENTS, PESTICIDES, DIELECTRIC FLUIDS, DEODORANT, AND CHEMICAL INTERMEDIATES. THEY CAN ENTER THE AQUATIC ENVIRONMENT THROUGH SOLID AND LIQUID EFFLUENTS AND ATMOSPHERIC DISCHARGES. BECAUSE THEY ARE RELATIVELY RESISTANT TO ABIOTIC AND BIOTIC DEGRADATION THEY TEND TO PERSIST IN THE ENVIRONMENT. CHLOROBENZENES ARE ESSENTIALLY UBIQUITOUS IN THE AQUATIC ENVIRONMENT, THEY CAN BE DETECTED IN WATER, SEDIMENT AND AQUATIC BIOTA [1].ELECTROSPINNING IS A SIMPLE, INEXPENSIVE TECHNIQUE THAT CREATESNANOFIBERS THROUGH AN ELECTRICALLY CHARGED JET OF POLYMER SOLUTIONOR MELT. THIS METHOD SHOULD PROVIDE ANAPPROACH TO GENERATE HIGH SURFACE AREA FIBERS AND THE VERSATILITYTO ALTER THE SPME FIBER COMPOSITION BY CHANGING THE POLYMERSOLUTION FOR ELECTROSPINNING [2, 3].IN THIS STUDY, SPME FIBERS WERE PRODUCED BY ELECTROSPINNING OF POLYACRYLONITRILE ON ALIMINIUM WIRES AND THEN THE NANOFIBERS WERE PYROLYZED TO GENERATE CARBON NANOFIBER SPME COATINGS. THE FIBER WAS THEN APPLIED FOR PRECONCENTRATIONAND DETERMINATION OF 1, 4-DICHLOROBENZENE (1, 4-DCB), 1, 2, 3-TRICHLOROBENZENE (1, 2, 3-TCB) AND 1, 2, 4-TRICHLOROBENZENE (1, 2, 4-TCB) IN WATER SAMPLES.VARIOUS FACTORS WHICH INFLUENCED THE RECOVERY OF THE ANALYTES WERE INVESTIGATED SUCH AS: FIBER THICKNESS, SALT ADDITION, EXTRACTION TIME, EXTRACTION TEMPERATURE, DESORPTIONTEMPERATURE AND TIME.DETECTION LIMITS WERE 10, 40, AND 400 NG/LFOR 1, 2, 4-TCB, 1, 2, 3-TCB, AND 1, 4-DCB, RESPECTIVELY.ALL RSDS WERE<9% (FORN=5). THE PROPOSED METHOD WAS APPLIED FOR THE ANALYSIS OF CHLOROBENZES IN SURFACE WATERS.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 159

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
litScript
telegram sharing button
whatsapp sharing button
linkedin sharing button
twitter sharing button
email sharing button
email sharing button
email sharing button
sharethis sharing button