49 research outputs found
Tunable Versatile High Input Impedance Voltage-Mode Universal Biquadratic Filter Based on DDCCs
A high input impedance voltage-mode universal biquadratic filter with three input terminals and seven output terminals is presented. The proposed circuit uses three differential difference current conveyors (DDCCs), four resistors and two grounded capacitors. The proposed circuit can realize all the standard filter functions, namely, lowpass, bandpass, highpass, notch and allpass, simultaneously. The proposed circuit offers the features of high input impedance, using only grounded capacitors, and orthogonal controllability of resonance angular frequency and quality factor
Current-Mode Third-Order Quadrature Oscillator Using CDTAs
This paper describes a current-mode third-order quadrature oscillator based on current differencing transconductance amplifiers (CDTAs). Outputs of two current-mode sinusoids with 90° phase difference are available in the quadrature oscillator circuit. The oscillation condition and oscillation frequency are orthogonal controllable. The proposed circuit employs only grounded capacitors and is ideal for integration. Simulation results are included to confirm the theoretical analysis
Voltage-Mode Universal Biquadratic Filter Using Two OTAs
A four-inputs and two-outputs voltage-mode universal biquadratic filter using only two operational transconductance amplifiers (OTAs) and two capacitors is presented. The new circuits offer several advantages, such as employing the minimum number of active and passive components (two OTAs and two capacitors); the versatility to
synthesize highpass, bandpass, lowpass, notch and allpass responses; high input impedance and employing only grounded capacitors for bandpass and lowpass filter realizations; some derived filter types enjoy the availability of one more simultaneously output filter response and good sensitivities performanc
Multicriteria Resource Brokering in Cloud Computing for Streaming Service
By leveraging cloud computing such as Infrastructure as a Service (IaaS), the outsourcing of computing resources used to support operations, including servers, storage, and networking components, is quite beneficial for various providers of Internet application. With this increasing trend, resource allocation that both assures QoS via Service Level Agreement (SLA) and avoids overprovisioning in order to reduce cost becomes a crucial priority and challenge in the design and operation of complex service-based platforms such as streaming service. On the other hand, providers of IaaS also concern their profit performance and energy consumption while offering these virtualized resources. In this paper, considering both service-oriented and infrastructure-oriented criteria, we regard this resource allocation problem as Multicriteria Decision Making problem and propose an effective trade-off approach based on goal programming model. To validate its effectiveness, a cloud architecture for streaming application is addressed and extensive analysis is performed for related criteria. The results of numerical simulations show that the proposed approach strikes a balance between these conflicting criteria commendably and achieves high cost efficiency
Associations between Arsenic in Drinking Water and Pterygium in Southwestern Taiwan
[[abstract]]BACKGROUND: Pterygium is a fibrovascular growth of the bulbar conjunctiva and underlying subconjunctival tissue that may cause blindness. The mechanism of pterygium formation is not yet fully understood, but pterygium has some tumorlike features. OBJECTIVES: The objective of this study was to evaluate the association between arsenic exposure through drinking water and the occurrence of pterygium in southwestern Taiwan. METHODS: We recruited participants > 40 years of age from three villages in the arseniasis-endemic area in southwestern Taiwan (exposure villages) and four neighboring nonendemic villages (comparison villages). Each participant received an eye examination and a questionnaire interview. Photographs taken of both eyes were later graded by an ophthalmologist to determine pterygium status. RESULTS: We included 223 participants from the exposure villages and 160 from the comparison villages. The prevalence of pterygium was higher in the exposure villages across an age groups in both sexes and increased with cumulative arsenic exposure. We found a significant association between cumulative arsenic exposure and the prevalence of pterygium. After adjusting for age, sex, working under sunlight, and working in sandy environments, we found that cumulative arsenic exposure of 0.1-15.0 mg/L-year and >= 15.1 mg/L-year were associated with increased risks of developing pterygium. The adjusted odds ratios were 2.04 [95% confidence interval (CI), 1.04-3.99] and 2.88 (95% CI, 1.42-5.83), respectively. CONCLUSIONS: Chronic exposure to arsenic in drinking water was related to the occurrence of pterygium, and the association was still observed after adjusting for exposures to sunlight and sandy environments
Current-mode and transimpedance-mode universal biquadratic filter using multiple outputs CCIIs
169-174A current-mode and transimpedance-mode universal biquadratic
filter with single input and multi-outputs using three multiple outputs
second-generation current conveyors (MOCCIIs), five resistors and two grounded
capacitors is presented. The proposed circuit can realize current-mode notch, bandpass
and lowpass responses, simultaneously. The current-mode highpass and allpass
responses can be obtained by interconnection of relevant output currents. Moreover,
the transimpedance-mode highpass, bandpass, lowpass, notch and allpass filters
can also be obtained, simultaneously, from the proposed circuit
Current-mode universal biquadratic filter with five inputs and one output using three ICCIIs
214-217A current-mode
universal biquadratic filter with five inputs and one output employing three
inverting second-generation current conveyors (ICCIIs), two grounded capacitors
and two resistors is presented. The new circuit offers the following advantage
features: very low active and passive sensitivities, using of grounded
capacitors that is ideal for integrated circuit implementation, the versatility
to synthesize any type of active filter transfer functions without requirements
for critical component matching conditions, very high output impedance and needs not another current
follower to duplicate the input current signal for the realization of notch or
allpass responses.</b
Voltage/current-mode universal biquadratic filter using single CCII+
749-756Voltage/current-mode universal biquadratic filter using single plus-type
second-generation current conveyor (CCII), two capacitors and two resistors has
been presented. The proposed voltage-mode circuit has
three inputs and two outputs and can realize all the standard filter functions,
which are, lowpass, bandpass,
highpass, notch and allpass filters, without changing the circuit topology. One
more simultaneous output filter response can be obtained from some derived
filter types. The proposed current-mode circuit has two inputs and three
outputs and can realize all the standard filter functions without changing the
circuit topology. Each of the proposed circuits employs only one plus-type CCII
(CCII+) that simplifies the configuration