This paper identifies requirements for an engineering design information management system. Future CAD systems must support a wide range of activities — such as definition, manipulation and analyses of complex product information models. These models represent not only conventional data associated with current CAD applications, but also design information characterizing the correlations between the requirements, functions, behaviors and physical form of the product. Such functionality is important for both the individual designer and the design organization, as the need to manage information as a corporate asset is becoming a critical component of business strategy. This paper explores these needs using two design studies. The first study illustrates some major concepts relative to non-routine design activities, while the second study focuses on the routine design activities relative to organization interactions. These studies were used to elicit high level requirements which serve as the basis for the development of prototype software systems. These prototypes are briefly introduced here. 相似文献
An algorithm for sharpening blurred as well as noisy image is proposed. The working formula has been derived incorporating characteristics of human visual system. The new algorithm is implemented on a set of image and the performance of the present technique is compared with those of other conventional spatial domain techniques. 相似文献
Explores bioinformatics-based modeling of immunological instabilities. We develop an algorithm for analyzing stability-instability properties of complex systems and use the developed technique to induce transitions in physical, biological and engineering systems. As a case study, we analyze the phenomena of tumor destabilization or spontaneous biological regression of a malignant focus-lymphocyte interactive system. Using stochastic noise analysis, we model high-dimensional collective oscillations of nonlinear elements and study nonautonomous systems with oscillation-induced phase transitions between lowand high-dimensional states. The associated nonlinear immunodynamical phenomenon of nonequilibrial destabilization of a malignant tumor is analyzed in terms of the Prigogine-Glansdorff (1971) stability theorem of dynamical systems theory 相似文献
We report on steady-state measurements on the anisotropy of autofluorescence from malignant and normal breast tissue as a function of tissue thickness. For thin tissue sections the anisotropy from normal tissue was found to be smaller compared with that from malignant tissue. However, the opposite result was obtained for thicker tissues. A phenomenological model was also developed to simulate the dependence of anisotropy on tissue thickness. 相似文献
With the advent of semiconductor process technology, both the dynamic and static power consumption have become major concerns for the circuit designers. Though clock gating (CG) is a potentially accomplished technique to minimise the dynamic power, it generally fails to cut down the static power dissipation. To address the same, we have unveiled a new CG scheme incorporating leakage control transistor, which simultaneously curbs the static and dynamic power along with the alleviation of power supply noise (PSN) in silicon chips by smartly controlling the current ramp (di/dt) and average current i(t): the main contributors to PSN. The proposed CG does not only save average, dynamic and static power by 84.34%, 90.33% and 66.73%, respectively, but also reduces PSN by 84.44% with respect to its non-gated counterpart when simulated using Cadence Virtuoso® for 90 nm Generic Process Design Kit at a switching frequency of 5 GHz and power supply voltage of 1.1 V. 相似文献
Diospyrin is a plant product that has significant inhibitory effect on the growth of Leishmania donovani promastigotes. This compound inhibits the catalytic activity of DNA topoisomerase I of the parasite. Like camptothecin, it induces topoisomerase I mediated DNA cleavage in vitro. Treatment of DNA with diospyrin before addition of topoisomerase I has no effect. Preincubation of topoisomerase I with diospyrin before the addition of DNA in the relaxation reaction increases this inhibition. Our results suggest that this bis-naphthoquinone compound exerts its inhibitory effect by binding with the enzyme and stabilizing the topoisomerase I-DNA "cleavable complex." Diospyrin is a specific inhibitor of the parasitic topoisomerase I. It does not inhibit type II topoisomerase of L. donovani and requires much higher concentrations to inhibit type I topoisomerase of calf thymus. The potent inhibitory effect of diospyrin on type I DNA topoisomerase from L. donovani can be exploited for rational drug design in human leishmaniasis. 相似文献
The signal integrity metrics such as jitter, noise, peak-to-peak signal swing and power dissipation play a pivotal role in determining the quality of high data rate on-chip wireline communication and a decision circuit is the most vital section of it. This article explores an area efficient 40 Gb/s configuration of passive element free current mode decision module implemented in 90 nm CMOS technology. The simulation using Cadence Virtuoso platform is carried out at a power supply of 1.2 V along with a clock frequency of 40 GHz and pseudo random bit sequence data input of (27 − 1) having 1 ns bit period. The device foot print of entire arrangement is (76 × 23) µm2, which reads a power dissipation, delay, PDP, peak-to-peak jitter and RMS jitter of 7.02 mW, 198.1 ps, 1.391 pJ, 58.00 ps and 13.12 ps respectively. Monte Carlo runs with ‘no skew’ and 5% process skew are performed at different corners to prove the robustness of the design. The whole circuit is finally validated at lower technology node like 28 nm UMC.
This article proposes a design approach of common source (CS) amplifier based Voltage Controlled Oscillator (VCO) to derive higher oscillation frequency. The working feature is such that, the active load of CS amplifier is varied to modulate the flow of current based on a bias circuit steered by an external controlled voltage (Vctrl), which controls the delay of each stage and thereby regulates the oscillation frequency. The circuit is designed and analyzed on Cadence Virtuoso platform at a supply voltage of 1.2 V for 90 nm CMOS to read a device footprint of 0.105 mm2, which offers a power burn and frequency of 2.092 mW and 9.21 GHz respectively with a phase noise and output noise of − 137.9 dBc/Hz and − 168.40 dB at 1 MHz offset frequency. To justify the reliability of the circuit we have conducted worst case analysis by considering effect of power delivery network (PDN) and corner variation along with 500 runs of Monte Carlo. The design is also introduced under 28 nm UMC to validate its scalability with technology trends.