Low Cost Power and Supply Noise Estimation and Control in Scan Testing of VLSI Circuits

Test power is an important issue in deep submicron semiconductor testing. Too much power supply noise and too much power dissipation can result in excessive temperature rise, both leading to overkill during delay test. Scan-based test has been widely adopted as one of the most commonly used VLSI testing method. The test power during scan testing comprises shift power and capture power. The power consumed in the shift cycle dominates the total power dissipation. It is crucial for IC manufacturing companies to achieve near constant power consumption for a given timing window in order to keep the chip under test (CUT) at a near constant temperature, to make it easy to characterize the circuit behavior and prevent delay test over kill. To achieve constant test power, first, we built a fast and accurate power model, which can estimate the shift power without logic simulation of the circuit. We also proposed an efficient and low power X-bit Filling process, which could potentially reduce both the shift power and capture power. Then, we introduced an efficient test pattern reordering algorithm, which achieves near constant power between groups of patterns. The number of patterns in a group is determined by the thermal constant of the chip. Experimental results show that our proposed power model has very good correlation. Our proposed X-Fill process achieved both minimum shift power and capture power. The algorithm supports multiple scan chains and can achieve constant power within different regions of the chip. The greedy test pattern reordering algorithm can reduce the power variation from 29-126 percent to 8-10 percent or even lower if we reduce the power variance threshold. Excessive noise can significantly affect the timing performance of Deep Sub-Micron (DSM) designs and cause non-trivial additional delay. In delay test generation, test compaction and test fill techniques can produce excessive power supply noise. This can result in delay test overkill. Prior approaches to power supply noise aware delay test compaction are too costly due to many logic simulations, and are limited to static compaction. We proposed a realistic low cost delay test compaction flow that guardbands the delay using a sequence of estimation metrics to keep the circuit under test supply noise more like functional mode. This flow has been implemented in both static compaction and dynamic compaction. We analyzed the relationship between delay and voltage drop, and the relationship between effective weighted switching activity (WSA) and voltage drop. Based on these correlations, we introduce the low cost delay test pattern compaction framework considering power supply noise. Experimental results on ISCAS89 circuits show that our low cost framework is up to ten times faster than the prior high cost framework. Simulation results also verify that the low cost model can correctly guardband every path‟s extra noise-induced delay. We discussed the rules to set different constraints in the levelized framework. The veto process used in the compaction can be also applied to other constraints, such as power and temperature

Mechanism of Micro Manipulation using Oscillation

In this paper, we analyze the mechanism of the phenomenon between an endeffector, a micro object and a substrate during a micro manipulation. In a micro range, the attracting forces such as the van der Waals, capillary, and electrostatic forces dominate and course adhesion between the object and the endeffector. The adhesion makes the manipulation of an object difficult. Recently, we developed a method to reduce the attracting/adhesion effect. When bringing an oscillating endeffector close to a micro object on a substrate, the attracting force between the object and the endeffector is reduced, attracting the object to the substrate. Then, it becomes easy to remove the endeffector from the object. Using this method, a micro object can be easily manipulated. However, the mechanism of the phenomenon is still unclear. In this paper, we develop the theoretical model of the system to analyze the phenomenon, and simulate the dynamical motion of the system. Comparing the experimental results, we show the validity of our approach. Using simulation and experiment, we show that the oscillation of the endeffector can reduce the adhesion effect between the endeffector and the object, attracting the object to the substrate. © 2006 IEEE

Micromanipulation using squeeze effect

In this paper, we proposed a novel strategy for pick and place operation in a micro range, by using a squeeze effect In a micro range, the attracting forces such as the van der Waals, capillary, and electrostatic forces are dominate due to the scaling effect. The attracting forces make a release of an object difficult. In this paper, by vibrating the finger, we generate the gas film (the squeeze effect) between the object and the finger and relax the attracting forces. Some experimental results are shown to verify our approach

Mechanics of Hybrid Active/Passive-Closure Grasps

In this paper, we discuss the directions of active and passive force closures in hybrid active/passive-closure grasps. We show the directions are orthogonal to each other. We also discuss the magnitudes of the internal forces in the manipulation of the object. In hybrid active/passive-closure grasps, there exist two kinds of magnitudes of internal forces. One is the magnitude of internal forces, which changes if the object moves and the geometry of the fingers changes. The other is the one which don’t change even when the object moves. We derive these two magnitudes

Towards Whole Arm Manipulation by Contact State Transition

This paper discusses the whole arm manipulation allowing the contact state transition. For manipulation of an object under fully constrained, the contact state transition becomes necessary. In order to realize the object manipulation, we first derive the feasible direction of the object manipulation by analyzing the active/passive closure properties for every combination of contact states. Second, we derive the set of joint torque to move the object in the feasible direction. These analyses also provide the joint torque to realize the manipulation at the planned contact states. Effectiveness of the proposed method is confirmed by some simulation results. © 2006 IEEE

振動を用いた凝着力緩和とその微細操作への応用

金沢大学理工研究域機械工学系This paper addresses to develop a novel strategy to relax the adhesion forces for picking and placing operation in a micro range. In a micro range, the attracting forces such as the van der Waals, capillary, and electrostatic forces become dominating due to a scaling effect. The attractive forces cause the adhesion between the object and the endeffector. Therefore, it is hard to manipulate an object in a micro range. This paper shows that when an oscillating endeffector approaches to an object, the adhesion between the object and the oscillating endeffector can be reduced. Also, based on the experimental analysis, we clarify the relation between the oscillation and the pushing amount of the endeffector on the object, where the adhesion force can be released effectively. Using this relaxation method and the relation, we develop a strategy for picking and placing operation in a micro range. This strategy provides an accurate manipulation. Some experimental results show the effectiveness of this approach

Object Manipulation under Hybrid Active/Passive Closure

In this paper, we discuss the manipulation of an object under hybrid active/passive closure. We show the orthogonality between the directions of active and passive force closures for general grasping systems. Based on the orthogonality, we decompose the dynamics of grasping system into the "active part" and the "passive part". By using the decomposition, we show that the grasped object can be manipulated only by considering the dynamics of the active part. We also consider how to determine the desired internal forces in order to satisfy frictional constraints during the manipulation. In order to verify the validity of our approach, some simulation results are shown

Spontaneous weaving: 3D porous PtCu networks with ultrathin jagged nanowires for highly efficient oxygen reduction reaction

The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.apcatb.2018.04.035 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/We report a simple and efficient surfactant-free method to prepare 3D porous PtCu networks with ultrathin jagged nanowires and controllable composition. The morphological evolution and the influential effects of the important experimental parameters on the PtCu networks have been systematically studied. Relative to commercial Pt/C and Pt black catalysts, these porous PtCu networks exhibit much better activity and remarkably improved durability towards the oxygen reduction reaction (ORR). The excellent ORR performance could be attributed to their structural features, including the core-shell nanostructures with a Pt-skin, the 3D porous networks with high surface area, and the ultrathin (3.6 nm) jagged nanowires with plentiful edge/corner atoms. Notably, this method can be facilely extended to obtain PtCuAu trimetallic nanowire networks with high porosity, which exhibits its robustness for preparing novel 3D porous nanostructures with great potential in various catalytic applications.Natural Sciences and Engineering Research Council of Canada (NSERC) University of Waterloo, and the Waterloo Institute for Nanotechnology. NSERC, Catalysis Research for Polymer Electrolyte Fuel Cells (CaRPE FC) Network administered from Simon Fraser || Grant No. APCPJ 417858-1

Disseminated Acanthamoeba castellanii infection in a patient with AIDS: a case report and literature review

BackgroundAcanthamoeba castellanii infection is a rare condition primarily occurring in immunocompromised patients with extremely high mortality. Currently, there is no standard treatment for this condition, and successful treatment reports are scarce.Case presentationWe present a case of Acanthamoeba castellanii infection in a 63-year-old female patient with AIDS, who was admitted to our hospital with symptoms of fever, skin ulcers, subcutaneous nodules, and food regurgitation from the nose while eating. After initial empirical treatment failed, a biopsy of the subcutaneous nodule was performed, and metagenomic next-generation sequencing (mNGS) technology was used to detect pathogenic microorganisms in both the biopsy specimen and blood samples. The results revealed Acanthamoeba castellanii infection. Additionally, histopathological examination of the biopsy specimen and cytological examination of the secretions from the ulcer surface also confirmed this pathogenic infection. The patient’s symptoms significantly improved upon discharge after adjusting the treatment regimen to a combination of anti-amebic therapy.ConclusionImmunocompromised patients presenting with unexplained fever and skin or sinus lesions should be evaluated for Acanthamoeba castellanii infection. Multi-drug combination therapy is required for this organism infection, and a standard treatment protocol still needs further research. Metagenomic next-generation sequencing is a valuable tool for early diagnosis of unknown pathogen infections