Sears, Roebuck & Co. v. San Diego County District Council of Carpenters: Garmon Reconsidered and the Reaffirmation of Property Rights

Sears, Roebuck & Co. v. San Diego County District Council of Carpenters resolves the problem of a jurisdictional hiatus facing an employer when a union\u27s peaceful picketing on his property is within the ambit of the National Labor Relations Act (NLRA or the Act). Prior to the Sears decision, the right of the states to enjoin labor union picketing on an employer\u27s private property, when the union\u27s picketing was arguably protected and arguably prohibited, was uncertain. As a rule, conduct which is arguably protected under the Act or arguably prohibited under the Act, with few exceptions, cannot be the subject of litigation in state courts. However, on the sensitive issue of picketing on private property, state court decisions were in disarray with some courts ruling state trespass laws could be used against union members on private property and other courts ruling that state jurisdiction was preempted by the NLRA. Both the Warren Court and the Burger Court had left the issue open by consis- tently refusing to grant certiorari

The development of abrasive-corrosive wear resistance of steels by microstructural control

Bibliography: pages 212-223.The performance of developmental alloyed steels with improved abrasive-corrosive wear resistant properties has been evaluated. The synergistic effect of abrasion and corrosion in the accelerated wear of steels is examined and the main parameters identified. A model of the process is proposed. The model is used to develop the optimum abrasive-corrosive wear resistance in steels for applications in the gold mines of South Africa. A wide range of engineering steels, both commercially available and experimental, has been evaluated in laboratory simulated abrasive and abrasive-corrosive wear tests. An appraisal of the wear tests and the applicability of the results to in-service conditions has led to the development of an additional abrasive-corrosive wear test. It has been established that both the microstructure and chemical composition determine the resistance of a material to wear. Control of the microstructure by alloying and heat treatment is attempted in order to optimise the abrasive-corrosive wear resistant properties for each class of microstructure whilst maintaining adequate formability and weldability. Abrasion of a metal surface has been shown to accelerate the rate of corrosion. Three categories of corrosion behavior are defined. A model of the abrasive-corrosive wear process is proposed to account for the behavior. The model adequately predicts the outcome to a change in system parameter, namely: an increase in the corrosivity of the water, an increase in the frequency of abrasive events, a change in the chemical composition and the degree of passivity inherent in the material. Recommendations are made to maximize the abrasive-corrosive wear resistant properties without resorting to expensive highly alloyed steels. To satisfy the needs of the mining industry, two microstructures of note are identified: a metastable austenitic (TRIP type) steel and a 0.25% carbon lath martensitic alloyed steel. A basic chemical composition is proposed with each microstructure. The austenitic steel is shown to achieve its abrasion resistance through the high degree of work hardening it undergoes during abrasion and the high ultimate strength of the strained material. The lath martensitic steel has the necessary strength to toughness ratio for good abrasion resistance. A 20% degree of work hardening in conjunction with a bulk hardness in excess of 500 HV is prescribed for superior abrasion resistant properties in the wear system of the mines. The life time cost of the martensitic alloyed steel recommends it for applications in the gold mines of South Africa

Design of ternary signals for MIMO identification in the presence of noise and nonlinear distortion

A new approach to designing sets of ternary periodic signals with different periods for multi-input multi-output system identification is described. The signals are pseudo-random signals with uniform nonzero harmonics, generated from Galois field GF(q), where q is a prime or a power of a prime. The signals are designed to be uncorrelated, so that effects of different inputs can be easily decoupled. However, correlated harmonics can be included if necessary, for applications in the identification of ill-conditioned processes. A design table is given for q les 31. An example is presented for the design of five uncorrelated signals with a common period N = 168 . Three of these signals are applied to identify the transfer function matrix as well as the singular values of a simulated distillation column. Results obtained are compared with those achieved using two alternative methods

Stability and Relative Stability of Linear Systems with Many Constant Time Delays

A method of determining the stability of linear systems with many constant time delays is developed. This technique, an extension of the tau-decomposition method, is used to examine not only the stability but also the relative stability of retarded systems with many delays and a class of neutral equations with one delay. Analytical equations are derived for partitioning the delay space of a retarded system with two time delays. The stability of the system in each of the regions defined by the partitioning curves in the parameter plane is determined using the extended tau-decomposition method. In addition, relative stability boundaries are defined using the extended tau-decompositon method in association with parameter plane techniques. Several applications of the extended tau-decomposition method are presented and compared with stability results obtained from other analyses. In all cases the results obtained using the method outlined herein coincide with and extend those of previous investigations. The extended tau-decomposition method applied to systems with time delays requires less computational effort and yields more complete stability analyses than previous techniques

The analytical determination of friction for flow through conical converging dies

The effects of friction upon the intermediate and final distorted grids for wire drawing and/or extrusion were analytically studied for an assumed triangular velocity field. An upper-bound solution process was used. This solution predicted that the shape of the final and intermediate distorted grids were functions of the process geometry of friction

advligorts: The Advanced LIGO Real-Time Digital Control and Data Acquisition System

The Advanced LIGO detectors are sophisticated opto-mechanical devices. At the core of their operation is feedback control. The Advanced LIGO project developed a custom digital control and data acquisition system to handle the unique needs of this new breed of astronomical detector. The advligorts is the software component of this system. This highly modular and extensible system has enabled the unprecedented performance of the LIGO instruments, and has been a vital component in the direct detection of gravitational waves

A Kinematically Intelligent Blackboard for Computer Aided Instruction

A CAI (computer-aided instruction) package is being developed to be used as a classroom tool for the instruction of undergraduate mechanical engineering students in an introductory kinematics of mechanisms course. This graphical environment allows the instructor to emulate on the projected graphics screen everything that is currently done on the blackboard for planar mechansims. Unlike the blackboard, the software will have the intelligence to interpret the drawings in a kinematic sense so that the drawing of the linkage will behave as a linkage. The software environment involves three principal components: (1) a sketching method for defining the linkage, (2) the kinematic intelligence to interpret the sketch and animate the linkage, and (3) the ability to develop and demonstrate kinematic concept

Space-based Communications Infrastructure for Developing Countries

This study examines the potential use of satellites to augment the telecommunications infrastructure of developing countries with advanced satellites. The study investigated the potential market for using satellites in developing countries, the role of satellites in national information infractructures (NII), the technical feasibility of augmenting NIIs with satellites, and a nation's financial conditions necessary for procuring satellite systems. In addition, the study examined several technical areas including onboard processing, intersatellite links, frequency of operation, multibeam and active antennas, and advanced satellite technologies. The marketing portion of this study focused on three case studies: China, Brazil, and Mexico. These cases represent countries in various stages of telecommunication infrastructure development. The study concludes by defining the needs of developing countries for satellites, and recommends steps that both industry and NASA can take to improve the competitiveness of U.S. satellite manufacturing

Resilient energy harvesting systems

PhD ThesisDeveloping resilient sensor systems for deployment in extreme environments is a challenge which silicon carbide, along with other wide band gap materials, stands to play a major role in. However, any system developed will be hindered in its usefulness unless the problem of providing a power supply in these extreme conditions is addressed. This work addresses this need; a wireless sensor node conceived of standard o the shelf components was first developed and used as the basis for the design considerations required for a silicon carbide sensor node. The silicon system developed uses a piezoelectric energy harvester for the power supply and exhibits favourable operating characteristics for low vibration environments. It is capable of continuous operation at 120 mg (1.177 ms2) and at 40 mg operates with a system duty cycle of 0.05. PZT, a standard piezoelectric energy harvesting material, was characterised to 300 C to test its resilience to the conditions found in hostile environments. The material degrades considerably with temperature, with a decrease in Youngs modulus from 66 GPa at room temperature to 8.16 GPa at 300 C. The room temperature value is repeatable once cooled with an observed hysteresis in the upper temperature range. The peak output voltage at resonance also varies with temperature, resulting in an 11.6% decrease in room temperature voltage once the device is heated to 300 C. The output voltage at 300 C is found to be 2.05 V, a considerable decrease from the initial 11.1 V output at room temperature. The decrease in voltage with temperature is not monotonic as maybe expected, the data showing that at 473 K there is an increase in output voltage which is caused by a decrease in mechanical damping. SiC pin diodes were fabricated with wide drift regions to promote a large depletion width, in order to maximise the capture cross section of incident light on the devices. The large drift region produces a high series resistance. However, ll factors above 0.7 show that the device is not signi cantly a ected. SiC is shown to be an e ective UV harvester with an observed increase in output power from 0.17 mWcm2 at room temperature to 0.32 mWcm2 at 600 i K. Fill factor also remains stable with temperature, indicating that the device is not a ected by variation in parameters such as shunt and series resistances or the ideality factor. There are current technological di culties which preclude the manufacture of large area silicon carbide solar cells and as such, an alternative networking solution is presented as a way to increase the output power of the devices. Given that these devices would be subject to long term high temperature exposure, a 700 hour thermal stress test is carried out at 450 C to explore the failure mechanism of the devices. There is an observed decrease in device ll factor which indicates that the device su ers increasing degradation. The data shows that this is caused by increasing series resistance, which reduces the devices ability to output power. SEM imaging and SIMS analysis show this is likely caused by signifcant metal diusion in the contact stack which could potentially be overcome by the addition ofan alternative di usion barrier. Once energy is generated by an energy harvester is must be stored so that it can be used when required. To this end both substrate and on chip storage technologies are discussed in the forms of AlN and HfO2 metal insulator metal (MIM) capacitors. To test the feasibility of both solutions, AlN and HfO2 MIM capacitors were characterised to 300 C. The HfO2 device leakage has a strong temperature dependence as observed in the IV characteristics and the capacitance density does not scale according to parallel plate theory. However, the devices can be e ectively networked and their leakage reduced with series connection. The internal voltage decay of the device is reduced with series connection, due to the di er-ing work functions of the metal-insulator contacts. The alternative AlN solution exhibits substantially weaker temperature dependance and signi cantly improved lm quality. The data shows no existence of a barrier at the insulator - metal interface, as observed in the HfO2 device IV characteristics. The extracted activation energy is stable with temperature at 1.26 +/- 0.15 eV indicating a trap assisted leakage mechanism. This method is more suitable to fabrication of large area storage as it can be fabricated o chip on a less expensive substrate and the devices fabricated exhibit a higher yield than the HfO2 devices

Mitochondrial genomes and thousands of ultraconserved elements resolve the taxonomy and historical biogeography of the Euphonia and Chlorophonia finches (Passeriformes: Fringillidae)

© 2020 American Ornithological Society. Relationships of the Neotropical finches in the genera Euphonia and Chlorophonia (Fringillidae: Euphoniinae) have been clarified by recent molecular studies, but species-level relationships within this group have not been thoroughly addressed. In this study, we sampled specimens representing every recognized species of these genera, in addition to 2 outgroup taxa, and used target enrichment to sequence thousands of ultraconserved element (UCE) loci, as well as mitochondrial DNA reconstructed from off-target reads, from each specimen to infer these relationships. We constructed both concatenation and coalescent-based estimates of phylogeny from this dataset using matrices of varying levels of completeness, and we generated a time-scaled ultrametric tree using a recently published fossil-based external calibration. We found uniformly strong support for a monophyletic subfamily Euphoniinae and genus Chlorophonia, but a paraphyletic Euphonia across UCEs and mitochondrial genomes. Otherwise, our inferred relationships were largely concordant with previous studies. Our time-tree indicated a stem divergence time of 13.8 million years ago for this lineage, followed by a relatively young crown age of only 7.1 myr. Reconstructions of biogeographic history based on this tree suggest a South American origin for crown Euphoniinae, possibly resulting from a transoceanic dispersal event from the Eastern Hemisphere, followed by 2 dispersal events into the Caribbean and as many as 6 invasions of North America coinciding with recent estimates of the age at which the Isthmus of Panama had completely formed. We recommend splitting Euphonia and resurrecting the genus Cyanophonia for the 3 blue-hooded species more closely related to Chlorophonia. Based on our results, we suspect that there is undescribed species-level diversity in at least one, possibly many, widespread and phenotypically diverse species