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The effect of vehicle acceleration history on dummy loading in the frontal impact NCAP event is explored with help of a one-dimensional mathematical model. Both numerical and analytical approaches are used to identify the ideal vehicle pulse. The numerical solution reveals limitations of square wave pulse. The analytical approach results in explicit formulation of the ideal pulse. Response of the mathematical model used in this paper is statistically correlated to a number of randomly selected NCAP frontal tests. Both the baseline model and the resulting optimized pulse are also confirmed using a validated three-dimensional Madymo model. Based on the analytical results, a simple measure of quality of the vehicle acceleration history is formulated.

Yield potential was predicted and mapped for three corn fields in Central Illinois, using digital aerial color infrared images. Three methods, namely statistical (regression) modeling, genetic algorithm optimization and artificial neural networks, were used for developing yield models. Two image resolutions of 3 and 6 m/pixel were used for modeling. All the models were trained using July 31 image and tested using images from July 2 and August 31, all from 1998. Among the three models, artificial neural networks gave best performance, with a prediction error less than 30%. The statistical model resulted in prediction errors in the range of 23 to 54%. The lower resolution images resulted in better prediction accuracy compared to resolutions higher than or equal to the yield resolution. Images after pollination resulted in better accuracy compared to images before pollination.

Instantaneous combine grain yield monitors need to provide reliable yield measurements since yield as a function of location is key information needed to manage fields by management zones. A scale and a yield monitor measured the same stream of grain and provided similar results when compared to each other. Data from either device may be misinterpreted if care in calibration and operation is not taken. Careful operators who pay attention to calibration, maintenance, and manufacturer's instructions will be required.

Growth Temperatures And Lighting Intensity Are Key Factors That Directly Impact The Design, Engineering, And Horticultural Practices Of Sustainable Life-Support Systems For Future Long-Term Space Missions. The Effects Of Exposure Of Lettuce (Cv. Flandria), Radish (Cv. Cherry Bomb Ii). And Green Onion (Cv. Kinka) Plants To Controlled Environment Temperatures (Constant Day/Night Temperature Of 22, 25, Or 28 °C) And Lighting Intensities (8.6, 17.2, Or 25.8 Mol M−2 D−1 Photosynthetic Photon Flux [Ppf]) At Elevated Co2 (1200 µMol Mol−1) Was Investigated To Ascertain Overall Yield Responses. Following 35 Days Growth, The Yields Of Lettuce Indicated That Increasing The Growing Temperature From 22 To 28°C Slightly Increased The Edible Fresh Mass Of Individual Plants. However, Even Though Lettuce Plants Grown Under High Ppf Had The Highest Fresh Mass, The Resultant Increase In The Incidence And Severity Of Tipburn Reduced The Overall Quality Of The Lettuce Head.

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Development of car production industry in Yugoslavia has three ecological phases. The first one is to satisfy ECE Rules by optimization of engine and vehicle equipment. The second phase is to enter the American market with help of professional foreign development institutions. The third phase is now in focus; to adjust to new European regulations. For the development tasks it is typical to lean on foreign licenses. The real development jobs were occasionally given to faculties, while the research units in factories were overburdened by operative tasks from production. Research jobs were always at mother companies, only some small segment of them was, for the short period, at some faculty or larger institute.

This specification covers a zinc alloy in the form of die castings.

This paper describes the development of a set of algorithms that find the takeoff gross weight of an aircraft for given vehicle and engine characteristics, and mission requirements. A major objective was to find the most elementary set that would still yield useful answers. The result was a set that could be encoded on an inexpensive programmable pocket calculator with only 24 lines of code. Results are compared with actual characteristics of an executive jet and its derivative versions.

Conventional attribute sampling plans based upon nonzero acceptance numbers are no longer desirable. In addition, emphasis is now placed on the quality level that is received by the customer. This relates directly to the Lot Tolerance Percent Defective (LTPD) value or the Limiting Quality Protection of MIL-STD-105. Measuring quality levels in percent nonconforming, although not incorrect, has been replaced with quality levels measured in parts per million (PPM). As a result, this standard addresses the need for sampling plans that can augment MIL-STD-105, are based upon a zero acceptance number, and address quality (nonconformance) levels in the parts per million range. This document does not address minor nonconformances, which are defined as nonconformances that are not likely to reduce materially the usability of the unit of product for its intended purpose.

(From Standards Proposal No. 2358, formulated under the cognizance of the EIA Quality and Reliability Engineering (QRE) Committee.)

Increasingly stringent emission levels require better quality facility gas supplies to enable more precise measurements at low levels and reduce variation in test results. The transient and steady state quality of the “zero gas” used in analyzer calibration will directly affect the level of the readings, while variation in the “zero gas” over time will increase the number of tests needed to meet statistical requirements. Facility zero gas supplies for air and nitrogen, at a minimum, require careful evaluation to confirm that the required gas quality is delivered to the test equipment for the desired instrument accuracy. To move from LEV or ULEV to SULEV analysis, a change in methodology of zero gas generation, delivery and handling may be needed to achieve the desired measurement accuracy and repeatability. Traditional tubing, fittings and handling methods can not only limit the possible gas quality, but also contribute to variation.

As the demand for more complex system development and the ever-increasing requirement for improvement in software productivity, the need for graphical programming or Zero-Hand Coding for automatic generation of controller software becomes highly desirable. The graphical programming must not be limited to the algorithm development which consists of the application modules but must be extended to the microcontroller platform, which include the middleware (i.e. operating system, I/O device drivers) and hardware. Automatic code generation is very important for programming the complex microcontroller internal parameters and registers. The combined software tool chain is to generate the final target specific executable code. This approach is very beneficial for system development, reduction of the development cycle and bridges the gap between control and software engineers reducing time, effort and cost of the production software.

In the developement process, the engineer is required to design, validate and deliver the components for manufacturing, in an as short as possible lead time. For that, the engineer may use some available tools to save not only time, but also cost. This work presents a zero prototype approach applyied to a plastic component, whose main accomplishment was the decreasing of lead time development due to the intensive use of virtual tools (CAD/CAE). As a result, the product was delivered in a short time, with no need of building physical prototypes, thus reducing development cost.

Delphi's Zero Resistance Technology (ZRT) is a revolutionary new product/process that enables the reduction of mass and volume from a traditional wiring assembly. ZRT is defined as a minimal (zero) resistance change over time. The ZRT product is an electrical/electronic connection system which provides a viable solution for high density and limited space wiring applications. The ZRT process is a semi-automated wiring harness manufacturing system with flexibility to produce harnesses to the customer demand.

Zero-dimensional heat release rate models have the advantage of being both easy to handle and computationally efficient. In addition, they are capable of predicting the effects of important engine parameters on the combustion process. In this study, a zero-dimensional combustion model based on physical and chemical sub-models for local processes like injection, spray formation, ignition and combustion is presented. In terms of injection simulation, the presented model accounts for a phenomenological nozzle flow model considering the nozzle passage inlet configuration and an approach for modeling the characteristics of the Diesel spray and consequently the mixing process. A formulation for modeling the effects of intake swirl flow pattern, squish flow and injection characteristics on the in-cylinder turbulent kinetic energy is presented and compared with the CFD simulation results.

A zero-dimension model of spray development and particulate emissions for direct-injection combustion was developed. The model describes the major characteristics of the injection plume including: spray angle, liquid penetration, lift-off length, and temperatures of regions within the spray. The model also predicts particulate mass output over a span of combustion cycles, as well as a particulate mass-history over a single combustion event. The model was developed by applying established conceptual models for direct injection combustion to numerical relations, to develop a mathematical description of events. The model was developed in a Matlab Simulink environment to promote modularity and ease of use.

Internal combustion engines development with increased complexity due to CO2 reduction and emissions regulation, while reducing costs and duration of development projects, makes numerical simulation essential. 1D engine simulation software response for the gas exchange process is sufficiently accurate and quick. However, combustion simulation by Wiebe function is poorly predictive. The objective of this paper is to compare different approaches for 0D Spark Ignition (SI) modeling. Versions of Eddy Burn Up, Fractal and Flame Surface Density (FSD) models have been coded into GT-POWER platform, which connects thermodynamics, gas exchange and combustion sub-models. An initial flame kernel is imposed and then, the flame front propagates spherically in the combustion chamber. Flame surface is tabulated as a function of piston position and flame radius. The modeling of key features of SI combustion such as laminar flame speed and thickness and turbulence was common.

For human beings who have been reared on the earth with its 1 G gravitational field, the condition of weightlessness is a world with which we are unfamiliar. Even if the layout and equipment configuration of a spacecraft designed to compensate for operation under Zero-G conditions, there are some things which are not effective under actual weightless conditions. In the design of a manned spacecraft, it is necessary to accumulate design data on human performance in a weightless condition, then to undertake design evaluations and verification under weightless conditions. In this paper, testing for the purpose of evaluating the effectiveness of Zero-G simulation using neutral buoyancy, conducted first of all in Japan, and recommendations on the equipment and Facilities required to conduct such simulations, are described.

A zero-dimensional dynamic model was developed in the Matlab/Simulink® environment to predict the behaviour of a variable-displacement lubricating vane pump for internal combustion engine applications. Based on the geometric and kinematic characteristics of the pump, the model allows predictions of the pressure evolution in each chamber of the pump and in the delivery piping, by employing an integrative-derivative approach. Simulation results were compared with experimental data of pressure transducers, which were fitted along the periphery of the pump case and in the delivery channel. The analysis of the experimental data shows that the pressure dynamics, which is experienced by the transducers, is in some cases quite different from the pressure dynamics in the pump chambers and produces pressure peaks which are not actually present in the original signal. The pressure transducers output was then also modelled in order to properly compare simulation results and experimental data.