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WELL-DESIGNED diesel engines in good repair, the author says, need not smoke while being operated on normal fuel if they are prevented from being overloaded. Unfortunately, he points out, with many types of current injection equipment, effective prevention of overloading over the entire speed range involves a reduction of the low-speed torque; in other words, sacrificing part of the lugging ability of the engine. The author makes the following suggestions to eliminate smoke: 1. For correcting a normally smoky exhaust, the smoke should first be diagnosed. 2. To eliminate hot smoke the mixing of the fuel and air should be improved. 3. To eliminate cold smoke ignition must be speeded up.

Particulate emissions of a two-stroke chainsaw engine were collected under controlled conditions in a test bench using a dilution tunnel for sampling. Two different types of gasolines and lubricating oils and the effect of exhaust after-treatment catalyst were studied. Particulate bound PAH:s and mutagenicity of the collected samples were determined. The particulates were found to originate mainly from the lubricating oil. There was a good correlation between the particulate bound PAH:s and the mutagenicity of the soluble organic fraction of the particulates. The amount of SOF was > 95% and originated mainly from lubricating oil. The catalyst performed more effectively with totally non-aromatic gasoline and synthetic lubricating oil than with reformulated gasoline with aromatics < 35 vol-% and mineral oil based lubricating oil.

The aim of this paper is to stimulate thought on how to accomplish the greatest possible economy in transportation over highways. The fundamental thought is that the expense of highway transportation involves a large number of items that can be grouped into those directly concerned with motor-truck operation and those involving the highway, and that highways and motor vehicles should be adapted mutually so that the greatest economy of transportation will result. Urging that the automotive and the road engineer cooperate in gathering information that will give them a more definite basis upon which to design the truck and the road, the present rapid destruction of roads is discussed and remedial measures suggested. The designing of motor trucks to conserve the roads is treated at some length and a plea for cooperation between the Society and the highway officials is made.

This paper describes the mathematical modeling of occupant kinematics in rollover accidents using the MVMA 2-D occupant motion simulation software. What little information is available on the kinematics of vehicle occupants during rollover accidents has been obtained either after the fact by accident reconstruction or by expensive experimentally-staged events. The paper describes the use of less expensive analytical techniques to graphically illustrate the applicability of occupant motion simulation computer models to this problem.

This paper describes further developments of the MVMA-2D model including program modifications of the air bag and the energy absorbing steering assembly submodels. The air bag submodel and the steering assembly submodel in the MVMA-2D crash victim simulation are independently formulated. No coupling exists between these two submodels to permit simulation of the kinematics of an anthropomorphic dummy restrained by a driver air bag restraint system mounted on a collapsible steering column. The development effort of integrating both submodels to provide the MVMA-2D model with such a capability is presented. The integrated model has been successfully utilized in simulating dynamic responses, in frontal impact situations, of a dummy restrained by a driver air bag restraint system mounted on a collapsible steering column. Validations of the model were made by comparing simulation results with experimental test data.

This paper describes a Heavy Truck Round Robin Brake Test involving three test vehicles at ten different proving grounds. The purpose of the program was to evaluate the practicality and repeatability of the test procedure proposed by the ABS Test Procedure Task Force of the Heavy Truck Subcommittee of the Motor Vehicle Safety Research Advisory Committee to NHTSA and to compare surface friction characteristics of dry high Mu and wet low Mu (coal tar emulsion sealed) test surfaces at different proving grounds.

Mass is one important suspicious object for breast cancer diagnosis in mammograms. Computer-aided detection (CAD) based on fully supervised deep learning achieves high performance for mass detection in mammograms. The lack of fine-grained expert labels becomes the bottleneck for the large-scale application of CAD to achieve detection in mammograms. Weakly supervised methods provide a solution to tackle the annotation problems, including in the application for mass detection. However, previous works face the problem of insufficient localization information, which affect the ability of mass detection. In this paper, we propose a multi-view enhancing mass detection network (MVMDNet) with dual view inputs that contains craniocaudal (CC) and mediolateral oblique (MLO) view of mammograms, where different view features are interacted and fused to enhance localization information.

Integration of Directed Energy Weapons (DEW) into future aircraft presents significant challenges. Principally, the need for generating and managing copious amounts of power into the Megawatt class is foreseen. Probably, the most critical and challenging area for supporting a DEW system on an aircraft is the Megawatt Class Electric Power System (MCEPS) and its associated Thermal Management Systems (TMS). MCEPS converts the aircraft fuel’s chemical energy into useable power for the load or system and the TMS disposes of the waste energy, all within the extremely challenging constraints (volume, weight, EMI, etc.) For the purposes of our studies, the MCEPS consists of the following subsystems: Engine, Power Generation, Power Conditioning, Distribution, Control, and Protection. The TMS manages Component Heat Extraction, Thermal Energy Storage, and Waste Heat disposal.

Motoren-Werke Mannheim AG (MWM) has designed a new series of V-type engines incorporating 6, 8, 12 and 16 cylinders. By means of careful component optimization for higher firing pressures, to be explained on the basis of a few examples, it was possible to increase the standard vehicle output by 63 % and the maximum output available for special vehicles by 100 % while maintaining the external dimensions of the previous series. Consequently, the values achieved for output per volume as well as weight per HP make these engines suitable for many different uses in vehicles up to 1088 HP and a few examples will also be given. The low fuel consumption over the whole operating range is of particular importance in this connection.

Motoren-Werke Mannheim AG has designed a new series of in-line 4 stroke cycle Diesel engines with 2, 3, 4 and 6 cylinders in naturally aspirated and, except the 2-cylinder engine, turbocharged version. Although the new design would have allowed to increase the displacement, the 105 mm bore and the 120 mm stroke as well as the external dimensions of the previous series were maintained. The explanation of the reasons for this decision is followed by a description how the increase of the performance range was achieved without enlarging the displacement. This involves mainly the load capacity of the engine components required by higher degrees of turbocharging and improved cooling. As installation in agricultural tractors is a main application the capability of the engine structure to be loaded by increased external torsional and bending moments was also an important requirement.

The importance of customer focus and integrating the customer into new product development is an objective we all embrace. Case Corporation h a s accomplished t h i s objective by defining a process for incorporating best practices in a systematic way combining methodology and tools in an organized program planning structure, which continuously involves the customer. This paper shows how the process will deliver a product that delights the customer.

THIS PAPER discusses the myths and fallacies regarding automation. According to the author, there is no such thing as an “automatic” factory, but merely degrees of automation. Advantages of automation are discussed in detail, especially in regard to productivity increases and labor displacement.

Mach-flow angularity probes were developed for use in scramjet flow path probe rakes. Prototype probes were fabricated to demonstrate the assembly processes (numerical control machining, furnace brazing, and electron beam welding). Tests of prototype probes confirmed the thermal durability margins and life cycle. Selected probes were calibrated in air at Mach numbers from 1.75 to 6.0. Acceptance criteria for the production probes stressed thermal durability and pressure (and, consequently, Mach number) measurement quality. This new water-cooled MFA probe has 0.397-cm shaft diameter and is capable of withstanding heat fluxes of 2.724 kW/cm2.

The alloy investigated in this research is Precipitation Hardened Stainless Steel (PHSS) 15-5, which provides good corrosion, high strength and hardness. 15-5 Stainless Steel is extensively employed in a variety of applications, including aero plane components, high-pressure corrosive environments that include valves, fasteners, shafts, fittings and gears. In this current exploration, an analysis of the machinability of PHSS is analyzed with textured inserts and the outcomes as compared to conventional inserts. To increase the machinability conditions, two distinct types of textures were produced on the rake face of the tool inserts and employed for this machining procedure utilizing a Wire Electric Discharge Machine (WEDM).The dimensions of the textures were cut on the trial-and-error method. Three different machining parameters with three different levels were chosen. Cutting Speed, feed rate and depth of cut were chosen as the input parameters.

An instrumented bench test has been developed to evaluate the machinability performance of P/M materials. The set-up consists of a high power press drill with automatic feed rate control coupled with a specially designed specimen holder which allows the monitoring of the torque applied on the cutting tool and the thrust transmitted to the test specimen. The feed rate and the rotating speed are also continuously recorded. All four variables, measured nine times per second, are transmitted to a data acquisition system and then to a computer for analysis. The changes in thrust force and torque during drilling are then related to tool wear which is evaluated by microscopic techniques. Two case studies are presented. In the first one, the machinability of forged FC-0205 specimens containing various types of MnS was compared; the high sensitivity of the bench test permitted to measure the effect of the various types of MnS powders on the machinability behavior of the materials.

THIS STUDY WAS DEVELOPED in response to a component fatigue strength test which determined that if the current #3 engine bearing cap were used in the 2.5L Turbo application, it would be over stressed. Proposed solutions for solving this problem included: a redesigned grey iron cap with additional material in the highly stressed areas, or a cap made from either nodular iron or a free machining steel using current specifications. One of the manufacturing concerns about switching materials is the perceived difference in the machinability of nodular iron and steel. A single point turning evaluation was carried out by Chrysler Motors' Machinability Development Laboratory to compare the machinability of various materials proposed for use in engine bearing caps. Materials tested included: SAE G2500 grey cast iron, the current production material; SAE D45-12 nodular cast iron; and SAE steel grades 1117, 1137, 1215, 12L14, 1215, and 1215 modified (Incut 200).

This modification process provides a method to a soft layer on surface of sintered material only where it is necessary for machining without deteriorating the material's strength properties. The soft layer is created on the objected surface through permeating aqueous solution of boric oxide to prevent the diffusion of graphite during sintering. Since the retained graphite is dispersed in the pore of soft ferrite matrix and gives a lubrication action during machining, it was confirmed that the machinability of developed material was greatly improved in compared to the material without the modification.

Titanium alloys are deemed as one amongst the light weight material most preferably adopted in numerous engineering applications due to its exceptional features such as corrosive resistance and thermal strength. These alloys are predominantly used in components of IC engines such as valves and springs, connecting rods. Especially Ti-Grade 5 adopted in aircraft, automobile parts ski plates and bicycles. The preliminary goal of this present research is to optimize the machining variables for Wire Electrical Discharge Machining (WEDM) of Ti-6Al-4V (Grade 5) to accomplish improved rate of material removal and surface finish. Taguchi’s design and analysis method was chosen for devising and examining the experiments by considering input factors (pulse duration and current). An L9 OA was utilized for experimentation to analyze the various output variables, such as surface finish and material removal rate, using the response analysis of Taguchi.