Elif TEMİZ, 030070195, 3rd Week Definitions

1-FLame Hardening (Previous)
Flame hardening involves direct inplegement of oxyfuel gas from suitably designed and positioned burners onto the surface area to be hardened followed by quenching.The result is a hard surface layer of martensite over a softer interior core.There is no change in composition and therefore the flame hardened steel must have adequatecarbon content for the desired surface hardness.The rate of heating and the conduction of heat into the interior appear to be more important inestablishing case depth than the use of a steel of high hardenability.

(Surface hardening of a steels,Asm international, p.237)

FLAME HARDENING (New)(Better) (Surface Treatment Method)         

Flame Hardening involves heating the work surface by means of one or more torches followed by rapid quenching. As a hardening process, it is applied to carbon and alloy steels, tool steels and cast irons. Fuels include acetylene (C₂H₂), propane (C₃H₈), and other gases. The name flame hardening invokes images of a highly manual peration with general lack of control over the results; however, the process can be set up to include temperature control, fixtures for positioning the work relative to the flame, and indexing devices that operate on a precise cycle time, all of which provide close control over the resulting heat treatment. It is fast and versatile, lending itself to high production as well as big components such as large gears that exceed the capacity of furnaces.

(Groover, M. P. Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, p.665)

2-Phase Change Materials (Previous)

Phase-change materials are compounds coated onto carrier materials or substrates, both electrically

 insulating and conductive, and then placed between the heat-producing part and the heat sink or

circuit card assembly. The materials are placed under pressure and subsequently heated externally

 or self-heated to the material's melting temperature, where it softens and fills all of the interstitial voids

 between the parts and the heat sink.

(Charles A. Harper, Electronic Packaging and Interconnection Handbook,Fourth edition, pg 344,345)

Phase Change Materials(New) (Better) (Material)

Phase Change Materials (PCMs) are a class of compounds that exhibit a metastability in their crystal structure that facilities a structural change, from crystalline to amorphous and vice versa, upon some external stimulus. Of course, with the right excitation one can always change a material’s phase, say from liquid to solid and back. Here, what is meant by a “phase” change is a small rearrangement of the atomic structure; these materials posses two states in configuration space that are similar in energy. The energy barrier appears to be on the order of an eV, since switching between states is usually accomplished by application of a pulse of visible light or an equivalent electrical current. Concurrent with structural changes are rather dramatic changes in the optical and electrical properties. For instance, some compounds become = 10³ more resistive in the amorphous phase when compared to the crystalline phase. The optical constast is less pronounced, but still provides an adequate dynamic range for technological applications. For instance, the 20-30% difference in reflectively of red light is sufficient to reliably distinguish between the amorphous and crystalline states.

Recently, materials with the composition Ge_xSb_yTe_1=x=y, where 0<= (x,y) <= 1, and most notably Ge₂Sb₂Te₃ have surfaced as the industry paradigm for device application. These compounds exhibit the most favorable industry metrics (e.g., switching speeds, cycle-life, and scaling characteristics) for use in optical storage media and re-programmable memory devices. Thus the motivation for studying these materials is clear from the industry perspective; PCMs have the potential to offset or replace parts of an approximately twenty billion dolar electronics media market.

This class of materials represents yet another example where the pace of industry trumps the progress of basic science. In particular, the question concerning on optimal composition can be solved, probably at the industry pace, by brute force. One simply exhaust all physically reasonable compositions until the best emerges. The latter question, however, has proved to be a more difficult undertaking largely because it requires a more detailed understanding of every aspect of the system. From a basic physic stand-point, the phase-change phenomenon is more interesting and an understanding of it in these materials will provide an important step in developing predictive models for related materials.

(Bobela, D. C., Local bonding structure of tellurium and antimony in the phase change chalcogenides germanium-antimony-tellurium: A nuclear magnetic resonance study, pp.1-2)

3-Make or Buy: (Previous)(Better)

 Fundamentally, make or buy is about the choice of whether to carry out a particular process or activity within your own business or to buy it in from a supplier. In reality, this can take many forms: choice about making a particular small part of a complex larger products (for example, if we make turbine generators, should we make the ball bearings that go into them?), choices about system and subsystem manufacture (if we make cars, should we make the engine?), choices about which particular manufacturing processes to have in the company (if our manufacturing process requires a specialised heat treatment, should we beuy the plan tor use a specialises subcontractor?). Although the examples given are from manufacturing businesses, the same issues apply to other in or outscoring decisions.

The distinctive feature of manufacturing industry is the variety of processes involved and hence the frequency with which the issue is encountered, with the resulting greater scope for good or bad decisions to affect the business result.

(D. Probert, Developing a Make or Buy strategy for manufacturing business, p. 1,2)

MAKE OR BUY (New)(Business Decision)

Assembly simplification shades into the make or buy decision. Should a company make sub-assemblies or buy them? In part this turns on incremental cost. The total cost of making a sub-assembly in a company is irrelevant if a portion of those costs would be incurred anyway. An example of a cost that would be paid by the company whether a part was made or bought would be allocated overhead.

The simplest way to think of a make or buy decision is to compare the variable cost of manufacturing an item (direct labor, direct material and variable factory overhead) to the cost of purchasing the item plus  transportation in and import taxes if any.

Functional analysis can be used to analyze services, administrative functions or almost any element of company.

(Vance, D. E. Corporate Restructuring: From Cause Analysis to Execution, p.177)

4-Feature Mapping(Previous)

At initial general design stage, design feature are gradually increase, but there are some uncertain factors and new structure of the design was not decided. Because some design features have been decided and the other were not decided at conceptual stage, we propose that the information of not deciding can be supposed in reason or ignored. Then the known design feature scan be mapped into the cost features with direct mapping,projective mapping, and conjugate mapping. For some parts that have been manufactured in the past detail cost estimation method is used directly to obtain the cost value.

(Jardim R.,Roy R.,Staiger A.,Advances in concurrent engineering, page 77-78)

FEATURE MAPPING(New) (Better) (Design Process)

Feature models are domain dependent: When a part is designed by features, the resulting modes is usually not in form convenient for other applications, such as manufacturing process planning. Indeed, design features are stereotypical shapes related to a part’ function, its design intent, or the model construction methodology, whereas manufacturing features are stereotypical shapes that can be made by typical manufacturing operations. These two families of features are genuinely different. To transfer product information from a design-oriented feature model to a manufacturing-oriented model, it is necessary to transform the model from one viewpoint to another.This process is termed feature mapping.

(Shah, J. J., Mäntylä, M., Parametric and feature-based CAD/CAM: concepts, techniques, and applications, P. 219)

5-Groupware(Previous) 

Technological advances have increased the functionality of groupware solutions in the workplace. The role of computer supported collaboration will continue to redefine the strategy and culture of corporations worldwide. Companies are increasingly viewing groupware solutions as a competitive necessity. Achieving success in planning and implementing a groupware installation requires an organization to define communication goals in terms of corporate strategy and full support from all levels of management. Groupware is about people, whether in teams, organizations, or whole enterprises. This article attempts to define the groupware concept and present practical implications of a collaborative implementation in the workplace environment.

(Telematics and Informatics, Volume 15, Issues 1-2, February 1998, p. 85-101)

GROUPWARE(New)(Better)(Sotfware)

Groupware is software that uniquely enables organizations to communicate, to collaborate, and to coordinate key business processes. Groupware encompasses electronic mail, but goes far beyond messaging to act as an integrated platform for the development and deployment of a new class of client/server applications—applications that structure the flow of both structured and unstructured information in business relationships—among teams, across an enterprise, and between companies.

Groupware is so compelling because it allows businesses to create an organizational memory and share knowledge and expertise across time zones, geographies, and networks.It draws together the collective intelligence found in unstructured information sources like word processing documents, electronic mail messages, and faxes.Companies using groupware find that the barriers to high-performance teamwork that have plagued tham fall away. According to international Data Corporation, groupware signals the second wave in desktop computing.

(Info World,Volume 17, 29 May 1995, p.102)