Complex Process Chains Research Articles

Complex Process Chains for Manufacturing of Invisible Displays Integrated in Bulk Metal Panels

Information displays that are invisible in the inactive state, and concealed in transparent or semi-transparent materials such as plastic or glass, are commercially available. However, if displays were to be invisibly integrated in bulk metal panels, very few known solutions exist. This has to do with the fact that very thin (20–50 nm) metal layers are required for the light to penetrate. This paper describes the realisation of displays integrated in bulk metal panels through the development and optimisation of complex process chains involving laser micromachining, micro electrochemical machining and selective anodising. An extensive experimental investigation of the single processes as well as their sequential combination is reported, and the capabilities of the different process chains are demonstrated.

Optical Measuring Technologies in Sheet Metal Processing

During recent years, optical measuring technologies in sheet metal forming and tooling have been used more and more in the industry. Main applications are the digitizing of metal sheet parts and tools, forming analysis of metal sheets as well as the determination of material properties. Good interfaces to conventional CAD/CAM and numerical simulation systems made such optical measuring systems a part of complex process chains. These process chains mainly focus on optimizing the development of products and production processes and on improving the product quality. Using optical systems considerably decreases the development time for products and production while improving the quality.

The PDF projection theorem and the class-specific method

We present the theoretical foundation for optimal classification using class-specific features and provide examples of its use. A new probability density function (PDF) projection theorem makes it possible to project probability density functions from a low-dimensional feature space back to the raw data space. An M-ary classifier is constructed by estimating the PDFs of class-specific features, then transforming each PDF back to the raw data space where they can be fairly compared. Although statistical sufficiency is not a requirement, the classifier thus constructed becomes equivalent to the optimal Bayes classifier if the features meet sufficiency requirements individually for each class. This classifier is completely modular and avoids the dimensionality curse associated with large complex problems. By recursive application of the projection theorem, it is possible to analyze complex signal processing chains. We apply the method to feature sets, including linear functions of independent random variables, cepstrum, and Mel cepstrum. In addition, we demonstrate how it is possible to automate the feature and model selection process by direct comparison of log-likelihood values on the common raw data domain.

다부품 시스템의 적용을 위한 전과정평가 기법

A multi-component system like an automobile is composed of several thousands of components and considerable parts of them are fabricated and manufactured outside of the product manufacturers. The manufacturing and assembly of these products represents a complex chain of processes controlled by a network of original equipment manufacturers(OEMs) and suppliers. This makes it difficult to get precise information of a great number of components which are required in order to carry out an LCA study of a multi-component product system. In this paper, a practical and systematic LCA methodology for a multi-component system, with which a time and cost effective study can be carried out for a highly complex system is developed. The life cycle inventory for a multi-component system is established based on the ecological data of modules and sub-modules by using a combination of top-down and bottom-up approaches.

Laser–solid interaction in the femtosecond time regime

Modification of the surface structure of solid materials by laser radiation involves a complex chain of processes. The first step is the deposition of a certain amount of optical energy in the material. The character of the material excitation is strongly dependent on the laser pulse duration. With the use of ultrashort laser pulses non-equilibrium energy distributions with large excess population in the excited states can be produced. The distinct physical processes which come into play in laser–solid interaction on the ultrafast time scale open new routes of modifying the structure and the morphology of materials and offer interesting perspectives in laser materials processing.

Behavioral and Developmental Aspects of Immunity

Considerable evidence is accumulating which demonstrates a relationship between immune function and behavioral states such as object loss or depression. Findings have been described using animal and clinical models, and a complex chain of biological and psychological processes may be involved. Further research on behavioral, central nervous system, and immune interactions in childhood is needed and is especially important since the developing immune system may be particularly susceptible to behavioral effects. Effects on the immune system in early life may have profound long-term effects on immune capacity.

Stress and immunomodulation: the role of depression and neuroendocrine function

Considerable evidence demonstrating a relationship between stress and immune function is accumulating, and a complex chain of biologic and psychologic processes are involved. An extensive network of central nervous system and endocrine system processes may be involved in the modulation of the immune system in response to stressors.

Cortical Changes in Acipenserid Eggs during Fertilization and Artificial Activation

ABSTRACT In the complex chain of interrelated processes which make up the early changes in the egg during activation (see Tyler, 1941, 1955; Runnström, 1952; Rothschild, 1956; T. Yamamoto, 1956; Allen, 1958) many phenomena are still unclear : for example, the problem of the fertilization impulse, the rate of its spread, and its relationship with the other changes in the egg; the problem of the origin of the perivitelline space colloid and of its relation to the material of the cortical granules (Runnström, 1952; Rothschild, 1956; Allen, 1958). The main objects of investigation have hitherto been the eggs of sea urchins and, to a lesser extent, of teleost fishes, so that a danger exists that the sequence of phenomena characteristic of these eggs may be supposed to hold generally. Acipenserid eggs, because of certain peculiarities of their structure and development, are a suitable object for studies of this kind.