CLADP - THE CAMBRIDGE LINEAR ANALYSIS AND DESIGN PROGRAMS USER REFERENCE MANUAL (4TH ISSUE: APRIL 1983).

CLADP is an engineering software program developed at Cambridge University for the interactive computer aided design of feedback control systems. CLADP contains a wide range of tools for the analysis of complex systems, and the assessment of their performance when feedback control is applied, thus enabling control systems to be designed to meet difficult performance objectives. The range of tools within CLADP include the latest techniques in the field whose central theme is the extension of classical frequency domain concepts (well known and well proven for single loop systems) to multivariable or multiloop systems, and by making extensive use of graphical presentation information is provided in a readily understood form.

The influence of peel angle on the mechanics of peeling flexible adherends with arbitrary load-extension characteristics

The peel test is commonly used to determine the strength of adhesive joints. In its simplest form, a thin flexible strip which has been bonded to a rigid surface is peeled from the substrate at a constant rate and the peeling force which is applied to the debonding surfaces by the tension in the tape is measured. Peeling can be carried out with the peel angle, i.e. the angle made by the peel force with the substrate surface, from any value above about 10° although peeling tests at 90 and 180° are most common. If the tape is sufficiently thin for its bending resistance to be negligibly small then as well as the debonding or decohesion energy associated with the adhesive in and around the point of separation, the relation between the peeling force and the peeling angle is influenced both by the mechanical properties of the tape and any pre-strain locked into the tape during its application to the substrate. The analytic solution for a tape material which can be idealised as elastic perfectly-plastic is well established. Here, we present a more general form of analysis, applicable in principle to any constitutive relation between tape load and tape extension. Non-linearity between load and extension is of increasing significance as the peel angle is decreased: the model presented is consistent with existing equations describing the failure of a lap joint between non-linear materials. The analysis also allows for energy losses within the adhesive layer which themselves may be influenced by both peel rate and peel angle. We have experimentally examined the application of this new analysis to several specific peeling cases including tapes of cellophane, poly-vinyl chloride and PTFE. © 2005 Elsevier Ltd. All rights reserved.

Advanced thermal processing of semiconductor materials in the msec-range

This paper reviews the advances that flash lamp annealing brings to the processing of the most frequently used semiconductor materials, namely silicon and silicon carbide, thus enabling the fabrication of novel microelectronic structures and materials. The paper describes how such developments can translate into important practical applications leading to a wide range of technological benefits. Opportunities in ultra-shallow junction formation, heteroepitaxial growth of thin films of cubic silicon carbide on silicon, and crystallization of amorphous silicon films, along with the technical reasons for using flash lamp annealing are discussed in the context of state-of-the-art materials processing. © 2005 IEEE.

The oxidation of CH2O in the intermediate temperature range (943-995 K)

New atmospheric pressure flow reactor data on the oxidation of formaldehyde in the temperature range 943-995 K and over equivalence ratios from 0.013 to 36.7 are reported and discussed. A detailed mechanism assembled from previously published results produced acceptable agreement with the experimental data for the fuel-lean conditions, but failed to predict results for oxidative pyrolysis. Analysis or the very fuel-lean conditions, but failed to modelling results are principally sensitive to CH2O+HO2→HCO+H2O2 (6) and H2O2 +M→OH+OH+M (33). Whereas the specific rate of each reaction cannot be independently determined, it is found that the product k33.k6 is a well defined function of temperature: (3.4±3.0).1028 exp(-(26,800±400)/T). Inadequacies in the mechanism which may be responsible for the disagreement under fuel-rich conditions are discussed. © 1991 Combustion Institute.

Fabrication and testing of a high resolution extensometer based on resonant MEMS strain sensors

A novel type of linear extensometer with exceptionally high resolution of 4 nm based on MEMS resonant strain sensors bonded on steel and operating in a vacuum package is presented. The tool is implemented by means of a steel thin bar that can be pre-stressed in tension within two fixing anchors. The extension of the bar is detected by using two vacuum-packaged resonant MEMS double- ended tuning fork (DETF) sensors bonded on the bar with epoxy glue, one of which is utilized for temperature compensation. Both sensors are driven by a closed loop self-oscillating transresistance amplifier feedback scheme implemented on a PCB (Printed Circuit Board). On the same board, a microcontroller-based frequency measurement circuit is also implemented, which is able to count the square wave fronts of the MEMS oscillator output with a resolution of 20 nsec. The system provides a frequency noise of 0.2 Hz corresponding to an extension resolution of 4 nm for the extensometer. Nearly perfect temperature compensation of the frequency output is achieved in the temperature range 20-35 C using the reference sensor. © 2011 IEEE.

Suitable sites for sustainable aquaculture development in Mymensingh, Bangladesh: A GIS methodological perspective

A GIS study was carried out to find out the sites suitable for aquaculture in Mymensingh region. A number of criteria were selected for GIS modeling followed by the approach of Kapetsky (1994). The criteria were developed from a range of existing data sources such as, surface and underground water level, availability of feed ingredients and animal wastes, sources of fish fry, market facilities, extension support and communication facilities for aquaculture development. The data were located, collected and compiled from different GOs and NGOs located in the region along with primary data from the field survey wherever necessary and then prepared for computer analyses. Using the database, a series of GIS models were developed in order to ascertain and prioritize the most suitable areas for aquaculture development in the region. Out of total 407,528 ha available lands in the region, the study identified 99,415 ha very suitable and 302,754 ha moderately suitable for aquaculture promotion. Result of the study is indicative to the modeling power of GIS for aquaculture application and could be used to refine the models in future, particularly if it is supported with further detail field data. To get a more concrete and complete model, detailed study should be made available on the availability of mustard oil cake, rice bran, wheat bran, and usable animal and urban wastes that could be used as low-cost feed for sustainable aquaculture.

Towards a mathematical system for extension education

A system of equations describing the relationship of change agent in extension education and client (e.g. a leader of a local community) is presented. The main task of the former is to ensure that he is able to transfer information to the latter, also learning difficulties involved and passing them into institutions of higher learning.

Towards a mathematical system for extension education - II

A brief description is given of a mathematical model for use in extension education regarding fisheries in developing countries.

Study of the relative effectiveness of extension methods in educating fisherwomen

Three experimental groups from three different fishing villages were selected and administered with three extension treatments on two messages, namely, production of fish wafers and fish pickles. There was a significant knowledge gain in the subjects taught through different extension methods. It was observed that lecture aided with slides induced maximum knowledge followed by lecture aided with charts and lecture alone. Among all, the young and highly educated women gained maximum knowledge.

Social organization and range use in the Yunnan snub-nosed monkey Rhinopithecus bieti

We studied social organization, behavior, and range use of the Yunnan snub-nosed monkey (Rhinopithecus bieti) at Wuyapiya (99 degrees 12'E, 28 degrees 30'N, the People's Republic of China) over 12 months between May 1992 and June 1994. The Wuyapiya band contained greater than or equal to 175 members and had two levels of social organization. At one level, the monkeys formed multifemale, one-male units (OMUs) similar to those of many other colobines. At another level, 15 to 18 OMUs traveled together in a cohesive band. Unlike the bands of other species of Rhinopithecus, the Wuyapiya band of R. bieti did not show seasonal fission-fusion, although some social behavior, such as male-male aggression, was seasonal. With regard to range use, the Wuyapiya band had a large home range and long daily travel distances compared with other colobines. Minimum range size in 1 year at Wuyapiya is 16.25 km(2), although there is no asymptote for range size as a function of observation time. Range size for the Wuyapiya band is 25.25 km(2) over the 2-year study and appeared to cover 100 km(2) between 1985 and 1994. The primary food of R. bieti at Wuyapiya is lichens, which are ubiquitous in fir frees. The multitiered social organization of R. bieti appears to result from the interaction of food resource characters with the forces of mate competition, with band sizes based on female responses to the spatial and temporal characteristics of lichens and subdivisions within bands based on male competition for mates.