System integration design in MEMS - A case study of micromachined load cell

One of the critical issues in large scale commercial exploitation of MEMS technology is its system integration. In MEMS, a system design approach requires integration of varied and disparate subsystems with one of a kind interface. The physical scales as well as the magnitude of signals of various subsystems vary widely. Known and proven integration techniques often lead to considerable loss in advantages the tiny MEMS sensors have to offer. Therefore, it becomes imperative to think of the entire system at the outset, at least in terms of the concept design. Such design entails various aspects of the system ranging from selection of material, transduction mechanism, structural configuration, interface electronics, and packaging. One way of handling this problem is the system-in-package approach that uses optimized technology for each function using the concurrent hybrid engineering approach. The main strength of this design approach is the fast time to prototype development. In the present work, we pursue this approach for a MEMS load cell to complete the process of system integration for high capacity load sensing. The system includes; a micromachined sensing gauge, interface electronics and a packaging module representing a system-in-package ready for end characterization. The various subsystems are presented in a modular stacked form using hybrid technologies. The micromachined sensing subsystem works on principles of piezo-resistive sensing and is fabricated using CMOS compatible processes. The structural configuration of the sensing layer is designed to reduce the offset, temperature drift, and residual stress effects of the piezo-resistive sensor. ANSYS simulations are carried out to study the effect of substrate coupling on sensor structure and its sensitivity. The load cell system has built-in electronics for signal conditioning, processing, and communication, taking into consideration the issues associated with resolution of minimum detectable signal. The packaged system represents a compact and low cost solution for high capacity load sensing in the category of compressive type load sensor.

Integration or disintegration? Human resource implications of a common corporate language decision in a crossborder merger

The primary purpose of introducing a common corporate language in crossborder mergers is to integrate two previously separate organizations and facilitate communication. However, the present case study of a cross-border merger between two Nordic banks shows that the common corporate language decision may have disintegrating effects, particularly at organizational levels below top management. We identify such effects on performance appraisal, language training and management development, career paths, promotion and key personnel. Our findings show that top management needs to work through the consequences of the language decision upon those who are expected to make such a decision work.

Examining effectiveness of an immigrant labor market integration intervention. The role of acculturation, discrimination, self-efficacy, outcome expectances, action and coping planning.

The designing of effective intervention tools to improve immigrants’ labor market integration remains an important topic in contemporary Western societies. This study examines whether and how a new intervention tool, Working Life Certificate (WLC), helps unemployed immigrants to find employment and strengthen their belief of their vocational skills. The study is based on quantitative longitudinal survey data from 174 unemployed immigrants of various origins who participated in the pilot phase of WLC examinations in 2009. Surveys were administered in three waves: before the test, right after it, and three months later. Although it is often argued that the unemployment among immigrants is due either to their lack of skills and cultural differences or to discrimination in recruitment, scholars within social psychology of behavior change argue that the best way of helping people to achieve their goals (e.g. finding employment) is to build up their sense of self-efficacy, alter their outcome expectances in a more positive direction or to help them to construct more detailed action and coping plans. This study aims to shed light on the role of these concepts in immigrants’ labor market integration. The results support the theories of behavior change moderately. Having positive expectances regarding the outcomes of various job search behaviors was found to predict employment in the future. Together with action and coping planning it also predicted increase in job search behavior. The intervention, WLC, was able to affect participants’ self-efficacy, but contrary to expectations, self-efficacy was found not to be related to either job search behavior or future labor market status. Also, perceived discrimination did not explain problems in finding employment, but hints of subtle or structural discrimination were found. Adoption of Finnish work culture together with strong family culture was found to predict future employment. Hence, in this thesis I argue that awarding people diplomas should be preferred in immigrant integration training as it strengthens people’s sense of self-efficacy. Instead of teaching new information, more attention should be directed at changing people’s outcome expectances in a more positive direction and helping them to construct detailed plans on how to achieve their goals.

An accurate numerical integration scheme for finite rotations using rotation vector parametrization

A numerical integration procedure for rotational motion using a rotation vector parametrization is explored from an engineering perspective by using rudimentary vector analysis. The incremental rotation vector, angular velocity and acceleration correspond to different tangent spaces of the rotation manifold at different times and have a non-vectorial character. We rewrite the equation of motion in terms of vectors lying in the same tangent space, facilitating vector space operations consistent with the underlying geometric structure. While any integration algorithm (that works within a vector space setting) may be used, we presently employ a family of explicit Runge-Kutta algorithms to solve this equation. While this work is primarily motivated out of a need for highly accurate numerical solutions of dissipative rotational systems of engineering interest, we also compare the numerical performance of the present scheme with some of the invariant preserving schemes, namely ALGO-C1, STW, LIEMIDEA] and SUBCYC-M. Numerical results show better local accuracy via the present approach vis-a-vis the preserving algorithms. It is also noted that the preserving algorithms do not simultaneously preserve all constants of motion. We incorporate adaptive time-stepping within the present scheme and this in turn enables still higher accuracy and a `near preservation' of constants of motion over significantly longer intervals. (C) 2010 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

Integration of aquaculture and agriculture: a route to sustainable farming systems

The integration of agriculture and aquaculture as a means of intensifying resource use and improving the productivity of many current farming practices in Southeast Asian and African countries is discussed. A brief account is given of work undertaken by ICLARM in Malawi and India regarding the improved use of marginal lands to integrate crops, vegetables, trees, livestock and fish, outlining also the various problems involved in the extension of such integrated fish farming systems.

Discovering transcriptional modules by Bayesian data integration.

MOTIVATION: We present a method for directly inferring transcriptional modules (TMs) by integrating gene expression and transcription factor binding (ChIP-chip) data. Our model extends a hierarchical Dirichlet process mixture model to allow data fusion on a gene-by-gene basis. This encodes the intuition that co-expression and co-regulation are not necessarily equivalent and hence we do not expect all genes to group similarly in both datasets. In particular, it allows us to identify the subset of genes that share the same structure of transcriptional modules in both datasets. RESULTS: We find that by working on a gene-by-gene basis, our model is able to extract clusters with greater functional coherence than existing methods. By combining gene expression and transcription factor binding (ChIP-chip) data in this way, we are better able to determine the groups of genes that are most likely to represent underlying TMs. AVAILABILITY: If interested in the code for the work presented in this article, please contact the authors. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Framework for integration of informal waste management sector with the formal sector in Pakistan.

Historically, waste pickers around the globe have utilised urban solid waste as a principal source of livelihood. Formal waste management sectors usually perceive the informal waste collection/recycling networks as backward, unhygienic and generally incompatible with modern waste management systems. It is proposed here that through careful planning and administration, these seemingly troublesome informal networks can be integrated into formal waste management systems in developing countries, providing mutual benefits. A theoretical framework for integration based on a case study in Lahore, Pakistan, is presented. The proposed solution suggests that the municipal authority should draw up and agree on a formal work contract with the group of waste pickers already operating in the area. The proposed system is assessed using the integration radar framework to classify and analyse possible intervention points between the sectors. The integration of the informal waste workers with the formal waste management sector is not a one dimensional or single step process. An ideal solution might aim for a balanced focus on all four categories of intervention, although this may be influenced by local conditions. Not all the positive benefits will be immediately apparent, but it is expected that as the acceptance of such projects increases over time, the informal recycling economy will financially supplement the formal system in many ways.

Framework for integration of informal waste management sector with the formal sector in Pakistan

Historically, waste pickers around the globe have utilised urban solid waste as a principal source of livelihood. Formal waste management sectors usually perceive the informal waste collection/recycling networks as backward, unhygienic and generally incompatible with modern waste management systems. It is proposed here that through careful planning and administration, these seemingly troublesome informal networks can be integrated into formal waste management systems in developing countries, providing mutual benefits. A theoretical framework for integration based on a case study in Lahore, Pakistan, is presented. The proposed solution suggests that the municipal authority should draw up and agree on a formal work contract with the group of waste pickers already operating in the area. The proposed system is assessed using the integration radar framework to classify and analyse possible intervention points between the sectors. The integration of the informal waste workers with the formal waste management sector is not a one dimensional or single step process. An ideal solution might aim for a balanced focus on all four categories of intervention, although this may be influenced by local conditions. Not all the positive benefits will be immediately apparent, but it is expected that as the acceptance of such projects increases over time, the informal recycling economy will financially supplement the formal system in many ways. © The Author(s) 2013.

Integration of a photonic crystal polarization beam splitter and waveguide bend

In this work, we present the design of an integrated photonic-crystal polarization beam splitter (PC-PBS) and a low-loss photonic-crystal 60 waveguide bend. Firstly, the modal properties of the PC-PBS and the mechanism of the low-loss waveguide bend are investigated by the two-dimensional finite-difference time-domain (FDTD) method, and then the integration of the two devices is studied. It shows that, although the individual devices perform well separately, the performance of the integrated circuit is poor due to the multi-mode property of the PC-PBS. By introducing deformed airhole structures, a single-mode PC-PBS is proposed, which significantly enhance the performance of the circuit with the extinction ratios remaining above 20dB for both transverse-electric (TE) and transverse-magnetic (TM) polarizations. Both the specific result and the general idea of integration design are promising in the photonic crystal integrated circuits in the future. (C) 2009 Optical Society of America

Monolithic Integration of a Widely Tunable Laser with SOA Using Quantum-Well Intermixing

This paper presents an SG-DBR with a monolithically integrated SOA fabricated using quantum-well intermixing （QWI） for the first time in mainland China. The wavelength tuning range covers 33nm and the output power reaches 10mW with an SOA current of 50mA. The device can work at available channels with SMSR over 35dB.

Symbolic Integration

SIN and SOLDIER are heuristic programs in LISP which solve symbolic integration problems. SIN (Symbolic INtegrator) solves indefinite integration problems at the difficulty approaching those in the larger integral tables. SIN contains several more methods than are used in the previous symbolic integration program SAINT, and solves most of the problems attempted by SAINT in less than one second. SOLDIER (SOLution of Ordinary Differential Equations Routine) solves first order, first degree ordinary differential equations at the level of a good college sophomore and at an average of about five seconds per problem attempted. The differences in philosophy and operation between SAINT and SIN are described, and suggestions for extending the work presented are made.

Grid integration of wave energy & generic modelling of ocean devices for power system studies

The work presented in this thesis covers four major topics of research related to the grid integration of wave energy. More specifically, the grid impact of a wave farm on the power quality of its local network is investigated. Two estimation methods were developed regarding the flicker level Pst generated by a wave farm in relation to its rated power as well as in relation to the impedance angle ψk of the node in the grid to which it is connected. The electrical design of a typical wave farm design is also studied in terms of minimum rating for three types of costly pieces of equipment, namely the VAr compensator, the submarine cables and the overhead line. The power losses dissipated within the farm's electrical network are also evaluated. The feasibility of transforming a test site into a commercial site of greater rated power is investigated from the perspective of power quality and of cables and overhead line thermal loading. Finally, the generic modelling of ocean devices, referring here to both wave and tidal current devices, is investigated.

Hybrid integration and packaging of grating-coupled silicon photonics

This thesis covers both the packaging of silicon photonic devices with fiber inputs and outputs as well as the integration of laser light sources with these same devices. The principal challenge in both of these pursuits is coupling light into the submicrometer waveguides that are the hallmark of silicon-on-insulator (SOI) systems. Previous work on grating couplers is leveraged to design new approaches to bridge the gap between the highly-integrated domain of silicon, the Interconnected world of fiber and the active region of III-V materials. First, a novel process for the planar packaging of grating couplers with fibers is explored in detail. This technology allows the creation of easy-to-use test platforms for laser integration and also stands on its own merits as an enabling technology for next-generation silicon photonics systems. The alignment tolerances of this process are shown to be well-suited to a passive alignment process and for wafer-scale assembly. Furthermore, this technology has already been used to package demonstrators for research partners and is included in the offerings of the ePIXfab silicon photonics foundry and as a design kit for PhoeniX Software’s MaskEngineer product. After this, a process for hybridly integrating a discrete edge-emitting laser with a silicon photonic circuit using near-vertical coupling is developed and characterized. The details of the various steps of the design process are given, including mechanical, thermal, optical and electrical steps. The interrelation of these design domains is also discussed. The construction process for a demonstrator is outlined, and measurements are presented of a series of single-wavelength Fabry-Pérot lasers along with a two-section laser tunable in the telecommunications C-band. The suitability and potential of this technology for mass manufacture is demonstrated, with further opportunities for improvement detailed and discussed in the conclusion.

Performance evaluation of the register insertion protocol for voice-data integration

The performance of the register insertion protocol for mixed voice-data traffic is investigated by simulation. The simulation model incorporates a common insertion buffer for station and ring packets. Bandwidth allocation is achieved by imposing a queue limit at each node. A simple priority scheme is introduced by allowing the queue limit to vary from node to node. This enables voice traffic to be given priority over data. The effect on performance of various operational and design parameters such as ratio of voice to data traffic, queue limit and voice packet size is investigated. Comparisons are made where possible with related work on other protocols proposed for voice-data integration. The main conclusions are: (a) there is a general degradation of performance as the ratio of voice traffic to data traffic increases, (b) substantial improvement in performance can be achieved by restricting the queue length at data nodes and (c) for a given ring utilisation, smaller voice packets result in lower delays for both voice and data traffic.

Policy-centric integration and dynamic composition of autonomic computing techniques

This paper presents innovative work in the development of policy-based autonomic computing. The core of the work is a powerful and flexible policy-expression language AGILE, which facilitates run-time adaptable policy configuration of autonomic systems. AGILE also serves as an integrating platform for other self-management technologies including signal processing, automated trend analysis and utility functions. Each of these technologies has specific advantages and applicability to different types of dynamic adaptation. The AGILE platform enables seamless interoperability of the different technologies to each perform various aspects of self-management within a single application. The various technologies are implemented as object components. Self-management behaviour is specified using the policy language semantics to bind the various components together as required. Since the policy semantics support run-time re-configuration, the self-management architecture is dynamically composable. Additional benefits include the standardisation of the application programmer interface, terminology and semantics, and only a single point of embedding is required.