Optimal cooperation between external criterion and data division in GMDH

The problem of cooperation between external criterion and data division is important for application and development of group method of data handling (GMDH) theory. Based on research of ‘critical noise level’ and ‘noise immunity’, this article presents the concept of ‘expected critical noise level’. The relationship between ‘expected critical noise level’ and both prediction set and model structure is expressed by a formula. According to ‘expected critical noise level’, a selection method is designed, which is able to obtain an optimal cooperation between external criterion and data division in GMDH. Finally, the corresponding algorithm and an example are given.     

Behavior of micro-polar flow due to linear stretching of porous sheet with injection and suction

The boundary layer flow of a micro-polar fluid due to a linearly stretching sheet is investigated. The influence of various flow parameters like ‘suction and injection velocity through the porous surface’, ‘viscosity parameter causing the coupling of the micro-rotation field and the velocity field’ and ‘vortex viscosity parameter’ on ‘shear stress at the surface’, ‘fluid velocity’ and ‘micro-rotation’ are studied. The governing equations of the transformed boundary layer are solved analytically using homotopy analysis method (HAM). The convergence of the obtained series solutions is explicitly studied and a proper discussion is given for the obtained results. Comparison between the HAM and numerical solutions showed excellent agreement.     

Closed-loop eigenstructure assignment by state feedback in multivariable linear systems with slow and fast modes

It is shown that the recent results of Moore (1976) and Porter and D'Azzo (1977) can be readily extended so as to provide a computationally attractive method of closed-loop eigenstructure assignment by state feedback in multivariable systems with ‘ slow ’ and ‘ fast ’ modes. The general results are illustrated by designing a state-feedback controller for a third-order system with ‘ slow ’ and ‘ fast ’ modes which assigns asymptotically the entire closed-loop eigenstructure as characterized by both ‘ slow ’ and ‘ fast ’ eigenvalues and eigenvectors.     

Bi-objective min-flow problem with capacity and flow constraints

A network flow algorithm for a bi-criteria version of the manpower scheduling and resource allocation problem is developed. In such a study it is desired to find the ‘minimum’ total ‘flow’ through the network, where ‘flow’ is represented by a two-component cost vector and ‘minimum’ is interpreted in the sense of a vector-minimum. Thus, a set of non-dominated solutions is obtained. The method efficiently generates both individual (criterion) optima and bi-criteria solutions in a single pass. A simple example is presented.     

Closed loop hierarchical control for river pollution

In this paper a feedback solution is obtained for a two polluter river pollution control problem using a hierarchial method. The hierarchial optimisation algorithm uses the continuous time ‘No Delay’, ‘Pure Delay’ and ‘Distributed Delay’ models of the river Cam near Cambridge. All the calculations are done off-line within a decentralised computational structure. The resulting constant gains provide optimal feedback control for any initial condition and this control can be implemented on-line. The method is also demonstrated on the three polluter ‘Distributed Delay’ model.     

Knowledge acquisition method for conceptual design based on value engineering and axiomatic design theory

A method for acquiring conceptual design knowledge in physical systems is proposed and implemented based on EBL (explanation-based learning), ‘value engineering methodologies’ and ‘axiomatic design approaches’. In this method, the structural features of designed objects are analysed to yield a systematic explanation of how they function and attain their design goals and why they are used for attaining the goals.The ‘how’ explanation results in a generalized version of the functional diagram used in value engineering from which various levels of general design knowledge can be extracted. The quality of the extracted knowledge is then discussed with reference to its mode of acquisition.The ‘why’ explanation yields a deeper understanding of the designed objects from which we can extract meta-planning or strategic knowledge for selecting rational plans from among other possible alternatives. This explanation is obtained by regarding the object in question as being the result of strategically rational decisions and actions which are subject to the ‘design axioms’.     

An entropy target-point approach to multiobjective programming

In this paper, we present a method for solving multiple objective programming problems. The method can be interpreted as a ‘distance’ method, i.e. the method minimizes the ‘distance’ from a target point specified by the decision maker. The auxiliary ‘distance’ objective we use in our method is the entropy function. With this choice of auxiliary objective, we obtain a computationally efficient method. This algorithmic efficiency is especially emphasized when the method is to be used in an interactive scheme where the auxiliary problem has to be solved repeatedly for a number of different target points. Another attractive feature of the choice of an entropy auxiliary objective function is that it generates stable solutions.     

Constructing composite indicators with imprecise data: A proposal

This paper focuses on the construction of a composite indicator for the knowledge based economy, using imprecise data. Specifically, for some indicators we only have information on the interval within which the true value is believed to lie. The proposed approach is based on the Data Envelopment Analysis literature. Given the setting of evaluating countries, this paper discerns a ‘strong country in weak environment’ and ‘weak country in strong environment’ scenario resulting in respectively an upper and lower bound on countries’ performance. Accordingly, we derive a classification of ‘benchmark countries’, ‘potential benchmark countries’, and ‘countries open to improvement’. We illustrate our method with data on the knowledge economy.     

汉字输入键盘设计方法的研究——兼论标准汉字双拼键盘的设计

本文提出了汉字‘权值’的概念, 并以汉字‘权值’做为衡量标准, 以汉字输入双拼键盘的设计为例, 对如何设计一个优秀的汉字输入键盘的方法进行了详细研究。 同时指出,‘权值’概念的提出同样适合其它类型汉字编码方案的键盘设计。     

Identification and estimation of discrete state-vector models with stochastic inputs

The study deals with the identification and estimation of the unknown parameters of an ‘extended’ state-vector model, in which stochastic input variables are treated as ‘state’-variables and the observed input-values as ‘output’-values of the model.A parameter identifiability criterion, based on Fisher's information matrix, is applied to the model and a general ML-estimation procedure is given. If a certain restriction on the covariance-matrix of the state-vector is placed, the ML-procedure simplifies and coincides with an operational method, called the Lisrel procedure. This procedure provides also a test for parameter identifiability.     

Spatial pattern in sections of human muscle

One feature of certain types of abnormal human muscle is the presence of large clusters of fibers of the same type. Such ‘type grouping’ in a sample of muscle biopsy is important because it indicates a history of damage to the nerves supplying the individual muscle fibres. The ‘distance’ between two fibres is defined as the minimum number of fibre-fibre boundaries in any path between them. This papers describes a method of assessing fibre type grouping based on a family of co-occurrence matrices, one for each positive distance between fibres, and illustrates its application on two samples of sections of muscle biopsy judged by a human observer to show ‘normal’ and ‘abnormal’ amounts of ‘type grouping’.     

Optimal Switching In Structured Treatment Interruption For Hiv Therapy

This paper proposes ‘optimal switching control during structured treatment interruption,’ which switches RTI and PI to reduce medication and establish long‐term immune response against HIV. The proposed method is compared with ‘optimized STI’ through numerical simulation. The proposed method results in a more rapid increase of CTLp, and thus total drug intake and the therapy period are reduced. HIV treatment simulation results are analyzed in terms of controllability. Due to the effect of PI, ‘optimal switching control during STI’ can achieve greater controllability more quickly than ‘optimized STI.’     

Multiplication by integer constants

Methods are given for finding a sequence of ‘add’, ‘subtract’ and ‘shift’ instructions to multiply the contents of a register by an integer constant. Each method generalizes the previous one and requires only a few intermediate or scratch registers. A variation of the last method is used in the PL.8 compiler and uses an unnoticeable amount of the overall compile time. Some statistics roughly indicating the effectiveness of the methods are presented.     

‘Truncate,replicate, sample’: A method for creating integer weights for spatial microsimulation

Iterative proportional fitting (IPF) is a widely used method for spatial microsimulation. The technique results in non-integer weights for individual rows of data. This is problematic for certain applications and has led many researchers to favour combinatorial optimisation approaches such as simulated annealing. An alternative to this is ‘integerisation’ of IPF weights: the translation of the continuous weight variable into a discrete number of unique or ‘cloned’ individuals. We describe four existing methods of integerisation and present a new one. Our method – ‘truncate, replicate, sample’ (TRS) – recognises that IPF weights consist of both ‘replication weights’ and ‘conventional weights’, the effects of which need to be separated. The procedure consists of three steps: (1) separate replication and conventional weights by truncation; (2) replication of individuals with positive integer weights; and (3) probabilistic sampling. The results, which are reproducible using supplementary code and data published alongside this paper, show that TRS is fast, and more accurate than alternative approaches to integerisation.     

Variation in upper limb posture and movement during word processing with and without mouse use

Work postures and movements of the upper limb were analysed for 12 ‘mouse’ operators and 12 ‘non-mouse’ computer operators employed in word-processing work. Measurements were carried out during correction of a given text. ‘Mouse’ operators spent 64% of the working time with the operative wrist deviating more than 15° towards the ulnar side, while ‘non-mouse’ operators spent 96% of the time with the corresponding wrist in neutral position towards radial deviation. The rotation in the shoulder was at all times in neutral position towards inward rotation for ‘non-mouse’ operators, while ‘mouse’ operators worked 81% of the time with the shoulder rotated outward more than 30°. ‘Mouse’ operators corrected a longer text during the given time. Our observations showed long periods of strenuous working postures for ‘mouse’ operators compared to ‘non-mouse’ operators. We believe that further investigations need to be carried out on the effects of word-processing techniques and to develop ergonomic work station designs for the ‘mouse’ and other non-keyboard input devices.     

The discrete strain gap method and membrane locking

The discrete shear gap (DSG) method, initially proposed for the elimination of transverse shear locking in plate and shell finite elements, is extended to a more general concept, rephrasing ‘DSG’ as ‘discrete strain gap’. We focus on the application of the method to the problem of membrane locking in beam and shell finite elements in the present paper. It turns out that a straightforward extension of the original DSG method is suitable to avoid membrane locking for both triangles and quadrilaterals. Moreover, there are strong indications that the presented idea includes the potential for a general formulation of locking-free structural finite elements, equally well suited for beams, plates, shells and solids.     

Algorithmic risk assessment policing models: lessons from the Durham HART model and ‘Experimental’ proportionality

As is common across the public sector, the UK police service is under pressure to do more with less, to target resources more efficiently and take steps to identify threats proactively; for example under risk-assessment schemes such as ‘Clare’s Law’ and ‘Sarah’s Law’. Algorithmic tools promise to improve a police force’s decision-making and prediction abilities by making better use of data (including intelligence), both from inside and outside the force. This article uses Durham Constabulary’s Harm Assessment Risk Tool (HART) as a case-study. HART is one of the first algorithmic models to be deployed by a UK police force in an operational capacity. Our article comments upon the potential benefits of such tools, explains the concept and method of HART and considers the results of the first validation of the model’s use and accuracy. The article then critiques the use of algorithmic tools within policing from a societal and legal perspective, focusing in particular upon substantive common law grounds for judicial review. It considers a concept of ‘experimental’ proportionality to permit the use of unproven algorithms in the public sector in a controlled and time-limited way, and as part of a combination of approaches to combat algorithmic opacity, proposes ‘ALGO-CARE’, a guidance framework of some of the key legal and practical concerns that should be considered in relation to the use of algorithmic risk assessment tools by the police. The article concludes that for the use of algorithmic tools in a policing context to result in a ‘better’ outcome, that is to say, a more efficient use of police resources in a landscape of more consistent, evidence-based decision-making, then an ‘experimental’ proportionality approach should be developed to ensure that new solutions from ‘big data’ can be found for criminal justice problems traditionally arising from clouded, non-augmented decision-making. Finally, this article notes that there is a sub-set of decisions around which there is too great an impact upon society and upon the welfare of individuals for them to be influenced by an emerging technology; to an extent, in fact, that they should be removed from the influence of algorithmic decision-making altogether.     

A Sequential Element Rejection and Admission (SERA) method for compliant mechanisms design

A Sequential Element Rejection and Admission (SERA) method to design compliant mechanisms with topology optimization techniques is presented in this work. This procedure allows material to flow between two different material models: ‘real’ and ‘virtual’. The method works with two separate criteria for the rejection and admission of elements to efficiently achieve the optimum design. The SERA method overcomes the problems encountered by the ESO method when used to design compliant mechanisms. Three benchmark problems are presented to show the validity and robustness of the SERA method to design complaint mechanisms, regardless of the design parameters chosen.     

A note on the numerical solution of the one-line model

Both explicit and implicit time-stepping finite difference schemes are well-known techniques for the numerical solution of the ‘one-line’ model for shoreline change. The former scheme, although fast and simple, is prone to instability. The latter is unconditionally stable, but is slower, significantly more complicated to program, and its accuracy decreases with increasing time step. Here, a technique known as the “method of lines” is used to solve the ‘one-line’ model. The advantages of using this method include: (1) unconditionally stable solutions, (2) accuracy that does not depend on a user-specified computation time step, and (3) simple and flexible coding. By using the method of lines procedure described in this paper, one can readily generate an efficient and adaptable ‘one-line’ numerical model for use in integrated coastal management.