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Encrypting information with pre-agreed key is an effective method to ensure information security. With the increasing requirement for key rate, this paper investigates the problem of simultaneously generating a secret key (SK) and a private key (PK) over three legitimate terminals with a trusted helper via public discussion that a passive eavesdropper completely access to. The legitimate terminals and the helper observe the correlated source sequences from the outputs of discrete memoryless source (DMS). The legitimate terminals wish to generate an SK that is concealed from the eavesdropper, and two designated legitimate terminals want to generate a PK that needs to be additionally keep secret from the third legitimate terminal. Under this model, the SK-PK capacity region is fully characterized, and the source coding scheme is further provided to show that the region is achievable. The security performance of the generated keys is analyzed in terms of key leakage rate.

We present the second part of our work on communicating correlated sources over multiple access (MAC) and interference channels (IC). Specifically, we undertake a Shannon-theoretic study of the above scenarios and focus on characterizing sufficient conditions for lossless recoverability of the sources at the decoder(s). We enhance the fixed block-length (B-L) coding technique by incorporating the technique of inducing source correlation onto channel inputs, originally discovered by Cover, El Gamal and Salehi. In contrast to the first part, performance analysis of a joint source-channel decoder poses new challenges. We enhance the earlier developed suite of coding and analytical tools to overcome these challenges and derive (simplified) single-letter characterizations for a new set of sufficient conditions for both scenarios. For both the MAC and IC problems, the derived sufficient conditions are (i) subsumed in the current known tightest, and (ii) strictly weaker for identified examples. Lastly, we propose simple ‘plug-in’ approaches that can further weaken the derived sufficient conditions. Our findings enable us to subsume Dueck’s findings (1981) and go even further for the example considered therein. [ABSTRACT FROM AUTHOR]

Consider a random access communication scenario over a channel whose operation is defined for any number of possible transmitters. As in the model recently introduced by Polyanskiy for the Multiple Access Channel (MAC) with a fixed, known number of transmitters, the channel is assumed to be invariant to permutations on its inputs, and all active transmitters employ identical encoders. Unlike the Polyanskiy model, in the proposed scenario, neither the transmitters nor the receiver knows which transmitters are active. We refer to this agnostic communication setup as the Random Access Channel (RAC). Scheduled feedback of a finite number of bits is used to synchronize the transmitters. The decoder is tasked with determining from the channel output the number of active transmitters, $k$ , and their messages but not which transmitter sent which message. The decoding procedure occurs at a time ${n}_{t}$ depending on the decoder’s estimate, $t$ , of the number of active transmitters, $k$ , thereby achieving a rate that varies with the number of active transmitters. Single-bit feedback at each time ${n}_{i}, {i} \leq {t}$ , enables all transmitters to determine the end of one coding epoch and the start of the next. The central result of this work demonstrates the achievability on a RAC of performance that is first-order optimal for the MAC in operation during each coding epoch. While prior multiple access schemes for a fixed number of transmitters require $2^{k} - 1$ simultaneous threshold rules, the proposed scheme uses a single threshold rule and achieves the same dispersion. [ABSTRACT FROM AUTHOR]

We consider the two scenarios of communicating a pair $S_{1},S_{2}$ of distributed correlated sources over 2–user multiple access (MAC) and interference channels (IC), respectively. While in the MAC problem, the receiver needs to reconstruct both sources, in the IC problem, receiver $j$ needs to reconstruct $S_{j}$. We undertake a Shannon theoretic study and focus on characterizing sufficient conditions. Building on Dueck’s findings (1981), we propose a coding scheme based on fixed block-length (B-L) codes. We characterize its information theoretic performance and characterize a new set of sufficient conditions. We identify examples of the MAC and IC problems for which the latter conditions are proven to be strictly weaker than the current known tightest. [ABSTRACT FROM AUTHOR]

The Gauss–Markov source produces $U_{i} = aU_{i-1} + Z_{i}$ for $i\geq 1$ , where $U_{0} = 0$ , $|a|< 1$ and $Z_{i}\sim \mathcal {N}(0, \sigma ^{2})$ are i.i.d. Gaussian random variables. We consider lossy compression of a block of $n$ samples of the Gauss–Markov source under squared error distortion. We obtain the Gaussian approximation for the Gauss–Markov source with excess-distortion criterion for any distortion $d>0$ , and we show that the dispersion has a reverse waterfilling representation. This is the first finite blocklength result for lossy compression of sources with memory. We prove that the finite blocklength rate-distortion function $R(n,d,\epsilon)$ approaches the rate-distortion function $\mathbb {R}(d)$ as $R(n,d,\epsilon) = \mathbb {R}(d) + \sqrt {\frac {V(d)}{n}}Q^{-1}(\epsilon) + o\left ({\frac {1}{\sqrt {n}}}\right)$ , where $V(d)$ is the dispersion, $\epsilon \in (0,1)$ is the excess-distortion probability, and $Q^{-1}$ is the inverse $Q$ -function. We give a reverse waterfilling integral representation for the dispersion $V(d)$ , which parallels that of the rate-distortion functions for Gaussian processes. Remarkably, for all $0 < d\leq \frac {\sigma ^{2}}{(1+|a|)^{2}}$ , $R(n,d,\epsilon)$ of the Gauss–Markov source coincides with that of $Z_{i}$ , the i.i.d. Gaussian noise driving the process, up to the second-order term. Among novel technical tools developed in this paper is a sharp approximation of the eigenvalues of the covariance matrix of $n$ samples of the Gauss–Markov source, and a construction of a typical set using the maximum likelihood estimate of the parameter $a$ based on $n$ observations. [ABSTRACT FROM AUTHOR]

The problem of network function computation over a directed acyclic network is investigated in this paper. In such a network, a sink node desires to compute with zero error a target function, of which the inputs are generated at multiple source nodes. The edges in the network are assumed to be error-free and have limited capacity. The nodes in the network are assumed to have unbounded computing capability and be able to perform network coding. The computing rate of a network code that can compute the target function over the network is the average number of times that the target function is computed with zero error for one use of the network. In this paper, we obtain an improved upper bound on the computing capacity, which is applicable to arbitrary target functions and arbitrary network topologies. This improved upper bound not only is an enhancement of the previous upper bounds but also is the first tight upper bound on the computing capacity for computing an arithmetic sum over a certain non-tree network, which has been widely studied in the literature. We also introduce a multi-dimensional array approach that facilitates evaluation of the improved upper bound. Furthermore, we apply this bound to the problem of computing a vector-linear function over a network. With this bound, we are not only able to enhance a previous result on computing a vector-linear function over a network but also simplify the proof significantly. Finally, we prove that for computing the binary maximum function over the reverse butterfly network, our improved upper bound is not achievable. This result establishes that in general our improved upper bound is non-achievable, but whether it is asymptotically achievable or not remains open. [ABSTRACT FROM AUTHOR]

In this paper, we prove a unified achievability bound that generalizes and improves random coding bounds for any combination of source coding, channel coding, joint source–channel coding, and coding for computing problems assuming blockwise node operation. As a general network setup, we consider an acyclic discrete memoryless network, where the network demands and constraints are specified by a joint-typicality constraint on the whole channel input and output sequences. For achievability, a basic building block for node operation consists of simultaneous nonunique decoding, simultaneous compression, and symbol-by-symbol mapping. Our bound can be useful for deriving random coding bounds without error analysis, especially for large and complex networks. In particular, our bound can be used for unifying and generalizing many known relaying strategies. For example, a generalized decode-compress-amplify-and-forward bound is obtained as a simple corollary of our main theorem, and it is shown to strictly outperform the previously known relaying schemes. Furthermore, by exploiting the symmetry in our bound, we formally define and characterize three types of network duality based on channel input–output reversal and network flow reversal combined with packing–covering duality. [ABSTRACT FROM AUTHOR]

It is well-known that the invocation of ‘equilibrium processes’ in thermodynamics is oxymoronic. However, their prevalence and utility, particularly in elementary accounts, presents a problem. We consider a way in which their role can be played by sets of sequences of processes demarcated by curves carrying the property of accessibility. We also examine the vexed question of whether equilibrium processes are necessarily reversible and the revision of this property in relation to sets of sequences of such processes. [ABSTRACT FROM AUTHOR]

Background: The past decade has seen substantial global reduction in malaria morbidity and mortality due to increased international funding and decisive steps by the international malaria community to fight malaria. South Africa has been declared ready to institute malaria elimination. However, research on the factors that would affect this policy implementation is inadequate. Objective: To investigate the stakeholders’ understanding of the malaria elimination policy in South Africa, including their perceived barriers and facilitators to effective policy implementation. Methods: The study followed a constructivist epistemological approach which manifests in phenomenological study design. Twelve purposively selected key informants from malaria researchers, provincial and national malaria programmes were interviewed using semi-structured interviews. Interview questions elicited interviewees’ knowledge of the policy and its achievability, including any perceived barriers and facilitating factors to effective implementation. The hybrid approach was used to perform thematic data analysis. Results: The dominant view was that malaria remains a problem in South Africa, exacerbated by staff attitudes and poor capacity, lack of resources, lack of new effective intervention tools, lack of intra- and inter-departmental collaboration, poor cross-border collaboration and weak stakeholder collaboration. Informants were concerned about the target year (2018) for elimination, and about the process followed in developing the policy, including the perceived malaria epidemiology shortfalls, regulatory issues and political context of the policy. Conclusions: Achievability of malaria elimination remains a subject of intense debate for a variety of reasons. These include the sporadic nature of malaria resurgence, raising questions about the contributions of malaria control interventions and climate to the transmission trends in South Africa. The shortage of resources, inadequate staff capacity, lack of any new effective intervention tools, and gaps in malaria epidemiology were key concerns, as was the superficially participative nature of the consultation process followed in developing the policy.

In this paper, we develop achievability schemes for symmetric $K$ -user interference channels with a rate-limited feedback from each receiver to the corresponding transmitter. We study this problem under two different channel models: the linear deterministic model, and the Gaussian model. For the deterministic model, the proposed scheme achieves a symmetric rate that is the minimum of the symmetric capacity with infinite feedback, and the sum of the symmetric capacity without feedback and the symmetric amount of feedback. For the Gaussian interference channel, we use lattice codes to propose a transmission strategy that incorporates the techniques of Han–Kobayashi message splitting, interference decoding, and decode and forward. This strategy achieves a symmetric rate, which is within a constant number of bits to the minimum of the symmetric capacity with infinite feedback, and the sum of the symmetric capacity without feedback and the amount of symmetric feedback. This constant is obtained as a function of the number of users, $K$ . We note that for the special case of Gaussian IC with $K = 2$ , our proposed achievability scheme results in a symmetric rate that is within at most 21.085 bits/s/Hz of the outer bound, which is the first constant gap bound despite the constant gap claim in [1]. The symmetric achievable rate is used to characterize the achievable generalized degrees of freedom, which exhibits a gradual increase from no feedback to perfect feedback in the presence of feedback links with limited capacity. [ABSTRACT FROM PUBLISHER]

This paper shows new general nonasymptotic achievability and converse bounds and performs their dispersion analysis for the lossy compression problem in which the compressor observes the source through a noisy channel. While this problem is asymptotically equivalent to a noiseless lossy source coding problem with a modified distortion function, nonasymptotically there is a noticeable gap in how fast their minimum achievable coding rates approach the common rate-distortion function, as evidenced both by the refined asymptotic analysis (dispersion) and the numerical results. The size of the gap between the dispersions of the noisy problem and the asymptotically equivalent noiseless problem depends on the stochastic variability of the channel through which the compressor observes the source. [ABSTRACT FROM PUBLISHER]

The Gupta-Kumar's nearest-neighbor multihop routing with/without infrastructure support achieves the optimal capacity scaling in a large erasure network in which n wireless nodes and m relay stations are regularly placed. In this paper, a capacity scaling law is completely characterized for an infrastructure-supported erasure network where n wireless nodes are randomly distributed, which is a more feasible scenario. We use two fundamental path-loss attenuation models (i.e., exponential and polynomial power-laws) to suitably model an erasure probability. To show our achievability result, the multihop routing via percolation highway is used and the corresponding lower bounds on the total capacity scaling are derived. Cut-set upper bounds on the capacity scaling are also derived. Our result indicates that, under the random erasure network model with infrastructure support, the achievable scheme based on the percolation highway routing is order-optimal within a polylogarithmic factor of n for all values of m. [ABSTRACT FROM AUTHOR]

We consider an energy harvesting point-to-point communication system where the transmitter is powered by an energy arrival process and is equipped with a battery of finite capacity B\max, which could be used for saving energy for future use. We assume a discrete i.i.d. energy arrival process where at each time step, energy of amount A_i is harvested with probability p_i \forall i \in \1, 2, \ldots, K\ independent of the other time steps. We provide upper and lower bounds on the capacity of this channel. These bounds are shown to be within a constant gap for K\le 3 for all parameters, and for $K > 3$ when the battery capacity B\max is small or large enough, where this constant does not depend on any energy or battery parameters. [ABSTRACT FROM PUBLISHER]

Background: Although the UK fit note has been broadly welcomed as a tool to facilitate return to work, difficulties and uncertainties have resulted in wide variation in its use. Agreement on what constitutes the 'ideal' fit note from the perspective of all stakeholders is needed to inform best practice. A recent Delphi study conducted by the authors reached consensus on 67 recommendations for best practice in fit note use for employed patients. However, such recommendations are not necessarily followed in practice. The purpose of this study was therefore to investigate the perceived achievability of implementing these Delphi recommendations with a further reference panel of stakeholders. Methods: Potential participants were identified by the research team and study steering group. These included representatives of employers, government departments, trades unions, patient organisations, general and medical practitioners and occupational health organisations who were believed to have the knowledge and experience to comment on the recommendations. The consensus Delphi statements were presented to the participants on-line. Participants were invited to comment on whether the recommendations were achievable, and what might hinder or facilitate their use in practice. Free text comments were combined with comments made in the Delphi study that referred to issues of feasibility or practicality. These were synthesised and analysed thematically. Results: Twelve individuals representing a range of stakeholder groups participated. Many of the recommendations were considered achievable, such as improved format and use of the electronic fit note, completion of all fields, better application and revision of guidance and education in fit note use. However a number of obstacles to implementation were identified. These included: legislation governing the fit note and GP contracts; the costs and complexity of IT systems and software; the limitations of the GP consultation; unclear roles and responsibilities for the funding and delivery of education, guidance and training for all stakeholders, and the evaluation of practice. Conclusions: This study demonstrated that although many recommendations for the ideal fit note are considered achievable, there are considerable financial, legal, organisational and professional obstacles to be overcome in order for the recommendations to be implemented successfully. [ABSTRACT FROM AUTHOR]

In network communications, information trans-mission often encounters wiretapping attacks. Secure network coding is introduced to prevent information from being leaked to adversaries. The investigation of performance bounds on the numbers of source symbols and random symbols are two fundamental research problems. For an important case that each wiretap-set with cardinality not larger than $r$, Cai and Yeung proposed a coding scheme, which is optimal in the senses of maximizing the number of source symbols and at the same time minimizing the number of random symbols. In this letter, we further study achievable lower bound on the number of random key and show that it just depends on the security constraint, and particularly, is independent to the information amount for transmission. This implies that when the number of transmitted source message changes, we can't reduce the number of random key to keep the same security level. We further give an intuitive interpretation on our result. In addition, a similar construction of secure linear network codes is proposed, which achieves this lower bound on the number of random key no matter how much information is transmitted. At last, we also extend our result to imperfect security case. [ABSTRACT FROM PUBLISHER]

In this two-part paper, information-theoretic capacity scaling laws are analyzed in an underwater acoustic network with n regularly located nodes on a square, in which both bandwidth and received signal power can be limited significantly. Parts I and II deal with an extended network of unit node density and a dense network of unit area, respectively. In both cases, a narrow-band model is assumed where the carrier frequency is allowed to scale as a function of n, which is shown to be crucial for achieving the order optimality in multi-hop (MH) mechanisms. We first characterize an attenuation parameter that depends on the frequency scaling as well as the transmission distance. Upper and lower bounds on the capacity scaling are then derived. In Part I, we show that the upper bound on capacity for extended networks is inversely proportional to the attenuation parameter, thus resulting in a highly power-limited network. Interestingly, it is shown that the upper bound is intrinsically related to the attenuation parameter but not the spreading factor. Furthermore, we propose an achievable communication scheme based on the nearest-neighbor MH transmission, which is suitable due to the low propagation speed of acoustic channel, and show that it is order-optimal for all operating regimes of extended networks. Finally, these scaling results are extended to the case of random node deployments providing fundamental limits to more complex scenarios of extended underwater networks. [ABSTRACT FROM AUTHOR]

This is the second in a two-part series of papers on information-theoretic capacity scaling laws for an underwater acoustic network. Part II focuses on a dense network scenario, where nodes are deployed in a unit area. By deriving a cut-set upper bound on the capacity scaling, we first show that there exists either a bandwidth or power limitation, or both, according to the operating regimes (i.e., path-loss attenuation regimes), thus yielding the upper bound that follows three fundamentally different information transfer arguments. In addition, an achievability result based on the multi-hop (MH) transmission is presented for dense networks. MH is shown to guarantee the order optimality under certain operating regimes. More specifically, it turns out that scaling the carrier frequency faster than or as $$n^{1/4}$$ is instrumental towards achieving the order optimality of the MH protocol. [ABSTRACT FROM AUTHOR]

Background: Maternal mortality is high the world over, especially in sub-Saharan Africa, including Nigeria. Nigeria has consistently demonstrated one of the most abysmally poor reproductive health indices in the world, maternal mortality inclusive. This is a sad reminder that, unless things are better organized, Southeast Nigeria, which Nnamdi Azikiwe University Teaching Hospital (NAUTH) represents, may not join other parts of the world in attaining Millennium Development Goal 5 to improve maternal health in 2015. Objectives: This study was conducted to assess NAUTH'S progress in achieving a 75% reduction in the maternal mortality ratio (MMR) and to identify the major causes of maternal mortality. Materials and methods: This was a 10-year retrospective study, conducted between January 1, 2003 and December 31, 2012 at Nnamdi Azikiwe University Teaching Hospital, Nnewi, Southeast Nigeria. Results: During the study period, there were 8,022 live births and 103 maternal deaths, giving an MMR of 1,284/100,000 live births. The MMR was 1,709 in 2003, reducing to 1,115 in 2012. This is to say that there was a 24.86% reduction over 10 years, hence, in 15 years, the reduction should be 37%. This extrapolated reduction over 15 years is about 38% less than the target of 75% reduction. The major direct causes of maternal mortality in this study were: pre-eclampsia/eclampsia (27%), hemorrhage (22%), and sepsis (12%). The indirect causes were: anemia, anesthesia, and HIV encephalopathy. Most of the maternal deaths occurred in unbooked patients (98%) and within the first 48 hours of admission (76%). Conclusion: MMRs in NAUTH are still very high and the rate of reduction is very slow. At this rate, it will take this health facility 30 years, instead of 15 years, to achieve a 75% reduction in maternal mortality. [ABSTRACT FROM AUTHOR]

This paper finds new tight finite-blocklength bounds for the best achievable lossy joint source-channel code rate, and demonstrates that joint source-channel code design brings considerable performance advantage over a separate one in the nonasymptotic regime. A joint source-channel code maps a block of k source symbols onto a length-n channel codeword, and the fidelity of reproduction at the receiver end is measured by the probability \epsilon that the distortion exceeds a given threshold d. For memoryless sources and channels, it is demonstrated that the parameters of the best joint source-channel code must satisfy nC - kR(d) \approx \sqrt nV + k \cal V(d) Q^-1\left(\epsilon \right), where C and V are the channel capacity and channel dispersion, respectively; R(d) and \cal V(d) are the source rate-distortion and rate-dispersion functions; and Q is the standard Gaussian complementary cumulative distribution function. Symbol-by-symbol (uncoded) transmission is known to achieve the Shannon limit when the source and channel satisfy a certain probabilistic matching condition. In this paper, we show that even when this condition is not satisfied, symbol-by-symbol transmission is, in some cases, the best known strategy in the nonasymptotic regime. [ABSTRACT FROM PUBLISHER]

A capacity scaling law is studied for a hybrid erasure network where a number of wireless nodes and infrastructure nodes, or equivalently base stations, exist. A polynomial decay model is used to suitably characterize an erasure probability for transmission between nodes. Based on the model, upper and lower bounds on the total capacity scaling are derived. Our result indicates that the two bounds are of exactly the same order under a certain condition on the decay parameter for the hybrid erasure network. [ABSTRACT FROM PUBLISHER]

This paper studies the minimum achievable source coding rate as a function of blocklength n and probability \epsilon that the distortion exceeds a given level d. Tight general achievability and converse bounds are derived that hold at arbitrary fixed blocklength. For stationary memoryless sources with separable distortion, the minimum rate achievable is shown to be closely approximated by R(d) + \sqrt V(d) \over n Q^-1\left(\epsilon \right), where R(d) is the rate-distortion function, V(d) is the rate dispersion, a characteristic of the source which measures its stochastic variability, and Q^-1\left(\cdot \right) is the inverse of the standard Gaussian complementary cumulative distribution function. [ABSTRACT FROM PUBLISHER]

Abstract: Given a plant and a desired specification our goal is to construct a controller system which, when interconnected with the plant, yields a system that behaves like the desired specification. We can always construct the canonical controller introduced in van der Schaft (2003) . For linear systems there exists a controller which when interconnected to the plant yields the desired behaviour if and only if the canonical controller is itself one such controller, see Vinjamoor and van der Schaft (2011) . In this paper we extend this result to nonlinear systems. It turns out that one has to look at the canonical controller together with its subsystems. We obtain necessary and sufficient conditions for the existence of a controller for a class of nonlinear systems. We end with examples which show that in certain cases looking at subsystems of the canonical controller also does not suffice. [Copyright &y& Elsevier]

This paper addresses the problematic issue of teaching English pronunciation to Japanese learners, advocating a shift away from the native speaker as a model. An argument is presented for the development and recognition of a distinct Japanese English pronunciation standard that can be used as a guideline to inform oral English teaching practices in the Japanese school system. Suggestions are made at the end of the paper for future research to contribute towards the development of such guidelines. [ABSTRACT FROM AUTHOR]

This paper investigates the maximal channel coding rate achievable at a given blocklength and error probability. For general classes of channels new achievability and converse bounds are given, which are tighter than existing bounds for wide ranges of parameters of interest, and lead to tight approximations of the maximal achievable rate for blocklengths n as short as 100. It is also shown analytically that the maximal rate achievable with error probability V is closely approximated by C - √V/n Q-1(ε) where C is the capacity, ε is a characteristic of the channel referred to as channel dispersion, and Q is the complementary Gaussian cumulative distribution function. [ABSTRACT FROM AUTHOR]

This paper introduces a formalism for modeling interaction and control of partially observed discrete event systems (DESs), called prioritized synchronous composition under mask (PSC/M). In PSC/M, each system is associated with an event priority set and an observation mask. The existing formalisms have their limitations and what we propose is a general canonical mode of interaction that is suitable for control under partial observation as well as for modeling a variety of interaction modes such as strict/prioritized synchronization, interleaving, hiding, and renaming. In PSC/M, an event is globally enabled if it is locally enabled by all the interacting systems. The tracking of a globally enabled event is done by executing a transition on an indistinguishable event. PSC/M possesses the useful properties of commutativity and associativity. PSC/M can be applied to compose local controller modules having limited sensing and actuation capabilities to obtain an equivalent global controller module. PSC/M can itself be employed as a control mechanism, in which case it helps remove the control and the observation compatibility requirements of a controller. We study the PSC/M-based control problem where both the plant and the supervisor have their own control and observation limitations. The plant and the specification models need not be at the same level of abstraction and so new classes of control problems can be solved in the framework. The existence condition is the achievability with respect to an augmented plant, which is weaker than controllability and observability combined. The weaker condition is required since we allow supervisors to be nondeterministic, which also facilitates the existence and synthesis to be performed polynomially in the size of the plant and the specification. Note to Practitioners—This paper presents a mechanism of composition for modeling the interaction of DESs. To form the composition one needs to identify for each system the events that it can control (actuator events) and the events that it can observe (sensor events). The composition ensures that a system never blocks its uncontrollable events and never reacts differently to events that are observationally indistinguishable. An event is executable in the composition if it is enabled by all participating systems and either trackable or executable in some participating system. An event is enabled by a participating system if it is either currently executable or a nonpriority event, whereas an event is trackable by a participating system if it is observable and indistinguishable to some currently executable event. A state update on an event, executable in the composition, occurs by executing an indistinguishable event by each participating system in which the event is trackable, whereas the other participating systems retain their current states. The composition is commutative and associative, supporting incrementality. We obtain a condition under which a given system (plant) can be controlled to exhibit the desired behaviors when the proposed mechanism is employed to compose the plant and a controller. The plant and the desired behavior models may differ in their levels of abstraction. The condition can be polynomially verified and a controller can be synthesized in linear complexity. [ABSTRACT FROM AUTHOR]

A hybrid system is constructed in this study for wafer-lot-output time prediction and achievability evaluation, which are critical tasks for a wafer fab (fabrication plant). In the first part of the hybrid system, a look-ahead self-organization map fuzzy-back-propagation network (SOM-FBPN) is constructed to predict the output time of a wafer lot. Compared with traditional approaches in this field, the look-ahead SOM-FBPN has three advanced features: incorporating the future release plan, classifying wafer lots, and incorporating expert opinions. According to experimental results, the prediction accuracy and efficiency of the look-ahead SOM-FBPN were significantly better than those of many existing approaches. In the second part of the hybrid system, a set of fuzzy inference rules (FIRs) are established to evaluate the achievability of an output time forecast, which is defined as the possibility that the fabrication on the wafer lot can be finished in time before the output time forecast. Achievability is as important as accuracy and efficiency but has been ignored in traditional studies. With the proposed methodology, both output time prediction and achievability evaluation can be concurrently accomplished. [ABSTRACT FROM AUTHOR]

It is proposed a synthesis method of designing an inductive position sensor with Tikhonov regularization procedure. Details about the mathematical modeling and numerical solutions obtained are discussed. [ABSTRACT FROM AUTHOR]

Background: The past decade has seen substantial global reduction in malaria morbidity and mortality due to increased international funding and decisive steps by the international malaria community to fight malaria. South Africa has been declared ready to institute malaria elimination. However, research on the factors that would affect this policy implementation is inadequate. Objective: To investigate the stakeholders’ understanding of the malaria elimination policy in South Africa, including their perceived barriers and facilitators to effective policy implementation. Methods: The study followed a constructivist epistemological approach which manifests in phenomenological study design. Twelve purposively selected key informants from malaria researchers, provincial and national malaria programmes were interviewed using semi-structured interviews. Interview questions elicited interviewees’ knowledge of the policy and its achievability, including any perceived barriers and facilitating factors to effective implementation. The hybrid approach was used to perform thematic data analysis. Results: The dominant view was that malaria remains a problem in South Africa, exacerbated by staff attitudes and poor capacity, lack of resources, lack of new effective intervention tools, lack of intra- and inter-departmental collaboration, poor cross-border collaboration and weak stakeholder collaboration. Informants were concerned about the target year (2018) for elimination, and about the process followed in developing the policy, including the perceived malaria epidemiology shortfalls, regulatory issues and political context of the policy. Conclusions: Achievability of malaria elimination remains a subject of intense debate for a variety of reasons. These include the sporadic nature of malaria resurgence, raising questions about the contributions of malaria control interventions and climate to the transmission trends in South Africa. The shortage of resources, inadequate staff capacity, lack of any new effective intervention tools, and gaps in malaria epidemiology were key concerns, as was the superficially participative nature of the consultation process followed in developing the policy. [ABSTRACT FROM PUBLISHER]