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The purpose of this paper is to develop an online smoothing zero-velocity-update (ZUPT) method that helps achieve smooth estimation of human foot motion for the ZUPT-aided inertial pedestrian navigation system.

The smoothing ZUPT is based on a Rauch–Tung–Striebel (RTS) smoother, using a six-state Kalman filter (KF) as the forward filter. The KF acts as an indirect filter, which allows the sensor measurement error and position error to be excluded from the error state vector, so as to reduce the modeling error and computational cost. A threshold-based strategy is exploited to verify the detected ZUPT periods, with the threshold parameter determined by a clustering algorithm. A quantitative index is proposed to give a smoothness estimate of the position data.

Experimental results show that the proposed method can improve the smoothness, robustness, efficiency and accuracy of pedestrian navigation.

Because of the chosen smoothing algorithm, a delay no longer than one gait cycle is introduced. Therefore, the proposed method is suitable for applications with soft real-time constraints.

The paper includes implications for the smooth estimation of most types of pedal locomotion that are achieved by legged motion, by using a sole foot-mounted commercial-grade inertial sensor.

This paper helps realize smooth transitions between swing and stance phases, helps enable continuous correction of navigation errors during the whole gait cycle, helps achieve robust detection of gait phases and, more importantly, requires lower computational cost.

This paper aims to analyze the sensitivity of different external factors to the returns of the precious metals of gold, silver, platinum and palladium. The goal is to find similarities and differences between the dependencies of every factor to each metal in a time-varying framework.

A brief co-integration test for the precious metals is conducted followed by a Kalman smoother approach to study the different sensitivities to the price changes of precious metals. A dynamic time warping (DTW) approach finally compares sensitivities for pairs of precious metals to a specific factor.

Results point to strong time-dependencies of the sensitivities, such as a declining relationship of gold to equity volatility. Consistent strong relationships are rare and can be identified for the consumer price index and the dollar. the DTW approach finds higher similarities between platinum and palladium compared to other pairs.

The similarities and differences of the precious metals can be used by investors and risk managers in portfolio construction processes and risk analyses.

The focus of the research is put on a broader context of precious metals with different external factors instead of focusing on a single factor, enabling a comparison of differences and similarities of the sensitivities. The analysis via a Kalman Rauch–Tung–Striebel smoother together with a DTW approach has not been conducted before in this way and is able to characterize the dependencies by a single number.

The purpose of this paper is to investigate the use of 802.11e MAC to resolve the transmission control protocol (TCP) unfairness.

The paper shows how a TCP sender may adapt its transmission rate using the number of hops and the standard deviation of recently measured round‐trip times to address the TCP unfairness.

Simulation results show that the proposed techniques provide even throughput by providing TCP fairness as the number of hops increases over a wireless mesh network (WMN).

Future work will examine the performance of TCP over routing protocols, which use different routing metrics. Other future work is scalability over WMNs. Since scalability is a problem with communication in multi‐hop, carrier sense multiple access (CSMA) will be compared with time division multiple access (TDMA) and a hybrid of TDMA and code division multiple access (CDMA) will be designed that works with TCP and other traffic. Finally, to further improve network performance and also increase network capacity of TCP for WMNs, the usage of multiple channels instead of only a single fixed channel will be exploited.

By allowing the tuning of the 802.11e MAC parameters that have previously been constant in 802.11 MAC, the paper proposes the usage of 802.11e MAC on a per class basis by collecting the TCP ACK into a single class and a novel congestion control method for TCP over a WMN. The key feature of the proposed TCP algorithm is the detection of congestion by measuring the fluctuation of RTT of the TCP ACK samples via the standard deviation, plus the combined the 802.11e AIFS and CW_min allowing the TCP ACK to be prioritised which allows the TCP ACKs will match the volume of the TCP data packets. While 802.11e MAC provides flexibility and flow/congestion control mechanism, the challenge is to take advantage of these features in 802.11e MAC.

With 802.11 MAC not having flexibility and flow/congestion control mechanisms implemented with TCP, these contribute to TCP unfairness with competing flows.

In this paper, the design of multiple channels to achieve the goal of a high‐performance medium access control (MAC) protocol is to be proposed to solve the problem of wasting bandwidth resources due to waiting for the backoff time.

In the MAC design of this paper, a control channel and a data channel are used to improve bandwidth utilization. When the control channel waits for the backoff time, the data channel may transfer data. As a result, bandwidth utilization can be improved. In order to have better bandwidth utilization in multiple channels, the authors also propose a bandwidth allocation strategy for control channels and data channels. According to the strategy, the control and data signals can be smoothly transmitted without blocking or waiting, thereby not wasting bandwidth resources. Finally, the authors propose multiple control sub‐channels and data sub‐channels to further reduce the backoff time penalty and make more communication pairs work in a transmission range to increase the throughput.

The paper solves the following problems bandwidth waste that results from waiting for the backoff time in the single channel model and bandwidth allocation strategy for the control and data sub‐channels in the multiple channel model to achieve throughput enhancement in mobile ad‐hoc networks.

The proposed method needs the support of multiple channels.

From the result, the bandwidth allocation ratio of the proposed method performs better than other various allocation ratios. In addition, the proposed method with the bandwidth allocation strategy and multiple data and control sub‐channels results in a better throughput than IEEE 802.11 DCF by 22.3 per cent.

The proposed method using multiple control and data sub‐channels can improve the throughput and reduce bandwidth waste over IEEE 802.11 DCF.

This paper aims to focus on addressing endogeneity using instrument-free methods. The authors discuss some extensions to well-known techniques.

This paper discusses some attractive methods to address endogeneity without the need for instruments. The methods are labeled are “harmless” in the sense that instruments are not needed and the distributional assumptions are kept to a minimum or they are replaced by more flexible semi-parametric assumptions.

Using a hospitality application, the authors provide evidence about the effectiveness of these techniques and provide directions for their implementation.

Finding valid instruments has always been a key challenge for researchers in the field. This paper discusses and introduces methods that free researchers from the need to find instruments.

The paper discusses techniques that are introduced from the first time in the tourism literature.

Since it has been regarded as an effective method to evaluate clothing pressure comfort with physiological and psychological techniques the purpose of this paper is to examine the effect on people s inhibition ability caused by the oppression from clothing on the body through event-related potentials (ERPs). A trial application of ERPs technology was made to evaluate clothing pressure comfort and investigate the relationship between some physical indexes of brain wave and clothing pressure. This research would also reveal the influence of clothing pressure on the thinking ability and mental activity of young women.

Stroop color-naming task was utilized to test the inhibition ability of participants. In the present research, some components of ERPs (e.g. N1, P2, N2 and N450) and behavioral indexes (RTs, and errors rates) were detected to verify the change of physiology and psychology caused by the pressure imposed by girdle on the body.

At behavioral level RTs were slower for the group under pressure rather than pressure-free group with no significant difference in errors rate between the two groups. Based on the early component statistics of ERPs the Stroop effects of both groups were similar. Besides there was no prominent difference in the latencies and amplitudes of N1, P2 and N2 components except the N450 components. The inhibition ability of young women who had worn girdle for 8 hours decreased causing them unable to make a timely response and thus affecting their attentiveness and executive ability.

This study would clarify that it is feasible to evaluate clothing pressure comfort with ERPs as a physiological technique, and enrich relative methods.

A semiparametric stochastic frontier model is proposed for panel data, incorporating several flexible features. First, a constant elasticity of substitution (CES) production frontier is considered without log-transformation to prevent induced non-negligible estimation bias. Second, the model flexibility is improved via semiparameterization, where the technology is an unknown function of a set of environment variables. The technology function accounts for latent heterogeneity across individual units, which can be freely correlated with inputs, environment variables, and/or inefficiency determinants. Furthermore, the technology function incorporates a single-index structure to circumvent the curse of dimensionality. Third, distributional assumptions are eschewed on both stochastic noise and inefficiency for model identification. Instead, only the conditional mean of the inefficiency is assumed, which depends on related determinants with a wide range of choice, via a positive parametric function. As a result, technical efficiency is constructed without relying on an assumed distribution on composite error. The model provides flexible structures on both the production frontier and inefficiency, thereby alleviating the risk of model misspecification in production and efficiency analysis. The estimator involves a series based nonlinear least squares estimation for the unknown parameters and a kernel based local estimation for the technology function. Promising finite-sample performance is demonstrated through simulations, and the model is applied to investigate productive efficiency among OECD countries from 1970–2019.

This paper aims to discuss key concerns surrounding the recent implementation of the Markets in Financial Instruments Directive (MIFID II). It focuses on the UK regime. The insights derived are envisaged to be helpful guides for participants and regulators in financial markets.

This paper used the legal-economics perspective. It relied on primary data from statutes and regulations and secondary data from the public domain to analyze the phenomenon. The analytical framework comprised the following sections: Introduction, MiFID I review, MiFID II scope, MiFID II key concerns and concluding remarks.

Only half of the EU Member States including the UK managed to transpose MiFID II within the 3rd January 2018 effective date. At this early stage of implementation, various teething problems were encountered. These pertained to costs and charges reporting, firm governance, product governance, transaction reporting, best execution and research. Owing to the sheer scale and complexity of MIFID II, most entities barely coped with their reporting obligations. Noting the situation, the Financial Conduct Authority assured firms taking all sufficient steps that they would be treated fairly.

The paper was not sufficiently empirical. However, the study benefited reasonably from triangulation of data and perspectives to provide good insights on the implementation effects of the complex and voluminous EU rules for governing financial markets with global implications.

Investors could gain from the enhanced transparency and best execution rules. Investment banks could gain from the emerging resilient, integrated and efficient financial markets. Regulators with better access to more and higher quality reporting could intervene more effectively when required.

This paper assembled and critically analyzed currently available research insights in these areas so as to provide useful guidance to those needing to work and comply with MiFID II rules and academics teaching financial services law.

There is growing empirical evidence that firm heterogeneity is technologically non-neutral. This chapter extends the Gandhi, Navarro, and Rivers (2020) proxy variable framework for structurally identifying production functions to a more general case when latent firm productivity is multi-dimensional, with both factor-neutral and (biased) factor-augmenting components. Unlike alternative methodologies, the proposed model can be identified under weaker data requirements, notably, without relying on the typically unavailable cross-sectional variation in input prices for instrumentation. When markets are perfectly competitive, point identification is achieved by leveraging the information contained in static optimality conditions, effectively adopting a system-of-equations approach. It is also shown how one can partially identify the non-neutral production technology in the traditional proxy variable framework when firms have market power.

An ancient management axiom holds that, “If it ain't measured, it ain't managed.” A more topical management axiom says, “The mission of business is to manage for increased shareholder value.” Putting ancient and topical together, we deduce that, “Unless wealth is measured, business is not performing its mission.” Many managers believe this. Therefore one might expect the measurement of wealth to be a routine exercise in business accounting. It is not.