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Traditional algorithms require at least two complete vector observations to estimate orientation parameters. However, sensor faults and disturbances may cause some components of vector observations unavailable. This paper aims to propose algorithms to realize orientation estimation using vector observations with one or two components lost.

The fundamental of the proposed method is using norm equation and dot product equation to estimate the lost components, then, using an improved TRIAD to calculate attitude matrix. Specific algorithms for one and two lost components cases are constructed respectively, and the nonuniqueness of orientation estimation is analyzed from a geometric point of view. At last, experiments are performed to test the proposed algorithms.

The loss of components results in the loss of orientation information. The introduction of the norm equation and dot product equation can partially compensate for the loss of information. Experiment results and analysis show that the proposed algorithms can provide effective orientation estimation, and in vast majority of applications, the proposed algorithms can provide a unique solution in one lost component case and double solutions in two lost components case.

The proposed method addresses the problem of orientation estimation when one or two components of vector observations are unavailable. The introduction of the norm equation and dot product equation makes the calculation cost low, while the analyses from a geometric point of view makes the study of nonuniqueness more intuitive.

The magnetometer measurement update plays a key role in correcting yaw estimation in fusion algorithms, and hence, the yaw estimation is vulnerable to magnetic disturbances. The purpose of this study is to improve the ability of the fusion algorithm to deal with magnetic disturbances.

In this paper, an adaptive measurement equation based on vehicle status is derived, which can constrain the yaw estimation from drifting when vehicle is running straight. Using this new measurement, a Kalman filter-based fusion algorithm is constructed, and its performance is evaluated experimentally.

The experiments results demonstrate that the new measurement update works as an effective supplement to the magnetometer measurement update in the present of magnetic disturbances, and the proposed fusion algorithm has better yaw estimation accuracy than the conventional algorithm.

The paper proposes a new adaptive measurement equation for yaw estimation based on vehicle status. And, using this measurement, the fusion algorithm can not only reduce the weight of disturbed sensor measurement but also utilize the character of vehicle running to deal with magnetic disturbances. This strategy can also be used in other orientation estimation fields.

The sources of magnetic sensors errors are numerous, such as currents around, soft magnetic and hard magnetic materials and so on. The traditional methods mainly use explicit error models, and it is difficult to include all interference factors. This paper aims to present an implicit error model and studies its high-precision training method.

A multi-level extreme learning machine based on reverse tuning (MR-ELM) is presented to compensate for magnetic compass measurement errors by increasing the depth of the network. To ensure the real-time performance of the algorithm, the network structure is fixed to two ELM levels, and the maximum number of levels and neurons will not be continuously increased. The parameters of MR-ELM are further modified by reverse tuning to ensure network accuracy. Because the parameters of the network have been basically determined by least squares, the number of iterations is far less than that in the traditional BP neural network, and the real-time can still be guaranteed.

The results show that the training time of the MR-ELM is 19.65 s, which is about four times that of the fixed extreme learning algorithm, but training accuracy and generalization performance of the error model are better. The heading error is reduced from the pre-compensation ±2.5° to ±0.125°, and the root mean square error is 0.055°, which is about 0.46 times that of the fixed extreme learning algorithm.

MR-ELM is presented to compensate for magnetic compass measurement errors by increasing the depth of the network. In this case, the multi-level ELM network parameters are further modified by reverse tuning to ensure network accuracy. Because the parameters of the network have been basically determined by least squares, the number of iterations is far less than that in the traditional BP neural network, and the real-time training can still be guaranteed. The revised manuscript improved the ELM algorithm itself (referred to as MR-ELM) and bring new ideas to the peers in the magnetic compass error compensation field.

This study examines the relationship between fashion leadership, clothing deprivation and satisfaction of Hong Kong young consumers. A survey was carried out with 309 university students and 228 working young people in Hong Kong. Factor analysis with varimax rotation was used to group various attributes into different factors related to clothing deprivation and satisfaction. Hirschman and Adcock's (1978) measure was adopted to classify subjects into various fashion groups. ANOVA followed by Scheffe's procedure was applied to detect differences in clothing deprivation and satisfaction between different fashion groups. The implications of the findings to fashion retailers are discussed.

In recent years, Asian countries have experienced rising rates of premarital cohabitation, mirroring a similar trend that could be observed in many European countries several decades ago. As international differences in these trends are often attributed to institutional and societal differences, this study explores how China’s and Germany’s welfare and cultural regimes relate to national differences in the timing and prevalence of premarital cohabitation and direct marriage.

On the basis of two post-hoc harmonized surveys (pairfam for Germany; CFPS for China), descriptive analyses and logistic regressions were conducted. A higher standardization of partnership trajectories during the transition to adulthood was observed in China; this being probably related to China’s collectivist and Germany’s individualistic culture. While urban–rural differences prevail in China, and are attributable to China’s hukou system, East and West Germans differ considerably in this regard, a finding which can be traced back to regional differences in historical legacy. Discrepancies in economic modernization explain why the likelihood of experiencing these events differs for individuals in the Eastern and Western Chinese provinces.

Besides these differences, the two national contexts resemble each other in the prevalence of educational hypergamy, as well as in greater rates of cohabitation prior to first marriage, in contrast to direct marriage, seen among wealthier individuals and those with higher education. For the first time, the effects of cultural and institutional differences on the transition to adulthood were compared between a collectivistic vs. individualistic cultural regime and a productivist vs. corporatist conservative welfare regime, enabling researchers to draw conclusions about the link between cultural and welfare regime types and partnership patterns.

This paper aims to increase protection behavior of epoxy coating on aluminum alloys with plasma electrolitic oxidation (PEO) process as pretreatment and to investigate the corrosion properties of duplex coating system on aluminum alloy.

The study used micro structure study, electrochemical impedance spectroscopy (EIS) investigation, water uptake investigation and pull-off test.

This study was done to investigate the effect of urea as an additive, which alters the current density and time of process parameters in the protective performance of epoxy coating on the aluminum substrate. The protective behavior of double-layer coatings was examined using EIS in 3.5 per cent NaCl solution. In addition, the adhesion strength of double-layer coatings was evaluated using pull-off test, and the results demonstrated that the adhesion strength of sample with higher content of urea and current density is about two times that of sample without PEO preparation.

The protective properties and adhesion strength of epoxy coating can be increased with PEO pretreatment.

The aim of the paper is to shed light on the use of chitosans and chitooligosaccharides as biopreservatives in various foods animal. Foods of animal and aquatic origin (milk, meat, fish, eggs, sea foods, etc) become contaminated with a wide range of microorganisms (bacteria, molds and yeasts) during harvesting, transporting, processing, handling and storage operations. Due to the perishable nature of these foods, their preservation is of utmost importance. Though many synthetic chemicals are available, yet their use is quite restricted due to their hazardous effects on human health.

Within the domain of food industry, traditionally chitosan is used for biopreservation of foods, which is well known for its nutritional and medicinal properties in human nutrition. However, chitooligosaccharides also possess a number of nutraceutical and health promoting properties in addition to their preservative effect and shelf-life extension of foods. In this study, the comparative effects of both chitosan and chitooligosaccharides on preservation of foods of animal and aquatic origin have been summarized.

Though chitosan has been extensively studied in various foods, yet the use of chitooligosaccharides has been relatively less explored. Chitooligosaccharides are bioactive molecules generated from chitosan and have several advantages over the traditional use of chitosan both in food products and on human health. But unfortunately, little or no literature is available on the use of chitooligosaccharides for preservation of some of the foods of animal origin. Notable examples in this category include cheese, beef, pork, chicken, fish, sea foods, etc.

This paper focuses on the effects of chitosans and chitooligosaccharides on the processing and storage quality of foods of animal and aquatic origin, which offers a promising future for the development of functional foods.

Past decades have witnessed significant contributions to theories of the firm, innovation and economic growth from two closely related paradigms, namely, the Capabilities School and National Innovation Systems Approach. Unlike the neoclassical models of the firm and growth, these two paradigms place emphasis on the knowledge and learning process in understanding economic development. Despite being closer to reality in their treatment of economic issues than their neoclassical school counterpart, the two paradigms have not put human agency in the forefront of their analysis. This paper constructs a theory of national capabilities in the subjectivist perspective, which is then extended to understand firm and national capabilities and competitiveness. While this paper recognizes the influence of institutions on firms' decision making, unlike contemporary evolutionary literatures, the subjectivist perspective highlights the fact that all institutions are the coordinating effort of human actions which attempt to interpret external events or make sense out of social or economic interactions.

The purpose of this paper is to use nearly a century’s worth of gang research to inform us about modern terrorist groups, specifically the Islamic State of Iraq and Syria (ISIS).

A case study approach is employed, comparing and contrasting the competing theoretical frameworks of gangs and terrorist organisations to understand group structure, demographics, patterns of behaviour (e.g. territoriality, strategic, and instrumental violence), goals, and membership patterns of ISIS.

The qualitative differences of ISIS make them more comparable to street gangs than other terrorist groups.

ISIS, while being qualitatively different from other terrorist groups, actually has many similarities with street gangs allowing for the adaptation of effective gang prevention, intervention, and suppression strategies. This paper highlights how the expansive literature on street gangs is able to inform practical interventions to directly target ISIS and deradicalise potential recruits. By introducing a gang-terror nexus on the crime-terror continuum, this paper provides a useful perspective on the decentralised but dynamic nature of modern era insurgencies. This paper urges similar case studies of terrorist organisations to determine the extent to which they conform to street gang characteristics.

Terrorist groups are often compared to street gangs, yet it has not been until the last few years that gang researchers (Curry, 2011; Decker and Pyrooz, 2011, 2015a, b) have begun to compare and contrast these two deviant group archetypes. The goal of this paper is to use nearly a hundred years of gang research to better equip scholars and practitioners with a broader understanding of terrorism and insurgency in the era of globalisation by presenting a case study of ISIS using a street gang perspective.

The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number of countries. As an illustration, it provides an overview of the curriculum used in the initial preparation of school principals at Beijing Normal University.

The paper draws mainly on writing and research from China, Australia and the USA to explore principal preparation and training in China.

In addition to providing a rich description of principal preparation in China, the paper's main findings comprise seven key challenges that confront China as it endeavours to provide quality principal preparation. These challenges include China's diversity and uneven social, cultural and educational development; limited resources in some regions throughout China; the place and importance of study tours for principal preparation; the teaching approach used to train principals; the process used for assessing principal learning during their training programs; the limited transfer of learning from the classroom to the school environment; and the timing of training for principals.

Each of the challenges arising here raises important practical implications for developers of principal training programs.

The paper paints a picture of principal preparation in China and raises a number of issues and challenges with which it continues to grapple. Of note is that China is not alone in facing some of these ongoing concerns.