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1 – 10 of 502Zhiqiang Zhou, Yong Fu and Wei Wu
The human-following task is a fundamental function in human–robot collaboration. It requires a robot to recognize and locate a target person, plan a path and avoid obstacles. To…
Abstract
Purpose
The human-following task is a fundamental function in human–robot collaboration. It requires a robot to recognize and locate a target person, plan a path and avoid obstacles. To enhance the applicability of the human-following task in various scenarios, it should not rely on a prior map. This paper aims to introduce a human-following method that meets these requirements.
Design/methodology/approach
For the identification and localization of the target person (ILTP), this paper proposes an approach that integrates data from a camera, a light detection and ranging (LiDAR) and a ultra-wideband (UWB) anchor. For path planning and obstacle avoidance, a modified timed-elastic-bands (TEB) algorithm is introduced.
Findings
Compared to the UWB-only method, where only UWB is used to locate the target person, the proposed ILTP method in this paper reduces the localization error by 41.82%. Experimental results demonstrate the effectiveness of the ILTP and the modified TEB method under various challenging conditions. Such as crowded environments, multiple obstacles, the target person being occluded and the target person moving out of the robot’s field of view. The complete experimental videos are available for viewing on https://youtu.be/ZKbrNE1sePM.
Originality/value
This paper offers a novel solution for human-following tasks. The proposed ILTP method can recognize the target person among multiple individuals, determine whether the target person is lost and publish the target person’s position at a frequency of 20 Hz. The modified TEB algorithm does not rely on a prior map. It can plan paths and avoid obstacles effectively.
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Yong Fu, Kun Chen, Li He and Hui Tan Wang
The purpose of this paper is to address two major challenges faced by robotic fish when operating in underwater environments: insufficient path planning capabilities and…
Abstract
Purpose
The purpose of this paper is to address two major challenges faced by robotic fish when operating in underwater environments: insufficient path planning capabilities and difficulties in avoiding dynamic obstacles. To achieve this, a method is proposed that combines the Improved Rapid Randomized Tree Star (IRRT*) with the dynamic window approach (DWA).
Design/methodology/approach
The RRT-connect algorithm is used to determine an initial feasible path quickly. The quality of sampling points is then improved by dividing the regions and selecting each region’s probability based on its fitness value. The fitness function and roulette wheel method are introduced for region selection. Subtarget points of the DWA algorithm are extracted from the IRRT* algorithm to achieve real-time dynamic path planning.
Findings
In various maps, the iteration count for the IRRT* algorithm decreased by 61%, 35% and 51% respectively, compared to the RRT* algorithm, whereas the iteration time was reduced by 75%, 34% and 57%, respectively. In addition, the IRRT*-DWA algorithm can successfully navigate through multiple dynamic obstacles, and the average time, path length, etc. do not change much when parameters change, and the stability is high.
Originality/value
A novel IRRT*-DWA algorithm is proposed, which, by refining the sampling strategy and updating sub-target points in real time, not only addresses the limitations of existing algorithms in terms of path planning efficiency in complex environments but also enhances their capability to avoid dynamic obstacles. Ultimately, experimental results indicate a high level of similarity between the actual and ideal paths.
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G. M. Han and X. Q. Deng
Color is the dominant element of visual communication design. For cities, color is one of their characteristics. Improving the overall style of a city through the control and…
Abstract
Color is the dominant element of visual communication design. For cities, color is one of their characteristics. Improving the overall style of a city through the control and planning of architectural color has been a hot issue in urban control and planning in recent years. Considering color pollution in urban planning, we analyze the important role of color in visual communication design from the perspective of the visual communication concept of media art. The current situation of residential building colors in Shanghai City is investigated. We determine the residents’ preferences and requirements related to architectural exterior color on the basis of a data analysis of color and material selection, color matching, composition, and others. This study changes the traditional architectural color design concept that centers on individuals and lacks overall control. Specifically, we construct a set of multi-scale color controlling and planning systems at the macro-, meso-, and micro-scales. We also guide and control the urban architectural color such that it is in accordance with the systematic color planning strategy. This method enables the systematic and holistic external color planning of urban residential buildings.
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Tian Yong Fu, Mark J. Holmes and Daniel F.S. Choi
The purpose of this paper is to analyze volatility transmission between the Japanese stock and foreign exchange markets.
Abstract
Purpose
The purpose of this paper is to analyze volatility transmission between the Japanese stock and foreign exchange markets.
Design/methodology/approach
In contrast to the existing literature, industry‐level stock data are applied to a trivariate Baba, Engle, Kraft and Kroner‐generalised autoregressive conditional heteroscedasticity (BEKK‐GARCH) model that also includes comparable US industrial stocks returns as a control variable.
Findings
Using daily data over the study period 1994‐2007, it was found that news shocks in the Japanese currency market account for volatility transmission in eight of the ten industrial sectors considered. Evidence was also found of significant asymmetric effects in five of these industries.
Research limitations/implications
While the BEKK‐GARCH model enables analysis of volatility transmission between the stock and foreign markets against a background of conditional correlation and asymmetries, the model requires the estimation of a large number of parameters, which can be problematic for a limited dataset.
Originality/value
The paper's findings have important implications for understanding international volatility transmission involving the stock and foreign exchange markets. This in turn can provide insight into investor behaviour.
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Łukasz Kryszak, Katarzyna Świerczyńska and Jakub Staniszewski
Total factor productivity (TFP) has become a prominent concept in agriculture economics and policy over the last three decades. The main aim of this paper is to obtain a detailed…
Abstract
Purpose
Total factor productivity (TFP) has become a prominent concept in agriculture economics and policy over the last three decades. The main aim of this paper is to obtain a detailed picture of the field via bibliometric analysis to identify research streams and future research agenda.
Design/methodology/approach
The data sample consists of 472 papers in several bibliometric exercises. Citation and collaboration structure analyses are employed to identify most important authors and journals and track the interconnections between main authors and institutions. Next, content analysis based on bibliographic coupling is conducted to identify main research streams in TFP.
Findings
Three research streams in agricultural TFP research were distinguished: TFP growth in developing countries in the context of policy reforms (1), TFP in the context of new challenges in agriculture (2) and finally, non-parametric TFP decomposition based on secondary data (3).
Originality/value
This research indicates agenda of future TFP research, in particular broadening the concept of TFP to the problems of policy, environment and technology in emerging countries. It provides description of the current state of the art in the agricultural TFP literature and can serve as a “guide” to the field.
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Abstract
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L.A.M. Huertas‐Quintero, P.P. Conway, D.M. Segura‐Velandia and A.A. West
The purpose of this paper is to propose a new software tool to support design for quality (DfQ) in the electronics manufacturing sector where quality and reliability are critical.
Abstract
Purpose
The purpose of this paper is to propose a new software tool to support design for quality (DfQ) in the electronics manufacturing sector where quality and reliability are critical.
Design/methodology/approach
An integrated modelling framework that enables complete and realistic representations of manufacturing systems is proposed. A software tool, developed based on this framework, offers two modules to support DfQ: simulation and root cause analysis. This paper focuses on the latter.
Findings
Integrated models enable tracing back effects to their root causes. Software tools based on these, kind of models can provide support in finding and eliminating the cause of a particular effect. This capability can be used to perform DfQ in an effective and accurate way.
Research limitations/implications
The approach proposed strongly depends on the quality models within the integrated modelling framework. The models currently available are little and simplified. Future work includes the enrichment of the software by developing and more quality models.
Practical implications
The adoption of the proposed approach in an industrial context requires formalised information to fulfil the data required by the integrated modelling framework.
Originality/value
The main contribution of the paper is the integrated modelling framework definition and its implementation in the form of a software tool. The adoption of this tool in printed circuit assembly companies can support the solution of real quality problems and consequently, help to optimise manufacturing systems in the domain.
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F. Hanna and Z.A. Hamid
This work concerns the electrodeposition of highly pure brushite (CaHPO4·2H2O) on titanium alloy substrates and the transformation of the brushite to hydroxyapatite (HAp) Ca10(PO4…
Abstract
This work concerns the electrodeposition of highly pure brushite (CaHPO4·2H2O) on titanium alloy substrates and the transformation of the brushite to hydroxyapatite (HAp) Ca10(PO4)6(OH)2 as a coating for orthopaedic implants. Thus, the electrodeposition of electrolyte containing calcium nitrate and ammonium hydrogen phosphate was carried out. The influences of the substrate surface treatment, the electroplating conditions (bath composition, current density, pH value and temperature) and the hydrothermal post treatment conditions on the deposition rate, the throwing power, the adhesion, the morphology and the structure of the coating were evaluated. High adhesion bond strength (around 23 mPa) was achieved on a rough clean substrate, which is slightly higher than plasma sprayed HAp coating on titanium alloy.
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Yenming Zhang and Suan Fong Foo
Balanced leadership is attracting increasing attention from academia and practitioners. In this rapidly changing world, maintaining balance while moving ahead is becoming a…
Abstract
Purpose
Balanced leadership is attracting increasing attention from academia and practitioners. In this rapidly changing world, maintaining balance while moving ahead is becoming a challenge for organizational leaders concerned with effective leadership. The traditional concept of balancing, theoretically, has been frequently re‐visited by researchers, while new concepts of balancing are being developed by researchers and practitioners, in order to effectively guide the practice in the real institutional settings. The purpose of this paper is to examine the classic Chinese perspectives from Wu Xing, I Ching and Tao Te Ching. Some western perspectives (e.g. Waters and Leithwood) on balanced leadership are also examined, to reach a hybrid model in an effort to decipher the meanings of balancing, and to address their applicability in modern organizational lives.
Design/methodology/approach
This paper provides analyses of the perspectives in the Chinese classics Wu Xing, I Ching and Tao Te Ching, and presents insights on the principles for organizational leaders to apply in dealing with changes.
Findings
There is a philosophical base for balanced leadership. It is becoming imperative for leaders to practice balanced leadership in the following aspects of organizational lives: Leaders' steady dispositions; Harmonious human relations; Categorization of the magnitudes of change for improvement; and a hybrid model integrating both eastern and western concepts of balanced leadership.
Research limitations/implications
This paper focuses on one domain of leadership – balancing in the interactions between the leaders and their people. It is relevant for those who have interest in, and are concerned for, the vertical, lateral relations, organizational development and improvement.
Originality/value
This paper reflects the researchers' deep insight into the Chinese classics, their expertise, and their empirical practices in organizational leadership. The paper will help those with similar interests in this area to better understand the implications of the Chinese perspectives.
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Sivakumar Sundararajan and Senthil Arasu Balasubramanian
This study examines the dynamic linkages between the Indian Nifty index futures traded on the offshore Singapore Exchange (SGX) and US stock indices (DJIA, NASDAQ and S&P 500…
Abstract
Purpose
This study examines the dynamic linkages between the Indian Nifty index futures traded on the offshore Singapore Exchange (SGX) and US stock indices (DJIA, NASDAQ and S&P 500) under the closure of the spot market for Nifty futures.
Design/methodology/approach
With high-frequency 5-min overlapping price data, the authors employ the Johansen cointegration test to investigate long-run relationships, the Granger causality test to assess short-run dynamics and the BEKK-GARCH model for volatility spillover investigation.
Findings
The empirical findings reveal that the SGX Nifty futures market is cointegrated with the US DJIA market. The US DJIA stock index strongly influences the price discovery of SGX Nifty futures and past innovations in the US markets strongly impact the current volatility of SGX Nifty futures.
Practical implications
Findings from this study have significant implications for market participants, particularly foreign investors and portfolio managers. These findings might be helpful for market participants to improve the prediction power of expected SGX Nifty futures price and volatility, especially under the closure of the spot market. Also, SGX market participants can take the significant role of the US market into account when formulating hedging and trading strategies with Indian Nifty futures. Besides, our findings have significant implications for policymakers in evaluating market stability.
Originality/value
This article adds to the very limited research on offshore or international stock index futures; it is the first study that empirically examines the international linkages of offshore SGX Nifty futures under the closure of its underlying spot market and also the driving force behind the linkages.
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