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New information technologies such as IoT and big data analytics have reshaped the development of smart green products. These products exhibit two important features that are not seen in traditional products: environmental friendliness and data network effect. Based on these unique features, the authors investigate a firm's optimal selling strategy of smart green products from both the profitability and environmental perspectives.

The authors establish stylized models to consider the optimality of three selling strategies: (1) traditional strategy – only offering traditional products, (2) green strategy – only offering smart green products, and (3) hybrid strategy – offering both traditional and smart green products.

The authors’ analysis shows that in the absence of data network effect, there will always be a conflict between profit maximization and environmental protection. However, a strategy that benefits both the firm and the environment exists when data network effect is present. Interestingly, hybrid and traditional strategies can be win-win strategies, but the green strategy cannot. Also surprisingly, the green strategy may harm the environment more as smart products become greener.

This study examines the economic and environmental implications of selling smart green products, and contributes to existing literature on sustainable operations and green product design by incorporating the impact of both consumer environmental awareness and data network effect. The authors’ findings shed light on how to coordinate the profitability and environmental impact of selling smart green products in the era of big data and IoT.

Robot kinematic modeling needs to be based on clear physical concepts. The widely used Denavit–Hartenberg (D–H) convention requires the coordinate system to be established on an extension of the axis. This leads to non-trivial problems which this study seeks to address by developing an improved convention.

First, the problems associated with the traditional D–H convention are systematically analyzed. Then, pursuant of solving these problems, an enhanced Denavit–Hartenberg (ED–H) convention is proposed, and a procedure is delineated for establishing the coordinate frame and obtaining the associated parameters. The transformation equations are derived based on a homogeneous matrix. The characteristics of traditional D–H and ED–H with regard to kinematics and dynamics are comprehensively compared. Finally, an application of dynamics for lead-through programming and collision protection is undertaken to validate the proposed ED–H method. Simulations and experiments are carried out using the Tiansui-One cooperative robot platform with the aim of exploring the merits of the proposed convention.

The proposed convention is compatible with traditional methods and can solve the problems inherent in these methods. The main characteristic of ED–H is that the coordinate system is fixed on the joint, which is a general modeling method.

An enhanced D–H convention is proposed to establish a unified, intuitive and accurate link model that exhibits stronger adaptability than traditional D–H and can be used effectively in kinematic and dynamic modeling of mechanical arms.

For some special manipulators such as the ones work at the space station, nuclear or some other unmanned environments, the overload, collision, vibration, temperature change or release of the internal stress would affect the structural parameters. And thus the operation precision might constantly decrease in long-term use. In these unmanned environments, the unattended manipulators should calibrate itself when they execute high precision operations or proceed self-maintenances. The purpose of this paper is to propose an automatic visual assistant on-line calibration (AVOC) method based on multi-markers.

A camera fixed on the end of the manipulator is used to measure one to three identification points, which forms an unstable multi-sensor eye-in-hand system. A Gaussian motion method which combines the linear quadratic regulator control and extended Kalman filter together is proposed to make the manipulator track the planned trajectories when its inaccurate structural parameters form uncertain motion errors. And a Monte-Carlo method is proposed to form a high precision and stable signal acquisition when the visual system has measurement errors and intermittent signal feedback. An automatic sampling process is adopted to select the optimal measurement points basing on their variances.

Data analysis and experiment results prove the efficiency and feasibility of the method proposed in this paper. With this method, the positioning accuracy is largely promoted from about 2 mm to 0.04–0.05 mm.

Experiments were carried out successfully on a manipulator in a life sciences glove box that will work at the Chinese space station. It is a low cost and efficient manipulator calibration method. The whole autonomic calibration process takes less than 10 min and requires no human intervention. In addition, this method not only can be used in the calibration of other unmanned articulated manipulator that works in deep ocean, nuclear industry or space but also be useful for the maintenance work in modern factories owing a lot of industrial robots.

This paper aims to propose a novel robot kinematic calibration method based on the common perpendicular line (CPL) model to improve the absolute accuracy of industrial robots.

The deviation between the nominal and actual twists is considered the CPL transformation, which includes the rotation about the CPL and the translation along the CPL. By using the invariance of the reciprocal product of the two spatial lines, the previous deviation was analyzed in the neighbor space of the base frame origin. In this space, the line vector of the CPL contained only four independent parameters: two orientation elements and two moment elements. Thus, the CPL model has four independent parameters for the revolute joint and two parameters for the prismatic joint.

By simulations and experiment conducted on a SCARA robot and a 6-DOF PUMA robot, the effectiveness of the novel method for calibration of industrial robot is validated.

The CPL model avoided the normalization and orthogonalization in the iterative identification procedure. Therefore, identifying the CPL model was not only simpler but also more accurate than that of the traditional model. In addition, the results of the CPL transformation strictly conformed to the constraints of the twist.

The purpose of this paper is to explore a case study in Washington State, USA where traditional stories (“oral tradition”) are being used in a contemporary context. Traditional knowledge is a system of experiential knowledge acquired through the continual observation of and interaction with the environment. This form of knowledge is still held by many societies and can provide an important contribution in emergency management for natural hazards. Those holding traditional knowledge can assist in understanding the nature of local hazards, suggest appropriate risk reduction and response mechanisms, and even give options for recovery based on past experiences.

The paper first discusses the nature of traditional knowledge and how it can contribute to emergency management. It then goes on to investigate a particular case study where a traditional Native American story has been combined with contemporary methods of hazard mitigation to create an educational video for tsunami hazard.

Traditional knowledge can be used effectively to undertake hazard education and enhance response to warnings. The video, titled “Run to Higher Ground!”, is an example of this, and has been readily taken up by indigenous communities and the general population (both in the USA and internationally) as an educational tool.

The paper will be of value to those working within the emergency management sector, and is particularly useful for communities who need to respond to warnings.

To discuss the historical roots of contemporary geopolitical economy, this paper aims to explore the complex and influential analysis of Tilly's formation of European national states as a predominant type of territorial political organization in contemporary world. To do this, Tilly described different eras of dominant organization of warfare in relation to state organization: patrimonialism, brokerage, nationalization, specialization. In this paper, we explore the link between the organization of military power and trade policy. We are trying to answer the question, if it is possible to credibly state a connection between the trade policy types pursued by selected states in specific historical periods and Tilly’s eras of dominant form of organization of warfare. For this purpose, we developed a typology of trade policies of important states throughout the history, using the economic history research of leading experts in the field. Our conclusion is that such a connection – between trade policy and Tilly’s eras of organization of warfare – can be made and that this connection is solidly supported by economic history. Our analysis may be of value for any critical assessment of international trade relations in contemporary geopolitical economy – and of influential cosmopolitan interpretations of the liberal trade regime of 19th century or globalization in 20th century.

In China, a major grain producer, rice losses during harvest cannot be ignored. The purpose of this paper is to assess the extent of rice harvest losses in major grain-producing areas in China by a sampling survey, and to further analyze the main factors influencing rice harvest losses using an ordered multinomial logistic model.

In this study, data were collected using a multi-stage sampling method from ten major rice-producing provinces/regions in China. On this basis, five counties were selected from each of these provinces/regions. In the actual survey, house numbers were randomly selected, and then corresponding farmer households were visited by trained investigators.

The survey found that 56.22 percent of respondents believed that rice harvest losses were 4 percent or lower in China, though there were differences among the provinces. The proportion of family business income, planting scale, mechanization level, timely harvest, and operational meticulousness had negative effects on rice harvest losses. On the other hand, farmers’ experience of employment as migrant workers had a positive effect on rice harvest losses. In addition, bad weather and short handedness during harvest significantly increased rice harvest losses.

The meaning of rice harvest losses was defined based on previous research findings on the definition of grain harvest losses and the realities in China. The current rice harvest losses in different areas in China were analyzed based on sampling survey data from 957 farmers in ten provinces in China.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

Affordability and lifestyle choices in housing are critical to meet basic human needs for shelter, security and wellbeing. The meaning of a house for a particular group of people and what is ‘affordable’ for a particular community is the critical issue. Dhaka, the capital of Bangladesh, has greater population density and rate of expansion compared to almost any other mega cities of Asia. The historic core of the city known as old Dhaka is a combination of several traditional neighborhoods. Houses in these traditional neighborhoods are not only places to live, rather an integral unit of a social system, having a good mix of place of work and individual expression in living. They also show flexibility and adaptability (with more scope for personalization and individual life style choices) compared to the contemporary housing stock. One of the success factors in these traditional houses is the healthy mix of the income ranges to avoid a ghetto effect of low cost housing. The recent rapid urbanization has led to a discontinuity of the traditional housing form of old Dhaka, leading to a disintegration of the mix of lifestyle choices and affordability. Following popular market trends, they are often replaced by housing blocks in a higher density ignoring the need for a diverse mix. This paper studies the traditional housing of old Dhaka with two case study neighborhoods. Several elements of housing like the common price, materials and construction, space layout, scale, social space, facades, street interface, etc are selected for a qualitative study. Local residents interview, archival records, maps, Plans, figure-ground, aerial images are used to analyze, identify and demonstrate the elements that made them socio-culturally sustainable and affordable for the community. With the analysis, lessons from the traditional housing form that may contribute to the new housing in Dhaka are identified.