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The purpose of this paper is to propose a fractional order optimization method based on perturbation bound and gamma function of a DGM(r,1).

By analyzing and minimizing perturbation bound, the sub-optimal solution on fractional order interval is obtained through offline solving without iterative calculation. By this method, an optimized fractional order non-equidistant ROGM (OFONEROGM) is applied in fitting and prediction water quality parameters for a surface water pollution monitoring system.

This method can narrow fractional order interval in this work. In a surface water pollution monitoring system, the fitting and prediction performances of OFONEROGM are demonstrated comparing with integer order non-equidistant ROGM (IONEROGM).

A method of offline solving the sub-optimal solution on fractional order interval is proposed. It can narrow the optimized fractional order range of NEROGM without iterative calculation. A large number of calculations are eliminated. Besides that, optimized fractional order interval is only related to the number of original data, and convenient for practical application. In this work, an OFONEROGM is modeled for predicting water quality trend for preventing water pollution or stealing sewage discharge. It will provide guiding significance in water quality parameter fitting and predicting for water environment management.

The purpose of this paper is to examine information-seeking behavior (ISB) of strategic planners in enterprise across different work-task types and stages.

A case study was conducted in a pharmaceutical company in China, labeled as T Company. One of the authors worked in the department of strategic planning of this company as an intern. The data were collected via participant observation and unstructured in-depth interviews. Open coding was performed to analyze the data.

Four work-task stages were identified: project preparation, gathering, discovery and presentation, and strategy formulation. The results indicate that work-task types, work-task stages, and strategic planners’ work role or position affect their information needs, source selection, and seeking process. Task complexity, task familiarity, and task goal are of the most important task attributes that directly shape strategic planners’ ISB. Work role determines the extent to which strategic planners can access the information of the company. Internal information has priority, but external information is also important when internal information is not sufficient; both are equally important for strategic planning projects. Social media has been a very important channel to access, disseminate and share information. Workshops are an important approach to producing final project reports. Face-to-face discussion and information exchange play a critical role in the formulation of new strategies.

This is a case study with data collected from only one company in China. Some of the results may not be generalizable. However, it adds new knowledge to ISB research in enterprise, informs people how to provide better information services for strategic planners, and informs MBA education for students’ better information-seeking skills.

Though myriad studies on ISB, little research has been done to examine strategic planners’ ISB from a business context, especially taking into account the effect of work-task types and stages.

The purpose of this paper is to establish a maturity evaluation model for the application of construction steel structure welding robotics suitable for the actual situation and specific characteristics of engineering projects in China and then to assess the maturity level of the technology in the application of domestic engineering projects more scientifically.

The research follows a qualitative and quantitative analysis method. In the first stage, the structure of the maturity model is constructed and the evaluation index system is designed by using the ideas of the capability maturity model and WSR methodology for reference. In the second stage, the design of the evaluation process and the selection of evaluation methods (analytic hierarchy process method, multi-level gray comprehensive evaluation method). In the third stage, the data are collected and organized (preparation of questionnaires, distribution of questionnaires, questionnaire collection). In the fourth stage, the established maturity evaluation model is used to analyze the data.

The evaluation model established by using multi-level gray theory can effectively transform various complex indicators into an intuitive maturity level or score status. The conclusion shows that the application maturity of building steel structure welding robot technology in this project is at the development level as a whole. The maturity levels of “WuLi – ShiLi – RenLi” are respectively: development level, development level, between starting level and development level. Comparison of maturity evaluation values of five important factors (from high to low): environmental factors, technical factors, management factors, benefit factors, personnel and group factors.

In this paper, based on the existing research related to construction steel structure welding robot technology, a quantitative and holistic evaluation of the application of construction steel structure welding robot technology in domestic engineering projects is conducted for the first time from a project perspective by designing a maturity evaluation index system and establishing a maturity evaluation model. This research will help the project team to evaluate the application level (maturity) of the welding robot in the actual project, identify the shortcomings and defects of the application of this technology, then improve the weak links pertinently, and finally realize the gradual improvement of the overall application level of welding robot technology for building steel structure.

This study considers a Lagrange direct way of modal assurance criterion (MAC) values of an undamped system. The mentioned method for the sensitivity analysis of the MAC of a sliding machine working table is more close to the exact solution and time efficient. The paper aims to discuss these issues.

Using the Lagrange multipliers to compute the first and second-order sensitivity analysis of MAC values.

Because of the Lagrange multiplier without considering the number of design parameters, one only needs to perform the calculation once. Compared with the indirect way, the direct way is more effective when the number of design parameters is greater than one. This calculation procedure is simple and accurate, which can be popularized and used.

Engineering structure often requires only some structure design, and most of the sub-structure design variables are not related to each other. In this case, this way is better and more efficient. The direct way can be applied to the dynamic optimization design of large structures, the frequency and the mode sensitivity analysis in the process of model modification.

The sheathing panels of traditional light wood frame shear walls mainly use oriented strand board (OSB) panels, and the damage of the traditional walls is mainly caused by the tear failure at the bottom corner of the OSB panel. In order to improve the lateral performance of the traditional light wood frame shear wall, a new type of end narrow panels reinforced light wood frame shear wall is proposed.

The monotonic loading tests and finite element analysis of nine groups of walls, with different types of end narrow panel, types of fasteners used on the end narrow panels and the end narrow panels edge fastener spacing, are carried out. The effects of different characters on lateral performance of light wood frame shear walls are reported and discussed.

The failure modes of the wall reinforced by parallel strand bamboo narrow panels with 150 mm edge nails spacing are similar to the traditional wall. Conversely, the failure modes of other groups of walls reinforced by end narrow panels are the tears of the bottom narrow panel or the bottom beam. The end narrow panel reinforced light wood frame shear wall can make full use of the material property of sheathing panels. Compared with the lateral performance of traditional walls, the new-type end narrow panels reinforced walls have better lateral performance.

A new type of end narrow panels reinforced light wood frame shear wall is proposed, which can enhance the lateral performance of the traditional light wood frame shear wall. The new-type walls have advantages of convenient operation, manufacture cost saving and important value of engineering application.

This paper aims to provide a framework of the supervised hyperspectral classification, to study the traditional flowchart of hyperspectral image (HIS) analysis and processing. HSI technology has been proposed for many years, and the applications of this technology were promoted by technical advancements.

First, the properties and current situation of hyperspectral technology are summarized. Then, this paper introduces a series of common classification approaches. In addition, a comparison of different classification approaches on real hyperspectral data is conducted. Finally, this survey presents a discussion on the classification results and points out the classification development tendency.

The core of this survey is to review of the state of the art of the classification for hyperspectral images, to study the performance and efficiency of certain implementation measures and to point out the challenges still exist.

The study categorized the supervised classification for hyperspectral images, demonstrated the comparisons among these methods and pointed out the challenges that still exist.

The purpose of this paper is to study the effect of doping, annealing temperature and visible optical excitation on CuO-ZnO nanocomposites’ acetone sensing properties and introduce an attractive candidate for acetone detection at about room temperature.

ZnO nanoparticles doped with CuO were prepared by sol-gel method, and the structure and morphology were characterized via X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and Brunauer-Emmett-Teller. The photoelectric responses of CuO-ZnO nanocomposites to cetone under the irradiation of visible light were investigated at about 30°C. The photoelectric response mechanism was also discussed with the model of double Schottky.

The doping of CuO enhanced performance of ZnO nanoparticles in terms of the photoelectric responses and the gas response and selectivity to acetone of ZnO nanoparticles, in addition, decreasing the operating temperature to about 30ºC. The optimum performance was obtained by 4.17% CuO-ZnO nanocomposites. Even at the operating temperature, about 30ºC, the response to 1,000 ppm acetone was significantly increased to 579.24 under the visible light irradiation.

The sensor fabricated by 4.17% CuO-ZnO nanocomposites exhibited excellent acetone-sensing characteristics at about 30ºC. It is promising to be applied in low power and miniature acetone gas sensors.

In the present research, a new nanocomposite material of CuO-ZnO was prepared by Sol-gel method. The optimum gas sensing properties to acetone were obtained by 4.17% CuO-ZnO nanocomposites at about 30ºC operating temperature when it was irradiated by visible light with the wavelength more than 420 nm.

The purpose of this paper is to design a model-based bilateral teleoperation method to improve the feedback force and velocity/position tracking for robotic-assisted tasks (such as palpation, etc.) under constant and/or varying time delay with environment dynamic property. Time delay existing in bilateral teleoperation easily destabilizes the system. Proper control strategies are able to make the system stable, but at the cost of compromised performance. Model-based bilateral teleoperation is designed to achieve enhanced performance of this time-delayed system, but an accurate model is required.

Viscoelastic model has been used to describe the robot tool-soft tissue interaction behavior. Kevin-Boltzmann (K-B) model is selected to model the soft tissue behavior due to its good accuracy, transient and linearity properties among several viscoelastic models. In this work, the K-B model is designed at the master side to generate a virtual environment of remote robotic tool-soft tissue interaction. In order to obtain improved performance, a self perturbing recursive least square (SPRLS) algorithm is developed to on-line update the necessary parameters of the environment with varying dynamics.

With fast and optimal on-line estimation of primary parameters of the K-B model, the reflected force of the model-based bilateral teleoperation at the master side is improved as well as the position/velocity tracking performance. This model-based design in the bilateral teleoperation avoids the stability issue caused by time delay in the communication channel since the exchanged information become position/velocity and estimated parameters of the used model. Even facing with big and varying time delay, the system keeps stably and enhanced tracking performance. Besides, the fast convergence of the SPRLS algorithm helps to track the time-varying dynamic of the environment, which satisfies the surgical applications as the soft tissue properties usually are not static.

The originality of this work lies in that an enhanced perception of bilateral teleoperation structure under constant/varying time delay that benefits robotic assisted tele-palpation (time varying environment dynamic) tasks is developed. With SPRLS algorithm to on-line estimate the main parameters of environment, the feedback perception of system can be enhanced with stable velocity/position tracking. The superior velocity/position and force tracking performance of the developed method makes it possible for future robotic-assisted tasks with long-distance communication.

The aim of this paper is to examine the effect of organizational environment on engineering project cost management.

Taking China Railway Engineering Corporation 2nd Bureau (CREC 2nd Bureau for short) as an example, the authors conduct lots of semi‐structured interviews in its group corporation, company limited, two subsidiaries and two project departments, and finally collect textual data which include 30 paragraphs and more than 120,000 words. The authors then encode those interview data step by step for further analysis under the research paradigm of grounded theory.

Based on these encoded data, the paper builds concept, basic categories, main categories, which could be the factors affecting the engineering project cost management, the evidence chain and the complete story clue among these categories. Then finally constructs a theoretical framework called “3S” for short, which is comprised of the organizational structure supporting system, the control procedure supporting system and the social relation supporting system.

Because of the insufficient importance placed on engineering project cost management by academics and few theoretical papers, this paper provides a new method for exploring the engineering project cost management and a theoretical reference for further research.

In this paper, the authors discuss the action mechanism of organizational environment in the engineering project cost management and provide for Chinese construction enterprises more explicit guidance on their cost management practice.

There is little research on determinants of engineering project cost by Chinese scholars, which is mainly shown as normative research. There is no perfect theoretical framework on the determinants of engineering project cost management, which is not beneficial to the knowledge of engineering project cost management and is not comprehensive and in depth enough for academics and practitioners. This paper conducts a field study in CREC 2nd Bureau based on grounded theory. At last, “3S” theoretical framework is established. This paper is embodied in using reality as the accordance, scientifically carding and spreading the theory and translating the practical experience into theory, so that it is beneficial for the engineering project cost management.

Traction substations are an integral part of the railway infrastructure. In order to ensure that machinery and equipment is available and utilised at full capacity, intelligent maintenance methods should be implemented. The purpose of this paper is to focus on the development of lean maintenance strategies implemented on traction substations and offer the maintenance manager an alternative maintenance method to be utilised during optimisation initiatives.

The rail company under consideration has various improvement options, the maintenance supply chain is a priority. The existing maintenance process of 3 kV_DC traction substations is examined and all operations and activities directly and indirectly associated with maintenance are analysed with lean methodologies. The analysis of maintenance operations and activities reveals that some of these operations and activities are non-value-adding and, therefore, regarded as waste. These activities only prolong the maintenance process without adding value to the process. Alternative operations and activities are suggested and simulated.

The application of lean indicates that the maintenance process could be optimised to deliver on a more efficient process, which would improve the quality of maintenance by ensuring that maintenance is timeously carried out. Through reducing the downtime caused by maintenance, the availability of the system is preserved and the railway lines could be used to capacity.

The research is limited to 3 kV_DC traction substations and the associated maintenance process, as this was the area of opportunity for the company. The track and overhead traction equipment maintenance is not included.

The practical application of this research is in optimisation of the value chain for maintenance, specifically in the rail industry.

This research could be applied by maintenance managers to effectively implement if a run-to-failure (RTF) maintenance philosophy is being utilised. The research offers maintenance techniques within the RTF maintenance scope which reduces the maintenance cycle and equipment downtime.