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Department Publication Year Content Type Data Sources

5421.Do Auditors Respond to Media Coverage? Evidence from China

Author:Gong, SX;Gul, FA;Shan, LW


Abstract:SYNOPSIS: This paper examines whether news coverage of client firms is associated with their audit fees. Using data from China listed firms during 2004-2013, we find that high coverage client firms are on average charged higher audit fees, irrespective of the media tone. This positive association is stronger for large auditors than for small auditors, and for bad news than for good news. The main results hold for both state-owned enterprises (SOEs) and non-SOEs, and for both politically connected and non-connected firms. The results are robust after controlling for the effects of information asymmetry, auditor choice, internal corporate governance, and alternative measurements of the key variables. Overall, our evidence is supportive of the view that auditors assess high coverage clients as higher risk audits requiring greater audit efforts. We conclude that the financial news media plays a disciplining role in China through its potential to trigger reputational sanctions and regulatory action.

5422.Hybrid-mode interleaved boost converter design for fuel cell electric vehicles

Author:Wen, HQ;Su, B


Abstract:For Fuel Cell Electric Vehicles, DC-DC power converters are essential to provide energy storage buffers between fuel cell stacks and the traction system because fuel cells show characteristics of low-voltage high-current output and wide output voltage variation. This paper presents a hybrid-mode two-phase interleaved boost converter for fuel cell electric vehicle application in order to improve the power density, minimize the input current ripple, and enhance the system efficiency. Two operation modes are adopted in the practical design: mode I and mode II are used with each boost converter operating in continuous conduction mode and discontinuous conduction mode. The operation, design and control of the interleaved boost converter for different operating modes are discussed with their equivalent circuits. The boundary conditions are distinguished with respect to switching duty ratio and load conditions. Transitions between continuous conduction mode and discontinuous conduction mode are illustrated for the whole duty ratio range. The expressions for inductor current ripple, input current ripple and output voltage ripple are derived and verified by simulation and experimental tests. The efficiency and power density improvements are illustrated to verify the effectiveness of the proposed design scheme. (C) 2016 Elsevier Ltd. All rights reserved.

5423.Dual-goal management in social enterprises: evidence from China

Author:Yin, JL;Chen, H


Abstract:Purpose Taking China as a research context, the purpose of this paper is to delineate how social and business tensions manifest in Chinese nascent social enterprises and to disentangle the strategies that they adopt to manage the business-social dual goals to achieve organizational viability. Design/methodology/approach A qualitative multiple-case study is used to collect and analyze data. Empirical data are drawn from in-depth semi-structured interviews with Chinese social entrepreneurs, ethnographic observation of social enterprises as well as secondary sources. Findings Depending on personal motivations and resource availability, social entrepreneurs' perceptions toward pursuit of dual goals range from integration to differentiation in the short term, despite consensus on the concurrent development in the long term. The leverage of resources, image management, continuous innovation and need-based services are viable approaches that Chinese social enterprises adopt to manage the dual goals in order to create both social and economic value. Research limitations/implications This paper reveals understanding of the concrete tensions experienced among Chinese nascent social enterprises in pursuing business and social goals and how they manage to integrate the synergistic aspects of social and business goals to achieve survival and growth. Based primarily on qualitative case study method, the research findings are context specific and may not be ideal for generalization. Practical implications The authors reveal strategies by which synergistic benefits between dual goals may be achieved. Innovation (e.g. in resource utilization, in service format and content) and differentiation (e.g. in organization positioning) would be beneficial in enhancing the competitiveness of social enterprises. To enhance organizations' credibility, quality of products and service should be monitored and organizational transparency needs to be enhanced. Social implications It is suggested that the government specifies legal forms and legitimates interests of social enterprises, formulates preferential policies to stimulate the development of social enterprises, and develops a set of qualification authentication system to regulate this emerging sector. Originality/value The study examines the manifestation of business and social tensions and presents dual-goal management strategies from a non-western perspective. As an original contribution to the field of social entrepreneurship, the study responds to calls for in-depth analysis of conflicting objectives and tension management in social enterprises.

5424.Bias-stress stability and radiation response of solution-processed AlOx dielectrics investigated by on-site measurements

Author:Fang, YX;Zhao, C;Mitrovic, IZ;Hall, S;Yang, L;Zhao, CZ


Abstract:In this work, the effects of biased irradiation on solution-processed and atomic layer deposited (ALD) AlOx thin films MOS capacitors were investigated by an on-site technique. The devices were irradiated by a 662-KeV Cs-137 gamma-ray radiation source under different positive/negative gate biases. The radiation time was up to 10(5) s and the total dose was around 92 Gy. It has been found that radiation could result in reversibility of flat-band voltage shifts (Delta V-FB)of solution-processed AlOx MOS capacitors, which were further analyzed through calculating the radiation induced oxide traps (Delta N-ot) in AlOx thin film and interface traps at AlOx/Si interface (Delta N-it). Additionally, solution-processed AlOx MOS capacitors exhibit more radiation induced charges compared to those fabricated by ALD, which indicates that solution-processed AlOx thin films contain abundant precursor impurities and bonded oxygen.

5425.Large-Scale Location-Aware Services in Access: Hierarchical Building/Floor Classification and Location Estimation Using Wi-Fi Fingerprinting Based on Deep Neural Networks

Author:Kim, KS;Wang, RH;Zhong, ZH;Tan, ZK;Song, HW;Cha, J;Lee, S


Abstract:We report the results of our investigation on the use of deep neural networks (DNNs) for building/floor classification and floor-level location estimation based on Wi-Fi fingerprinting. We propose a new DNN architecture based on a stacked autoencoder for feature space dimension reduction and a feed-forward classifier for multi-label classification with arg max functions to convert multi-label classification results into multi-class classification ones. We also demonstrate a prototype system for floor-level location estimation using received signal strengths measured on XJTLU campus. Our results show the strengths of DNN-based approaches, providing near state-of-the-art performance with less parameter tuning and higher scalability.

5426.A Hybrid MPPT Method for Photovoltaic Systems via Estimation and Revision Method

Author:Ma, JM;Man, KL;Ting, TO;Zhang, N;Lei, CU;Wong, N


Abstract:Maximum Power Point Tracking (MPPT) methods can be classified into direct and indirect approaches. They are used to improve the efficiency of power conversion in Photovoltaic (PV) systems. However, a review of present literature implies that the indirect methods never produce accurate results. Meanwhile, the conventional direct Perturb and Observe (P&O) method has two problems: oscillations at steady state and slow dynamic response under changing environment conditions. Estimation and Revision (ER) method is proposed in this paper to overcome these limitations by the alternative use of MPP estimation and MPP revision process. The efficiency of the ER method is verified in an MPPT system implemented with a specific DC-DC converter and an adopted PV module.

5427.A Denial of Service Attack Method for an IoT System

Author:Liang, LL;Zheng, K;Sheng, QK;Huang, X


Abstract:In recent years, Internet of things (IoT) is widely used in various domains. However, the security of the IoT system becomes a challenge. If the IoT system is attacked, a great property loss will happen. In this paper, a denial of service (DoS) attack to an IoT system is shown. The attack tool is Kali Linux, A Denial of Service (DOS) attack is launched by using 3 different methods. The comparison between the 3 DoS attack methods is also given.

5428.Framework for decentralised architectural design BIM and Blockchain integration

Author:Dounas, T;Lombardi, D;Jabi, W


Abstract:The paper introduces a framework for decentralised architectural design in the context of the fourth industrial revolution. We examine first the constraints of building information modelling in regard to collaboration and trust. We then introduce Blockchain infrastructure as a means for creating new operational and business models for architectural design, through project governance, scaling collaboration nominally to thousands of agents, and shifting trust to the infrastructure rather than the architectural design team. Through a wider consideration of Blockchains in construction projects we focus on the design process and validate our framework with a prototype of BIM design optimisation integrated with a Blockchain mechanism. The paper concludes by outlining the contributions our framework can enhance in the building information modelling processes, within the context of the fourth industrial revolution.

5429.The linguistic servicescape: Speaking their language may not be enough

Author:Touchstone, EE;Koslow, S;Shamdasani, PN;D'Alessandro, S


Abstract:This paper explores Hispanic immigrants' reactions to linguistic servicescapes in retail banking in Southern California. This fertile area of enquiry combines the sociolinguistic theory of linguistic landscape With research into multilingual service encounters describing what happens in the retail servicescape before the service encounter which sets up expectations for what happens during the service encounter. This new term describes the use of language in and around a service encounter including signage and promotional materials as well as bilingual personnel. In multilingual areas such as Southern California where the use of a minority language is politically charged, effective encoding of symbolic language by the service ptovider is crucial for the success of a service encounter. The results of this study indicate that management's actual or perceived lack of sensitivity to appropriate linguistic symbols leads to both confusion and an attribution of discrimination towards the targeted ethnic group even if none were intended. What is written or said in the service encounter is important, but this research illustrates that the context is also significant. The wider symbolic use of language is key in determining the success of service encounters. (C) 2016 Elsevier Inc. All rights reserved.

5430.Are bonds blind? Board-CEO social networks and firm risk

Author:Fan, YY;Boateng, A;Ly, KC;Jiang, YX


Abstract:We examine the impact of social networks between independent directors and the CEO on firm risk. Employing the deaths and retirements of socially connected independent directors and the passage of the 2002 Sarbanes-Oxley Act for two identifications, we find that board-CEO social networks have a positive impact on firm risk. Specifically, CEOs who are socially connected to their independent directors are motivated to adopt riskier investment, operating and financing strategies. This positive influence is more pronounced for prior under-performing firms and for CEOs with low power or overconfidence, indicating that board-CEO social networks act as career insurance and a power-enhancing mechanism to encourage managerial risk-taking.

5431.Outlook and Direction of AI Tour Guide Services - From the Lifelong Machine Learning View

Author:Wang,Shuai;Hong,Xianbin;Karia,Noorliza;Guan,Sheng Uei;Wong,Prudence W.H.;Man,Ka Lok;Liu,Dawei

Source:Proceedings - 2021 2nd International Conference on Electronics, Communications and Information Technology, CECIT 2021,2021,Vol.

Abstract:Artificial intelligence (AI) has entered tourism and become a new service in a tour guide. AI technology can help tourism by providing customized services and attracting visitors to fight with the crisis of the COVID-19 epidemic. This paper introduces how AI tour guide services contribute to tourism and its main issues. The future development of AI tour guides also was discussed at the end and the authors believe lifelong machine learning is the key to developing AI tour guides.

5432.Emotion Recognition Using Representative Geometric Feature Mask Based on CNN


Source:2021 IEEE 4th International Conference on Information Systems and Computer Aided Education, ICISCAE 2021,2021,Vol.

Abstract:Emotion recognition is a growing area of facial recognition, to detect the basic emotion state of a person and then operate further analysis. For practical applications, high speed and accuracy are required as an efficient and precise system. To this end, the paper proposes an effective emotion recognition system using a representative geometric feature mask for feature extraction and a CNN model for classification. Compared with traditional emotion recognition systems, which usually extract facial key features and then convert them into mathematical information variables by equations, the system implemented in this paper extracts necessary features in facial expression through landmarks, and operates a further extraction by a transformation that converts features into a pure geometric feature mask to represent a simplified human face. Then, the mask that can be used to express the human facial emotion with fewer noise features, is input into a deep learning training CNN (Convolutional Neural Network) model. The improvement of this work is that the system combines pure geometric method to extract facial features with CNN algorithm properties in image processing, where local connectivity and shared parameter properties were fully used in further geometric feature extraction. Finally, the system achieves high accuracy and low time costs with KDEF (Karolinska Directed Emotional Faces) and CK+ (Cohn-Kanade AU-Coded Expression Database).

5433.Message from the General Chairs : PlatCon-21

Author:Kim,Mucheol;Man,Ka Lok

Source:2021 International Conference on Platform Technology and Service, PlatCon 2021 - Proceedings,2021,Vol.

5434.Next-generation sequencing reveals fecal contamination and potentially pathogenic bacteria in a major inflow river of Taihu Lake

Author:Vadde, KK;Feng, QL;Wang, JJ;McCarthy, AJ;Sekar, R


Abstract:Taihu Lake is one of the largest freshwater lakes in China and serves as an important source for drinking water. This lake is suffering from eutrophication, cyanobacterial blooms and fecal pollution, and the inflow Tiaoxi River is one of the main contributors. The goal here was to characterize the bacterial community structure of Tiaoxi River water by next-generation sequencing (NGS), paying attention to bacteria that are either fecal-associated or pathogenic, and to examine the relationship between environmental parameters and bacterial community structure. Water samples collected from 15 locations in three seasons, and fecal samples collected from different hosts and wastewater samples were used for bacterial community analysis. The phyla Proteobacteria, Actinobacteria, Bacteroidetes, and Cyanobacteria were predominant in most of the water samples tested. In fecal samples, Bacteroidetes, Firmicutes, and Proteobacteria were abundant, while wastewater samples were dominated by Proteobacteria, Bacteroidetes, Acidobacteria, and Chloroflexi. The cluster analysis and principal coordinate analysis indicated that bacterial community structure was significantly different between water, fecal and sewage samples. Shared OTUs between water samples and chicken, pig, and human fecal samples ranged from 4.5 to 9.8%% indicating the presence of avian, pig and human fecal contamination in Tiaoxi River. At genus level, five bacterial genera of fecal origin and sequences of seven potential pathogens were detected in many locations and their presence was correlated well with the land use pattern. The sequencing data revealed that Faecalibacterium could be a potential target for human-associated microbial source-tracking qPCR assays. Our results suggest that pH, conductivity, and temperature were the main environmental factors in shaping the bacterial community based on redundancy analysis. Overall, NGS is a valuable tool for preliminary investigation of environmental samples to identify the potential human health risk, providing specific information about fecal and potentially pathogenic bacteria that can be followed up by specific methods. (C) 2019 Elsevier Ltd. All rights reserved.

5435.Enhanced Protein Adsorption in Fibrous Substrates Treated with Zeolitic Imidazolate Framework-8 (ZIF-8) Nanoparticles

Author:Fu, H;Ou, PF;Zhu, J;Song, PF;Yang, JQ;Wu, Y


Abstract:Development for new solid substrates for protein adsorption is important, given the massive potential in a number of fields including food production, medicine, biotechnology, and pharmaceutical processing. We developed a zeolitic imidazolate framework 8 (ZIF-8)-nanoparticles based fibrous platform (Platform 1). Its ability in protein adsorption is proven by fluorescence study of Alexa Fluor 647-labeled donkey anti-rabbit IgG adsorbed on Platform 1. Studies reveal that Platform 1 shows much more enhanced protein adsorption compared to a polyethylene terephthalate gauze fibrous platform treated with ZIF-8 nanoparticles. This may be explained by considering that more active sites are enabled on fabric to adsorb a higher amount of ZIF-8 nanoparticles. We show that Platform 1 provides favorable biocompatibility to maintain the bioactivity of enzymes. Furthermore, we prove that a carboxymethylated cotton fabric platform treated with ZIF-8 (Platform 3) can be more capable of immobilizing the Alexa Fluor 647-labeled antibodies than Platform 1. Carboxymethylation helps to enhance protein adsorption in these cotton fabric substrates.

5436.Sim-to-Real Deep Reinforcement Learning for Maximum Power Point Tracking of Photovoltaic Systems

Author:Wang,Kangshi;Ma,Jieming;Man,Ka Lok;Huang,Kaizhu;Huang,Xiaowei

Source:21st IEEE International Conference on Environment and Electrical Engineering and 2021 5th IEEE Industrial and Commercial Power System Europe, EEEIC / I and CPS Europe 2021 - Proceedings,2021,Vol.

Abstract:The maximum power points (MPPs) of photovoltaic (PV) panels vary with atmospheric conditions (solar irradiance, ambient temperature, shading conditions, etc.). Simulation platforms are widely used by engineers and scientists to create models, analyze data, and develop algorithms for the maximum power point tracking (MPPT) of PV systems. However, the behavior, which the algorithm develops in simulations, is usually specific to the characteristics of the models. Strategies that succeed in simulations may not be victoriously transferred to the real world because the modeling errors and sensor noise. In this paper, we create a dynamic model of the PV system only based on the data-sheet from manufacturers. A sim-to-real transfer strategy is proposed for the maximum power point tracking of PV systems. By dynamically randomizing the environments for the agent during the training, the proposed policy can adapt to very different atmospheric conditions. Simulations show that the proposed strategy can maintain a similar level of performance when deployed on the real PV panels.

5437.Achieving sustainability in global sourcing: towards a conceptual framework

Author:Jiang, Y;Jia, F;Blome, C;Chen, LJ


Abstract:Purpose This paper aims to set out the development, based on the extant literature, an integrated conceptual framework for the emergent field of sustainable global sourcing (GS) that synthesizes its antecedents, GS practices and sustainable performance. Design/methodology/approach Conceptual theory building combined with content analysis is used to develop a framework and propositions representing a middle-range theory of sustainable GS. A literature review of the 89 most influential papers is followed by a further discussion based on the resource orchestration perspective (ROP) to advance an integrated conceptual framework. Findings Three main themes are identified from the literature as antecedents, GS practices and sustainable performance, with each theme being detailed in a variety of constructs. Based on the ROP, the relationships between these constructs are revealed, and therefore, an integrated conceptual framework is advanced via three sets of propositions in recourse orchestration breadth, recourse orchestration depth and resource orchestration evolution, respectively. Eight directions for future research are further proposed. Originality/value First, this study provides a comprehensive framework for future study in the emergent field of sustainable GS. Second, the authors contribute to theory development by proposing a ROP to explore the GS practices towards sustainability. Third, the future research directions we proposed can benefit scholars interested in the overlapping areas of GS and sustainability.

5438.Novel SnO2@ZnO hierarchical nanostructures for highly sensitive and selective NO2 gas sensing

Author:Zhang, ZY;Xu, MZ;Liu, L;Ruan, XF;Yan, JF;Zhao, W;Yun, JN;Wang, YN;Qin, SJ;Zhang, T


Abstract:The novel brush-like (B-) SnO2@ZnO hierarchical nanostructures (HNSs) are successfully synthesized by using a simple two-step hydrothermal method. The SnO2 nanowires (NWs) grow epitaxially on the non-polarized plane of ZnO nanorods (NRs) with a six-fold symmetry. The heterogeneous nucleation-growth processes of SnO2 and ZnO are discussed in detail based on the dissolution-recrystallization mechanism, growth kinetics and Ostwald ripening. The excellent sensing performances of B-SnO2@ZnO HNSs for NO2 gas sensor are developed, including good selectivity, ultra-sensitive, fast response, broad detection range and low detection limits. The detection range of the sensor is measured from 5 ppb to 10 ppm, and the detection limit of the sensor is 5 ppb at 150 degrees C. The response and recovery time which reach 90%% of the final signal is less than 60 s, while retaining the low detection limit. The sensing mechanism is also discussed, and the unique structure of B-(SnO2ZnO)-Zn-@ is the dominating parameter for excellent sensing performances. The improved sensing performance of the HNSs also suggests the possibilities of other 1D materials combination for further sensing applications. (c) 2017 Elsevier B.V. All rights reserved.

5439.Energy-Efficient Speed Profile Approximation: An Optimal Switching Region-Based Approach with Adaptive Resolution

Author:Yang, J;Jia, LM;Lu, SF;Fu, YX;Ge, J


Abstract:Speed profile optimization plays an important role in optimal train control. Considering the characteristics of an electrical locomotive with regenerative braking, this paper proposes a new algorithm for target speed profile approximation. This paper makes the following three contributions: First, it proves that under a certain calculation precision, there is an optimal coast-brake switching region-not just a point where the train should be switched from coasting mode to braking mode. This is very useful in engineering applications. Second, the paper analyzes the influence of regenerative braking on the optimal coast-brake switching region and proposes an approximate linear relationship between the optimal switching region and the regeneration efficiency. Third, the paper presents an average speed equivalent algorithm for local speed profile optimization in steep sections. In addition, this paper simplifies the proof of the optimality of smooth running on a non-steep track in two steps. The effects on energy consumption from two important factors (optimal coast and running time) are systematically analyzed. Extensive simulations verify these points of view and demonstrate that the proposed approximation approach is computationally efficient and achieves sufficient engineering accuracy.

5440.Clearing Residual Planetesimals by Sweeping Secular Resonances in Transitional Disks: A Lone-planet Scenario for the Wide Gaps in Debris Disks around Vega and Fomalhaut

Author:Zheng, XC;Lin, DNC;Kouwenhoven, MBN;Mao, SD;Zhang, XJ


Abstract:Extended gaps in the debris disks of both Vega and Fomalhaut have been observed. These structures have been attributed to tidal perturbations by multiple super-Jupiter gas giant planets. Within the current observational limits, however, no such massive planets have been detected. Here we propose a less stringent "lone-planet" scenario to account for the observed structure with a single eccentric gas giant and suggest that clearing of these wide gaps is induced by its sweeping secular resonance. With a series of numerical simulations, we show that the gravitational potential of the natal disk induces the planet to precess. At the locations where its precession frequency matches the precession frequency the planet imposes on the residual planetesimals, their eccentricity is excited by its resonant perturbation. Due to the hydrodynamic drag by the residual disk gas, the planetesimals undergo orbital decay as their excited eccentricities are effectively damped. During the depletion of the disk gas, the planet's secular resonance propagates inward and clears a wide gap over an extended region of the disk. Although some residual intermediate-size planetesimals may remain in the gap, their surface density is too low to either produce superEarths or lead to sufficiently frequent disruptive collisions to generate any observable dusty signatures. The main advantage of this lone-planet sweeping-secular-resonance model over the previous multiple gas giant tidal truncation scenario is the relaxed requirement on the number of gas giants. The observationally inferred upper mass limit can also be satisfied provided the hypothetical planet has a significant eccentricity. A significant fraction of solar or more massive stars bear gas giant planets with significant eccentricities. If these planets acquired their present-day kinematic properties prior to the depletion of their natal disks, their sweeping secular resonance would effectively impede the retention of neighboring planets and planetesimals over a wide range of orbital semimajor axes.
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