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PurposeAn important objective of human resource (HR) research is to understand how HR practices can influence employee attitudes and behaviors in order to help achieve organizational goals via employee performance. The paper studies the relationship between High Performance Work System (HPWS) and employee service performance (ESP) via organizational support (OS) and organizational identification (OI). On one hand, this may help understand the “black box” between HPWS practices and ESP. On the other hand, while OS refers to employees' evaluations of favorable treatment from the organization and HPWS represent a significant channel the organization uses to communicate its support to employees, OS and OI literatures have not comprehensively examined the effect of HPWS practices on employee OS and OI beliefs.Design/methodology/approachThis study takes a quantitative approach and employs hierarchical regression from a sample of 467 employees in 10 commercial banks in Sierra Leone.FindingsThe results show a positive relationship between HPWS practices and ESP and at the same time OS and OI partially mediate the relationship, suggesting that employees draw inferences from the HPWS-related treatment they receive in assessing the supportiveness of the organization.Research limitations/implicationsIn this study, the authors put forth an innovative conceptual model of performance management by testing the relationships which have not been tested before, especially in a new context of banking industry in Sierra Leone. By implementing HPWS practices that demonstrate the organization cares about the employees' well-being and values their contribution, organizations are likely to be perceived as offering high levels of support for the employees.Originality/valueThe results of this study add to our knowledge about the antecedents of OS and OI. Moreover, while OS and OI research has been largely rooted in the organizational behavior literature, this study bridges the human resource literature and the organizational behavior literature, by combining HPWS, OS, OI and ESP.

Chronic myelomonocytic leukemia (CML) is a myeloid tumor characterized by MDS (myelodysplastic syndrome) and MPN (myeloproliferative neoplasms). Allogeneic hematopoietic stem cell transplantation, chemotherapy, interferon, and targeted therapy are the main treatment methods for CML. Tyrosine kinase inhibitors (TKIs) are also a treatment option, and patients are currently recommended to take these drugs throughout their lives to prevent CML recurrence. Therefore, there is a need to investigate and identify other potential chemotherapy drugs. Currently, research on CML treatment with a single drug has shown little progress. Fingolimod (FTY720), an FDA-approved drug used to treat relapsing multiple sclerosis, has also shown great potential in the treatment of lymphocytic leukemia. In our study, we find that FTY720 and curcumol have a significant inhibitory effect on K562 cells, K562/ADR cells, and CD34+ cells from CML patients. RNAseq data analysis shows that regulation of apoptosis and differentiation pathways are key pathways in this process. Besides, BCR/ABL-Jak2/STAT3 signaling, PI3K/Akt-Jnk signaling, and activation of BH3-only genes are involved in CML inhibition. In a K562 xenograft mouse model, therapy with curcumol and FTY720 led to significant inhibition of tumor growth and induction of apoptosis. To summarize, curcumol and FTY720 synergistically inhibit proliferation involved in differentiation and induce apoptosis in CML cells. Therefore, synergistic treatment with two drugs could be the next choice of treatment for CML.

Structure from Motion (SfM) is a series of methods for reconstructing scene structure (i.e.three-dimensional space points) and camera motion (i.e.camera pose) from an image set. In this paper, aimed at the low accuracy of the global reconstruction, the robustness to external points and the time-consuming incremental reconstruction, a fast, closed-loop and high precision reconstruction method is proposed. The method is based on the SIFT matching algorithm GeoMatch, which is constrained by geometric structure of the scene and by numerical and statistical characteristics of feature invariant scale transformation. Experiments show that GeoMatch outperforms both traditional tree-based and hash-based matching methods in terms of time and accuracy.

In this paper, we integrate the advantages of convolutional neural network (CNN) and bidirectional recurrent neural network (BiRNN) with attention mechanism, and propose a CNN-BiRNN based method to recognize the individual high resolution range profile (HRRP). In the proposed method, the CNN is utilized to explore the spatial correlation of raw HRRP data and extract expressive features followed by a BiRNN taking the full consideration of temporal dependence between range cells. Furthermore, in order to enhance the robustness to misalignment, an attentional mechanism is employed after BiRNN to allow the CNN-BiRNN model to focus on the discriminative target area. The combination of CNN and BiRNN with attention mechanism makes the extracted features are not only efficient, but also strongly resistant to the time-shift sensitivity. Experimental results on measured HRRP data demonstrate the effectiveness and the robustness to misalignment of the proposed method.

Computerized adaptive testing (CAT) is a testing mode based on measurement theory and computer technology. Firstly, this article briefly introduces the definition and advantages of computerized adaptive testing. Moreover, this study uses web of science retrieval tools and CiteSpace software to analyze the literature related to CAT technology from 1990 to 2020, and the problems and countermeasures in CAT application are briefly described, Finally, the future development trend of computer adaptive testing is depicted.

This paper improves visual-inertial systems to boost the localization accuracy for low-cost rescue robots. When robots traverse on rugged terrain, the performance of pose estimation suffers from big noise on the measurements of the inertial sensors due to ground contact forces, especially for low-cost sensors. Therefore, we propose \textit{Threshold}-based and \textit{Dynamic Time Warping}-based methods to detect abnormal measurements and mitigate such faults. The two methods are embedded into the popular VINS-Mono system to evaluate their performance. Experiments are performed on simulation and real robot data, which show that both methods increase the pose estimation accuracy. Moreover, the \textit{Threshold}-based method performs better when the noise is small and the \textit{Dynamic Time Warping}-based one shows greater potential on large noise., accepted by IFAC World Congress 2020

In this paper, we employ an interference model of two separated electric dipoles to study the color-dependent unidirectional scattering of a plasmonic heterodimer consisting of a pair of gold and silver disks of the same size. The dipole moments in such a dipole-dipole interference model are numerically obtained by a multipole decomposition method. It shows that the power difference between the different scattering directions predicted by the dipole-dipole interference model agrees well with that calculated by the full wave simulation. The dipole-dipole interference model indicates that the scattering directionality of the heterodimer is intimately related to its geometrical parameters, including the height and radius of the disk as well as the distance between two disks. We further show that the color routing of such a heterodimer is also maintained when an electric or magnetic dipole source is positioned in the center of the heterodimer. Finally, we propose an approach to enhance bidirectional scattering by arranging the heterodimer in a line and then the main lobe beamwidth can be reduced to about 26 deg for the right scattering and 29 deg for the left scattering. Our results may be used in designing integrated plasmonic nanocircuits that demand light guiding and routing in nanoscale.

Reciprocal Personal/Public Protection (RPPP) featured with source control is introduced, Facepiece Discriminating Mouth and Nose (FDMN) is employed to serve the purpose, which includes polymer based mouth cover with optional nose cover. The new knowledge that mouth is a primary, active and dominant source of the virus has been well established, which is the base of FDMN. Source classification and related source control tools are discussed, mouth cover is recommended as the tool prioritized to use. Liquid droplets is identified as a hard issue related to mask, liquid droplets, mask fitting, comfort and facial recognition constitute real challenges of mask in addition to efficiency, All of these have been addressed with FDMN. Comparisons between FDMN and masks/face covering are taken on four aspects: efficiency and efficacy, tolerance and comfort, cost and waste, and civil rights and public interest. Mouth cover is recommended to replace the face covering and act as both a personal tool and a public utensil, mouth cover with nose cover can provide better protection than N95 etc. RPPP with FDMN, could be an alternative for lockdown, a parallel strategy to vaccine, and a collectively living way during the pandemic era. FDMN, featured with high efficiency protection, high degree comfort, easy wearing, tight-fitting, easy facial recognition & communication, reusability, cost-effective, environment friendly and scale manufacturing more readily and widely etc., is a simple and sustainable solution, which is essential for ordinary people to keep wearing it properly for protection.

A multi-band multiwavelength erbium-doped fiber laser (MBMEFL) based on the combined four wave mixing effect (FWM) and self-seeding stimulated Brillouin scattering (SSBS) effect has been studied experimentally. We use two ring cavities which consist of a large and a small cavity to build up this MBMEFL. The output multiple bands and multiple wavelengths are depended on the EDFA power and the length of the single mode fiber (SMF). With a proper length of SMF, we can achieve multi-band lasing by FWM effect and multiwavelength lasing in these bands by SSBS. By increasing the EDFA power, the multi-band multiwavelength lasing signals from the MBMEFL decrease.

In the past few years, deep learning have attracted increasing attention for HRRP-based radar automatic target recognition(RATR) because of their powerful ability to learn features from training data automatically. However, recent studies show that deep learning models are vulnerable to adversarial examples. In this paper, we verified adversarial examples also exist in the deep learning based HRRP target recognition. A novel adversarial attack algorithm called Robust HRRP Attack(RHA) is proposed to generate robust adversarial perturbations in realworld. Experimental results on measured HRRP data show that RHA decrease HRRP recognition performance significantly which indicate our method is efficient and robust.

Flippers are essential components of tracked robot locomotion systems for unstructured terrain, especially within a rescue scenario. Achieving full and semi-autonomy for such rescue robots is the goal of many research efforts. In this work, we propose an algorithm to plan the morphologies of a small rescue robot with four flippers to get over 3D ground without any extra sensors, such as pressure sensors. To achieve the goal, we simplify the rescue robot as a skeleton on inflated terrain. Its morphology can be represented by configurations of several parameters. Then we plan the mobile robot's movement on 3D terrain with four individually manipulated flippers. We perform real robot experiments on three different obstacles. The results show that we move the flippers very effectively and are thus able to tackle those terrains very well.

A novel high-resolution range profile (HRRP) target recognition method based on attentional convolutional neural network (CNN) model with multi-resolution spectrograms is proposed. Different from time domain HRRP, the multi-resolution spectrograms record the amplitude feature and characterize the phase information among range cells of the target at different time-frequency resolutions. The attentional CNN consists of several feature extractors and an attention mechanism to softly weight features extracted from multi-resolution spectrograms. Experimental results on measured HRRP data demonstrate the effectiveness of the proposed method, and diagnostically visualize the importance of the spectrogram at different resolutions.

For rescue robots, flippers endow the robot with additional ability to pass through various terrain. Also, autonomous capabilities become more important, especially with respect to autonomous motion including flippers. In recent work, autonomy for flippers is done by either planning with several special states or based on collected data. We are considering if it is possible to find a way to build continuous states without collecting old trail data. In this paper, we first model the possible states as a global planning path with parameter configuration of the scene. Then, we follow the path to achieve the autonomous run. We plot the morphology of each path points to show the correctness of the path and implement a simple path following on real robot to demonstrate the performance of our algorithm.

In this paper, we theoretically analyze the optical force between a pair of active and passive plasmonic core-shell nanoparticles (NPs). The optical force between the NPs can be either attractive or repulsive near the critical point while the passive dimer provides only attractive force. We reveal that the reversal of attractive or repulsive force is determined by the relative phase of electric dipole (ED) modes, which can be strongly affected by the gain and loss coefficient κ. Compared with the passive dimer with the same size, the active-passive dimer can exhibit a very high repulsive force (about two orders of magnitude) while remaining the same order magnitude attractive force when the value of coefficient is 0.345. Interestingly, we find that the position of the maximum repulsive force occurs near the critical point. We also investigate the influence of variations in geometrical parameters of the dimer and polarization angle on the force. Finally, the numerical results demonstrate that when the dimer is illuminated by a laser beam, the attractive and repulsive forces can also be achieved. The manipulation of optical force can find potential in optical sorting and transport of NPs.

In this work, we design and numerically demonstrate a touching dielectric nanoantenna with high directionality. This antenna consists of a dielectric cuboid dimer with different heights, and there are no gaps between the subunits of the dimer. Superior unidirectional scattering is achieved when the electric and magnetic dipolar modes inside the antenna satisfy the first Kerker condition. This unidirectional scattering is much more prominent than its components (i.e., the dielectric cuboid nanoantennas with different heights) in the considered spectral region. Furthermore, the radiation angle can be tailored in a 10-degree range by properly rotating the antenna along the out of axis. The off-normal scattering is due to the interference between one induced magnetic dipole and two electric dipoles inside the nanoantenna. Furthermore, we also demonstrate that similar unidirectional scattering effect can also be maintained when the antenna is close to an electric (or magnetic) dipole source, and the forward emission direction can be efficiently controlled by the relative position of the dipole source. Finally, we show that it is possible to further enhance the unidirectionality by arranging the antenna in an array and the main lobe angular beam width of the 2D far-field pattern can be reduced to 28 degree.

Mapping is an essential task for mobile robots and topological representation often works as a basis for the various applications. In this paper, a novel framework that can build topological maps incrementally is proposed. The algorithm is using a distance map, and in our framework the topological map can grow as we append more sensor data to the map. To demonstrate our algorithm, we show the result of the distance map based method on several popular maps and run the incremental framework with raw sensor data to have a growing topological map, as an example of a robot exploring the environment., Comment: Accepted at IEEE RCAR 2019

In this paper, we demonstrate our work on Gaussian Process Occupancy Mapping (GPOM). We concentrate on the inefficiency of the frame computation of the classical GPOM approaches. In robotics, most of the algorithms are required to run in real time. However, the high cost of computation makes the classical GPOM less useful. In this paper we dont try to optimize the Gaussian Process itself, instead, we focus on the application. By analyzing the time cost of each step of the algorithm, we find a way that to reduce the cost while maintaining a good performance compared to the general GPOM framework. From our experiments, we can find that our model enables GPOM to run online and achieve a relatively better quality than the classical GPOM., Comment: Accepted to ICARCV2018

Dependency on energy is much higher than the past and it is clear that energy is vital for a sustainable and safer future. Therefore, urgent solutions are required not only to increase share of renewable resources but also more efficient usage of fossil fuels. This could be achieved with innovative power, air conditioning and refrigeration cycles utilising ‘long-term sustainable’ (LTS) fluids, especially air, water and CO2. In the article we provide a rational approach to the future use of working fluids based on our interpretation of the available technical evidence. We consider it self-evident that volatile fluids will continue to play major roles in cooling and power generation, however, new technologies will be needed that optimise energy efficiency and safety with minimum environmental impact. Concordantly we discuss the past and current situation of volatile fluids and present four innovative technologies using air/water cycles. Study results showed that there is a rapid development in heating, cooling and power generation technologies those use water/air as working fluid. These technologies demonstrate a potential to replace conventional systems, thereby to contribute to global sustainability in near future. However, further development on LTS fluids and materials also process intensification and cost reduction are vital parameters for future advancement of these technologies.

In this Letter, we investigate the packet error rate (PER) performance of digital pulse interval modulation (DPIM) for free-space optical (FSO) links under the combined effect of turbulence and pointing errors. The theoretical model is developed by considering the effect of some important parameters, including turbulence condition, beamwidth, receiver aperture size, jitter variance, data rate, transmitted optical power, etc. A closed-form average PER expression for DPIM is derived for this fading channel. The results of numerical simulation are further provided to verify the validation of our model. This work can be helpful for selecting DPIM in the FSO system design.

Corresponding author: yaoyong@hit.edu.cnReceived January 30, 2013; accepted March 10, 2013; posted online July 17, 2013A closed-form bit-error rate (BER) expression is derived for free-space optical (FSO) communicationsystems with circle polarization shift keying and spatial diversity receivers in the gamma-gamma (GG)distribution fading channel. This model can predict the performance without the need of lengthy simula-tion runs. The performance can be analyzed by some system parameters such as atmospheric conditions,link length, communication wavelength, receiver aperture size, and number of spatial diversity receivers.Numerical results demonstrate the influence of the above parameters on the FSO systems and show quan-titatively the differences in behavior among various different parameters.OCIS codes: 010.1300, 010.1330, 060.2605, 060.4080.doi: 10.3788/COL201311.S20101.

Conventional seismic data processing methods based on post-stack time migration have been playing an important role in coal exploration for decades. However, poststack time migration processing often results in low-quality images in complex geological environments. In order to obtain high-quality images, we present a strategy that applies the Kirchhoff prestack time migration (PSTM) method to coal seismic data. In this paper, we describe the implementation of Kirchhoff PSTM to a 3D coal seam. Meanwhile we derive the workflow of 3D Kirchhoff PSTM processing based on coal seismic data. The processing sequence of 3D Kirchhoff PSTM includes two major steps: 1) the estimation of the 3D root-mean-square (RMS) velocity field; 2) Kirchhoff prestack time migration processing. During the construction of a 3D velocity model, dip moveout velocity is served as an initial migration velocity field. We combine 3D Kirchhoff PSTM with the continuous adjustment of a 3D RMS velocity field by the criteria of flattened common reflection point gathers. In comparison with post-stack time migration, the application of 3D Kirchhoff PSTM to coal seismic data produces better images of the coal seam reflections.

PurposeA firm will seek an optimal balance between internal R&D and technology outsourcing when formulating its innovation strategy. This paper aims to provide a review of the determinants of firm's innovation strategy, and performs an empirical study on a sample from Chinese high‐tech industry, with the purpose of identifying two aspects of the issue: the choice patterns of Chinese firms over innovation strategy, and the innovation effect elasticity of different strategies.Design/methodology/approachThe development of a multiple regression model supported by data from industry level and a statistic analysis.FindingsOutsourcing is the major innovation strategy adopted by most Chinese high‐tech firms, especially technology import, which implies the imperfection of Chinese innovation service system. The empirical analysis also indicates the insufficiency of internal R&D expenditure and the weakness of absorptive capacity in Chinese high‐tech firms. Although, Chinese high‐tech firms prefer the outsourcing strategy in their innovation, the contribution of outsourcing is much smaller than that of internal R&D. When expenditures are increased by the same rate, the innovation output form internal R&D is twice the output of outsourcing. For improving Chinese firms' innovation efficiency, the reform of innovation service system is needed on the macro‐level, while on the micro‐level, it calls for firms to readjust their innovation strategy portfolio.Originality/valueThis paper will make up for the deficiency in current researches on innovation, which often apply firm samples in developed countries, and lack evidences from firm samples in developing countries. In addition, it will provide the decision‐making basis for Chinese Government's current actions in constructing and improving China's innovation service system.

We numerically and experimentally study a multiwavelength fiber laser (MWFL) employing a nonlinear Brillouin optical loop mirror (NBOLM). Taking into account the impact of stimulated Brillouin scattering (SBS) effect on nonlinear polarization evolution, we present the power transmission equation of Stokes lines from the NBOLM. Thereafter, we combine the power transmission equation, coupled wave equations of SBS process in NBOLM, rate and power propagation equations in the erbium-doped fiber (EDF) to build up a model for the MWFL. Using this model, we can explain the impacts of EDF pump power, input polarization state and quarter-wave-plate angle on the number and amplitude flatness of output Stokes lines. Furthermore, the results from numerical calculations are verified by the experimental measurements.

Major equipment manufacturing industry is the strategic industry of national defense construction. In the 1990s, China began implementing the "market for technology" strategy, but the strategy did not achieve the desired results, for the important technology and equipment is still highly dependent on imports. The paper analyses the risk aversion characteristics of the owners to purchase, and points out that the risk aversion characteristics comes from the product attributes of important equipment manufacturing industry and asymmetric information. Then it elaborates a dynamic game model to study on the choices of the enterprise’s technological innovation modes in the major equipment manufacturing industry. Finally, the paper concludes that under the strong risk aversion constraints, rational companies will choose collaborative innovation instead of independent innovation.

Importance has been attached to trade finance innovation for it is essential for the competitiveness of commercial banks. Its risks mainly come from three aspects: market innovation, institutional innovation and portfolio innovation. These are the source of innovation risks. Based on the classification of innovation risks, identification framework and evaluation indicator system are introduced to manage the risks so as to ensure the success of trade finance innovation.

From the point of view of bank process reengineering theory, the paper focuses its discussion on definition and features of international trade financing based on the principles and requirements of financial innovation. Through the clarification for international trade financing process and comparison for ways of international trade financing under traditional trade settlement methods, trade financing process innovation has been fulfilled.

E-commerce represents a new way of conducting business transactions. The unique characteristics of e-commerce make it a potential value driver for electricity companies who have to focus on value creation after experienced significant structural changes. Creating value with e-commerce needs proper strategies. In this paper, we discuss three strategic alternatives for electricity companies: strengthening the supply chain, increasing product and service profile, and redefining the relationship with customers by cyber auctions.

We have proposed and demonstrated a novel switchable single-longitudinal-mode (SLM), dual-wavelength erbium-doped fiber laser (DWEDFL) assisted by Rayleigh backscattering (RBS) in a tapered fiber in a ring laser configuration. The RBS feedback in a tapered fiber is a key mechanism as linewidth narrowing for laser output. A compound laser cavity ensured that the EDFL operated in the SLM state and a saturable absorber (SA) is employed to form a gain grating for both filtering and improving wavelength stability. The fiber laser can output dual wavelengths simultaneously or operate at single wavelength in a switchable manner. Experiment results show that with the proper SA, the peak power drift was improved from 1–2 dB to 0.31 dB and the optical signal to noise ratio was higher than 60 dB. Under the assistance of RBS feedback, the laser linewidths are compressed by around three times and the Lorentzian 3 dB linewidths of 445 Hz and 425 Hz are obtained at 1550 nm and 1554 nm, respectively. Published version

We reported on the generation of the dual-wavelength rectangular pulse in an erbium-doped fiber laser (EDFL) with a topological insulator saturable absorber. The rectangular pulse could be stably initiated with pulse width from 13.62 to 25.16 ns and fundamental repetition rate of 3.54 MHz by properly adjusting the pump power and the polarization state. In addition, we verified that the pulse shape of the dual-wavelength rectangular pulse can be affected by the total net cavity dispersion in the fiber laser. Furthermore, by properly rotating the polarization controllers, the harmonic mode-locking operation of the dual-wavelength rectangular pulse was also obtained. The dual-wavelength rectangular pulse EDFL would benefit some potential applications, such as spectroscopy, biomedicine, and sensing research.

A model of multiwavelength erbium-doped fiber laser (MEFL), which takes into account the impact of fiber attenuation on the four-wave-mixing (FWM), is proposed. Using this model, we numerically study the output characteristics of the MEFL based on FWM in a dispersion shift fiber with two seeding light signals (TSLS) and experimentally verify these characteristics. The numerical and experimental results show that the number of output channels can be increased with the increase of the erbium-doped fiber pump power. In addition, by decreasing the spacing of TSLS and increasing the power of TSLS, the number of output channels can be increased. However, when the power of TSLS exceeds a critical value, the number of output channels decreases. The results by numerical simulation are consistent with experimental observations from the MEFL.

We experimentally demonstrate a multi-wavelength ultrafast erbium-doped fiber laser incorporating a μm-scale topological insulator: Bi2Se3/Polyvinyl Alcohol film as both an excellent saturable absorber for mode-locking and a high-nonlinear medium to induce a giant third order optical nonlinear effect for mitigating the mode competition of erbium-doped fiber laser and stabilizing the multi-wavelength oscillation. By properly adjusting the pump power and the polarization state, the single-, dual-, triple-, four-wavelength mode-locking pulse could be stably initiated. For the four-wavelength operation, we obtain its pulse width of ∼22 ps and a fundamental repetition rate of 8.83 MHz. The fiber laser exhibits the maximum output power of 9.7 mW with the pulse energy of 1.1 nJ and peak power of 50 W at the pump power of 155 mW. Our study shows that the simple, stable, low-cost multi-wavelength ultrafast fiber laser could be applied in various potential fields, such as optical communication, biomedical research, and radar system.

We experimentally study the dependences of high-order Stokes lines on the erbium-doped fiber (EDF) pump power PEDF, the Brillouin pump (BP) power PBP, and its working wavelength in a multiwavelength Brillouin erbium-doped fiber laser (MBEFL). By using the rate and propagation equations, and the coupled wave equations of stimulated Brillouin scattering, we establish a lumped model to describe the MBEFL. Numerical simulations show that the number of Stokes lines can be increased by decreasing the spacing between the BP wavelength and the EDF peak gain or PBP as long as it is larger than a critical value PBP(cr)=1.7 mW, or by increasing PEDF without reaching a saturation value PEDF(cr)=250 mW. However, when PBP and PEDF are varied beyond PBP(cr) and PEDF(cr), respectively, the number of Stokes lines is reduced, accompanied by some self-lasing cavity modes. These results by numerical simulation are consistent with experimental observations from the MBEFL.