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In this work, a new strategy is developed to design and synthesize quaternary catalysts NiS/CdS/MIL-101/PTCs (MIL = Materials of Institute Lavoisier, PTCs = polyoxo-titanium clusters) with excellent photocatalytic activity for H2 evolution. PTCs and NiS can be successfully integrated into CdS/MIL-101 system by multi-step solvothermal in situ reaction method. The as-synthesized photocatalysts integrated with NiS and PTCs exhibit the dramatically enhanced photocatalytic activity for hydrogen evolution, which is approximately 230 times higher than that of uncoupled catalyst CdS/MIL-101. It is more interesting that the photocatalytic activity can be tuned by structural evolution of PTCs. The photoelectrochemical characteristics of catalysts confirm that the drastic enhancement for photocatalytic H2-production activity was predominantly attributed to PTCs and NiS contributing to matching energy gap and improving visible-light response, respectively, and both inhibiting recombination of photogenerated electron-hole pairs. More importantly, this work can flourish the design idea derived from the relation of structure and application for photocatalysts.

Herein, we have extended a reasonable strategy to design and prepare a series of photocatalysts ZIS/MIL-101/PTCs (ZIS = ZnIn2S4, MIL = Materials of Institute Lavoisier, PTCs = Polyoxo-titanium clusters) with evidently enhanced photocatalytic activity for H2 evolution. The synthesis of all photocatalysts was carried out by traditional step-by-step in situ reaction method without special treatment. As expected, the photocatalytic H2 production rates by the three PTCs hybrid catalysts (ZIS/MIL-101/PTCs), namely ZIS/MIL-101/PTC-3, ZIS/MIL-101/PTC-7 and ZIS/MIL-101/PTC-9, were approximately 4, 7 and 12 times higher than that of ZIS/MIL-101, respectively. The results of UV–Vis diffuse reflectance spectroscopy and photoelectric responses show the reasons for boosting photocatalytic activity are that introduction of PTCs can well match energy gap and accelerate the photogenerated charge carriers transfer. This dual functionalization of PTCs can also be further confirmed by the photocatalytic activities of three La-ZIS/MIL-101/PTCs (La-ZIS/MIL-101/PTC-3, La-ZIS/MIL-101/PTC-7 and La-ZIS/MIL-101/PTC-9) photocatalysts doped with the La element.

Chronic kidney disease (CKD) is one of the most serious and prevalent health issues all over the world. The evolution of CKD can last for many years until the death of patients, and the method of treatment mainly includes medication, dialysis, and transplantation with the evolution of the disease. It has been validated by many empirical studies that for severe CKD patients, the optimal treatment is transplantation if a suitable kidney is available, otherwise the patients should initiate dialysis at a suitable time. It has also been validated that the initiation time of dialysis significantly impacts not only the direct treatment results, but also the success of a future possible kidney transplantation. Motivated by this consideration, we investigate the decision-making problem of the optimal treatment approach to maximize the patient’s total reward including pre-transplant reward and post-transplant reward (if applicable), considering the possibility of having a suitable kidney transplantation in the future. A Markov decision process model is established in which the status of the process is described by the patient health status. We present some structural properties of the decision-making problem, which are used to choose the optimal treatment approach in different health status of patients. We collect the clinical data in the simulation experiments to obtain the fitted curves of the evolution process of different CKD patients, and compare the simulation results with the actual clinical data to demonstrate the advantage of our model.

This paper studies the patient flow scheduling problem in a multi-phase-multi-server system setting for a typical ophthalmology clinic, considering different patient flow processes and specific appointment time. In this problem, patients may go through the following processes, i.e., consultation, examination, re-consultation, and treatment, which form four patient flow paths according to different situations. The objective of this paper is to minimize the completion time of all the patients in the ophthalmology clinic. For solving this problem, we develop a hybrid meta-heuristic algorithm EDA–VNS combining estimation of distribution algorithm (EDA) and variable neighborhood search (VNS). We test the suitability of the approach for the ophthalmology clinic’s problem. Computational results demonstrate that the proposed algorithm is capable of providing high-quality solutions within a reasonable computational time. In addition, the proposed algorithm is also compared with several high-performing algorithms to validate its efficiency. The results indicate the advantages of the proposed EDA–VNS algorithm.

Our study explores the factors influencing investors&rsquo, behavior in the peer-to-peer (P2P) lending market in China, and the relationships among them from the perspective of investors. The primary component analysis method was used to divide the P2P lending platforms into five categories. Then, a structural equation model was applied to analyze the interrelationship. Our results show that more exceptional operating ability, profitability, and security of the platform help to improve investor&rsquo, s investment behavior. Operation ability is the most significant influencing factor, which also influences other factors to different degrees. After the analysis of the results, we found that the security degree of P2P lending platforms in China differs, and the risk due to the lack of bank depository for platforms is the most serious. In terms of the background, investors are less interested in the state-owned platforms compared to the bank- or listed-company-owned platforms, although the background strength of the state-owned platforms is more powerful.

Current attempts for sustainable-focused smart community evaluation have failed to make significant advancements, and quantitative analysis for sustainable development is still a major challenge in China. In recent years, smart community evaluation (SCE) for sustainable development has attracted considerable attentions. Government decision-makers can make it easier to stimulate household sustainable consumption by conducting SCE. This paper develops a combined analytical framework that will assist in the process of multi-source data integration and uncertain reasoning of SCE. This framework is used to combine quantitative metrics and subjective judgment with evidential reasoning approach, and this frarmework can also take decision makers’ risk preferences into consideration using prospect theory. Four urban communities are evaluated by the proposed framework to demonstrate its applicability and effectiveness.

We demonstrate amorphous Ge0.92Sn0.08 surface illuminated metal-semiconductor-metal (MSM) photodetectors on flexible substrates for visible wavelength. Photodetection at 633 nm is achieved with an I-V response up to 10-4 A for a 2 V bias voltage. Different evaporation rate effects on the amorphous GeSn MSM photodetector are examined. Bending/strain effects on device performance were studied by evaluating the current density versus voltage characteristics. Amorphous GeSn thin film deposition on polyethylene terephthalate flexible substrate and Ni/Au-GeSn-Ni/Au MSM photodetector finger pattern deposition were performed via thermal evaporation. Photocurrent and dark current densities of amorphous GeSn MSM photodetectors were obtained at 1.36 A/cm2 and 0.24 A/cm2, respectively, where the photocurrent to dark current contrast ratio was found to be equal to 5.6. We also examined the evaporation rate, strain, and bending effect.

Experimental work was undertaken in this study to re-investigate the mechanisms and active species responsible for oxidation of co-contaminants in the Cr(VI)/HSO3− reaction system. Batch experiments showed that the degradation rates of 4-chlorophenol (4-CP) correlated well with the rates of Cr(VI) reduction by sulfite in the same solutions, and that O2(aq) was necessary for the oxidation of 4-CP. Multiple lines of evidences indicate that Cr(VI)/HSO3− reaction is a SO4 −-based oxidation process. SO3 − was generated in Cr(VI)/HSO3− system based on the electron spin resonance spectra, which could be transformed to secondary radicals (SO4 −, SO5 −, and HO ). The contribution of SO5 − was ruled out through almost complete inhibition of methanol (MeOH) on 4-CP degradation. Considering the negligible inhibition of tert-butanol (TBA) on 4-CP degradation, SO4 − was identified to be reactive species in Cr(VI)/HSO3− process. This result was further verified by almost no degradation of nitrobenzene and the inhibiting effect of Cl− in Cr(VI)/HSO3− process. This mechanism is beneficial to application of Cr(VI)/HSO3− system in wastewater treatment.

Compared to the booming industry of AIMDSS, the usage of AIMDSS among healthcare professionals is relatively low in the hospital. Thus, a research on the acceptance and adoption intention of AIMDSS by health professionals is imperative. In this study, an integration of Unified theory of user acceptance of technology and trust theory is proposed for exploring the adoption of AIMDSS. Besides, two groups of additional factors, related to AIMDSS (task complexity, technology characteristics, and perceived substitution crisis) and health professionals’ characteristics (propensity to trust and personal innovativeness in IT) are considered in the integrated model. The data set of proposed research model is collected through paper survey and Internet survey in China. The empirical examination demonstrates a high predictive power of this proposed model in explaining AIMDSS adoption. Finally, the theoretical contribution and practical implications of this research are discussed.

Random yield and uncertain demand usually both exist in many industries, such as the semiconductor industry. In this paper, the price-setting newsvendor model is studied which involves a single manufacturer and a single retailer with random yield and uncertain demand respectively. Under the condition of additive-multiplicative demand, we investigate the varying effects of random yield on the optimal price, order quantity, and expected profit in two situations with different cost structures. The first case is an in-house production case where the firm pays for the raw material quantity it has ordered, and the second one is a procurement case where the firm pays for the real product quantity it receives only. By using the theory of stochastic comparisons, we find that a less variable and a stochastically larger yield rate both lead to a lower optimal price and a higher expected profit for the in-house production case. Moreover, a less variable yield rate also results in a lower optimal price and a higher profit for the procurement case, but this is not true for a stochastically larger yield rate. Numerical examples illustrate that the effect of yield randomness on the optimal order quantity is not general.

Phase transitions in correlated materials can be manipulated at the nanoscale to yield emergent functional properties, promising new paradigms for nanoelectronics and nanophotonics. Vanadium dioxide (VO2), an archetypal correlated material, exhibits a metal–insulator transition (MIT) above room temperature. At the thicknesses required for heterostructure applications, such as an optical modulator discussed here, the strain state of VO2 largely determines the MIT dynamics critical to the device performance. We develop an approach to control the MIT dynamics in epitaxial VO2 films by employing an intermediate template layer with large lattice mismatch to relieve the interfacial lattice constraints, contrary to conventional thin film epitaxy that favors lattice match between the substrate and the growing film. A combination of phase-field simulation, in situ real-time nanoscale imaging, and electrical measurements reveals robust undisturbed MIT dynamics even at preexisting structural domain boundaries and si...

The 53.125 Gbps transmission is experimentally investigated over a next-generation wideband multimode optical fiber (NG-WBMMF) using transmitter optical sub-assemblies (TOSAs) and wideband receiver optical sub-assemblies (ROSAs) developed for 25 Gbps short wavelength division multiplexing (SWDM) operation. A commercial 100 Gbps four-level pulse amplitude modulation integrated circuit (PAM4 IC) evaluation kit with real-time digital signal processing (DSP) is used. Dual wavelength transmission (2 λ × 53.125 Gbps) tests over 300 m of NG-WBMMF are carried out for the wavelength pairs 850, 880 nm and 910, 940 nm with a 4 × 1 optical MUX/DeMUX in the link. Measured pre-forward error correction (FEC) bit error ratio (BER) below the KP4 FEC threshold of 2.4 × 10–4 indicates the feasibility of 100/200 Gbps transmission over NG-WBMMF using a PAM4 chipset with real-time DSP. Single wavelength transmission (1 λ × 53.125 Gbps) using long wavelength TOSAs at 976 and 1066 nm is also studied. Pre-FEC BER below 2.4 × 10–4 is achieved over 300 m at 976 nm and 200 m at 1066 nm. Single wavelength tests from 850 to 940 nm had the same results as the 976 nm wavelength. Thus, this is the first experiment which shows the potential of 400 Gbps transmission with eight SWDM wavelength windows over a single NG-WBMMF using SWDM TOSAs, ROSAs, and commercial 100 Gbps PAM4 chipset.

This paper investigates a single machine serial-batching scheduling problem considering release times, setup time, and group scheduling, with the combined effects of deterioration and truncated job-dependent learning. The objective of the studied problem is to minimize the makespan. Firstly, we analyze the special case where all groups have the same arrival time, and propose the optimal structural properties on jobs sequencing, jobs batching, batches sequencing, and groups sequencing. Next, the corresponding batching rule and algorithm are developed. Based on these properties and the scheduling algorithm, we develop a hybrid VNS–ASHLO algorithm incorporating variable neighborhood search (VNS) and adaptive simplified human learning optimization (ASHLO) algorithms to solve the general case of the studied problem. Computational experiments on randomly generated instances are conducted to compare the proposed VNS–ASHLO with the algorithms of VNS, ASHLO, Simulated Annealing (SA), and Particle Swarm Optimization (PSO). The results based on instances of different scales show the effectiveness and efficiency of the proposed algorithm.

Er 2 Si 2 O 7 and Er 2 Si 2 O 7 /LaMgAl 11 O 19 coatings were fabricated on C f /SiC composites by atmospheric plasma spraying (APS) in order to improve the oxidation resistance of the substrate. Microstructure and oxidation resistant behavior of the coatings were investigated at 1723 K in the thermal shock furnace. The results showed that the as-sprayed coatings were uniformly distributed on the substrate and bonded well with the substrate. The bared substrate has the maximum weight loss of 43.8% after 8 thermal shock cycles with the total heating time of 120 min, while for the samples coated with the Er 2 Si 2 O 7 and Er 2 Si 2 O 7 /LaMgAl 11 O 19 coatings, the weight losses were only up to 3.73% and 1.88%, respectively. Due to the difference of coefficients of thermal expansion between coatings and substrate, the sintering of Er 2 Si 2 O 7 layer, the surface oxidation of substrate and the interfacial reactions between the ceramic layers, the through cracks and horizontal cracks appeared in the coatings with the thermal shock cycle increasing, which significantly led to the increasing weight loss for the coated samples. The oxidation protection of Er 2 Si 2 O 7 and Er 2 Si 2 O 7 /LaMgAl 11 O 19 coatings for C f /SiC composites at 1723 K is much attractive for the short-term application such as several thermal shock cycles with the total heating time of tens of minutes.

Two system transmission experiments are reported which indicate the feasibility of transmitting an aggregated speed of >200 Gb/s over a single next-generation wide-band multimode optical fiber (NG-WBMMF) using a shortwave wavelength division multiplexing (SWDM) and a four-level pulse amplitude modulation (PAM4), using optics rated for ${\text{25 Gb/s}}$ NRZ operation. The first experiment leverages predistorted KR4 ${\text{51.5625 Gb/s}}$ electrical PAM4 signaling generated by an arbitrary waveform generator to drive SWDM TOSAs at 850, 880, 910, and 940 nm. The received optical PAM4 signals are then post processed offline with linear equalizers to improve the eye quality. Detailed analysis of the height and width of the received optical eyes indicates an aggregated ${\text{206.25 Gb/s}}$ speed is achievable on a single NG-WBMMF beyond 150 m. In the second experiment, a commercial PAM4 IC evaluation kit with real-time digital signal processing is adopted to generate and detect PAM4 signals at KP4 FEC rate of ${\text{53.125 Gb/s}}$ per wavelength. The SWDM wavelength range is extended with additional tests at 980 nm. Pre-FEC BER below threshold of ${\text{2.4}}\times {\text{10}}^{-4}$ is achieved up to 300 m across all five wavelengths demonstrating an aggregated speed of ${\text{265.625 Gb/s}}$ over a single MMF.

Yb2SiO5 and NdMgAl11O19 (NMA) powders were synthesized by solid-state reactions. Triple-layer ceramic coatings based on the Si bond layer, Yb2SiO5 interlayer and NMA top layer were prepared on carbon fiber reinforced silicon carbide ceramic matrix (Cf/SiC) composites by atmospheric plasma spraying (APS). The coatings were subjected to thermal shock tests at 1300 °C, 1400 °C and 1450 °C, respectively. The results showed that the Si/Yb2SiO5/NMA coating significantly improved the oxidation resistance of Cf/SiC composites. The failure mechanism of the Si/Yb2SiO5/NMA coating was closely related to the thermal shock temperature. Below 1400 °C, the failure of the coating was connected with the mismatch of thermal expansion coefficient (CTE) between the coating and substrate, the reaction between Yb2SiO5 and NMA at the interface, the poor sintering property of Yb2SiO5 and NMA and the substrate itself. Above 1450 °C, the coating failed after only one thermal shock cycle due to the temperature higher than the melting point of the silicon. Keywords: Coating, Oxidation protection, Atmospheric plasma spraying, Thermal shock test

This article considers the single-machine serial-batching scheduling problem with a machine availability constraint, position-dependent processing time, and time-dependent set-up time. The objectiv ...

Many dynamic events exist in real manufacturing systems, such as arbitrary machine breakdowns and dynamic job arrivals, which makes the scheduling problem even more complicated. In this paper, we address a serial-batching scheduling problem with the above dynamic events. Jobs need to be processed on the serial-batching machines of two manufacturers and then transported by vehicles to a customer for further processing. The objective of the scheduling problem is to minimize the makespan, and the problem is proved to be strongly NP-hard. Some structural properties and a lower bound of the problem are also proved or derived. On the basis of job arrival times, we divide the problem into two phases and propose different rules regarding these two phases. Based on these properties and rules, a heuristic algorithm is developed to solve the problem and its worst case performance is analyzed. The heuristic algorithm is tested on a large set of randomly generated problem instances, and the relative gaps between the found lower bound and the solutions of the proposed heuristic algorithm are reported. The experimental results illustrate the high efficiency and effectiveness of the proposed heuristic algorithm compared with other four classic approaches.

In this paper, we study a scheduling model in which the features of deteriorating jobs, serial batches, multiple job types, and setup times are considered simultaneously. In this proposed model, the jobs of each type are first partitioned into serial batches, and then all batches of different job types are processed on a single serial-batching machine. The actual job processing time is an increasing function of its starting time, and the setup time of the batches is sequence-dependent, i.e., setup time is required only when a new batch is processed first on the machine or immediately after a batch belonging to another job type. We develop optimization algorithms to solve the makespan minimization problem, the maximum tardiness minimization problem, the maximum lateness minimization problem, and the maximum earliness minimization problem, respectively. We also propose optimization algorithms to solve the problem of minimizing the number of tardy jobs under a certain agreeable condition. Finally, we discuss two special cases of the total completion time minimization problem and develop optimization algorithms to solve them.

This paper investigates a scheduling model with certain co-existing features of serial-batching, dynamic job arrival, multi-types of job, and setup time. In this proposed model, the jobs of all types are first partitioned into serial batches, which are then processed on a single serial-batching machine with an independent constant setup time for each new batch. In order to solve this scheduling problem, we divide it into two phases based on job arrival times, and we also derive and prove certain constructive properties for these two phases. Relying on these properties, we develop a two-phase hybrid algorithm (TPHA). In addition, a valid lower bound of the problem is also derived. This is used to validate the quality of the proposed algorithm. Computational experiments, both with small- and large-scale problems, are performed in order to evaluate the performance of TPHA. The computational results indicate that TPHA outperforms seven other heuristic algorithms. For all test problems of different job sizes, the average gap percentage between the makespan, obtained using TPHA, and the lower bound does not exceed 5.41 %.

Motivated by applications in manufacturing industry, we consider a supply chain scheduling problem, where each job is characterised by non-identical sizes, different release times and unequal processing times. The objective is to minimise the makespan by making batching and sequencing decisions. The problem is formalised as a mixed integer programming model and proved to be strongly NP-hard. Some structural properties are presented for both the general case and a special case. Based on these properties, a lower bound is derived, and a novel two-phase heuristic TP-H is developed to solve the problem, which guarantees to obtain a worst case performance ratio of . Computational experiments with a set of different sizes of random instances are conducted to evaluate the proposed approach TP-H, which is superior to another two heuristics proposed in the literature. Furthermore, the experimental results indicate that TP-H can effectively and efficiently solve large-size problems in a reasonable time.

We demonstrate 51.5625Gbps PAM4 transmission over ≥ 150 m next generation wide band MMF using SWDM TOSAs from 850 nm to 940 nm indicating an aggregated 206.25 Gb/s speed achievable on a single WBMMF.

The authors report here a method of protecting the sidewall for the selective release of InGaAsP quantum-well (QW) heterostructure from InP substrates. An intact sidewall secured by SiO2 was demonstrated during the sacrificial layer selective etching, resulting in the suspended InGaAsP QW membranes which were later transferred to the Si substrate with polydimethylsiloxane stamp. The quality of the transferred InGaAsP QW membranes has been validated through photoluminescence and EL measurements. This approach could extend to arbitrary targeting substrate in numerous photonics and electronics applications.