Design of a Hardware-Implemented Phase Calculating System for Feedback Control in the LHCD Experiments on EAST

A fully hardware-implemented phase calculating system for the feedback control in the lower-hybrid current drive （LHCD） experiments is presented in this paper. By taking advantages of field programmable gate array （FPGA） chips with embedded digital signal processing （DSP） cores and the Matlab-aided design method, the phase calculating algorithm with a square root operation and parallel process are efficiently implemented in a single FPGA chip to complete the calculation of phase differences fast and accurately in the lower-hybrid wave （LHW） system on EAST.

NEW METHODS FOR CALCULATING ACTIVITIES OF COMPONENTS FROM PHASE DIAGRAMS IN BINARY PERITECTIC SYSTEMS

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CALCULATING ACTIVITIES USING Δfus H（Aη）（ Bξ） AND CALCULATION OF ACTIVITIES IN Ga-As, Ga-Sb AND In-Sb SYSTEMS

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Rapidly calculating the partition function of macroscopic systems

It has remained an open problem to accurately compute the partition function of macroscopic systems since the establishment of statistical physics. A rapid method approaching this problem was presented and was strictly tested by molecular dynamic （MD） simulations on Ar atoms in both dense gaseous and liquid states. The outcomes from the method on the internal energy and the work of isothermal expansion （and therefore the free energy） are in good agreement with the MD simulations, suggesting the method would be immediately applied in vast areas.

Sequential Inverse Optimal Control of Discrete-Time Systems

This paper presents a novel sequential inverse optimal control(SIOC)method for discrete-time systems,which calculates the unknown weight vectors of the cost function in real time using the input and output of an optimally controlled discrete-time system.The proposed method overcomes the limitations of previous approaches by eliminating the need for the invertible Jacobian assumption.It calculates the possible-solution spaces and their intersections sequentially until the dimension of the intersection space decreases to one.The remaining one-dimensional vector of the possible-solution space’s intersection represents the SIOC solution.The paper presents clear conditions for convergence and addresses the issue of noisy data by clarifying the conditions for the singular values of the matrices that relate to the possible-solution space.The effectiveness of the proposed method is demonstrated through simulation results.

Exploration of Earth-Abundant Transition Metals(Fe,Co,Ni)Doped on W_(18)O_(49) System as Electrocatalysts for Urea Productiont

The conversion of inert N_(2) and CO_(2) into urea by electrocatalytic technology not only reduces the cost of urea synthesis in future,but also alleviatesthe environmental pollution problem caused by carbon emission in traditional industrial production.However,facing downside factors such as strong competitive reactions and unclear reaction mechanism,the design of high-performance urea catalysts is imminent.This study demonstrates that W_(18)O_(49) system doped heteronuclear metals(TM=Fe,Co,Ni)can effectively solve the problem of competitive adsorption between N_(2) and CO_(2) and realize the co-adsorption of N_(2) and CO_(2) at diverse sites.Their theoretical limiting voltages for urea production on TM-W_(18)O_(49)(TM=Fe,Co,Ni)systems are-0.46 V,-0.42 V and-0.52 V,respectively.The results are all lower than that of the contrastive voltage in pristine W_(18)O_(49) system(-0.91 V),further indicating the rationality and necessity of single-atom doped strategy for the co-reduction of two molecules.Specially,Co-W_(18)O_(49) can theoretically inhibit the side reactions of NRR,CO_(2)RR,and HER,which deserve future experimental exploration in future.The study suggests that doping heteronuclear metal into transition metal oxides is a feasible scheme to solve competitive adsorption and improve catalytic performance.

Rapid Parameter-Optimizing Strategy for Plug-and-Play Devices in DC Distribution Systems under the Background of Digital Transformation

By integrating advanced digital technologies such as cloud computing and the Internet of Things in sensor measurement,information communication,and other fields,the digital DC distribution network can efficiently and reliably access DistributedGenerator(DG)and Energy Storage Systems(ESS),exhibiting significant advantages in terms of controllability and meeting requirements of Plug-and-Play(PnP)operations.However,during device plug-in and-out processes,improper systemparametersmay lead to small-signal stability issues.Therefore,before executing PnP operations,conducting stability analysis and adjusting parameters swiftly is crucial.This study introduces a four-stage strategy for parameter optimization to enhance systemstability efficiently.In the first stage,state-of-the-art technologies in measurement and communication are utilized to correct model parameters.Then,a novel indicator is adopted to identify the key parameters that influence stability in the second stage.Moreover,in the third stage,a local-parameter-tuning strategy,which leverages rapid parameter boundary calculations as a more efficient alternative to plotting root loci,is used to tune the selected parameters.Considering that the local-parameter-tuning strategy may fail due to some operating parameters being limited in adjustment,a multiparameter-tuning strategy based on the particle swarm optimization(PSO)is proposed to comprehensively adjust the dominant parameters to improve the stability margin of the system.Lastly,system stability is reassessed in the fourth stage.The proposed parameter-optimization strategy’s effectiveness has been validated through eigenvalue analysis and nonlinear time-domain simulations.

Comparative evaluation of artificial intelligence systems'accuracy in providing medical drug dosages:A methodological study

BACKGROUND Medication errors,especially in dosage calculation,pose risks in healthcare.Artificial intelligence(AI)systems like ChatGPT and Google Bard may help reduce errors,but their accuracy in providing medication information remains to be evaluated.AIM To evaluate the accuracy of AI systems(ChatGPT 3.5,ChatGPT 4,Google Bard)in providing drug dosage information per Harrison's Principles of Internal Medicine.METHODS A set of natural language queries mimicking real-world medical dosage inquiries was presented to the AI systems.Responses were analyzed using a 3-point Likert scale.The analysis,conducted with Python and its libraries,focused on basic statistics,overall system accuracy,and disease-specific and organ system accuracies.RESULTS ChatGPT 4 outperformed the other systems,showing the highest rate of correct responses(83.77%)and the best overall weighted accuracy(0.6775).Disease-specific accuracy varied notably across systems,with some diseases being accurately recognized,while others demonstrated significant discrepancies.Organ system accuracy also showed variable results,underscoring system-specific strengths and weaknesses.CONCLUSION ChatGPT 4 demonstrates superior reliability in medical dosage information,yet variations across diseases emphasize the need for ongoing improvements.These results highlight AI's potential in aiding healthcare professionals,urging continuous development for dependable accuracy in critical medical situations.

First principles calculation of intermetallic compounds in FeTiCoNiVCrMnCuAl system high entropy alloy

The structural, electronic and elastic properties of common intermetallic compounds in FeTiCoNiVCrMnCuAI system high entropy alloy were investigated by the first principles calculation. The calculation results of formation enthalpy and cohesive energy show that FeTi, Fe2Ti, AlCrFe2, Co2Ti, AlMn2V and Mn2Ti phases may form in the formation process of the alloy. Further studies show that FeTi, FezTi, AlCrFe2, Co2Ti and AlMn2V phases with higher shear modulus and elastic modulus would be excellent strengthening phases in high entropy alloy and would improve the hardness of the alloy. In addition, the partial density of states was investigated for revealing the bonding mode, and the analyses on the strength of p-d hybridization also reveal the underlying mechanism for the elastic properties of these compounds.

Calculating models on surface tension of RE_2O_3-Mg O-SiO_2(RE=La, Nd, Sm, Gd and Y) melts

A thermodynamic model was developed for determining the surface tension of RE2O3-MgO-SiO2(RE=La, Nd, Sm, Gd and Y) melts considering the ionic radii of the components and Butler's equation. The temperature and composition dependence of the surface tensions in molten RE2O3-MgO-SiO2 slag systems was reproduced by the present model using surface tensions and molar volumes of pure oxides, as well as the anionic and cationic radii of the melt components. The iso-surface tension lines of La2O3-MgO-SiO2 slag melt at 1873 K were calculated and the effects of slag composition on the surface tension were also investigated. The surface tensions of La2O3, Gd2O3, Nd2O3 and Y2O3 at 1873 K were evaluated as 686, 677, 664 and 541 m N/m, respectively. The surface tension of pure rare earth oxide melts linearly decreases with increasing cationic field strength, except for Y2O3 oxide, while Y2O3 has a much weaker surface tension. The evaluated results of the surface tension show good agreements with literature data, and the mean deviation of the present model is found to be 1.05% at 1873 K.

Plotting and application of predominance area diagram of In-S-O system based on topological rules

The mathematical topological rule was proposed to plot the predominance area diagram.Based on the phase rules,the components of In-S-O system were analyzed and the coexisting points of three condensed phases were determined.Combined with the topological rules and thermody namic calculation,four relation diagrams between the coexisting points of three condensed phases,which were denoted as α,β stable plane-topological diagram and unstable plane-topological diagram,were plotted for the In-S-O system.The results show that α stable plane topological diagram is in accordance with the predominance area diagram of In-S-O system plotted by traditional methods,which indicates that the new method is feasible to plot the predominance area diagram of In-S-O system.Meanwhile,β unstable plane-topological diagram can be used to elucidate the indium production with the bath smelting process.

The Relationship between the Area of Aquaculture Pond and Purification Pond in Water Circulation Aquaculture System

The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.

First-Principles Study of Magnetism in Transition Metal Doped Na0.5Bi0.5TiO3 System

The origins of magnetism in transition-metal doped Na0.5Bi0.5TiO3 system are investigated by ab initio calculations. The calculated results indicate that a transition-metal atom sub- stitution for a Ti atom produces magnetic moments, which are due to the spin-polarization of transition-metal 3d electrons. The characteristics of exchange coupling are also calculated, which shows that in Cr-/Mn-/Fe-/Co- doped Na0.5Bi0.5TiO3 system, the antiferromagnetic coupling is favorable. The results can successfully explain the experimental phenomenon that, in Mn-/Fe- doped Nao.sBio.sTiO3 system, the ferromagnetism disappears at low tem- perature and the paramagnetic component becomes stronger with the increase of doping concentration of Mn/Fe/Co ions. Unexpectedly, we find the Na0.5Bi0.5Ti0.67V0.33iO3 sys- tem with ferromagnetic coupling is favorable and produces a magnetic moment of 2.00 P-B, which indicates that low temperature ferromagnetism materials could be made by intro- ducing V atoms in Na0.5Bi0.5TiO3. This may be a new way to produce low temperature multiferroic materials.

LOAD FLOW CALCULATION FOR FLEXIBLE AC TRANSMISSION SYSTEMS

In this paper, a synthetic mathematical model of load flow for flexible AC transmission systems (FACTS) with unified power flow controller (UPFC) is presented based on the analysis of basic principle and operation state of UPFC. The model can use the fast P Q decoupled load flow method. Examples of test systems show that the proposed model and method have good convergence. An effective tool is provided by the load flow computer program to analyze the load flow and initial valve calculation of the dynamic state of FACTS.

EXPERT SYSTEM AND ITS APPLICATION IN THE SELECTION OF PIT RETAINING STRUCTURES

This paper describes the development of an expert system(ES) on earth retaining structures for the selection and design.The ES retaining is an interactive menudriven system and consists of two main parts—the selection part,selectwall and the design part.Selectwall is developed using the knowledge base and it makes a choice of the most appropriate retaining structure.The design part is developed by three independent subprograms which perform detailed design including strength,deformation,stability of the retaining structure.The calculation results are illustrated by plotting the diagram.Using this program,the design procedure of the retaining structure can be performed automatically.

APPLICATION OF WYATT-WHITE METHOD TO CALCULATING INTRINSIC RATES OF INCREASE FOR HYMENOPTEROUS PARASITOIDS

The method developed by Wyatt and White (1977) was applied to calculate the intrinsic rates of increase for parasitoids based on 23 fecundity data sets from the literature. The studies showed that there existed the linear relationship between the accurate values of rm and In f (Md) / d or In (A/d/2) / d, that is, 1) rm= 0.845 In (Md) / d or 2) rm= 0.880 In (Md/ 2) / d. Where d is the prereproductive time, Md is the number of female offspring produced per original female from the first to the dthday of reproduction, and Md/2 is the number of female offspring produced per original female from the first to the (d/ 2) th day of reproduction. These equations can provide the accurate estimates of rm for parasitoids in this study. The approach is advantageous because it does not require the construction of detailed fecundity tables for estimating parasitoid rates of increase. Of course, whether these equations are appropriate for the other taxa will need to be further studied.

Stable structures and properties of Ru_(2)Al_(5)

Novel ordered intermetallic compounds have stimulated much interest.Ru–Al alloys are a prominent class of hightemperature structural materials,but the experimentally reported crystal structure of the intermetallic Ru_(2)Al_(5) phase remains elusive and debatable.To resolve this controversy,we extensively explored the crystal structures of Ru_(2)Al_(5) using first-principles calculations combined with crystal structure prediction technique.Among the calculated x-ray diffraction patterns and lattice parameters of five candidate Ru2Al5structures,those of the orthorhombic Pmmn structure best aligned with recent experimental results.The structural stabilities of the five Ru_(2)Al_(5)structures were confirmed through formation energy,elastic constants,and phonon spectrum calculations.We also comprehensively analyzed the mechanical and electronic properties of the five candidates.This work can guide the exploration of novel ordered intermetallic compounds in Ru–Al alloys.

Risk factors for biometry prediction error by Barrett Universal II intraocular lens formula in Chinese patients

AIM:To investigate the influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Universal II(BUII)IOL formula for calculation.METHODS:The prospective study included patients who had undergone cataract surgery performed by a single surgeon from June 2020 to April 2022.The collected data included the best-corrected visual acuity(BCVA),corneal curvature,preoperative and postoperative central anterior chamber depths(ACD),axial length(AXL),IOL power,and refractive error.BUII formula was used to calculate the IOL power.The mean absolute error(MAE)was calculated,and all the participants were divided into two groups accordingly.Independent t-tests were applied to compare the variables between groups.Logistic regression analysis was used to analyze the influence of age,AXL,corneal curvature,and preoperative and postoperative ACD on MAE.RESULTS:A total of 261 patients were enrolled.The 243(93.1%)and 18(6.9%)had postoperative MAE<1 and>1 D,respectively.The number of females was higher in patients with MAE>1 D(χ^(2)=3.833,P=0.039).The postoperative BCVA(logMAR)of patients with MAE>1 D was significantly worse(t=-2.448;P=0.025).After adjusting for gender in the logistic model,the risk of postoperative refractive errors was higher in patients with a shallow postoperative anterior chamber[odds ratio=0.346;95% confidence interval(CI):0.164,0.730,P=0.005].CONCLUSION:Risk factors for biometry prediction error after cataract surgery include the patient’s sex and postoperative ACD.Patients with a shallow postoperative anterior chamber are prone to have refractive errors.

Integration system research and development for three-dimensional laser scanning information visualization in goaf

An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.

Laser Linewidth and Spectral Resolution in Infrared Scanning Sum Frequency Generation Vibrational Spectroscopy System

Sum frequency generation vibrational spectroscopy （SFG-VS） is a robust technique for inter- facial investigation at molecular level. The performance of SFG-VS mostly depends on the spectral resolution of the SFG system. In this research, a simplified function was deduced to calculate the spectral resolution of picosecond SFG system and the lineshape of SFG spectra based on the Guassian shaped functions of IR beam and visible beam. The function indicates that the lineshpe of SFG spectra from nonresonant samples can be calculated by the Guassian widths of both IR beam and visible beam. And the Voigt lineshape of SFG spectra from vibrational resonant samples can be calculated by the Homogeneous broadening （Lorentzian width） and Inhomogeneous broadening （Guassian width） of vibrational modes, as well as the Guassian widths of both IR beam and visible beam. Such functions were also applied to verify the spectral resolution of the polarization-resolved and frequency-resolved picosecond SFG-VS system which was developed by our group recently. It is shown that the linewidths of IR beams that generated from current laser system are about 1.5 cm-1. The calculated spectral resolution of current picosecond IR scanning SFG-VS system is about 4.6 cm-1, which is consist with he spctral resolution shown in the spectra of cholesterol monolayer （3.5-5 cm-1）.