Weather forecasts from numerical weather prediction models play a central role in solar energy forecasting,where a cascade of physics-based models is used in a model chain approach to convert forecasts of solar irradi...Weather forecasts from numerical weather prediction models play a central role in solar energy forecasting,where a cascade of physics-based models is used in a model chain approach to convert forecasts of solar irradiance to solar power production.Ensemble simulations from such weather models aim to quantify uncertainty in the future development of the weather,and can be used to propagate this uncertainty through the model chain to generate probabilistic solar energy predictions.However,ensemble prediction systems are known to exhibit systematic errors,and thus require post-processing to obtain accurate and reliable probabilistic forecasts.The overarching aim of our study is to systematically evaluate different strategies to apply post-processing in model chain approaches with a specific focus on solar energy:not applying any post-processing at all;post-processing only the irradiance predictions before the conversion;post-processing only the solar power predictions obtained from the model chain;or applying post-processing in both steps.In a case study based on a benchmark dataset for the Jacumba solar plant in the U.S.,we develop statistical and machine learning methods for postprocessing ensemble predictions of global horizontal irradiance(GHI)and solar power generation.Further,we propose a neural-network-based model for direct solar power forecasting that bypasses the model chain.Our results indicate that postprocessing substantially improves the solar power generation forecasts,in particular when post-processing is applied to the power predictions.The machine learning methods for post-processing slightly outperform the statistical methods,and the direct forecasting approach performs comparably to the post-processing strategies.展开更多
In the present computational fluid dynamics （CFD） community, post-processing is regarded as a procedure to view parameter distribution, detect characteristic structure and reveal physical mechanism of fluid flow bas...In the present computational fluid dynamics （CFD） community, post-processing is regarded as a procedure to view parameter distribution, detect characteristic structure and reveal physical mechanism of fluid flow based on computational or experimental results. Field plots by contours, iso-surfaces, streamlines, vectors and others are traditional post-processing techniques. While the shock wave, as one important and critical flow structure in many aerodynamic problems, can hardly be detected or distinguished in a direct way using these traditional methods, due to possible confusions with other similar discontinuous flow structures like slip line, contact discontinuity, etc. Therefore, method for automatic detection of shock wave in post-processing is of great importance for both academic research and engineering applications. In this paper, the current status of methodologies developed for shock wave detection and implementations in post-processing platform are reviewed, as well as discussions on advantages and limitations of the existing methods and proposals for further studies of shock wave detection method. We also develop an advanced post-processing software, with improved shock detection.展开更多
Quantum random number generators adopting single negligible dead time of avalanche photodiodes （APDs） photon detection have been restricted due to the non- We propose a new approach based on an APD array to improve...Quantum random number generators adopting single negligible dead time of avalanche photodiodes （APDs） photon detection have been restricted due to the non- We propose a new approach based on an APD array to improve the generation rate of random numbers significantly. This method compares the detectors＇ responses to consecutive optical pulses and generates the random sequence. We implement a demonstration experiment to show its simplicity, compactness and scalability. The generated numbers are proved to be unbiased, post-processing free, ready to use, and their randomness is verified by using the national institute of standard technology statistical test suite. The random bit generation efficiency is as high as 32.8% and the potential generation rate adopting the 32× 32 APD array is up to tens of Gbits/s.展开更多
In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflec...In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting.展开更多
The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for coll...The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for collecting data is not sufficient because of their limited coverage and expensive costs for installation and maintenance. Application of the Global Positioning Systems (GPS) in travel time and delay data collections is proven to be efficient in terms of accuracy, level of details for the data and required data collection of man-power. While data collection automation is improved by the GPS technique, human errors can easily find their way through the post-processing phase, and therefore data post-processing remains a challenge especially in case of big projects with high amount of data. This paper introduces a stand-alone post-processing tool called GPS Calculator, which provides an easy-to-use environment to carry out data post-processing. This is a Visual Basic application that processes the data files obtained in the field and integrates them into Geographic Information Systems (GIS) for analysis and representation. The results show that this tool obtains similar results to the currently used data post-processing method, reduces the post-processing effort, and also eliminates the need for the second person during the data collection.展开更多
When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive ...When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive numerical data may probably exceed the capacity of available memory,resulting in failure of rendering.Based on the out-of-core technique,this paper proposes a method to effectively utilize external storage and reduce memory usage dramatically,so as to solve the problem of insufficient memory for massive data rendering on general personal computers.Based on this method,a new postprocessor is developed.It is capable to illustrate filling and solidification processes of casting,as well as thermal stess.The new post-processor also provides fast interaction to simulation results.Theoretical analysis as well as several practical examples prove that the memory usage and loading time of the post-processor are independent of the size of the relevant files,but the proportion of the number of cells on surface.Meanwhile,the speed of rendering and fetching of value from the mouse is appreciable,and the demands of real-time and interaction are satisfied.展开更多
To improve the ability of detecting underwater targets under strong wideband interference environment,an efficient method of line spectrum extraction is proposed,which fully utilizes the feature of the target spectrum...To improve the ability of detecting underwater targets under strong wideband interference environment,an efficient method of line spectrum extraction is proposed,which fully utilizes the feature of the target spectrum that the high intense and stable line spectrum is superimposed on the wide continuous spectrum.This method modifies the traditional beam forming algorithm by calculating and fusing the beam forming results at multi-frequency band and multi-azimuth interval,showing an excellent way to extract the line spectrum when the interference and the target are not in the same azimuth interval simultaneously.Statistical efficiency of the estimated azimuth variance and corresponding power of the line spectrum band depends on the line spectra ratio(LSR)of the line spectrum.The change laws of the output signal to noise ratio(SNR)with the LSR,the input SNR,the integration time and the filtering bandwidth of different algorithms bring the selection principle of the critical LSR.As the basis,the detection gain of wideband energy integration and the narrowband line spectrum algorithm are theoretically analyzed.The simulation detection gain demonstrates a good match with the theoretical model.The application conditions of all methods are verified by the receiver operating characteristic(ROC)curve and experimental data from Qiandao Lake.In fact,combining the two methods for target detection reduces the missed detection rate.The proposed post-processing method in2-dimension with the Kalman filter in the time dimension and the background equalization algorithm in the azimuth dimension makes use of the strong correlation between adjacent frames,could further remove background fluctuation and improve the display effect.展开更多
This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids...This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave; the timbre tends to sound much brighter, thicker and more beautiful.展开更多
Low contrast of Magnetic Resonance(MR)images limits the visibility of subtle structures and adversely affects the outcome of both subjective and automated diagnosis.State-of-the-art contrast boosting techniques intole...Low contrast of Magnetic Resonance(MR)images limits the visibility of subtle structures and adversely affects the outcome of both subjective and automated diagnosis.State-of-the-art contrast boosting techniques intolerably alter inherent features of MR images.Drastic changes in brightness features,induced by post-processing are not appreciated in medical imaging as the grey level values have certain diagnostic meanings.To overcome these issues this paper proposes an algorithm that enhance the contrast of MR images while preserving the underlying features as well.This method termed as Power-law and Logarithmic Modification-based Histogram Equalization(PLMHE)partitions the histogram of the image into two sub histograms after a power-law transformation and a log compression.After a modification intended for improving the dispersion of the sub-histograms and subsequent normalization,cumulative histograms are computed.Enhanced grey level values are computed from the resultant cumulative histograms.The performance of the PLMHE algorithm is comparedwith traditional histogram equalization based algorithms and it has been observed from the results that PLMHE can boost the image contrast without causing dynamic range compression,a significant change in mean brightness,and contrast-overshoot.展开更多
In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produce...In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produced by wall holes and the loss of precision induced by using differential method to derive strains, the displacement-based elements cannot always present accuracy enough for design. In this paper, the hybrid post-processing procedure based on the Hellinger-Reissner variational principle is used for improving the stress precision of two quadrilateral plane elements. In order to find the best stress field, three different forms are assumed for the displacement-based plane elements and with drilling DOF. Numerical results show that by using the proposed method, the accuracy of stress solutions of these two displacement-based plane elements can be improved.展开更多
Laser additive manufacturing(LAM)of titanium(Ti)alloys has emerged as a transformative technology with vast potential across multiple industries.To recap the state of the art,Ti alloys processed by two essential LAM t...Laser additive manufacturing(LAM)of titanium(Ti)alloys has emerged as a transformative technology with vast potential across multiple industries.To recap the state of the art,Ti alloys processed by two essential LAM techniques(i.e.,laser powder bed fusion and laser-directed energy deposition)will be reviewed,covering the aspects of processes,materials and post-processing.The impacts of process parameters and strategies for optimizing parameters will be elucidated.Various types of Ti alloys processed by LAM,includingα-Ti,(α+β)-Ti,andβ-Ti alloys,will be overviewed in terms of micro structures and benchmarking properties.Furthermore,the post-processing methods for improving the performance of L AM-processed Ti alloys,including conventional and novel heat treatment,hot isostatic pressing,and surface processing(e.g.,ultrasonic and laser shot peening),will be systematically reviewed and discussed.The review summarizes the process windows,properties,and performance envelopes and benchmarks the research achievements in LAM of Ti alloys.The outlooks of further trends in LAM of Ti alloys are also highlighted at the end of the review.This comprehensive review could serve as a valuable resource for researchers and practitioners,promoting further advancements in LAM-built Ti alloys and their applications.展开更多
During the exploitation of sandstone gas reservoirs,natural fractures near the wellbore affect water infiltration and pore evolution;however,the impact mechanisms of these fractures remain unclear.This study utilized ...During the exploitation of sandstone gas reservoirs,natural fractures near the wellbore affect water infiltration and pore evolution;however,the impact mechanisms of these fractures remain unclear.This study utilized real-time nuclear magnetic resonance(RT-NMR)technology to investigate the influence of near-wellbore fracture angle(a)at 0°,15°,30°,and 45°on water infiltration,migration patterns,and pore evolution mechanisms during water injection.Throughout the experiments,T_(2)curves and magnetic resonance imaging(MRI)were monito red in real time during the water injection process.The pore evolution and water infiltration were translated by the evolution of T_(2)curves and MRI.The results show that increasing injection pressure(P_(inj))transforms adsorption pores into seepage pores,leading to enhanced pore damage.Pore damage predominantly occurs during the rapid pressurization stage and is concentrated around the near-wellbore fracture.The maximum infiltration area and rate were observed at α=0°,while the minimum values occurred at α=45°,which can be attributed to the significant influence of a on water infiltration and migration pathways.The increasing inclination of the infiltration front with a is attributed to the fact that the rate of water infiltration along the fracture wall is always higher than that at the fracture tip.In field fracturing,it is recommended to adjust the perforation direction to align with the natural fracture orientation and optimize pressurization strategies by reducing the slow pressurization duration while extending the rapid pressurization stage.These findings can provide important guidance for setting fracturing sections and optimizing injection parameters in sandstone gas reservoir exploitation.展开更多
To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and ev...To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and even among those who undergo this procedure,the risk of recurrence within three years remains alarmingly high,reach-ing up to 70%[2].Due to the lack of specific clinical manifes-tations of pancreatic cancer,most cases have metastasized or in-vaded the major vessels around the pancreas at the time of initial diagnosis,resulting in a low surgical resection rate.Even patients who undergo surgical resection often face a poor prognosis[3].In recent years,neoadjuvant chemotherapy using agents such as gemcitabine,5-fluorouracil,albumin-bound paclitaxel,modified fluorouracil/leucovorin plus irinotecan,and oxaliplatin(mFOLFIRI-NOX),targeted therapies addressing molecular subtypes of pan-creatic cancer,and immunotherapies targeting PD-1 and PD-L1 have shown efficacy in improving the overall prognosis of patients with pancreatic cancer,although the impact remains modest[4,5].Therefore,novel therapeutic strategies and prognostic evaluation systems are urgently needed to enhance the survival of patients with pancreatic cancer.展开更多
Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage ...Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage in structures such as dams,tunnels,canals,and pipelines.By utilizing a few easily measurable parameters,engineers can employ these formulas to generate preliminary leakage rate estimates before proceeding with more detailed analyses.In this study,a physical model was developed,and a series of experiments were conducted,considering variables such as inflow rate,materials constituting the unsaturated medium,and variations in infiltration trench depth and width.As a result,a novel artificial recharge method was introduced,and an empirical equation,Q_(out)=0.0066×D_(50)^(0.64)×L×P^(0.36),was proposed to estimate the infiltration capacity of the trench.This equation incorporates factors such as the wetted perimeter,mean soil particle diameter,trench length,and a coefficient.A comparative analysis between the observed data from nine Iranian earthen canals and the values calculated using the proposed equation revealed an average relative error of 15%between the two datasets.In addition,the Pearson correlation coefficient was determined to be 0.981 and the Root Mean Square Error(RMSE)was 0.381,demonstrating the strong predictive performance of the equation.The parameters considered in the proposed equation allow for its application across diverse regions.Given its accurate performance,this equation provides a reliable initial estimate of the leakage rate,thereby helping to reduce costs and save time.展开更多
AIM:To investigate cuproptosis-related molecular and immune infiltration in age-related macular degeneration(AMD)development and establish a predictive model.METHODS:The expression profiles of cuproptosisrelated genes...AIM:To investigate cuproptosis-related molecular and immune infiltration in age-related macular degeneration(AMD)development and establish a predictive model.METHODS:The expression profiles of cuproptosisrelated genes and immune signature in AMD based on the microarray dataset GSE29801 were analyzed.A total of 142 AMD samples were used to identify the cuproptosisrelated differentially expressed genes(Cu-DEGs),together with the immune cell infiltration.To further refine the list of potential genes for AMD diagnosis,three machine learning techniques were used,and an external dataset were applied for confirming the accuracy of the predictive performance.Reverse transcription polymerase chain reaction(RT-PCR)were also performed to examine the level of mRNA of hub genes.The activated immune responses and Cu-DEGs were assessed between AMD and controls.RESULTS:Six genes,including ATP7A,DBT,VEGFA,UBE2D3,CP,SLC31A1,were screened as cuproptosissignature in AMD via three machine learning methods.Next,SLC31A1 and VEGFA was selected as hub genes by performance evaluation in an external dataset GSE160011,further analysis showed that SLC31A1 and VEGFA were associated with pathways related to immune signaling and immune function,which were then observed in relation to infiltrating immune cells.Finally,the mRNA expression levels of SLC31A1 and VEGFA were significantly higher in laser induced choroidal neovascularization(CNV)group than in control group detected by RT-PCR.CONCLUSION:In this study,the possible relationship between cuproptosis and AMD is expounded systematically.A predictive model is developed to assess the risk of cuproptosis-related genes and their clinical prognostic value in AMD patients.展开更多
With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mecha...With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mechanical properties of PDC incurs prohibitively elevated costs and stringent technological challenges.Here,we present a two-stage high-pressure infiltration(HPI)methodology involving cobalt removal pretreatment followed by lubricant infiltration.The successful infiltration of lubricants into diamond micropores has been systematically verified,and the effects of lubricant phase composition,infiltration pressure,and temperature on infiltration depth have been thoroughly investigated.Fractal dimension analysis characterizes the pore structure of cobalt-removed diamonds,revealing a strong correlation between the fractal dimension and friction coefficient reduction.Tribological testing confirms the formation of lubricating films at friction interfaces,achieving a 71.5%reduction in the coefficient of friction for lubricant-containing diamond materials.This straightforward strategy opens a gate to developing the next generation of self-lubricating diamond materials.展开更多
BACKGROUND Shwachman-Diamond syndrome(SDS)is a rare genetic disorder that affects multiple organs,primarily the liver.Most patients are diagnosed during infancy or early childhood.As they grow older,the majority of af...BACKGROUND Shwachman-Diamond syndrome(SDS)is a rare genetic disorder that affects multiple organs,primarily the liver.Most patients are diagnosed during infancy or early childhood.As they grow older,the majority of affected children may experience spontaneous remission,and cases of cirrhosis in adults are rarely reported.CASE SUMMARY A 36-year-old male patient presented with massive ascites.Laboratory tests revealed pancytopenia and a serum-ascites albumin gradient greater than 1.1 g/dL.An abdominal computed tomography scan demonstrated cirrhosis,splenomegaly,pancreatic fat infiltration,and a substantial accumulation of peritoneal fluid.Gastroscopy identified esophageal varices.Liver stiffness measurement indicated a value of 32.7 kPa.Based on the results of auxiliary examinations,common causes of cirrhosis were excluded,and a mutation in the Shwachman-Bodian-Diamond syndrome gene was ultimately identified through whole-exome sequencing.The patient was diagnosed with cirrhosis secondary to SDS.Following the correction of hypoalbuminemia and administration of diuretics,the patient's ascites resolved.CONCLUSION Patients with liver cirrhosis who also exhibit pancreatic fat infiltration and pancytopenia necessitate further exon testing to exclude the possibility of SDS.展开更多
BACKGROUND Colorectal cancer(CRC)remains a major global health burden due to its high incidence and mortality,with treatment efficacy often hindered by tumor hetero-geneity,drug resistance,and a complex tumor microenv...BACKGROUND Colorectal cancer(CRC)remains a major global health burden due to its high incidence and mortality,with treatment efficacy often hindered by tumor hetero-geneity,drug resistance,and a complex tumor microenvironment(TME).Lactate metabolism plays a pivotal role in reshaping the TME,promoting immune eva-sion and epithelial-mesenchymal transition,making it a promising target for novel therapeutic strategies and prognostic modeling in CRC.AIM To offer an in-depth analysis of the role of lactate metabolism in CRC,high-lighting its significance in the TME and therapeutic response.METHODS Utilizing single-cell and transcriptomic data from the Gene Expression Omnibus and The Cancer Genome Atlas,we identified key lactate metabolic activities,particularly in the monocyte/macrophage subpopulation.RESULTS Seven lactate metabolism-associated genes were significantly linked to CRC prognosis and used to construct a predictive model.This model accurately forecasts patient outcomes and reveals notable distinct patterns of immune infiltration and transcriptomic profiles mutation profiles between high-and low-risk groups.High-risk patients demonstrated elevated immune cell infiltration,increased mutation frequencies,and heightened sensitivity to specific drugs(AZD6482,tozasertib,and SB216763),providing a foundation for personalized treatment approaches.Additionally,a nomogram integrating clinical and metabolic data effectively predicted 1-,3-,and 5-year survival rates.CONCLUSION This report underscored the pivotal mechanism of lactate metabolism in CRC prognosis and suggest novel avenues for therapeutic intervention.展开更多
The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the act...The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the actual porosity and pore size of the prepared P model for each pore size are greater than the designed values.The addition of Ca changes the second phase of the alloy from Mg_(2)Sn to CaMgSn and refines its microstructure.The compressive yield strength and compressive modulus of the Mg−1Zn−1Sn−0.2Ca alloy scaffold reach 32.61 MPa and 0.23 GPa,respectively.The corrosion current density is measured at 14.64μA/cm^(2),with an instantaneous corrosion rate of 0.335 mm/a.Both scaffolds exhibit excellent biocompatibility and no cytotoxicity.Additionally,the antibacterial effects of both alloys on E.coli are greater than 97.81%.These results indicate that Mg alloy scaffolds have great potential for clinical applications.展开更多
The rapid advancement of single-cell sequencing(SCS)technology has provided new insights into the relationship between inflammatory bowel disease(IBD)and colorectal cancer(CRC).This technique allows for detailed cellu...The rapid advancement of single-cell sequencing(SCS)technology has provided new insights into the relationship between inflammatory bowel disease(IBD)and colorectal cancer(CRC).This technique allows for detailed cellular analysis,enabling researchers to uncover the infiltration patterns of immune cells within the gut microenvironment and their roles in disease progression.This review summarizes significant research findings on the interplay between IBD and CRC,the characteristics of immune cell infiltration,and potential therapeutic targets identified through SCS.The aim is to offer references for future clinical studies and treatment strategies in this field.展开更多
基金the Young Investigator Group“Artificial Intelligence for Probabilistic Weather Forecasting”funded by the Vector Stiftungfunding from the Federal Ministry of Education and Research(BMBF)and the Baden-Württemberg Ministry of Science as part of the Excellence Strategy of the German Federal and State Governments。
文摘Weather forecasts from numerical weather prediction models play a central role in solar energy forecasting,where a cascade of physics-based models is used in a model chain approach to convert forecasts of solar irradiance to solar power production.Ensemble simulations from such weather models aim to quantify uncertainty in the future development of the weather,and can be used to propagate this uncertainty through the model chain to generate probabilistic solar energy predictions.However,ensemble prediction systems are known to exhibit systematic errors,and thus require post-processing to obtain accurate and reliable probabilistic forecasts.The overarching aim of our study is to systematically evaluate different strategies to apply post-processing in model chain approaches with a specific focus on solar energy:not applying any post-processing at all;post-processing only the irradiance predictions before the conversion;post-processing only the solar power predictions obtained from the model chain;or applying post-processing in both steps.In a case study based on a benchmark dataset for the Jacumba solar plant in the U.S.,we develop statistical and machine learning methods for postprocessing ensemble predictions of global horizontal irradiance(GHI)and solar power generation.Further,we propose a neural-network-based model for direct solar power forecasting that bypasses the model chain.Our results indicate that postprocessing substantially improves the solar power generation forecasts,in particular when post-processing is applied to the power predictions.The machine learning methods for post-processing slightly outperform the statistical methods,and the direct forecasting approach performs comparably to the post-processing strategies.
文摘In the present computational fluid dynamics （CFD） community, post-processing is regarded as a procedure to view parameter distribution, detect characteristic structure and reveal physical mechanism of fluid flow based on computational or experimental results. Field plots by contours, iso-surfaces, streamlines, vectors and others are traditional post-processing techniques. While the shock wave, as one important and critical flow structure in many aerodynamic problems, can hardly be detected or distinguished in a direct way using these traditional methods, due to possible confusions with other similar discontinuous flow structures like slip line, contact discontinuity, etc. Therefore, method for automatic detection of shock wave in post-processing is of great importance for both academic research and engineering applications. In this paper, the current status of methodologies developed for shock wave detection and implementations in post-processing platform are reviewed, as well as discussions on advantages and limitations of the existing methods and proposals for further studies of shock wave detection method. We also develop an advanced post-processing software, with improved shock detection.
基金Supported by the Chinese Academy of Sciences Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics,Shanghai Branch,University of Science and Technology of Chinathe National Natural Science Foundation of China under Grant No 11405172
文摘Quantum random number generators adopting single negligible dead time of avalanche photodiodes （APDs） photon detection have been restricted due to the non- We propose a new approach based on an APD array to improve the generation rate of random numbers significantly. This method compares the detectors＇ responses to consecutive optical pulses and generates the random sequence. We implement a demonstration experiment to show its simplicity, compactness and scalability. The generated numbers are proved to be unbiased, post-processing free, ready to use, and their randomness is verified by using the national institute of standard technology statistical test suite. The random bit generation efficiency is as high as 32.8% and the potential generation rate adopting the 32× 32 APD array is up to tens of Gbits/s.
基金Projects 50221402, 50490271 and 50025413 supported by the National Natural Science Foundation of Chinathe National Basic Research Program of China (2009CB219603, 2009 CB724601, 2006CB202209 and 2005CB221500)+1 种基金the Key Project of the Ministry of Education (306002)the Program for Changjiang Scholars and Innovative Research Teams in Universities of MOE (IRT0408)
文摘In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting.
文摘The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for collecting data is not sufficient because of their limited coverage and expensive costs for installation and maintenance. Application of the Global Positioning Systems (GPS) in travel time and delay data collections is proven to be efficient in terms of accuracy, level of details for the data and required data collection of man-power. While data collection automation is improved by the GPS technique, human errors can easily find their way through the post-processing phase, and therefore data post-processing remains a challenge especially in case of big projects with high amount of data. This paper introduces a stand-alone post-processing tool called GPS Calculator, which provides an easy-to-use environment to carry out data post-processing. This is a Visual Basic application that processes the data files obtained in the field and integrates them into Geographic Information Systems (GIS) for analysis and representation. The results show that this tool obtains similar results to the currently used data post-processing method, reduces the post-processing effort, and also eliminates the need for the second person during the data collection.
基金supported by the New Century Excellent Talents in University(NCET-09-0396)the National Science&Technology Key Projects of Numerical Control(2012ZX04014-031)+1 种基金the Natural Science Foundation of Hubei Province(2011CDB279)the Foundation for Innovative Research Groups of the Natural Science Foundation of Hubei Province,China(2010CDA067)
文摘When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive numerical data may probably exceed the capacity of available memory,resulting in failure of rendering.Based on the out-of-core technique,this paper proposes a method to effectively utilize external storage and reduce memory usage dramatically,so as to solve the problem of insufficient memory for massive data rendering on general personal computers.Based on this method,a new postprocessor is developed.It is capable to illustrate filling and solidification processes of casting,as well as thermal stess.The new post-processor also provides fast interaction to simulation results.Theoretical analysis as well as several practical examples prove that the memory usage and loading time of the post-processor are independent of the size of the relevant files,but the proportion of the number of cells on surface.Meanwhile,the speed of rendering and fetching of value from the mouse is appreciable,and the demands of real-time and interaction are satisfied.
基金supported by the National Natural Science Foundation of China(51875535)the Natural Science Foundation for Young Scientists of Shanxi Province(201701D221017,201901D211242)。
文摘To improve the ability of detecting underwater targets under strong wideband interference environment,an efficient method of line spectrum extraction is proposed,which fully utilizes the feature of the target spectrum that the high intense and stable line spectrum is superimposed on the wide continuous spectrum.This method modifies the traditional beam forming algorithm by calculating and fusing the beam forming results at multi-frequency band and multi-azimuth interval,showing an excellent way to extract the line spectrum when the interference and the target are not in the same azimuth interval simultaneously.Statistical efficiency of the estimated azimuth variance and corresponding power of the line spectrum band depends on the line spectra ratio(LSR)of the line spectrum.The change laws of the output signal to noise ratio(SNR)with the LSR,the input SNR,the integration time and the filtering bandwidth of different algorithms bring the selection principle of the critical LSR.As the basis,the detection gain of wideband energy integration and the narrowband line spectrum algorithm are theoretically analyzed.The simulation detection gain demonstrates a good match with the theoretical model.The application conditions of all methods are verified by the receiver operating characteristic(ROC)curve and experimental data from Qiandao Lake.In fact,combining the two methods for target detection reduces the missed detection rate.The proposed post-processing method in2-dimension with the Kalman filter in the time dimension and the background equalization algorithm in the azimuth dimension makes use of the strong correlation between adjacent frames,could further remove background fluctuation and improve the display effect.
文摘This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave; the timbre tends to sound much brighter, thicker and more beautiful.
基金This work was supported by Taif university Researchers Supporting Project Number(TURSP-2020/114),Taif University,Taif,Saudi Arabia.
文摘Low contrast of Magnetic Resonance(MR)images limits the visibility of subtle structures and adversely affects the outcome of both subjective and automated diagnosis.State-of-the-art contrast boosting techniques intolerably alter inherent features of MR images.Drastic changes in brightness features,induced by post-processing are not appreciated in medical imaging as the grey level values have certain diagnostic meanings.To overcome these issues this paper proposes an algorithm that enhance the contrast of MR images while preserving the underlying features as well.This method termed as Power-law and Logarithmic Modification-based Histogram Equalization(PLMHE)partitions the histogram of the image into two sub histograms after a power-law transformation and a log compression.After a modification intended for improving the dispersion of the sub-histograms and subsequent normalization,cumulative histograms are computed.Enhanced grey level values are computed from the resultant cumulative histograms.The performance of the PLMHE algorithm is comparedwith traditional histogram equalization based algorithms and it has been observed from the results that PLMHE can boost the image contrast without causing dynamic range compression,a significant change in mean brightness,and contrast-overshoot.
文摘In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produced by wall holes and the loss of precision induced by using differential method to derive strains, the displacement-based elements cannot always present accuracy enough for design. In this paper, the hybrid post-processing procedure based on the Hellinger-Reissner variational principle is used for improving the stress precision of two quadrilateral plane elements. In order to find the best stress field, three different forms are assumed for the displacement-based plane elements and with drilling DOF. Numerical results show that by using the proposed method, the accuracy of stress solutions of these two displacement-based plane elements can be improved.
基金financially supported by the 2022 MTC Young Individual Research Grants under Singapore Research,Innovation and Enterprise(RIE)2025 Plan(No.M22K3c0097)the Natural Science Foundation of US(No.DMR-2104933)the sponsorship of the China Scholarship Council(No.202106130051)。
文摘Laser additive manufacturing(LAM)of titanium(Ti)alloys has emerged as a transformative technology with vast potential across multiple industries.To recap the state of the art,Ti alloys processed by two essential LAM techniques(i.e.,laser powder bed fusion and laser-directed energy deposition)will be reviewed,covering the aspects of processes,materials and post-processing.The impacts of process parameters and strategies for optimizing parameters will be elucidated.Various types of Ti alloys processed by LAM,includingα-Ti,(α+β)-Ti,andβ-Ti alloys,will be overviewed in terms of micro structures and benchmarking properties.Furthermore,the post-processing methods for improving the performance of L AM-processed Ti alloys,including conventional and novel heat treatment,hot isostatic pressing,and surface processing(e.g.,ultrasonic and laser shot peening),will be systematically reviewed and discussed.The review summarizes the process windows,properties,and performance envelopes and benchmarks the research achievements in LAM of Ti alloys.The outlooks of further trends in LAM of Ti alloys are also highlighted at the end of the review.This comprehensive review could serve as a valuable resource for researchers and practitioners,promoting further advancements in LAM-built Ti alloys and their applications.
基金supported by National Natural Science Foundation of China(Nos.52364004,52464005)The Youth Talent Growth Project of Guizhou Provincial Department of Education(No.Qian Jiao Ji[2024]18)+3 种基金Postgraduate Research Fund of Guizhou Province in 2024(No.2024YJSKYJJ067)Basic Research Project of Guizhou University(No.[2023]40)Guizhou Provincial Basic Research Program(Natural Science)(No.Qian Ke He Ji Chu-ZK[2024]Yi Ban011)Research Fund for Talents of Guizhou University(No.Gui Da Ren Ji He Zi(2023)24)。
文摘During the exploitation of sandstone gas reservoirs,natural fractures near the wellbore affect water infiltration and pore evolution;however,the impact mechanisms of these fractures remain unclear.This study utilized real-time nuclear magnetic resonance(RT-NMR)technology to investigate the influence of near-wellbore fracture angle(a)at 0°,15°,30°,and 45°on water infiltration,migration patterns,and pore evolution mechanisms during water injection.Throughout the experiments,T_(2)curves and magnetic resonance imaging(MRI)were monito red in real time during the water injection process.The pore evolution and water infiltration were translated by the evolution of T_(2)curves and MRI.The results show that increasing injection pressure(P_(inj))transforms adsorption pores into seepage pores,leading to enhanced pore damage.Pore damage predominantly occurs during the rapid pressurization stage and is concentrated around the near-wellbore fracture.The maximum infiltration area and rate were observed at α=0°,while the minimum values occurred at α=45°,which can be attributed to the significant influence of a on water infiltration and migration pathways.The increasing inclination of the infiltration front with a is attributed to the fact that the rate of water infiltration along the fracture wall is always higher than that at the fracture tip.In field fracturing,it is recommended to adjust the perforation direction to align with the natural fracture orientation and optimize pressurization strategies by reducing the slow pressurization duration while extending the rapid pressurization stage.These findings can provide important guidance for setting fracturing sections and optimizing injection parameters in sandstone gas reservoir exploitation.
文摘To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and even among those who undergo this procedure,the risk of recurrence within three years remains alarmingly high,reach-ing up to 70%[2].Due to the lack of specific clinical manifes-tations of pancreatic cancer,most cases have metastasized or in-vaded the major vessels around the pancreas at the time of initial diagnosis,resulting in a low surgical resection rate.Even patients who undergo surgical resection often face a poor prognosis[3].In recent years,neoadjuvant chemotherapy using agents such as gemcitabine,5-fluorouracil,albumin-bound paclitaxel,modified fluorouracil/leucovorin plus irinotecan,and oxaliplatin(mFOLFIRI-NOX),targeted therapies addressing molecular subtypes of pan-creatic cancer,and immunotherapies targeting PD-1 and PD-L1 have shown efficacy in improving the overall prognosis of patients with pancreatic cancer,although the impact remains modest[4,5].Therefore,novel therapeutic strategies and prognostic evaluation systems are urgently needed to enhance the survival of patients with pancreatic cancer.
文摘Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage in structures such as dams,tunnels,canals,and pipelines.By utilizing a few easily measurable parameters,engineers can employ these formulas to generate preliminary leakage rate estimates before proceeding with more detailed analyses.In this study,a physical model was developed,and a series of experiments were conducted,considering variables such as inflow rate,materials constituting the unsaturated medium,and variations in infiltration trench depth and width.As a result,a novel artificial recharge method was introduced,and an empirical equation,Q_(out)=0.0066×D_(50)^(0.64)×L×P^(0.36),was proposed to estimate the infiltration capacity of the trench.This equation incorporates factors such as the wetted perimeter,mean soil particle diameter,trench length,and a coefficient.A comparative analysis between the observed data from nine Iranian earthen canals and the values calculated using the proposed equation revealed an average relative error of 15%between the two datasets.In addition,the Pearson correlation coefficient was determined to be 0.981 and the Root Mean Square Error(RMSE)was 0.381,demonstrating the strong predictive performance of the equation.The parameters considered in the proposed equation allow for its application across diverse regions.Given its accurate performance,this equation provides a reliable initial estimate of the leakage rate,thereby helping to reduce costs and save time.
文摘AIM:To investigate cuproptosis-related molecular and immune infiltration in age-related macular degeneration(AMD)development and establish a predictive model.METHODS:The expression profiles of cuproptosisrelated genes and immune signature in AMD based on the microarray dataset GSE29801 were analyzed.A total of 142 AMD samples were used to identify the cuproptosisrelated differentially expressed genes(Cu-DEGs),together with the immune cell infiltration.To further refine the list of potential genes for AMD diagnosis,three machine learning techniques were used,and an external dataset were applied for confirming the accuracy of the predictive performance.Reverse transcription polymerase chain reaction(RT-PCR)were also performed to examine the level of mRNA of hub genes.The activated immune responses and Cu-DEGs were assessed between AMD and controls.RESULTS:Six genes,including ATP7A,DBT,VEGFA,UBE2D3,CP,SLC31A1,were screened as cuproptosissignature in AMD via three machine learning methods.Next,SLC31A1 and VEGFA was selected as hub genes by performance evaluation in an external dataset GSE160011,further analysis showed that SLC31A1 and VEGFA were associated with pathways related to immune signaling and immune function,which were then observed in relation to infiltrating immune cells.Finally,the mRNA expression levels of SLC31A1 and VEGFA were significantly higher in laser induced choroidal neovascularization(CNV)group than in control group detected by RT-PCR.CONCLUSION:In this study,the possible relationship between cuproptosis and AMD is expounded systematically.A predictive model is developed to assess the risk of cuproptosis-related genes and their clinical prognostic value in AMD patients.
基金supported by the National Natural Science Foundation of China(grant number:52203375 and 52073254)。
文摘With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mechanical properties of PDC incurs prohibitively elevated costs and stringent technological challenges.Here,we present a two-stage high-pressure infiltration(HPI)methodology involving cobalt removal pretreatment followed by lubricant infiltration.The successful infiltration of lubricants into diamond micropores has been systematically verified,and the effects of lubricant phase composition,infiltration pressure,and temperature on infiltration depth have been thoroughly investigated.Fractal dimension analysis characterizes the pore structure of cobalt-removed diamonds,revealing a strong correlation between the fractal dimension and friction coefficient reduction.Tribological testing confirms the formation of lubricating films at friction interfaces,achieving a 71.5%reduction in the coefficient of friction for lubricant-containing diamond materials.This straightforward strategy opens a gate to developing the next generation of self-lubricating diamond materials.
文摘BACKGROUND Shwachman-Diamond syndrome(SDS)is a rare genetic disorder that affects multiple organs,primarily the liver.Most patients are diagnosed during infancy or early childhood.As they grow older,the majority of affected children may experience spontaneous remission,and cases of cirrhosis in adults are rarely reported.CASE SUMMARY A 36-year-old male patient presented with massive ascites.Laboratory tests revealed pancytopenia and a serum-ascites albumin gradient greater than 1.1 g/dL.An abdominal computed tomography scan demonstrated cirrhosis,splenomegaly,pancreatic fat infiltration,and a substantial accumulation of peritoneal fluid.Gastroscopy identified esophageal varices.Liver stiffness measurement indicated a value of 32.7 kPa.Based on the results of auxiliary examinations,common causes of cirrhosis were excluded,and a mutation in the Shwachman-Bodian-Diamond syndrome gene was ultimately identified through whole-exome sequencing.The patient was diagnosed with cirrhosis secondary to SDS.Following the correction of hypoalbuminemia and administration of diuretics,the patient's ascites resolved.CONCLUSION Patients with liver cirrhosis who also exhibit pancreatic fat infiltration and pancytopenia necessitate further exon testing to exclude the possibility of SDS.
基金Supported by Henan Province Science and Technology Research Project,No.232102310043Henan Provincial Science and Technology Research and Development Plan Joint Fund,No.222103810047Key Scientific Research Project Plan of Colleges and Universities in Henan Province,No.22A320033.
文摘BACKGROUND Colorectal cancer(CRC)remains a major global health burden due to its high incidence and mortality,with treatment efficacy often hindered by tumor hetero-geneity,drug resistance,and a complex tumor microenvironment(TME).Lactate metabolism plays a pivotal role in reshaping the TME,promoting immune eva-sion and epithelial-mesenchymal transition,making it a promising target for novel therapeutic strategies and prognostic modeling in CRC.AIM To offer an in-depth analysis of the role of lactate metabolism in CRC,high-lighting its significance in the TME and therapeutic response.METHODS Utilizing single-cell and transcriptomic data from the Gene Expression Omnibus and The Cancer Genome Atlas,we identified key lactate metabolic activities,particularly in the monocyte/macrophage subpopulation.RESULTS Seven lactate metabolism-associated genes were significantly linked to CRC prognosis and used to construct a predictive model.This model accurately forecasts patient outcomes and reveals notable distinct patterns of immune infiltration and transcriptomic profiles mutation profiles between high-and low-risk groups.High-risk patients demonstrated elevated immune cell infiltration,increased mutation frequencies,and heightened sensitivity to specific drugs(AZD6482,tozasertib,and SB216763),providing a foundation for personalized treatment approaches.Additionally,a nomogram integrating clinical and metabolic data effectively predicted 1-,3-,and 5-year survival rates.CONCLUSION This report underscored the pivotal mechanism of lactate metabolism in CRC prognosis and suggest novel avenues for therapeutic intervention.
基金the financial support for this work from the National Natural Science Foundation of China(Nos.52171241,52373251,52201301,51801137)Natural Science Foundation of Tianjin City,China(No.22JCQNJC00750)Tianjin University of Technology Graduate Research Innovation Project,China(No.YJ2235)。
文摘The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the actual porosity and pore size of the prepared P model for each pore size are greater than the designed values.The addition of Ca changes the second phase of the alloy from Mg_(2)Sn to CaMgSn and refines its microstructure.The compressive yield strength and compressive modulus of the Mg−1Zn−1Sn−0.2Ca alloy scaffold reach 32.61 MPa and 0.23 GPa,respectively.The corrosion current density is measured at 14.64μA/cm^(2),with an instantaneous corrosion rate of 0.335 mm/a.Both scaffolds exhibit excellent biocompatibility and no cytotoxicity.Additionally,the antibacterial effects of both alloys on E.coli are greater than 97.81%.These results indicate that Mg alloy scaffolds have great potential for clinical applications.
基金Supported by the Shandong Province Medical and Health Science and Technology Development Plan Project,No.202203030713Yantai Science and Technology Program,No.2024YD005,No.2024YD007 and No.2024YD010Science and Technology Program of Yantai Affiliated Hospital of Binzhou Medical University,No.YTFY2022KYQD06。
文摘The rapid advancement of single-cell sequencing(SCS)technology has provided new insights into the relationship between inflammatory bowel disease(IBD)and colorectal cancer(CRC).This technique allows for detailed cellular analysis,enabling researchers to uncover the infiltration patterns of immune cells within the gut microenvironment and their roles in disease progression.This review summarizes significant research findings on the interplay between IBD and CRC,the characteristics of immune cell infiltration,and potential therapeutic targets identified through SCS.The aim is to offer references for future clinical studies and treatment strategies in this field.
