Background and Objective Electromagnetic navigation technology has demonstrated significant potential in enhancing the accuracy and safety of neurosurgical procedures.However,traditional electromagnetic navigation sys...Background and Objective Electromagnetic navigation technology has demonstrated significant potential in enhancing the accuracy and safety of neurosurgical procedures.However,traditional electromagnetic navigation systems face challenges such as high equipment costs,complex operation,bulky size,and insufficient anti-interference performance.To address these limitations,our study developed and validated a novel portable electromagnetic neuronavigation system designed to improve the precision,accessibility,and clinical applicability of electromagnetic navigation technology in cranial surgery.Methods The software and hardware architecture of a portable neural magnetic navigation system was designed.The key technologies of the system were analysed,including electromagnetic positioning algorithms,miniaturized sensor design,optimization of electromagnetic positioning and navigation algorithms,anti-interference signal processing methods,and fast three-dimensional reconstruction algorithms.A prototype was developed,and its accuracy was tested.Finally,a preliminary clinical application evaluation was conducted.Results This study successfully developed a comprehensive portable electromagnetic neuronavigation system capable of achieving preoperative planning,intraoperative real-time positioning and navigation,and postoperative evaluation of navigation outcomes.Through rigorous collaborative testing of the system’s software and hardware,the accuracy of electromagnetic neuronavigation has been validated to meet clinical requirements.Conclusions This study developed a portable neuroelectromagnetic navigation system and validated its effectiveness and safety through rigorous model testing and preliminary clinical applications.The system is characterized by its compact size,high precision,excellent portability,and user-friendly operation,making it highly valuable for promoting navigation technology and advancing the precision and minimally invasive nature of neurosurgical procedures.展开更多
Traditional diagnostic tools for depression,such as the Patient Health Questionnaire-9,are susceptible to subjective bias,increasing the risk of misdiagnosis and emphasizing the critical need for objective biomarkers....Traditional diagnostic tools for depression,such as the Patient Health Questionnaire-9,are susceptible to subjective bias,increasing the risk of misdiagnosis and emphasizing the critical need for objective biomarkers.This minireview evaluates the emerging role of portable electroencephalography(EEG)as a cost-effective,accessible solution for early depression detection.By synthesizing findings from 45 studies(selected from 764 screened articles),we highlight EEG’s capacity to identify aberrant neural oscillations associated with core depressive symptoms,including anhedonia,excessive guilt,and persistent low mood.Advances in portable systems demonstrate promising classification accuracy when integrated with machine learning algorithms,with long short-term memory models achieving>90%accuracy in recent trials.However,persistent challenges,such as signal quality variability,motion artifacts,and limited clinical validation,hinder widespread adoption.Further innovation in sensor optimization,multimodal data integration,and real-world clinical trials is essential to translate portable EEG into a reliable diagnostic tool.This minireview underscores the transformative potential of neurotechnology in psychiatry while advocating for rigorous standard ization to bridge the gap between research and clinical practice.展开更多
With the rapid advancement of portable energy devices and sensor technologies,enhancing their catalytic performance,sensing capabilities,and application reliability has become a critical challenge in the fields of mat...With the rapid advancement of portable energy devices and sensor technologies,enhancing their catalytic performance,sensing capabilities,and application reliability has become a critical challenge in the fields of materials and energy science.Single-atom catalysts(SACs),owing to their high atomic utilization,outstanding catalytic activity,and precisely engineered structures enabled by density functional theory and enhanced by artificial intelligence,have shown tremendous potential in advancing portable energy and sensing technologies.While existing reviews predominantly focus on the application of SACs in individual portable devices,systematic discussions on their overall development prospects and challenges within portable energy and sensor fields remain scarce.Therefore,this review comprehensively explores the application potential and recent advancements of SACs in portable zinc-air batteries,proton exchange membrane fuel cells,and sensor technologies.The article highlights the influence of key factors such as material design,structural optimization,and packaging integration on device performance,while also addressing the primary bottlenecks and challenges encountered in current practical applications.Furthermore,it suggests possible future development directions,aiming to offer theoretical insights and engineering guidance for the large-scale deployment of SACs in wearable electronic devices,portable energy systems,and smart sensing technologies.展开更多
BACKGROUND Conventional reusable endoscopes have high disinfection costs because of their large size.In this study,we compared the effectiveness,safety,and operation performance of the portable disposable large-channe...BACKGROUND Conventional reusable endoscopes have high disinfection costs because of their large size.In this study,we compared the effectiveness,safety,and operation performance of the portable disposable large-channel endoscope that we developed with those of a conventional gastroscope in endoscopic submucosal dissection(ESD).AIM To compare two gastroscopes in ESD for effectiveness and safety.METHODS Ten Bama pigs were subjected to gastroscopy and ESD after general anesthesia.The experiment was completed by four experienced endoscopists.First,two endoscopists randomly selected the portable disposable large-channel or conventional gastroscope to complete gastroscopy procedures.The other two endoscopists assessed the quality of endoscopic images.After endoscopy,all of the endoscopists randomly used the portable disposable large-channel endoscope or the conventional gastroscope for ESD.Endoscopic operation performance,submucosal dissection time,total procedure time,total submucosal injection volume,specimen size,success rate of en bloc resection,muscular injury rate,and complications were compared between the endoscopes.RESULTS No significant differences in gastroscopy duration or in the integrity,sharpness,saturation,and brightness of the gastroscopic images were observed between the gastroscopes.For ESD,no significant differences in endoscopic operation performance,incision time,submucosal dissection time,total procedure time,total submucosal injection volume,specimen size,or success rate of en bloc resection were observed between the gastroscopes.Neither gastroscope caused muscular injury or treatment-related complica-tions.CONCLUSION The portable disposable large-channel endoscope can be used safely and effectively for gastroscopy and treatment.展开更多
Lactate,as a metabolite,plays a significant role in a number of fields,including medical diagnostics,exercise physiology and food science.Traditional methods for lactate measurement often involve expensive and cumbers...Lactate,as a metabolite,plays a significant role in a number of fields,including medical diagnostics,exercise physiology and food science.Traditional methods for lactate measurement often involve expensive and cumbersome instrumentation.This study developed a portable and low-cost lactate measurement system,including independently detectable hardware circuits and user-friendly embedded software,computer,and smartphone applications.The experiment verified that the relative error of the detection current in the device circuit was less than 1%.The electrochemical performance was measured by comparing the[Fe(CN)_(6)]^(3−)/[Fe(CN)_(6)]^(4−)solution with the desktop electrochemical workstation CHI660E,and a nearly consistent chronoamperometry(CA)curve was obtained.Two modified lactate sensors were used for CA testing of lactate.Within the concentration range of 0.1 mmol·L^(−1)to 20 mmol·L^(−1),there was a good linear relationship between lactate concentration and steady-state current,with a correlation coefficient(R2)greater than 0.99 and good repeatability,demonstrating the reliability of the developed device.The lactate measurement system developed in this study not only provides excellent detection performance and reliability,but also achieves portability and low cost,providing a new solution for lactate measurement.展开更多
Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant...Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant on traditional laptops and computers, which, while portable, lack true ultra-portability. This paper explores the potential impact of developing a dedicated, ultra-portable, low-cost device for on-the-go penetration testing. Such a device could replicate the core functionalities of advanced penetration testing tools, including those found in Kali Linux, within a compact form factor that fits easily into a pocket. By offering the convenience and portability akin to a smartphone, this innovative device could redefine the way penetration testers operate, enabling them to carry essential tools wherever they go and ensuring they are always prepared to conduct security assessments efficiently. This approach aims to revolutionize penetration testing by merging high functionality with unparalleled portability.展开更多
The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching.This study investigates the design of a low-consumption multiple nuclides ide...The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching.This study investigates the design of a low-consumption multiple nuclides identification algorithm for portable gamma spectrometers.First,the gamma spectra of 12 target nuclides(including the background case)were measured to create training datasets.The characteristic energies,obtained through energy calibration and full-energy peak addresses,are utilized as input features for a neural network.A large number of single-and multiple-nuclide training datasets are generated using random combinations and small-range drifting.Subsequently,a multi-label classification neural network based on a binary cross-entropy loss function is applied to export the existence probability of certain nuclides.The designed algorithm effectively reduces the computation time and storage space required by the neural network and has been successfully implemented in a portable gamma spectrometer with a running time of t_(r)<2 s.Results show that,in both validation and actual tests,the identification accuracy of the designed algorithm reaches 94.8%,for gamma spectra with a dose rate of d≈0.5μSv∕h and a measurement time t_(m)=60 s.This improves the ability to perform rapid on-site nuclide identification at important sites.展开更多
This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is ...This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is a sophisticated code that substantially relies on High-Performance Computing (HPC) environments, necessitating particular machine and software configurations. To facilitate community-based uELM developments employing GPUs, we have created a portable, standalone software environment preconfigured with uELM input datasets, simulation cases, and source code. This environment, utilizing Docker, encompasses all essential code, libraries, and system software for uELM development on GPUs. It also features a functional unit test framework and an offline model testbed for comprehensive numerical experiments. From a technical perspective, the paper discusses GPU-ready container generations, uELM code management, and input data distribution across computational platforms. Lastly, the paper demonstrates the use of environment for functional unit testing, end-to-end simulation on CPUs and GPUs, and collaborative code development.展开更多
Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration.By 2022,the CH_(4)concentration was approximately 1.9 ppm,which...Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration.By 2022,the CH_(4)concentration was approximately 1.9 ppm,which was 264%of the pre-industrial level.The spatiotemporal distribution of CH_(4)was investigated by a portable CH_(4)detector on an unmanned aerial vehicle and electric bicycles in Shaoxing,a city situated in the Yangtze River Delta,China.The vertical distribution revealed CH_(4)concentration generally decreased slowly with height.However,the inversion condition and low atmospheric boundary layer height(ABLH)leaded to the enhancement of CH_(4)with height.The highest CH_(4)concentration(2.2±0.1 ppm,n=1428)was observed in winter and the lowest(2.0±0.2 ppm,n=1530)in spring.Regarding the daily variation,CH_(4)concentration peaked at 5:00 local time(LT)and reached its lowest level at 14:00 LT,which was attributed to the daily variation of ABLH,lowest in the early morning and highest in the noon.In urban areas,CH_(4)concentrations showed higher levels near restaurants,natural gas stations and sewerage well,with a maximum value of 13.1 ppm,which was caused by CH_(4)emission and natural gas leakage from these places.The annual CH_(4)emission in Shaoxing were estimated to be approximately 69 ton/(km^(2)·year)by the mass balance approach.Compared with other cities in the world,the CH_(4)emission is in higher level which imply some control measures should be conducted to reduce CH_(4)emission in Shaoxing.展开更多
Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for ev...Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for evaluating the O_(3)production rate.Furthermore,O_(x)has proved to be a more representative indicator and can serve as a reflection of pollution prevention efficacy.A portable instrument for measuring atmospheric O_(x)and NO_(2)based on cavity ring-down spectroscopy(O_(x)/NO_(2)-CRDS)was developed in this work.The NO_(2)concentration is accurately mea-sured according to its absorption characteristic at 407.86 nm.Ambient O_(3)is converted into NO_(2)by chemical titration of high concentrations of nitrogen oxide(NO),and the O_(3)conversion efficiencies obtained are nearly 99%.The detection limit of the O_(x)/NO_(2)-CRDS system for O_(x)is 0.024 ppbv(0.1 s),and the overall uncertainty of the instrument is±6%.Moreover,the Kalman filtering technique was applied to improve the measurement accuracy of O_(x)/NO_(2)-CRDS.The system was applied in a comprehensive field observation campaign at Hefei Sci-ence Island from 26 to 30 September 2022,and the time concentration series and change characteristics of O_(x)and NO_(2)were obtained for five days.The measured O_(x)concentrations were compared with those of two com-mercial instruments,and the consistency was good(R^(2)=0.98),indicating that this system can be deployed to accurately and rapidly obtain the concentrations of atmospheric O_(x)and NO_(2).It will be a useful tool for assessing the atmospheric oxidation capacity and controlling O_(3)pollution.展开更多
Clinicians involved in HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome) prevention of mother to child transmission (PMTCT) programme and research activities can benefit from the advantag...Clinicians involved in HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome) prevention of mother to child transmission (PMTCT) programme and research activities can benefit from the advantages that computerized systems add to medical practice even in resource constrained sub-Saharan clinic settings. Their continued use of paper based systems presents clinical data management and patient care challenges. A portable point of care data capture electronic system and a computerized clinic patient management system (CCPMS) were implemented to remedy these challenges. PMTCT report compilation was easier with the portable data collection system whose data were found to be more complete and accurate with a 0.83% error rate compared to a 4.1% error rate in the paper registers. A resounding majority of clinicians preferred using the new CCPMS with many of the view that it improved drug inventory and general clinic management with a positive effect on patient care.展开更多
Black carbon(BC)is associated with adverse human health and climate change.Mapping BC spatial distribution imperatively requires low-cost and portable devices.Several portable BC monitors are commercially available,bu...Black carbon(BC)is associated with adverse human health and climate change.Mapping BC spatial distribution imperatively requires low-cost and portable devices.Several portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field observation.This study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their performance.The monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer AE33.The study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in algorithms.The results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),respectively.These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST.The study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic data.Based on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing applicable.The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.展开更多
Cracks,potholes,and other defects often occur on infrastructure such as bridges,among which cracks are one of the most frequent defects.They have diverse shapes and are difficult to detect.Traditional manual inspectio...Cracks,potholes,and other defects often occur on infrastructure such as bridges,among which cracks are one of the most frequent defects.They have diverse shapes and are difficult to detect.Traditional manual inspection methods are inefficient and have low accuracy,while automated inspection machines are bulky and inconvenient to carry and use.Based on the shortcomings of existing detection technologies,this paper proposes a portable structural surface crack detection system based on the Android platform using a portable hand-held image acquisition device.The system captures cracks on the structure's surface and obtains high-definition crack images.Then,these images are transmitted to portable smartphone terminals through Wi-Fi.Next,the image is pre-processed using weighted averaging,grayscale linear transformation,and adaptive median filtering.Then,the improved Canny edge detection algorithm is applied to identify crack information,and the edge segmentation algorithm is used to determine the crack width.Finally,based on camera calibration,the pixels are converted into the length data required for actual measurement.The results show that the system is easy to operate,and it not only has crack storage and tracking functions,but also can effectively measure the crack width on the surface of components.The measurement accuracy of this system reaches the sub-pixel level,and in actual testing,compared with the crack width gauge,the maximum relative error does notexceed6.25%.展开更多
Point-of-care testing(POCT)refers to a category of diagnostic tests that are performed at or near to the site of the patients(also called bedside testing)and is capable of obtaining accurate results in a short time by...Point-of-care testing(POCT)refers to a category of diagnostic tests that are performed at or near to the site of the patients(also called bedside testing)and is capable of obtaining accurate results in a short time by using portable diagnostic devices,avoiding sending samples to the medical laboratories.It has been extensively explored for diagnosing and monitoring patients’diseases and health conditions with the assistance of development in biochemistry and microfluidics.Microfluidic paper-based analytical devices(μPADs)have gained dramatic popularity in POCT because of their simplicity,user-friendly,fast and accurate result reading and low cost.SeveralμPADs have been successfully commercialized and received excellent feedback during the past several decades.This review briefly discusses the main types ofμPADs,preparation methods and their detection principles,followed by a few representative examples.The future perspectives of the development inμPADs are also provided.展开更多
The occurrence of geogenic arsenic(As)in groundwater is a global public health concern.However,there remain large gaps in groundwater As data,making it difficult to identify non-compliant domestic wells,partly due to ...The occurrence of geogenic arsenic(As)in groundwater is a global public health concern.However,there remain large gaps in groundwater As data,making it difficult to identify non-compliant domestic wells,partly due to lack of low-cost methods capable of rapid As analysis.Therefore,the development of high through-put and reliable on-site determination methods for inorganic As is essential.Herein,a portable automated analyzer was developed for the determination of arsenite(As(Ⅲ)),arsenate(As(Ⅴ))and phosphate in As contaminated groundwater based on a previously adapted method for molybdenum blue spectrophotometry.After the optimization of the chemical reactions and flow manifold,the system demonstrated a high sample through-put(4.8/h for As(Ⅲ),As(Ⅴ)and phosphate analysis),allowing this system to screen 125 samples in 24 h.Other advantages include low operational costs(0.3 CNY per sample),appropriate sensitivity for contaminated groundwater(detection limits of 4.7μg/L,8.3μg/L and 5.4μg/L for As(Ⅲ),As(Ⅴ)and phosphate,respectively),good linearity(R^(2)>0.9996 at As concentrations up to 1600μg/L)and high precision(relative standard deviations of 3.5% and 2.8% for As(Ⅲ)and As(Ⅴ),respectively).The portable system was successfully used for As speciation analysis in 5 groundwater samples collected from multi-level wells at Yinchuan Plain,northwestern China,with total As concentrations ranging from 75.7 to 295.0μg/L,independently assessing As speciation,providing a promising novel method for the rapid on-site screening of As in tens of millions of domestic wells worldwide.展开更多
To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,mo...To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,most people generate carbon emissions through their daily activities in space and time.They are also exposed to multiple environmental factors(e.g.,air pollution,noise,and greenspace).Changing people’s behaviors to reduce carbon emissions can also influence their multiple environmental exposures and further influence their health outcomes.Thus,this study seeks to examine the associations between individuals’daily carbon footprints and their exposures to multiple environmental factors(i.e.,air pollution,noise,and greenspace)across different spa-tial and temporal contexts using individual-level data collected by portable real-time sensors,an activity-travel diary,and a questionnaire from four communities in Hong Kong.The results first indicated that individuals’car-bon footprints of daily activities varied across different spatial and temporal contexts,with home and nighttime having the highest estimated carbon footprints.We also found that activity carbon footprints have a positive asso-ciation with PM2.5,which is particularly strong at home and from morning to nighttime,and mixed associations with noise(positive at home and nighttime,while negative in other places and during travel,from morning to afternoon).Besides,carbon footprints also have consistent negative associations with shrubland and woodland across different spatial and temporal contexts.The findings can provide essential insights into effective measures for promoting the transition to a low-carbon society.展开更多
The growing threat of malware,particularly in the Portable Executable(PE)format,demands more effective methods for detection and classification.Machine learning-based approaches exhibit their potential but often negle...The growing threat of malware,particularly in the Portable Executable(PE)format,demands more effective methods for detection and classification.Machine learning-based approaches exhibit their potential but often neglect semantic segmentation of malware files that can improve classification performance.This research applies deep learning to malware detection,using Convolutional Neural Network(CNN)architectures adapted to work with semantically extracted data to classify malware into malware families.Starting from the Malconv model,this study introduces modifications to adapt it to multi-classification tasks and improve its performance.It proposes a new innovative method that focuses on byte extraction from Portable Executable(PE)malware files based on their semantic location,resulting in higher accuracy in malware classification than traditional methods using full-byte sequences.This novel approach evaluates the importance of each semantic segment to improve classification accuracy.The results revealed that the header segment of PE files provides the most valuable information for malware identification,outperforming the other sections,and achieving an average classification accuracy of 99.54%.The above reaffirms the effectiveness of the semantic segmentation approach and highlights the critical role header data plays in improving malware detection and classification accuracy.展开更多
From energy generation to transportation,from energy distribution to storage,from semiconductor processing to communications,and from portable devices to data centers,energy consumption has grown to be a major limitat...From energy generation to transportation,from energy distribution to storage,from semiconductor processing to communications,and from portable devices to data centers,energy consumption has grown to be a major limitation to usability and performance.Therefore,energy-efficient technologies become an active research area motivated by energy necessity and environmental concerns.With energy-efficient technologies,a number of epoch-making technical approaches can be expected.Energy efficiency technologies are affecting all forms of energy conversion and all aspects of life.展开更多
Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is ...Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is verified in water quality testing.An M-type Czerny-Turner light path structure,a broadband light emitting diode(LED)light source,and a linear charge-coupled device(CCD)photodetector were adopted in ATOM.The performance of ATOM was validated through iron content determination by using o-phenanthroline spectrophotometry.The experiment results showed that the linear correlation coefficient of determination R^(2) was 0.9997 for mass concentrations ranging from 0 to 2.0μg/mL.The relative standard deviation was 0.37%,and the relative error compared to a commercial large-scale spectrophotometer was below 1.4%.The dimensions of ATOM are 75 mm×60 mm×25 mm,with hardware costs of approximately 1000 CNY.ATOM features compact size,low cost,rapid measurement,high integration and high precision,making it suitable for portable on-site rapid detection.展开更多
Non-road equipment is one of the key contributing sources to air pollution.Thus,an accurate development of emission inventory from non-road equipment is imperative for air quality management,especially for equipment w...Non-road equipment is one of the key contributing sources to air pollution.Thus,an accurate development of emission inventory from non-road equipment is imperative for air quality management,especially for equipment with a large population such as diesel-fueled forklifts.The objective of this paper is to characterize duty-cycle based emissions from diesel-fueled forklifts using a portable emission measurement system(PEMS).Three dutycycles were defined in this study,including idling,moving,and working(active duty operation)and used to characterize in-use emissions for diesel-fueled forklifts.A total of twelve diesel-fueled forklifts were selected for real-world emission measurements.Results showed that fuel-based emission factors appear to have smaller variability compared to time-based ones.For example,the time-based emission factors for CO,HC,NO,and PM 2.5 for forklifts were estimated to be 16.6-43.9,5.3-15.1,26.2-49.9,5.5-11.1 g/hr with the fuel-based emission factors being 12.1-20.3,4.1-8.3,19.1-32.4,3.5-6.5 g/kg-fuel,respectively.NO emissions appear to be the biggest concern for emissions control.Furthermore,most of the emissions factors estimated from this study are significantly different from those in both National Guideline for Emission Inventory Development for Non-Road Equipment in China and welldeveloped emission factor models such as NONROAD by US EPA.This implies that localized,preferably fuel-based emission factors should be adjusted based on real-world emission measurements in order to develop a representative emission inventory for non-road equipment.展开更多
基金funded by National Natural Science Foundation of China(No.82272134)Innovative Research Group Project of the National Natural Science Foundation of China(No.82272134,Xiao-lei Chen).
文摘Background and Objective Electromagnetic navigation technology has demonstrated significant potential in enhancing the accuracy and safety of neurosurgical procedures.However,traditional electromagnetic navigation systems face challenges such as high equipment costs,complex operation,bulky size,and insufficient anti-interference performance.To address these limitations,our study developed and validated a novel portable electromagnetic neuronavigation system designed to improve the precision,accessibility,and clinical applicability of electromagnetic navigation technology in cranial surgery.Methods The software and hardware architecture of a portable neural magnetic navigation system was designed.The key technologies of the system were analysed,including electromagnetic positioning algorithms,miniaturized sensor design,optimization of electromagnetic positioning and navigation algorithms,anti-interference signal processing methods,and fast three-dimensional reconstruction algorithms.A prototype was developed,and its accuracy was tested.Finally,a preliminary clinical application evaluation was conducted.Results This study successfully developed a comprehensive portable electromagnetic neuronavigation system capable of achieving preoperative planning,intraoperative real-time positioning and navigation,and postoperative evaluation of navigation outcomes.Through rigorous collaborative testing of the system’s software and hardware,the accuracy of electromagnetic neuronavigation has been validated to meet clinical requirements.Conclusions This study developed a portable neuroelectromagnetic navigation system and validated its effectiveness and safety through rigorous model testing and preliminary clinical applications.The system is characterized by its compact size,high precision,excellent portability,and user-friendly operation,making it highly valuable for promoting navigation technology and advancing the precision and minimally invasive nature of neurosurgical procedures.
基金Supported by Ministry of Science and Technology of the People’s Republic of China-Major Projects,No.2022ZD0212400National Natural Science Foundation of China,No.82371453.
文摘Traditional diagnostic tools for depression,such as the Patient Health Questionnaire-9,are susceptible to subjective bias,increasing the risk of misdiagnosis and emphasizing the critical need for objective biomarkers.This minireview evaluates the emerging role of portable electroencephalography(EEG)as a cost-effective,accessible solution for early depression detection.By synthesizing findings from 45 studies(selected from 764 screened articles),we highlight EEG’s capacity to identify aberrant neural oscillations associated with core depressive symptoms,including anhedonia,excessive guilt,and persistent low mood.Advances in portable systems demonstrate promising classification accuracy when integrated with machine learning algorithms,with long short-term memory models achieving>90%accuracy in recent trials.However,persistent challenges,such as signal quality variability,motion artifacts,and limited clinical validation,hinder widespread adoption.Further innovation in sensor optimization,multimodal data integration,and real-world clinical trials is essential to translate portable EEG into a reliable diagnostic tool.This minireview underscores the transformative potential of neurotechnology in psychiatry while advocating for rigorous standard ization to bridge the gap between research and clinical practice.
文摘With the rapid advancement of portable energy devices and sensor technologies,enhancing their catalytic performance,sensing capabilities,and application reliability has become a critical challenge in the fields of materials and energy science.Single-atom catalysts(SACs),owing to their high atomic utilization,outstanding catalytic activity,and precisely engineered structures enabled by density functional theory and enhanced by artificial intelligence,have shown tremendous potential in advancing portable energy and sensing technologies.While existing reviews predominantly focus on the application of SACs in individual portable devices,systematic discussions on their overall development prospects and challenges within portable energy and sensor fields remain scarce.Therefore,this review comprehensively explores the application potential and recent advancements of SACs in portable zinc-air batteries,proton exchange membrane fuel cells,and sensor technologies.The article highlights the influence of key factors such as material design,structural optimization,and packaging integration on device performance,while also addressing the primary bottlenecks and challenges encountered in current practical applications.Furthermore,it suggests possible future development directions,aiming to offer theoretical insights and engineering guidance for the large-scale deployment of SACs in wearable electronic devices,portable energy systems,and smart sensing technologies.
文摘BACKGROUND Conventional reusable endoscopes have high disinfection costs because of their large size.In this study,we compared the effectiveness,safety,and operation performance of the portable disposable large-channel endoscope that we developed with those of a conventional gastroscope in endoscopic submucosal dissection(ESD).AIM To compare two gastroscopes in ESD for effectiveness and safety.METHODS Ten Bama pigs were subjected to gastroscopy and ESD after general anesthesia.The experiment was completed by four experienced endoscopists.First,two endoscopists randomly selected the portable disposable large-channel or conventional gastroscope to complete gastroscopy procedures.The other two endoscopists assessed the quality of endoscopic images.After endoscopy,all of the endoscopists randomly used the portable disposable large-channel endoscope or the conventional gastroscope for ESD.Endoscopic operation performance,submucosal dissection time,total procedure time,total submucosal injection volume,specimen size,success rate of en bloc resection,muscular injury rate,and complications were compared between the endoscopes.RESULTS No significant differences in gastroscopy duration or in the integrity,sharpness,saturation,and brightness of the gastroscopic images were observed between the gastroscopes.For ESD,no significant differences in endoscopic operation performance,incision time,submucosal dissection time,total procedure time,total submucosal injection volume,specimen size,or success rate of en bloc resection were observed between the gastroscopes.Neither gastroscope caused muscular injury or treatment-related complica-tions.CONCLUSION The portable disposable large-channel endoscope can be used safely and effectively for gastroscopy and treatment.
基金supported by National Natural Science Foundation of China(No.62006092)Natural Science Research Project of Anhui Educational Committee(No.2023AH030081)+1 种基金2023 New Era Education Provincial Quality Engineering Project(Graduate Education)(No.2023cxcysj103)2024 New Era Education Provincial Quality Engineering Project(Graduate Education)。
文摘Lactate,as a metabolite,plays a significant role in a number of fields,including medical diagnostics,exercise physiology and food science.Traditional methods for lactate measurement often involve expensive and cumbersome instrumentation.This study developed a portable and low-cost lactate measurement system,including independently detectable hardware circuits and user-friendly embedded software,computer,and smartphone applications.The experiment verified that the relative error of the detection current in the device circuit was less than 1%.The electrochemical performance was measured by comparing the[Fe(CN)_(6)]^(3−)/[Fe(CN)_(6)]^(4−)solution with the desktop electrochemical workstation CHI660E,and a nearly consistent chronoamperometry(CA)curve was obtained.Two modified lactate sensors were used for CA testing of lactate.Within the concentration range of 0.1 mmol·L^(−1)to 20 mmol·L^(−1),there was a good linear relationship between lactate concentration and steady-state current,with a correlation coefficient(R2)greater than 0.99 and good repeatability,demonstrating the reliability of the developed device.The lactate measurement system developed in this study not only provides excellent detection performance and reliability,but also achieves portability and low cost,providing a new solution for lactate measurement.
文摘Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant on traditional laptops and computers, which, while portable, lack true ultra-portability. This paper explores the potential impact of developing a dedicated, ultra-portable, low-cost device for on-the-go penetration testing. Such a device could replicate the core functionalities of advanced penetration testing tools, including those found in Kali Linux, within a compact form factor that fits easily into a pocket. By offering the convenience and portability akin to a smartphone, this innovative device could redefine the way penetration testers operate, enabling them to carry essential tools wherever they go and ensuring they are always prepared to conduct security assessments efficiently. This approach aims to revolutionize penetration testing by merging high functionality with unparalleled portability.
文摘The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching.This study investigates the design of a low-consumption multiple nuclides identification algorithm for portable gamma spectrometers.First,the gamma spectra of 12 target nuclides(including the background case)were measured to create training datasets.The characteristic energies,obtained through energy calibration and full-energy peak addresses,are utilized as input features for a neural network.A large number of single-and multiple-nuclide training datasets are generated using random combinations and small-range drifting.Subsequently,a multi-label classification neural network based on a binary cross-entropy loss function is applied to export the existence probability of certain nuclides.The designed algorithm effectively reduces the computation time and storage space required by the neural network and has been successfully implemented in a portable gamma spectrometer with a running time of t_(r)<2 s.Results show that,in both validation and actual tests,the identification accuracy of the designed algorithm reaches 94.8%,for gamma spectra with a dose rate of d≈0.5μSv∕h and a measurement time t_(m)=60 s.This improves the ability to perform rapid on-site nuclide identification at important sites.
文摘This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is a sophisticated code that substantially relies on High-Performance Computing (HPC) environments, necessitating particular machine and software configurations. To facilitate community-based uELM developments employing GPUs, we have created a portable, standalone software environment preconfigured with uELM input datasets, simulation cases, and source code. This environment, utilizing Docker, encompasses all essential code, libraries, and system software for uELM development on GPUs. It also features a functional unit test framework and an offline model testbed for comprehensive numerical experiments. From a technical perspective, the paper discusses GPU-ready container generations, uELM code management, and input data distribution across computational platforms. Lastly, the paper demonstrates the use of environment for functional unit testing, end-to-end simulation on CPUs and GPUs, and collaborative code development.
基金supported by the National Natural Science Foundation of China(No.42327806)the National Key R&D Program of China(No.2022YFC3703500)+4 种基金Zhejiang Province“Lingyan”Research and Development Project(No.2022C03073)Zhejiang Provincial Natural Science Foundation of China(No.LQ23B070009)China Postdoctoral Science Foundation(No.2023M743763)Zhejiang Provincial Postdoctoral Research Excellence Funding Project(No.ZJ2023144)Shaoxing Science and Technology Plan Project(No.2022B41006).
文摘Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration.By 2022,the CH_(4)concentration was approximately 1.9 ppm,which was 264%of the pre-industrial level.The spatiotemporal distribution of CH_(4)was investigated by a portable CH_(4)detector on an unmanned aerial vehicle and electric bicycles in Shaoxing,a city situated in the Yangtze River Delta,China.The vertical distribution revealed CH_(4)concentration generally decreased slowly with height.However,the inversion condition and low atmospheric boundary layer height(ABLH)leaded to the enhancement of CH_(4)with height.The highest CH_(4)concentration(2.2±0.1 ppm,n=1428)was observed in winter and the lowest(2.0±0.2 ppm,n=1530)in spring.Regarding the daily variation,CH_(4)concentration peaked at 5:00 local time(LT)and reached its lowest level at 14:00 LT,which was attributed to the daily variation of ABLH,lowest in the early morning and highest in the noon.In urban areas,CH_(4)concentrations showed higher levels near restaurants,natural gas stations and sewerage well,with a maximum value of 13.1 ppm,which was caused by CH_(4)emission and natural gas leakage from these places.The annual CH_(4)emission in Shaoxing were estimated to be approximately 69 ton/(km^(2)·year)by the mass balance approach.Compared with other cities in the world,the CH_(4)emission is in higher level which imply some control measures should be conducted to reduce CH_(4)emission in Shaoxing.
基金supported by the National Natural Science Foundation of China[grant number 62275250]the Natural Science Foundation of Anhui Province[grant number 2008085J20]+1 种基金the National Key R&D Program of China[grant number 2022YFC3700301]the Anhui Provincial Key R&D Program[grant number 2022l07020022]。
文摘Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for evaluating the O_(3)production rate.Furthermore,O_(x)has proved to be a more representative indicator and can serve as a reflection of pollution prevention efficacy.A portable instrument for measuring atmospheric O_(x)and NO_(2)based on cavity ring-down spectroscopy(O_(x)/NO_(2)-CRDS)was developed in this work.The NO_(2)concentration is accurately mea-sured according to its absorption characteristic at 407.86 nm.Ambient O_(3)is converted into NO_(2)by chemical titration of high concentrations of nitrogen oxide(NO),and the O_(3)conversion efficiencies obtained are nearly 99%.The detection limit of the O_(x)/NO_(2)-CRDS system for O_(x)is 0.024 ppbv(0.1 s),and the overall uncertainty of the instrument is±6%.Moreover,the Kalman filtering technique was applied to improve the measurement accuracy of O_(x)/NO_(2)-CRDS.The system was applied in a comprehensive field observation campaign at Hefei Sci-ence Island from 26 to 30 September 2022,and the time concentration series and change characteristics of O_(x)and NO_(2)were obtained for five days.The measured O_(x)concentrations were compared with those of two com-mercial instruments,and the consistency was good(R^(2)=0.98),indicating that this system can be deployed to accurately and rapidly obtain the concentrations of atmospheric O_(x)and NO_(2).It will be a useful tool for assessing the atmospheric oxidation capacity and controlling O_(3)pollution.
文摘Clinicians involved in HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome) prevention of mother to child transmission (PMTCT) programme and research activities can benefit from the advantages that computerized systems add to medical practice even in resource constrained sub-Saharan clinic settings. Their continued use of paper based systems presents clinical data management and patient care challenges. A portable point of care data capture electronic system and a computerized clinic patient management system (CCPMS) were implemented to remedy these challenges. PMTCT report compilation was easier with the portable data collection system whose data were found to be more complete and accurate with a 0.83% error rate compared to a 4.1% error rate in the paper registers. A resounding majority of clinicians preferred using the new CCPMS with many of the view that it improved drug inventory and general clinic management with a positive effect on patient care.
基金supported by the National Natural Science Foundation of China(No.42075182)。
文摘Black carbon(BC)is associated with adverse human health and climate change.Mapping BC spatial distribution imperatively requires low-cost and portable devices.Several portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field observation.This study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their performance.The monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer AE33.The study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in algorithms.The results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),respectively.These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST.The study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic data.Based on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing applicable.The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.
基金Supported by Shaanxi Provincial Key Research and Development Program(2024GX-YBXM-288)the National Natural Science Foundation of China(52172324)+1 种基金Beilin District Science and Technology Program(GX2350)the Special Fund Project for Basic Research Business Expenses of Central level Public Welfare Research Institutes(2023-9062)。
文摘Cracks,potholes,and other defects often occur on infrastructure such as bridges,among which cracks are one of the most frequent defects.They have diverse shapes and are difficult to detect.Traditional manual inspection methods are inefficient and have low accuracy,while automated inspection machines are bulky and inconvenient to carry and use.Based on the shortcomings of existing detection technologies,this paper proposes a portable structural surface crack detection system based on the Android platform using a portable hand-held image acquisition device.The system captures cracks on the structure's surface and obtains high-definition crack images.Then,these images are transmitted to portable smartphone terminals through Wi-Fi.Next,the image is pre-processed using weighted averaging,grayscale linear transformation,and adaptive median filtering.Then,the improved Canny edge detection algorithm is applied to identify crack information,and the edge segmentation algorithm is used to determine the crack width.Finally,based on camera calibration,the pixels are converted into the length data required for actual measurement.The results show that the system is easy to operate,and it not only has crack storage and tracking functions,but also can effectively measure the crack width on the surface of components.The measurement accuracy of this system reaches the sub-pixel level,and in actual testing,compared with the crack width gauge,the maximum relative error does notexceed6.25%.
文摘Point-of-care testing(POCT)refers to a category of diagnostic tests that are performed at or near to the site of the patients(also called bedside testing)and is capable of obtaining accurate results in a short time by using portable diagnostic devices,avoiding sending samples to the medical laboratories.It has been extensively explored for diagnosing and monitoring patients’diseases and health conditions with the assistance of development in biochemistry and microfluidics.Microfluidic paper-based analytical devices(μPADs)have gained dramatic popularity in POCT because of their simplicity,user-friendly,fast and accurate result reading and low cost.SeveralμPADs have been successfully commercialized and received excellent feedback during the past several decades.This review briefly discusses the main types ofμPADs,preparation methods and their detection principles,followed by a few representative examples.The future perspectives of the development inμPADs are also provided.
基金supported by the Natural Science Foundation of Fujian Province(No.2020J06008)for Distinguished Young Scholarsthe Fujian Provincial Central Guided Local Science and Technology Development Special Project(No.2022L3078).
文摘The occurrence of geogenic arsenic(As)in groundwater is a global public health concern.However,there remain large gaps in groundwater As data,making it difficult to identify non-compliant domestic wells,partly due to lack of low-cost methods capable of rapid As analysis.Therefore,the development of high through-put and reliable on-site determination methods for inorganic As is essential.Herein,a portable automated analyzer was developed for the determination of arsenite(As(Ⅲ)),arsenate(As(Ⅴ))and phosphate in As contaminated groundwater based on a previously adapted method for molybdenum blue spectrophotometry.After the optimization of the chemical reactions and flow manifold,the system demonstrated a high sample through-put(4.8/h for As(Ⅲ),As(Ⅴ)and phosphate analysis),allowing this system to screen 125 samples in 24 h.Other advantages include low operational costs(0.3 CNY per sample),appropriate sensitivity for contaminated groundwater(detection limits of 4.7μg/L,8.3μg/L and 5.4μg/L for As(Ⅲ),As(Ⅴ)and phosphate,respectively),good linearity(R^(2)>0.9996 at As concentrations up to 1600μg/L)and high precision(relative standard deviations of 3.5% and 2.8% for As(Ⅲ)and As(Ⅴ),respectively).The portable system was successfully used for As speciation analysis in 5 groundwater samples collected from multi-level wells at Yinchuan Plain,northwestern China,with total As concentrations ranging from 75.7 to 295.0μg/L,independently assessing As speciation,providing a promising novel method for the rapid on-site screening of As in tens of millions of domestic wells worldwide.
基金supported by grants from the Hong Kong Re-search Grants Council(General Research Fund Grants No.14605920,14611621,14606922,14603724Collaborative Research Fund Grant No.C4023-20GF+3 种基金Research Matching Grants RMG 8601219,8601242,3110151)RGC Postdoctoral Fellowship No.PDFS2425-4H01)a grant from the Research Committee on Research Sustainability of Major Re-search Grants Council Funding Schemes(Grant No.3133235)of the Chinese University of Hong Kong(CUHK)grant from the Vice-Chancellor’s One-offDiscretionary Fund(Smart and Sustainable Cities:City of Commons)(4930787)of CUHK.
文摘To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,most people generate carbon emissions through their daily activities in space and time.They are also exposed to multiple environmental factors(e.g.,air pollution,noise,and greenspace).Changing people’s behaviors to reduce carbon emissions can also influence their multiple environmental exposures and further influence their health outcomes.Thus,this study seeks to examine the associations between individuals’daily carbon footprints and their exposures to multiple environmental factors(i.e.,air pollution,noise,and greenspace)across different spa-tial and temporal contexts using individual-level data collected by portable real-time sensors,an activity-travel diary,and a questionnaire from four communities in Hong Kong.The results first indicated that individuals’car-bon footprints of daily activities varied across different spatial and temporal contexts,with home and nighttime having the highest estimated carbon footprints.We also found that activity carbon footprints have a positive asso-ciation with PM2.5,which is particularly strong at home and from morning to nighttime,and mixed associations with noise(positive at home and nighttime,while negative in other places and during travel,from morning to afternoon).Besides,carbon footprints also have consistent negative associations with shrubland and woodland across different spatial and temporal contexts.The findings can provide essential insights into effective measures for promoting the transition to a low-carbon society.
文摘The growing threat of malware,particularly in the Portable Executable(PE)format,demands more effective methods for detection and classification.Machine learning-based approaches exhibit their potential but often neglect semantic segmentation of malware files that can improve classification performance.This research applies deep learning to malware detection,using Convolutional Neural Network(CNN)architectures adapted to work with semantically extracted data to classify malware into malware families.Starting from the Malconv model,this study introduces modifications to adapt it to multi-classification tasks and improve its performance.It proposes a new innovative method that focuses on byte extraction from Portable Executable(PE)malware files based on their semantic location,resulting in higher accuracy in malware classification than traditional methods using full-byte sequences.This novel approach evaluates the importance of each semantic segment to improve classification accuracy.The results revealed that the header segment of PE files provides the most valuable information for malware identification,outperforming the other sections,and achieving an average classification accuracy of 99.54%.The above reaffirms the effectiveness of the semantic segmentation approach and highlights the critical role header data plays in improving malware detection and classification accuracy.
文摘From energy generation to transportation,from energy distribution to storage,from semiconductor processing to communications,and from portable devices to data centers,energy consumption has grown to be a major limitation to usability and performance.Therefore,energy-efficient technologies become an active research area motivated by energy necessity and environmental concerns.With energy-efficient technologies,a number of epoch-making technical approaches can be expected.Energy efficiency technologies are affecting all forms of energy conversion and all aspects of life.
基金National Natural Science Foundation of China(No.62375048)Natural Science Foundation of Shanghai,China(No.22ZR1402600。
文摘Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is verified in water quality testing.An M-type Czerny-Turner light path structure,a broadband light emitting diode(LED)light source,and a linear charge-coupled device(CCD)photodetector were adopted in ATOM.The performance of ATOM was validated through iron content determination by using o-phenanthroline spectrophotometry.The experiment results showed that the linear correlation coefficient of determination R^(2) was 0.9997 for mass concentrations ranging from 0 to 2.0μg/mL.The relative standard deviation was 0.37%,and the relative error compared to a commercial large-scale spectrophotometer was below 1.4%.The dimensions of ATOM are 75 mm×60 mm×25 mm,with hardware costs of approximately 1000 CNY.ATOM features compact size,low cost,rapid measurement,high integration and high precision,making it suitable for portable on-site rapid detection.
文摘Non-road equipment is one of the key contributing sources to air pollution.Thus,an accurate development of emission inventory from non-road equipment is imperative for air quality management,especially for equipment with a large population such as diesel-fueled forklifts.The objective of this paper is to characterize duty-cycle based emissions from diesel-fueled forklifts using a portable emission measurement system(PEMS).Three dutycycles were defined in this study,including idling,moving,and working(active duty operation)and used to characterize in-use emissions for diesel-fueled forklifts.A total of twelve diesel-fueled forklifts were selected for real-world emission measurements.Results showed that fuel-based emission factors appear to have smaller variability compared to time-based ones.For example,the time-based emission factors for CO,HC,NO,and PM 2.5 for forklifts were estimated to be 16.6-43.9,5.3-15.1,26.2-49.9,5.5-11.1 g/hr with the fuel-based emission factors being 12.1-20.3,4.1-8.3,19.1-32.4,3.5-6.5 g/kg-fuel,respectively.NO emissions appear to be the biggest concern for emissions control.Furthermore,most of the emissions factors estimated from this study are significantly different from those in both National Guideline for Emission Inventory Development for Non-Road Equipment in China and welldeveloped emission factor models such as NONROAD by US EPA.This implies that localized,preferably fuel-based emission factors should be adjusted based on real-world emission measurements in order to develop a representative emission inventory for non-road equipment.