Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflo...Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research.展开更多
Background:Due to the widespread use of cell phone devices today,numerous re-search studies have focused on the adverse effects of electromagnetic radiation on human neuropsychological and reproductive systems.In most...Background:Due to the widespread use of cell phone devices today,numerous re-search studies have focused on the adverse effects of electromagnetic radiation on human neuropsychological and reproductive systems.In most studies,oxidative stress has been identified as the primary pathophysiological mechanism underlying the harmful effects of electromagnetic waves.This paper aims to provide a holistic review of the protective effects of melatonin against cell phone-induced electromag-netic waves on various organs.Methods:This study is a systematic review of articles chosen by searching Google Scholar,PubMed,Embase,Scopus,Web of Science,and Science Direct using the key-words‘melatonin’,‘cell phone radiation’,and‘animal model’.The search focused on articles written in English,which were reviewed and evaluated.The PRISMA process was used to review the articles chosen for the study,and the JBI checklist was used to check the quality of the reviewed articles.Results:In the final review of 11 valid quality-checked articles,the effects of me-latonin in the intervention group,the effects of electromagnetic waves in the case group,and the amount of melatonin in the chosen organ,i.e.brain,skin,eyes,testis and the kidney were thoroughly examined.The review showed that electromagnetic waves increase cellular anti-oxidative activity in different tissues such as the brain,the skin,the eyes,the testis,and the kidneys.Melatonin can considerably augment the anti-oxidative system of cells and protect tissues;these measurements were sig-nificantly increased in control groups.Electromagnetic waves can induce tissue atro-phy and cell death in various organs including the brain and the skin and this effect was highly decreased by melatonin.Conclusion:Our review confirms that melatonin effectively protects the organs of an-imal models against electromagnetic waves.In light of this conclusion and the current world-wide use of melatonin,future studies should advance to the stages of human clinical trials.We also recommend that more research in the field of melatonin physi-ology is conducted in order to protect exposed cells from dying and that melatonin should be considered as a pharmaceutical option for treating the complications result-ing from electromagnetic waves in humans.展开更多
Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has...Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.展开更多
This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on in...This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on indoor thermal comfort,temperature distribution,humidity,and energy consumption.Results show that increasing WWR amplifies indoor temperature fluctuations.While the overall predicted mean vote(PMV)remains within the Level-II comfort range(−1.0 to+1.0),the FC system exhibits pronounced local PMV gradients near west-facing windows,especially at 80%WWR,where transient PMV reaches 1.26 close to the window,0.89 higher than at the room center.In contrast,the FR+FC system significantly reduces spatial PMV variations,maintaining local PMV within acceptable limits for most of the day.Energy analysis reveals that FC energy consumption rises with WWR,increasing by 7.11%from 40%to 80%WWR,whereas FR+FC energy use decreases by 29.26%over the same range,demonstrating its superior handling of radiant loads.Furthermore,the convective-radiant system exhibits a high average hourly cooling performance coefficient.These findings indicate that FR+FC systems provide better thermal comfort and energy efficiency in high-WWR spaces,making them particularly suitable for summer operation in window-intensive buildings.展开更多
In recent years,the world has seen an exponential increase in energy demand,prompting scientists to look for innovative ways to exploit the power sun’s power.Solar energy technologies use the sun’s energy and light ...In recent years,the world has seen an exponential increase in energy demand,prompting scientists to look for innovative ways to exploit the power sun’s power.Solar energy technologies use the sun’s energy and light to provide heating,lighting,hot water,electricity and even cooling for homes,businesses,and industries.Therefore,ground-level solar radiation data is important for these applications.Thus,our work aims to use a mathematical modeling tool to predict solar irradiation.For this purpose,we are interested in the application of the Adaptive Neuro Fuzzy Inference System.Through this type of artificial neural system,10 models were developed,based on meteorological data such as the Day number(Nj),Ambient temperature(T),Relative Humidity(Hr),Wind speed(WS),Wind direction(WD),Declination(δ),Irradiation outside the atmosphere(Goh),Maximum temperature(Tmax),Minimum temperature(Tmin).These models have been tested by different static indicators to choose the most suitable one for the estimation of the daily global solar radiation.This study led us to choose the M8 model,which takes Nj,T,Hr,δ,Ws,Wd,G0,and S0 as input variables because it presents the best performance either in the learning phase(R^(2)=0.981,RMSE=0.107 kW/m^(2),MAE=0.089 kW/m2)or in the validation phase(R^(2)=0.979,RMSE=0.117 kW/m^(2),MAE=0.101 kW/m^(2)).展开更多
The resource-intensive,high-fidelity infrared signature simulations and Radar CrossSection(RCS)calculations limit the integrated optimization of Unmanned Combat Aerial Vehicles(UCAVs)in response to escalating threats ...The resource-intensive,high-fidelity infrared signature simulations and Radar CrossSection(RCS)calculations limit the integrated optimization of Unmanned Combat Aerial Vehicles(UCAVs)in response to escalating threats from joint detection systems.To this end,we present a sample-efficient framework to advance the optimization efficiency of UCAV's exhaust system,focusing on both the stealth characteristics evaluation and the optimization process.A novel multi-fidelity stealth assessment method,powered by multi-fidelity neural network and local perceptive fields,has been developed to fuse different fidelity information from infrared radiation signature and RCS values,respectively.Results demonstrate that the method can achieve relatively high accuracy based on a small set of high-fidelity data.Furthermore,this data fusion method is integrated into a multi-objective Bayesian optimization framework.Employing a Gaussian process regression model and the EHVI acquisition function,the framework effectively explores the stealth objective space,achieving a 15.21%hypervolume indicator increase with fewer optimization iterations compared to NSGA-Ⅱ.Results show that the optimized nozzle significantly reduces both the infrared signature and RCS compared to the baseline configuration.The proposed framework offers a practical and efficient approach for optimizing the integrated stealth performance of UCAVs.展开更多
BACKGROUND The use of intravascular ultrasound(iUS)has been shown in multiple singlecenter retrospective studies to decrease procedure time,radiation exposure,and needle passes compared to conventional fluoroscopic gu...BACKGROUND The use of intravascular ultrasound(iUS)has been shown in multiple singlecenter retrospective studies to decrease procedure time,radiation exposure,and needle passes compared to conventional fluoroscopic guidance in the creation of a transjugular intrahepatic portosystemic shunt(TIPS).However,there are few data regarding the impact of imaging guidance modality choice on clinical outcomes.AIM To determine the impact of iUS vs fluoroscopic guidance during creation of a TIPS on procedural metrics,liver injury,shunt patency and mortality.METHODS The retrospective study cohort consisted of 66 patients who underwent TIPS creation using iUS[“iUS-guided TIPS(iTIPS)group”]and 135 patients who underwent TIPS creation using fluoroscopic guidance[“conventional fluoroscopic-guided TIPS(cTIPS)group”]at 2 tertiary academic medical centers from 2015-2019.TIPS that required variceal embolization or portal vein recanalization were excluded.RESULTS The technical success rate was 100%in the iTIPS group and 96%in the cTIPS group(P=0.17).The iTIPS group had an air kerma(266±254 mGy vs 1235±1049 mGy,P<0.00001),dose area product(5728±6518 uGy×m^(2) vs 28969±19067 uGy×m^(2),P<0.00001),fluoroscopy time(18.7±9.6 minutes vs 32.3±19.0 minutes,P<0.00001),and total procedure time(93±40 minutes vs 110±51 minutes,P=0.01)which were significantly lower than the cTIPS group.There was no significant difference in liver function test adverse event grade at 1 month.With a median follow-up of 26 months(inter quartile range:6-61 months),there was no difference between the two groups in terms of thrombosis-free survival(P=0.23),intervention-free survival(P=0.29),or patient mortality(P=0.61).CONCLUSION The use of iUS in the creation of TIPS reduces radiation exposure and procedure time compared with fluoroscopic guidance.At midterm follow-up,the imaging guidance modality did not affect shunt patency or mortality.展开更多
Radiator cooling configurations need to account for both efficient heat dissipation and energy conservation requirements.Rapid and rational determination of cooling system configurations constitutes a critical aspect ...Radiator cooling configurations need to account for both efficient heat dissipation and energy conservation requirements.Rapid and rational determination of cooling system configurations constitutes a critical aspect of transformer design,enhancing electrical power energy utilization efficiency.Computational fluid dynamics(CFD)is widely recognized as a well-established technique for simulating and optimizing heat dissipation systems.However,this approach is time-consuming because of pre-processing procedures,such as meshing.This paper proposes a fast iterative optimization model for calculating the outlet oil temperature and airflow distribution.Based on the analytical model results,this paper identifies the optimal energy-saving range for radiator cooling configurations,incorporating the cooperative effects of cooling efficiency,air pressure drop during heat transfer,and inlet–outlet temperature difference.The analytical model demonstrated errors in energy dissipation and temperature difference calculations within an acceptable range.The calculation time was reduced by more than 99%.Radiator configurations within the optimal range effectively minimize energy waste while meeting the target temperature difference and enhancing cooling efficiency.Finally,the PC2600-22/520 radiator was utilized to validate the accuracy of the analytical model and the rationality of the co-optimal intervals.展开更多
The present review explores the promising role of nanofluids and related hybrid variants in enhancing the efficiencyof flat tube car radiators.As vehicles become more advanced and demand better thermal performance,tra...The present review explores the promising role of nanofluids and related hybrid variants in enhancing the efficiencyof flat tube car radiators.As vehicles become more advanced and demand better thermal performance,traditional coolants are starting to fall short.Nanofluids,which involve tiny nanoparticles dispersed into standardcooling liquids,offer a new solution by significantly improving heat transfer capabilities.The article categorizesthe different types of nanofluids(ranging from those based on metals and metal oxides to carbon materials andhybrid combinations)and examines their effects on the improvement of radiator performance.General consensusexists in the literature that nanofluids can support better heat dissipation and enable accordingly the developmentof smaller and lighter radiators,which require less coolant and allow more compact vehicle designs.However,thisreview demonstrates that the use of nanofluids does not come without challenges.These include the long-termstability of these fluids and material compatibility issues.A critical discussion is therefore elaborated about thegaps to be filled and the steps to be undertaken to promote and standardize the use of these fluids in the industry.展开更多
BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with ...BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.展开更多
基金supported by the Tianjin Science and Technology Project(Project No.19JCTPJC44300)The Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Project No.2018KJ261)Science and Technology Program Project of Jin Nan District Tianjin(Project Nos.201805015&20190111).
文摘Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research.
基金Deputy for Research and Technology,Kermanshah University of Medical Sciences,Grant/Award Number:4030031。
文摘Background:Due to the widespread use of cell phone devices today,numerous re-search studies have focused on the adverse effects of electromagnetic radiation on human neuropsychological and reproductive systems.In most studies,oxidative stress has been identified as the primary pathophysiological mechanism underlying the harmful effects of electromagnetic waves.This paper aims to provide a holistic review of the protective effects of melatonin against cell phone-induced electromag-netic waves on various organs.Methods:This study is a systematic review of articles chosen by searching Google Scholar,PubMed,Embase,Scopus,Web of Science,and Science Direct using the key-words‘melatonin’,‘cell phone radiation’,and‘animal model’.The search focused on articles written in English,which were reviewed and evaluated.The PRISMA process was used to review the articles chosen for the study,and the JBI checklist was used to check the quality of the reviewed articles.Results:In the final review of 11 valid quality-checked articles,the effects of me-latonin in the intervention group,the effects of electromagnetic waves in the case group,and the amount of melatonin in the chosen organ,i.e.brain,skin,eyes,testis and the kidney were thoroughly examined.The review showed that electromagnetic waves increase cellular anti-oxidative activity in different tissues such as the brain,the skin,the eyes,the testis,and the kidneys.Melatonin can considerably augment the anti-oxidative system of cells and protect tissues;these measurements were sig-nificantly increased in control groups.Electromagnetic waves can induce tissue atro-phy and cell death in various organs including the brain and the skin and this effect was highly decreased by melatonin.Conclusion:Our review confirms that melatonin effectively protects the organs of an-imal models against electromagnetic waves.In light of this conclusion and the current world-wide use of melatonin,future studies should advance to the stages of human clinical trials.We also recommend that more research in the field of melatonin physi-ology is conducted in order to protect exposed cells from dying and that melatonin should be considered as a pharmaceutical option for treating the complications result-ing from electromagnetic waves in humans.
基金supported by the National Research Council of Thailand(No.NRCT-5-RSA63004-16)Chiang Mai University.S.Pakluea acknowledges scholarship support from the Science Achievement Scholarship of Thailand(SAST).
文摘Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.
基金supported by the Open Fund(Nos.202303 and 202304)of the Sichuan Province Engineering Technology Research Center of Healthy Human SettlementKey Research and Development Program of Sichuan Province(2022YFG0138)supported by Postgraduate Innovation Fund Project by Southwest University of Science and Technology(25ycx1084).
文摘This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on indoor thermal comfort,temperature distribution,humidity,and energy consumption.Results show that increasing WWR amplifies indoor temperature fluctuations.While the overall predicted mean vote(PMV)remains within the Level-II comfort range(−1.0 to+1.0),the FC system exhibits pronounced local PMV gradients near west-facing windows,especially at 80%WWR,where transient PMV reaches 1.26 close to the window,0.89 higher than at the room center.In contrast,the FR+FC system significantly reduces spatial PMV variations,maintaining local PMV within acceptable limits for most of the day.Energy analysis reveals that FC energy consumption rises with WWR,increasing by 7.11%from 40%to 80%WWR,whereas FR+FC energy use decreases by 29.26%over the same range,demonstrating its superior handling of radiant loads.Furthermore,the convective-radiant system exhibits a high average hourly cooling performance coefficient.These findings indicate that FR+FC systems provide better thermal comfort and energy efficiency in high-WWR spaces,making them particularly suitable for summer operation in window-intensive buildings.
文摘In recent years,the world has seen an exponential increase in energy demand,prompting scientists to look for innovative ways to exploit the power sun’s power.Solar energy technologies use the sun’s energy and light to provide heating,lighting,hot water,electricity and even cooling for homes,businesses,and industries.Therefore,ground-level solar radiation data is important for these applications.Thus,our work aims to use a mathematical modeling tool to predict solar irradiation.For this purpose,we are interested in the application of the Adaptive Neuro Fuzzy Inference System.Through this type of artificial neural system,10 models were developed,based on meteorological data such as the Day number(Nj),Ambient temperature(T),Relative Humidity(Hr),Wind speed(WS),Wind direction(WD),Declination(δ),Irradiation outside the atmosphere(Goh),Maximum temperature(Tmax),Minimum temperature(Tmin).These models have been tested by different static indicators to choose the most suitable one for the estimation of the daily global solar radiation.This study led us to choose the M8 model,which takes Nj,T,Hr,δ,Ws,Wd,G0,and S0 as input variables because it presents the best performance either in the learning phase(R^(2)=0.981,RMSE=0.107 kW/m^(2),MAE=0.089 kW/m2)or in the validation phase(R^(2)=0.979,RMSE=0.117 kW/m^(2),MAE=0.101 kW/m^(2)).
基金supported by the National Natural Science Foundation of China(No.12102356)。
文摘The resource-intensive,high-fidelity infrared signature simulations and Radar CrossSection(RCS)calculations limit the integrated optimization of Unmanned Combat Aerial Vehicles(UCAVs)in response to escalating threats from joint detection systems.To this end,we present a sample-efficient framework to advance the optimization efficiency of UCAV's exhaust system,focusing on both the stealth characteristics evaluation and the optimization process.A novel multi-fidelity stealth assessment method,powered by multi-fidelity neural network and local perceptive fields,has been developed to fuse different fidelity information from infrared radiation signature and RCS values,respectively.Results demonstrate that the method can achieve relatively high accuracy based on a small set of high-fidelity data.Furthermore,this data fusion method is integrated into a multi-objective Bayesian optimization framework.Employing a Gaussian process regression model and the EHVI acquisition function,the framework effectively explores the stealth objective space,achieving a 15.21%hypervolume indicator increase with fewer optimization iterations compared to NSGA-Ⅱ.Results show that the optimized nozzle significantly reduces both the infrared signature and RCS compared to the baseline configuration.The proposed framework offers a practical and efficient approach for optimizing the integrated stealth performance of UCAVs.
文摘BACKGROUND The use of intravascular ultrasound(iUS)has been shown in multiple singlecenter retrospective studies to decrease procedure time,radiation exposure,and needle passes compared to conventional fluoroscopic guidance in the creation of a transjugular intrahepatic portosystemic shunt(TIPS).However,there are few data regarding the impact of imaging guidance modality choice on clinical outcomes.AIM To determine the impact of iUS vs fluoroscopic guidance during creation of a TIPS on procedural metrics,liver injury,shunt patency and mortality.METHODS The retrospective study cohort consisted of 66 patients who underwent TIPS creation using iUS[“iUS-guided TIPS(iTIPS)group”]and 135 patients who underwent TIPS creation using fluoroscopic guidance[“conventional fluoroscopic-guided TIPS(cTIPS)group”]at 2 tertiary academic medical centers from 2015-2019.TIPS that required variceal embolization or portal vein recanalization were excluded.RESULTS The technical success rate was 100%in the iTIPS group and 96%in the cTIPS group(P=0.17).The iTIPS group had an air kerma(266±254 mGy vs 1235±1049 mGy,P<0.00001),dose area product(5728±6518 uGy×m^(2) vs 28969±19067 uGy×m^(2),P<0.00001),fluoroscopy time(18.7±9.6 minutes vs 32.3±19.0 minutes,P<0.00001),and total procedure time(93±40 minutes vs 110±51 minutes,P=0.01)which were significantly lower than the cTIPS group.There was no significant difference in liver function test adverse event grade at 1 month.With a median follow-up of 26 months(inter quartile range:6-61 months),there was no difference between the two groups in terms of thrombosis-free survival(P=0.23),intervention-free survival(P=0.29),or patient mortality(P=0.61).CONCLUSION The use of iUS in the creation of TIPS reduces radiation exposure and procedure time compared with fluoroscopic guidance.At midterm follow-up,the imaging guidance modality did not affect shunt patency or mortality.
基金supported in part by the National Natural Science Foundation of China under Grant 52207180Guangdong Basic and Applied Basic Research Foundation under Grant 2021A1515110435Anhui Provincial Natural Science Foundation under Grant 2208085UD18.
文摘Radiator cooling configurations need to account for both efficient heat dissipation and energy conservation requirements.Rapid and rational determination of cooling system configurations constitutes a critical aspect of transformer design,enhancing electrical power energy utilization efficiency.Computational fluid dynamics(CFD)is widely recognized as a well-established technique for simulating and optimizing heat dissipation systems.However,this approach is time-consuming because of pre-processing procedures,such as meshing.This paper proposes a fast iterative optimization model for calculating the outlet oil temperature and airflow distribution.Based on the analytical model results,this paper identifies the optimal energy-saving range for radiator cooling configurations,incorporating the cooperative effects of cooling efficiency,air pressure drop during heat transfer,and inlet–outlet temperature difference.The analytical model demonstrated errors in energy dissipation and temperature difference calculations within an acceptable range.The calculation time was reduced by more than 99%.Radiator configurations within the optimal range effectively minimize energy waste while meeting the target temperature difference and enhancing cooling efficiency.Finally,the PC2600-22/520 radiator was utilized to validate the accuracy of the analytical model and the rationality of the co-optimal intervals.
文摘The present review explores the promising role of nanofluids and related hybrid variants in enhancing the efficiencyof flat tube car radiators.As vehicles become more advanced and demand better thermal performance,traditional coolants are starting to fall short.Nanofluids,which involve tiny nanoparticles dispersed into standardcooling liquids,offer a new solution by significantly improving heat transfer capabilities.The article categorizesthe different types of nanofluids(ranging from those based on metals and metal oxides to carbon materials andhybrid combinations)and examines their effects on the improvement of radiator performance.General consensusexists in the literature that nanofluids can support better heat dissipation and enable accordingly the developmentof smaller and lighter radiators,which require less coolant and allow more compact vehicle designs.However,thisreview demonstrates that the use of nanofluids does not come without challenges.These include the long-termstability of these fluids and material compatibility issues.A critical discussion is therefore elaborated about thegaps to be filled and the steps to be undertaken to promote and standardize the use of these fluids in the industry.
文摘BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.
