BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different tre...BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good.展开更多
In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-b...In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-based alloy(typically pure lead or lead-bismuth eutectic(LBE))is used as the coolant.To clarify the pressure build-up characteristics under water-jet injection,this study conducted several experiments by injecting pressurized water into a molten LBE pool at Sun Yat-sen University.To obtain a further understanding,several new experimental parameters were adopted,including the melt temperature,water subcooling,injection pressure,injection duration,and nozzle diameter.Through detailed analyses,it was found that the pressure and temperature during the water-melt interaction exhibited a consistent variation trend with our previous water-droplet injection mode LBE experiment.Similarly,the existence of a steam explosion was confirmed,which typically results in a much stronger pressure build-up.For the non-explosion cases,increasing the injection pressure,melt-pool temperature,nozzle diameter,and water subcooling promoted pressure build-up in the melt pool.However,a limited enhancement effect was observed when increasing the injection duration,which may be owing to the continually rising pressure in the interaction vessel or the isolation effect of the generated steam cavity.Regardless of whether a steam explosion occurred,the calculated mechanical and kinetic energy conversion efficiencies of the melt were relatively small(not exceeding 4.1%and 0.7%,respectively).Moreover,the range of the conversion efficiency was similar to that of previous water-droplet experiments,although the upper limit of the jet mode was slightly lower.展开更多
BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resol...BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resolve,several treatment options have been suggested for this condition.CASE SUMMARY In this paper,we report a case of corticosteroid injection induced lipoatrophy treated with autologous whole blood(AWB)injection,as the condition had been unresponsive to fractional laser therapy.A 29-year-old female patient visited the dermatology clinic complaining of skin depression on her right buttock area,which had appeared six months earlier.There had been only subtle improvement at the margins after fractional CO_(2) laser treatment;therefore,after obtaining informed consent from the patient,AWB treatment was initiated.One month after the first AWB injection,the size and depth of the lesion had noticeably improved,and a slight improvement was also observed in discoloration.CONCLUSION Close observation is the initial treatment of choice for steroid induced skin atrophy;however,for patients in need of immediate cosmetic improvement,AWB injection may be a safe and cost-effective alternative.展开更多
The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics ...The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics of frozen sodium sulfate saline sandy soil,a series of uniaxial compression tests were performed by integrating digital image correlation(DIC)technology into the testing apparatus.The evolution law of the uniaxial compression strength(UCS),the failure strain,and the formation of the shear band of the frozen sodium sulfate saline sandy soil were analyzed.The test results show that within the scope of this study,with the increase of salt content,both the UCS and the shear band angle initially decrease with increasing salt content before showing an increase.In contrast,the failure strain and the width of the shear band exhibit an initial increase followed by a decrease in the samples.In addition,to investigate the brittle failure characteristics of frozen sodium sulfate saline sandy soil,two classic brittleness evaluation methods were employed to quantitatively assess the brittleness level for the soil samples.The findings suggest that the failure characteristics under all test conditions in this study belong to the transition stage between brittle and ductile,indicating that frozen sodium sulfate saline sandy soil exhibits certain brittle behavior under uniaxial compression conditions,and the brittleness index basically decreases and then increases with the rise in salt content.展开更多
The effect of deformation resistance of AlCr_(1.3)TiNi_(2) eutectic high-entropy alloys under various current densities and strain rates was investigated during electrically-assisted compression.Results show that at c...The effect of deformation resistance of AlCr_(1.3)TiNi_(2) eutectic high-entropy alloys under various current densities and strain rates was investigated during electrically-assisted compression.Results show that at current density of 60 A/mm^(2) and strain rate of 0.1 s^(−1),the ultimate tensile stress shows a significant decrease from approximately 3000 MPa to 1900 MPa with reduction ratio of about 36.7%.However,as current density increases,elongation decreases due to intermediate temperature embrittlement.This is because the current induces Joule effect,which then leads to stress concentration and more defect formation.Moreover,the flow stress is decreased with the increase in strain rate at constant current density.展开更多
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio...The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.展开更多
Chronic migraine is a potentially debilitating condition that can be detrimental to someone’s quality of life. Clinical data has proven OnabotulinumtoxinA (BoNT-A) to be an effective prophylactic treatment for chroni...Chronic migraine is a potentially debilitating condition that can be detrimental to someone’s quality of life. Clinical data has proven OnabotulinumtoxinA (BoNT-A) to be an effective prophylactic treatment for chronic headache types, and it is now regularly employed by headache treatment centers. The PREEMPT injection protocol has become the standard treatment regimen surrounding Botox injections for chronic migraine treatment since it was granted approval by the FDA in 2010. This retrospective chart review of patients treated for chronic migraine at Maine Comprehensive Pain Management in Scarborough, Maine, presents an alteration to the standard PREEMPT injection paradigm that reinforces the efficacy of Botox for chronic migraine treatment. We will discuss our Modified PREEMPT injection paradigm, which yields a positive clinical response rate of 95% of patients achieving at least 50% improvement in their migraine headaches. This appears to be the highest established response rate in the literature to date.展开更多
Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG h...Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG high pressure direct injection(HPDI)engine are examined.Four typical split injection strategies,namely split pre-injection of pilot diesel(PD)and NG,split post-injection of PD and NG,split pre-injection of NG,and split post-injection of PD,were developed to investigate the influences on combustion and emissions.Results revealed that split pre injection of NG enhanced the atomization of PD,whereas the split post-injection of NG lowered the temperature in the core region of the PD spray,resulting in the deterioration of combustion.The effect of the split injection strategy on indicated thermal efficiency exceeded 7.5%.Split pre-injection was favorable to enhancing thermal efficiency,whereas split post-injection was not.Ignition delay,combustion duration,and premixed combustion time proportion were affected by injection strategies by 3.8%,50%,and 19.7%,respectively.Split pre-injection increased CH_(4) emission in the exhaust.Split post-injection,especially split post-injection of PD and NG,reduced the unburned CH_(4) emission by approximately 30%.When the split post-injection ratio was less than 30%,the trade-off between NO_(X) and soot was interrupted.The distribution range of hydroxyl radicals was expanded by pre-injection,and NO_(X) was generated in the region where the NG jet hit the wall.This paper provides valuable insights into the optimization of HPDI injection parameters.展开更多
This study aimed to investigate the impact of administration routes in establishing the Adriamycin(ADR)-induced chronic kidney disease(CKD)model.Using BALB/c mice,we compared the effects of conventional tail-vein inje...This study aimed to investigate the impact of administration routes in establishing the Adriamycin(ADR)-induced chronic kidney disease(CKD)model.Using BALB/c mice,we compared the effects of conventional tail-vein injection(TV10,10 mg/kg)to those of retro-orbital sinus(orbital vein)injection(OV10,10 mg/kg;OV8,8 mg/kg).The re-sults indicated that the OV10 group exhibited CKD pathology similar to the TV10 group,with both groups demonstrating significantly higher urinary albumin/creatinine ratio(p<0.05),tubular injury(p<0.05),and degree of renal fibrosis(p<0.05)than the OV8 group.No significant differences were observed between the OV10 and TV10 groups in urinary albumin/creatinine ratio,tubular injury,and degree of renal fibrosis.These findings demonstrated that retro-orbital administration of 10 mg/kg ADR in-duces comparable effects to conventional tail-vein administration.This technique's technical simplicity may improve experimental efficiency,reproducibility,and animal welfare in CKD research.In conclusion,this study validates the utility of retro-orbital injection in CKD model establishment,demonstrating its potential to standardize and improve the reliability of future CKD research protocols.展开更多
One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effect...One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effective alternative to significantly reduce these emissions.In this study,rapeseed methyl ester(RME)was used as a diesel engine fuel and the emitted particulate matter was comparedwith ultra-lowsulfur diesel(ULSD).Inmost experimental studies,the emission of soot wasmeasured.In this work,the effects of injection timing,injection pressure(IP),and engine load on fine particulate matter in both nucleation and accumulation modes were studied.The results show that IP increases the number of particles in the accumulation mode while the number of particles in the crystallization mode is higher for rapeseed methyl ester(RME)than for ultra-low sulfur diesel(ULSD).Conversely,the formation rates of particles in the accumulationmode are higher for ULSD.Cumulative concentration numbers(CCN)are generally higher for RME in crystallization mode but higher for ULSD in accumulation mode.Increasing the IP reduces the CCN values.The particle size in crystallizationmode reaches a maximum of 22 nm at IPs of 800 and 1000 bar but decreases to 15 nm at 1200 bar.Most fine particles fall in the 5–100 nm diameter range.High engine loads reduce the particle size distribution in nucleationmode for both fuels,with a slight increase in particle size in nucleationmode.Thestudy concluded that the use of rapeseed methyl ester as an engine fuel benefits the environment and improves air quality due to the significant reduction in the size,number,and concentration of nano-soot particles and total particles emitted from the engine.展开更多
Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive da...Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive data vulnerable to unauthorized access and misuse.With the exponential growth of digital data,robust security measures are essential.Data encryption,a widely used approach,ensures data confidentiality by making it unreadable and unalterable through secret key control.Despite their individual benefits,both require significant computational resources.Additionally,performing them separately for the same data increases complexity and processing time.Recognizing the need for integrated approaches that balance compression ratios and security levels,this research proposes an integrated data compression and encryption algorithm,named IDCE,for enhanced security and efficiency.Thealgorithmoperates on 128-bit block sizes and a 256-bit secret key length.It combines Huffman coding for compression and a Tent map for encryption.Additionally,an iterative Arnold cat map further enhances cryptographic confusion properties.Experimental analysis validates the effectiveness of the proposed algorithm,showcasing competitive performance in terms of compression ratio,security,and overall efficiency when compared to prior algorithms in the field.展开更多
Wen-lin Gong1,Chuang Sha2,Gang Du1,Zhong-gui Shan3,Zhong-quan Qi3,Su-fang Zhou1,Nuo Yang1,4,Yong-xiang Zhao1,4.First published:21 June 2017;10(5):454-460.DOI:10.1016/j.apjtm.2017.05.004 The authors would like to corre...Wen-lin Gong1,Chuang Sha2,Gang Du1,Zhong-gui Shan3,Zhong-quan Qi3,Su-fang Zhou1,Nuo Yang1,4,Yong-xiang Zhao1,4.First published:21 June 2017;10(5):454-460.DOI:10.1016/j.apjtm.2017.05.004 The authors would like to correct an error in Figure 3 in which the flow cytometric scattergram of CD4/CD44 for the control group was erroneously used for the scattergram of CD8/CD44 for the PVIDSC group.The correct scattergram of CD8/CD44 for the PVIDSC group is provided below.The error does not affect the conclusion of the study.The authors apologize for the error and the inconvenience it might have caused to readers.展开更多
Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propo...Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propofol injection pain(PIP) is well-known in the operating room and is commonly countered by the prophylactic administration of lidocaine.In anesthesia,PIP is encountered in 28%–90% of patients.^([4,5]) However,PIPprophylaxis does not seem to be efficacious in every population.^([6,7]) Whether procedural sedation and analgesia(PSA) in the emergency department(ED) warrants lidocaine administration is unclear.展开更多
Subcutaneous administration of low-molecularweight heparin(LMWH)has been widely accepted as an effective anticoagulation therapy and is frequently used for patients to prevent thromboembolic events.While the usually s...Subcutaneous administration of low-molecularweight heparin(LMWH)has been widely accepted as an effective anticoagulation therapy and is frequently used for patients to prevent thromboembolic events.While the usually seen bruising around the injection site during subcutaneous LMWH treatment,the abdominal wall(AW)hematoma(AWH)was scarcely observed and reported.A previous study demonstrated the usual etiological risk of AWH involved anticoagulation therapy,chronic kidney disease,and trauma.^([1])Most of these cases had a favorable prognosis after conservative treatment.展开更多
A series of experiments and numerical simulations are carried out in a high-speed axial compressor to systematically investigate the influence and underlying flow mechanisms of micro tip injection on enhancing compres...A series of experiments and numerical simulations are carried out in a high-speed axial compressor to systematically investigate the influence and underlying flow mechanisms of micro tip injection on enhancing compressor stability.Different geometric structures of micro tip injection have been investigated,including the axial positions of injector port,injected mass flow rate and injector diameter.First,seven designed micro tip injection structures and one solid wall casing are tested in the compressor test rig to elucidate the influence of different micro tip injection parameters on the compressor stability.Then,numerical simulations are conducted to analyze the underlying flow mechanisms of micro tip injection with different design parameters on enhancing the compressor stability.The experimental and numerical investigation reveal that when the injection port is located upstream of the low-speed region,the compressor stability is significantly enhanced.The tip injection with larger injected mass flow can obtain higher stall margin improvement.Smaller injector diameter produces higher injection momentum and velocity,contributing to greater improvement on the compressor stability.展开更多
BACKGROUND The accuracy of blind intra-articular injections in the shoulder is rather low.Inaccurate injections tend to lead to poorer treatment outcomes.The“Delaware posterior bone touch technique”has shown higher ...BACKGROUND The accuracy of blind intra-articular injections in the shoulder is rather low.Inaccurate injections tend to lead to poorer treatment outcomes.The“Delaware posterior bone touch technique”has shown higher accuracy in young,slender,healthy volunteers than the classical“Cyriax technique”.AIM To investigate whether the Delaware technique would also be more accurate in older patients with capsulitis.METHODS We analyzed the files of 100 consecutive patients with capsulitis who were treated with an intra-articular injection containing a mixture of triamcinolone,lidocaine,and air.After the injection,the shoulder was moved to determine whether a squishing sound could be produced.The squishing sound was interpreted as an accurate injection.The scores with the new Delaware technique were compared against those with the Cyriax technique in a previous study.RESULTS Squishing was heard after 87%of the injections.This was 13%(10%points)more than the 77%in the previous study(P=0.004).CONCLUSION The Delaware technique was significantly more accurate than the Cyriax technique also in middle aged patients with capsulitis.We hypothesize that the difference is caused by a lower risk that a part of the opening of the needle is still outside the capsule.展开更多
The long-term stability of CO_(2) storage represents a pivotal challenge in geological CO_(2) storage(CGS),particularly within deep saline aquifers characterized by complex fault-block systems.While the injection site...The long-term stability of CO_(2) storage represents a pivotal challenge in geological CO_(2) storage(CGS),particularly within deep saline aquifers characterized by complex fault-block systems.While the injection sites and rate under different fault structures will directly affect the CO_(2) storage effect and the risk of leakage.This study investigates the Gaoyou Sag in the Subei Basin,a representative fault-block reservoir,through an integrated numerical-experimental approach.A three-dimensional simulation model incorporating multiphase flow dynamics was developed to characterize subsurface CO_(2) transport and dissolution processes.A novel fault seal capacity evaluation framework was proposed,integrating three critical geological indices(fault throw/reservoir thickness/caprock thicknesses)with the coupling of formation physical properties,temperature,and pressure for the rational selection of injection sites and rates.The results show that Optimal storage performance is observed when the fault throw is lower than the reservoir and caprock thicknesses.Furthermore,higher temperature and pressure promote the dissolution and diffusion of CO_(2),while compared to the structural form of faults,the physical properties of faults have a more significant effect on CO_(2) leakage.The larger reservoir space and the presence of an interlayer reduce the risk of CO_(2) leakage,and augmenting storage potential.Decreasing the injection rate increases the proportion of dissolved CO_(2),thereby enhancing the safety of CO_(2) storage.展开更多
The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Ma...The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Mach numbers remains uncertain.Therefore,a comparativestudy was conducted using numerical methods to explore multi-cavity Scramjet combustor perfor-mance at a flight Mach number 7.0 with different injection positions.The combustor is equippedwith 6 cavities arranged in three groups along the flow direction,each consisting of two cavities per-pendicular to the flow.It is shown that the injection location significantly influences combustionperformance:Front-injection yields higher combustion efficiency than post-injection,but post-injection is advantageous for the intake start.Additionally,regardless of injection positions,themainstream flow state near the cavities behind the injection can be categorized as supersonic flow,supersonic-subsonic coexistence flow,and subsonic flow.The optimal length from the downstreamto the trailing edge of the cavities behind the injection for achieving maximum combustion effi-ciency is determined.Further extension beyond this optimal length does not significantly increasethe combustion efficiency.In addition,the optimal length varies with different injection positions-specifically,it is about 60%longer with post-injection conditions than with front-injection con-ditions in this investigation.Moreover,significant secondary combustion within the cavities leadingto improved efficiency only occurs when mainstream flow state is either supersonic flow orsupersonic-subsonic coexistence flow.Also,with a well-optimized design,the kerosene-fueledmulti-cavity Scramjet can achieve enhanced combustion efficiency,which shows relatively smallvariation across a wide range of equivalence ratios.This might be caused by the effects of interac-tion among these multiple cavities.Therefore,these research findings can provide valuable insightsfor designing and optimizing the kerosene-fueled multi-cavity combustor in Scramjet at high Machnumbers.展开更多
BACKGROUND Intra-articular hip injections(IAHIs)are commonly used for diagnostic and therapeutic purposes but are often associated with patient anxiety and fear.The disparity between anticipated and experienced pain d...BACKGROUND Intra-articular hip injections(IAHIs)are commonly used for diagnostic and therapeutic purposes but are often associated with patient anxiety and fear.The disparity between anticipated and experienced pain during IAHIs and the role of preinjection local anesthesia in pain modulation remains unclear.AIM To investigate the difference between anticipated and experienced pain during IAHIs and the impact of pre-injection local anesthesia.METHODS This prospective study enrolled 60 patients undergoing IAHI,30 receiving pre-injection superficial local anesthesia and 30 serving as a control group without pre-injection local anesthesia.Pain levels were assessed using numeric rating scales.RESULTS Patients significantly overestimated anticipated pain compared to experienced pain(6.43±2.48 vs 3.68±2.37,P<0.001).Pre-injection local anesthesia did not significantly reduce experienced pain(3.19±2.38 vs 4.20±2.29,P=0.130).CONCLUSION Patients overestimate anticipated pain during IAHIs.Pre-injection local anesthesia does not reduce experienced pain.展开更多
With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored ha...With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored has increased dramatically. The use of compression techniques for these bitstream files is emerging as a key strategy to alleviate the burden on storage resources. Due to the severe resource constraints of space-based electronics and the unique application environment, the simplicity, efficiency and robustness of the decompression circuitry is also a key design consideration. Through comparative analysis current bitstream file compression technologies, this research suggests that the Lempel Ziv Oberhumer (LZO) compression algorithm is more suitable for satellite applications. This paper also delves into the compression process and format of the LZO compression algorithm, as well as the inherent characteristics of configuration bitstream files. We propose an improved algorithm based on LZO for bitstream file compression, which optimises the compression process by refining the format and reducing the offset. Furthermore, a low-cost, robust decompression hardware architecture is proposed based on this method. Experimental results show that the compression speed of the improved LZO algorithm is increased by 3%, the decompression hardware cost is reduced by approximately 60%, and the compression ratio is slightly reduced by 0.47%.展开更多
文摘BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good.
基金supported by Basic and Applied Basic research foundation of Guangdong province(Nos.2021A1515010343 and 2022A1515011582)the Science and Technology Program of Guangdong Province(Nos.2021A0505030026 and 2022A0505050029).
文摘In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-based alloy(typically pure lead or lead-bismuth eutectic(LBE))is used as the coolant.To clarify the pressure build-up characteristics under water-jet injection,this study conducted several experiments by injecting pressurized water into a molten LBE pool at Sun Yat-sen University.To obtain a further understanding,several new experimental parameters were adopted,including the melt temperature,water subcooling,injection pressure,injection duration,and nozzle diameter.Through detailed analyses,it was found that the pressure and temperature during the water-melt interaction exhibited a consistent variation trend with our previous water-droplet injection mode LBE experiment.Similarly,the existence of a steam explosion was confirmed,which typically results in a much stronger pressure build-up.For the non-explosion cases,increasing the injection pressure,melt-pool temperature,nozzle diameter,and water subcooling promoted pressure build-up in the melt pool.However,a limited enhancement effect was observed when increasing the injection duration,which may be owing to the continually rising pressure in the interaction vessel or the isolation effect of the generated steam cavity.Regardless of whether a steam explosion occurred,the calculated mechanical and kinetic energy conversion efficiencies of the melt were relatively small(not exceeding 4.1%and 0.7%,respectively).Moreover,the range of the conversion efficiency was similar to that of previous water-droplet experiments,although the upper limit of the jet mode was slightly lower.
基金Supported by The New Faculty Research Grant of Pusan National University,2023The Research Grant of the Chungbuk National University in 2023.
文摘BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resolve,several treatment options have been suggested for this condition.CASE SUMMARY In this paper,we report a case of corticosteroid injection induced lipoatrophy treated with autologous whole blood(AWB)injection,as the condition had been unresponsive to fractional laser therapy.A 29-year-old female patient visited the dermatology clinic complaining of skin depression on her right buttock area,which had appeared six months earlier.There had been only subtle improvement at the margins after fractional CO_(2) laser treatment;therefore,after obtaining informed consent from the patient,AWB treatment was initiated.One month after the first AWB injection,the size and depth of the lesion had noticeably improved,and a slight improvement was also observed in discoloration.CONCLUSION Close observation is the initial treatment of choice for steroid induced skin atrophy;however,for patients in need of immediate cosmetic improvement,AWB injection may be a safe and cost-effective alternative.
基金supported by the National Natural Science Foundation of China(Grant Nos.42372312,and 42172299)the Pyramid Talent Training Project of Beijing University of Civil Engineering and Architecture(Grant No.JDYC20220807).
文摘The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics of frozen sodium sulfate saline sandy soil,a series of uniaxial compression tests were performed by integrating digital image correlation(DIC)technology into the testing apparatus.The evolution law of the uniaxial compression strength(UCS),the failure strain,and the formation of the shear band of the frozen sodium sulfate saline sandy soil were analyzed.The test results show that within the scope of this study,with the increase of salt content,both the UCS and the shear band angle initially decrease with increasing salt content before showing an increase.In contrast,the failure strain and the width of the shear band exhibit an initial increase followed by a decrease in the samples.In addition,to investigate the brittle failure characteristics of frozen sodium sulfate saline sandy soil,two classic brittleness evaluation methods were employed to quantitatively assess the brittleness level for the soil samples.The findings suggest that the failure characteristics under all test conditions in this study belong to the transition stage between brittle and ductile,indicating that frozen sodium sulfate saline sandy soil exhibits certain brittle behavior under uniaxial compression conditions,and the brittleness index basically decreases and then increases with the rise in salt content.
基金National Natural Science Foundation of China(52305349)Heilongjiang Touyan Team(HITTY-20190036)+2 种基金Heilongjiang Provincial Natural Science Foundation of China(LH2023E033)CGN-HIT Advanced Nuclear and New Energy Research Institute(CGN-HIT202305)Natural Science Basic Research Program of Shaanxi Province(2023-JC-QN-0518)。
文摘The effect of deformation resistance of AlCr_(1.3)TiNi_(2) eutectic high-entropy alloys under various current densities and strain rates was investigated during electrically-assisted compression.Results show that at current density of 60 A/mm^(2) and strain rate of 0.1 s^(−1),the ultimate tensile stress shows a significant decrease from approximately 3000 MPa to 1900 MPa with reduction ratio of about 36.7%.However,as current density increases,elongation decreases due to intermediate temperature embrittlement.This is because the current induces Joule effect,which then leads to stress concentration and more defect formation.Moreover,the flow stress is decreased with the increase in strain rate at constant current density.
基金financially supported by the National Natural Science Foundation of China(Nos.52174092,51904290,and 52374147)the Natural Science Foundation of Jiangsu Province,China(No.BK20220157)+2 种基金the Fundamental Research Funds for the Central Universities,China(No.2022YCPY0202)the National Key Research and Development Program of China(No.2023YFC3804204)the Major Program of Xinjiang Uygur Autonomous Region S cience and Technology(No.2023A01002)。
文摘The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.
文摘Chronic migraine is a potentially debilitating condition that can be detrimental to someone’s quality of life. Clinical data has proven OnabotulinumtoxinA (BoNT-A) to be an effective prophylactic treatment for chronic headache types, and it is now regularly employed by headache treatment centers. The PREEMPT injection protocol has become the standard treatment regimen surrounding Botox injections for chronic migraine treatment since it was granted approval by the FDA in 2010. This retrospective chart review of patients treated for chronic migraine at Maine Comprehensive Pain Management in Scarborough, Maine, presents an alteration to the standard PREEMPT injection paradigm that reinforces the efficacy of Botox for chronic migraine treatment. We will discuss our Modified PREEMPT injection paradigm, which yields a positive clinical response rate of 95% of patients achieving at least 50% improvement in their migraine headaches. This appears to be the highest established response rate in the literature to date.
基金Supported by the National Natural Science Foundation of China(No.51909154)Shanghai Engineering Research Center of Ship Intelligent Maintenance and Energy Efficiency(No.20DZ2252300).
文摘Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG high pressure direct injection(HPDI)engine are examined.Four typical split injection strategies,namely split pre-injection of pilot diesel(PD)and NG,split post-injection of PD and NG,split pre-injection of NG,and split post-injection of PD,were developed to investigate the influences on combustion and emissions.Results revealed that split pre injection of NG enhanced the atomization of PD,whereas the split post-injection of NG lowered the temperature in the core region of the PD spray,resulting in the deterioration of combustion.The effect of the split injection strategy on indicated thermal efficiency exceeded 7.5%.Split pre-injection was favorable to enhancing thermal efficiency,whereas split post-injection was not.Ignition delay,combustion duration,and premixed combustion time proportion were affected by injection strategies by 3.8%,50%,and 19.7%,respectively.Split pre-injection increased CH_(4) emission in the exhaust.Split post-injection,especially split post-injection of PD and NG,reduced the unburned CH_(4) emission by approximately 30%.When the split post-injection ratio was less than 30%,the trade-off between NO_(X) and soot was interrupted.The distribution range of hydroxyl radicals was expanded by pre-injection,and NO_(X) was generated in the region where the NG jet hit the wall.This paper provides valuable insights into the optimization of HPDI injection parameters.
文摘This study aimed to investigate the impact of administration routes in establishing the Adriamycin(ADR)-induced chronic kidney disease(CKD)model.Using BALB/c mice,we compared the effects of conventional tail-vein injection(TV10,10 mg/kg)to those of retro-orbital sinus(orbital vein)injection(OV10,10 mg/kg;OV8,8 mg/kg).The re-sults indicated that the OV10 group exhibited CKD pathology similar to the TV10 group,with both groups demonstrating significantly higher urinary albumin/creatinine ratio(p<0.05),tubular injury(p<0.05),and degree of renal fibrosis(p<0.05)than the OV8 group.No significant differences were observed between the OV10 and TV10 groups in urinary albumin/creatinine ratio,tubular injury,and degree of renal fibrosis.These findings demonstrated that retro-orbital administration of 10 mg/kg ADR in-duces comparable effects to conventional tail-vein administration.This technique's technical simplicity may improve experimental efficiency,reproducibility,and animal welfare in CKD research.In conclusion,this study validates the utility of retro-orbital injection in CKD model establishment,demonstrating its potential to standardize and improve the reliability of future CKD research protocols.
文摘One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effective alternative to significantly reduce these emissions.In this study,rapeseed methyl ester(RME)was used as a diesel engine fuel and the emitted particulate matter was comparedwith ultra-lowsulfur diesel(ULSD).Inmost experimental studies,the emission of soot wasmeasured.In this work,the effects of injection timing,injection pressure(IP),and engine load on fine particulate matter in both nucleation and accumulation modes were studied.The results show that IP increases the number of particles in the accumulation mode while the number of particles in the crystallization mode is higher for rapeseed methyl ester(RME)than for ultra-low sulfur diesel(ULSD).Conversely,the formation rates of particles in the accumulationmode are higher for ULSD.Cumulative concentration numbers(CCN)are generally higher for RME in crystallization mode but higher for ULSD in accumulation mode.Increasing the IP reduces the CCN values.The particle size in crystallizationmode reaches a maximum of 22 nm at IPs of 800 and 1000 bar but decreases to 15 nm at 1200 bar.Most fine particles fall in the 5–100 nm diameter range.High engine loads reduce the particle size distribution in nucleationmode for both fuels,with a slight increase in particle size in nucleationmode.Thestudy concluded that the use of rapeseed methyl ester as an engine fuel benefits the environment and improves air quality due to the significant reduction in the size,number,and concentration of nano-soot particles and total particles emitted from the engine.
基金the Deanship of Graduate Studies and Scientific Research at Qassim University for financial support(QU-APC-2025).
文摘Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive data vulnerable to unauthorized access and misuse.With the exponential growth of digital data,robust security measures are essential.Data encryption,a widely used approach,ensures data confidentiality by making it unreadable and unalterable through secret key control.Despite their individual benefits,both require significant computational resources.Additionally,performing them separately for the same data increases complexity and processing time.Recognizing the need for integrated approaches that balance compression ratios and security levels,this research proposes an integrated data compression and encryption algorithm,named IDCE,for enhanced security and efficiency.Thealgorithmoperates on 128-bit block sizes and a 256-bit secret key length.It combines Huffman coding for compression and a Tent map for encryption.Additionally,an iterative Arnold cat map further enhances cryptographic confusion properties.Experimental analysis validates the effectiveness of the proposed algorithm,showcasing competitive performance in terms of compression ratio,security,and overall efficiency when compared to prior algorithms in the field.
文摘Wen-lin Gong1,Chuang Sha2,Gang Du1,Zhong-gui Shan3,Zhong-quan Qi3,Su-fang Zhou1,Nuo Yang1,4,Yong-xiang Zhao1,4.First published:21 June 2017;10(5):454-460.DOI:10.1016/j.apjtm.2017.05.004 The authors would like to correct an error in Figure 3 in which the flow cytometric scattergram of CD4/CD44 for the control group was erroneously used for the scattergram of CD8/CD44 for the PVIDSC group.The correct scattergram of CD8/CD44 for the PVIDSC group is provided below.The error does not affect the conclusion of the study.The authors apologize for the error and the inconvenience it might have caused to readers.
文摘Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propofol injection pain(PIP) is well-known in the operating room and is commonly countered by the prophylactic administration of lidocaine.In anesthesia,PIP is encountered in 28%–90% of patients.^([4,5]) However,PIPprophylaxis does not seem to be efficacious in every population.^([6,7]) Whether procedural sedation and analgesia(PSA) in the emergency department(ED) warrants lidocaine administration is unclear.
文摘Subcutaneous administration of low-molecularweight heparin(LMWH)has been widely accepted as an effective anticoagulation therapy and is frequently used for patients to prevent thromboembolic events.While the usually seen bruising around the injection site during subcutaneous LMWH treatment,the abdominal wall(AW)hematoma(AWH)was scarcely observed and reported.A previous study demonstrated the usual etiological risk of AWH involved anticoagulation therapy,chronic kidney disease,and trauma.^([1])Most of these cases had a favorable prognosis after conservative treatment.
基金supported by National Natural Science Foundation of China(No.52076179)National Science and Technology Major Projects of China(No.J2019-I-0011).
文摘A series of experiments and numerical simulations are carried out in a high-speed axial compressor to systematically investigate the influence and underlying flow mechanisms of micro tip injection on enhancing compressor stability.Different geometric structures of micro tip injection have been investigated,including the axial positions of injector port,injected mass flow rate and injector diameter.First,seven designed micro tip injection structures and one solid wall casing are tested in the compressor test rig to elucidate the influence of different micro tip injection parameters on the compressor stability.Then,numerical simulations are conducted to analyze the underlying flow mechanisms of micro tip injection with different design parameters on enhancing the compressor stability.The experimental and numerical investigation reveal that when the injection port is located upstream of the low-speed region,the compressor stability is significantly enhanced.The tip injection with larger injected mass flow can obtain higher stall margin improvement.Smaller injector diameter produces higher injection momentum and velocity,contributing to greater improvement on the compressor stability.
文摘BACKGROUND The accuracy of blind intra-articular injections in the shoulder is rather low.Inaccurate injections tend to lead to poorer treatment outcomes.The“Delaware posterior bone touch technique”has shown higher accuracy in young,slender,healthy volunteers than the classical“Cyriax technique”.AIM To investigate whether the Delaware technique would also be more accurate in older patients with capsulitis.METHODS We analyzed the files of 100 consecutive patients with capsulitis who were treated with an intra-articular injection containing a mixture of triamcinolone,lidocaine,and air.After the injection,the shoulder was moved to determine whether a squishing sound could be produced.The squishing sound was interpreted as an accurate injection.The scores with the new Delaware technique were compared against those with the Cyriax technique in a previous study.RESULTS Squishing was heard after 87%of the injections.This was 13%(10%points)more than the 77%in the previous study(P=0.004).CONCLUSION The Delaware technique was significantly more accurate than the Cyriax technique also in middle aged patients with capsulitis.We hypothesize that the difference is caused by a lower risk that a part of the opening of the needle is still outside the capsule.
基金the Beijing Natural Science Foundation(No.8232044)the Science Foundation of China University of Petroleum,Beijing(No.2462023BJRC030).
文摘The long-term stability of CO_(2) storage represents a pivotal challenge in geological CO_(2) storage(CGS),particularly within deep saline aquifers characterized by complex fault-block systems.While the injection sites and rate under different fault structures will directly affect the CO_(2) storage effect and the risk of leakage.This study investigates the Gaoyou Sag in the Subei Basin,a representative fault-block reservoir,through an integrated numerical-experimental approach.A three-dimensional simulation model incorporating multiphase flow dynamics was developed to characterize subsurface CO_(2) transport and dissolution processes.A novel fault seal capacity evaluation framework was proposed,integrating three critical geological indices(fault throw/reservoir thickness/caprock thicknesses)with the coupling of formation physical properties,temperature,and pressure for the rational selection of injection sites and rates.The results show that Optimal storage performance is observed when the fault throw is lower than the reservoir and caprock thicknesses.Furthermore,higher temperature and pressure promote the dissolution and diffusion of CO_(2),while compared to the structural form of faults,the physical properties of faults have a more significant effect on CO_(2) leakage.The larger reservoir space and the presence of an interlayer reduce the risk of CO_(2) leakage,and augmenting storage potential.Decreasing the injection rate increases the proportion of dissolved CO_(2),thereby enhancing the safety of CO_(2) storage.
基金financially supported by the National Key Laboratory of Ramjet,China(No.2022-020-003)the Fundamental Research Funds for the Central Universities,China(No.501QYZX2023146001)。
文摘The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Mach numbers remains uncertain.Therefore,a comparativestudy was conducted using numerical methods to explore multi-cavity Scramjet combustor perfor-mance at a flight Mach number 7.0 with different injection positions.The combustor is equippedwith 6 cavities arranged in three groups along the flow direction,each consisting of two cavities per-pendicular to the flow.It is shown that the injection location significantly influences combustionperformance:Front-injection yields higher combustion efficiency than post-injection,but post-injection is advantageous for the intake start.Additionally,regardless of injection positions,themainstream flow state near the cavities behind the injection can be categorized as supersonic flow,supersonic-subsonic coexistence flow,and subsonic flow.The optimal length from the downstreamto the trailing edge of the cavities behind the injection for achieving maximum combustion effi-ciency is determined.Further extension beyond this optimal length does not significantly increasethe combustion efficiency.In addition,the optimal length varies with different injection positions-specifically,it is about 60%longer with post-injection conditions than with front-injection con-ditions in this investigation.Moreover,significant secondary combustion within the cavities leadingto improved efficiency only occurs when mainstream flow state is either supersonic flow orsupersonic-subsonic coexistence flow.Also,with a well-optimized design,the kerosene-fueledmulti-cavity Scramjet can achieve enhanced combustion efficiency,which shows relatively smallvariation across a wide range of equivalence ratios.This might be caused by the effects of interac-tion among these multiple cavities.Therefore,these research findings can provide valuable insightsfor designing and optimizing the kerosene-fueled multi-cavity combustor in Scramjet at high Machnumbers.
基金approved by the Medical Ethics Committee of the Tel Aviv Sourasky Medical Center Institutional Review Board,approval No.TLV-0674-21.
文摘BACKGROUND Intra-articular hip injections(IAHIs)are commonly used for diagnostic and therapeutic purposes but are often associated with patient anxiety and fear.The disparity between anticipated and experienced pain during IAHIs and the role of preinjection local anesthesia in pain modulation remains unclear.AIM To investigate the difference between anticipated and experienced pain during IAHIs and the impact of pre-injection local anesthesia.METHODS This prospective study enrolled 60 patients undergoing IAHI,30 receiving pre-injection superficial local anesthesia and 30 serving as a control group without pre-injection local anesthesia.Pain levels were assessed using numeric rating scales.RESULTS Patients significantly overestimated anticipated pain compared to experienced pain(6.43±2.48 vs 3.68±2.37,P<0.001).Pre-injection local anesthesia did not significantly reduce experienced pain(3.19±2.38 vs 4.20±2.29,P=0.130).CONCLUSION Patients overestimate anticipated pain during IAHIs.Pre-injection local anesthesia does not reduce experienced pain.
基金supported in part by the National Key Laboratory of Science and Technology on Space Microwave(Grant Nos.HTKJ2022KL504009 and HTKJ2022KL5040010).
文摘With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored has increased dramatically. The use of compression techniques for these bitstream files is emerging as a key strategy to alleviate the burden on storage resources. Due to the severe resource constraints of space-based electronics and the unique application environment, the simplicity, efficiency and robustness of the decompression circuitry is also a key design consideration. Through comparative analysis current bitstream file compression technologies, this research suggests that the Lempel Ziv Oberhumer (LZO) compression algorithm is more suitable for satellite applications. This paper also delves into the compression process and format of the LZO compression algorithm, as well as the inherent characteristics of configuration bitstream files. We propose an improved algorithm based on LZO for bitstream file compression, which optimises the compression process by refining the format and reducing the offset. Furthermore, a low-cost, robust decompression hardware architecture is proposed based on this method. Experimental results show that the compression speed of the improved LZO algorithm is increased by 3%, the decompression hardware cost is reduced by approximately 60%, and the compression ratio is slightly reduced by 0.47%.