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Predicting the temperature of CRTS Ⅲ ballastless tracks in cold regions based on a TCN-Track model 认领 引用
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作者 Jie LIANG Shijie DENG +4 位作者 Juanjuan REN Wenlong YE Kaiyao ZHANG Dacheng LI Ronghe ZHANG 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2026年第1期43-57,共15页
The uneven distribution of the temperature field in the track structure,caused by various meteorological factors such as extremely low temperatures and snowfall,leads to significant temperature loads and is the primar... The uneven distribution of the temperature field in the track structure,caused by various meteorological factors such as extremely low temperatures and snowfall,leads to significant temperature loads and is the primary cause of damage to China Railway Track System(CRTS)Ⅲ ballastless tracks in cold regions during service.In this study,to predict the temperature of the track structure accurately,we analyzed meteorological data collected from Shenyang,China,and identified the factors that had the most effect on the track temperature field.We propose a temporal convolutional network(TCN)-based temperature field prediction model for ballastless tracks(TCN-Track model),which enhances the ability to extract and fuse local and global features from complex long-term meteorological data.The results indicate that the proposed TCN-Track model performs well in predicting track temperature fields from meteorological data,with a mean absolute error(MAE)ranging from 0.26 to 0.39,a root mean square error(RMSE)ranging from 0.32 to 0.50,and correlation coefficient(R)values ranging from 0.888 to 0.985.Compared with a long short-term memory(LSTM)model,the MAE of the TCN-Track model is reduced by 89.17%and the RMSE by 88.51%.This method offers a new solution for accurately predicting the temperature field of ballastless tracks in cold regions,aiding in predicting and preventing track damage caused by low temperatures. 展开更多
关键词 Cold regions CRTSⅢballastless tracks Temperature prediction Meteorological variables Time prediction model
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Influences of environmental factors on the microbial community characteristics of bioaerosols in a cold region 认领 引用
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作者 Nami Lai Shuozhen Tian +14 位作者 Silu Wang Xiaoyan Wang Ruihan Chen Yuwei Liu Huize Yang Mengying Wang Xiaoyu Cai Wanying Yao Shuling Li Yue Xiao Chunshuang Li Yue Han Chao Jiang Weiwei Song Jun Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第6期452-463,共12页
The frequent occurrence of respiratory diseases in winter populations underscores the need to understand environmental drivers of bioaerosols in cold regions for infection control.Our study revealed impacts of environ... The frequent occurrence of respiratory diseases in winter populations underscores the need to understand environmental drivers of bioaerosols in cold regions for infection control.Our study revealed impacts of environmental factors on airborne microbial communities in a typical Northeast China megacity(-25 to 0℃).Bioaerosols originated from anthropogenic activities(coal combustion,agricultural biomass burning),natural sources(soil resuspension),and long-range transport.Some pathogenic genera showed significant negative correlations with particles/T/O3.RDA and CCA analysis indicated O3,RH,SO2and T dominated bacterial genera structure,and O3,PM2.5,and PM2.5–10 played more significant roles in fungal genera structure.O3imposed oxidative damage on most genera.Bacterial abundances responded to RH/SO2/T due to secondary aerosol formation/coal burning emission source/enzymatic controls,respectively.And fungal significantly positive correlations of Alternaria-PM2.5and Mortierella-PM2.5–10 were attributed to similar sources of fungal genera and pollutants,namely agricultural residue burning,and dust,respectively.PM2.5,NO2,and CO were determined as dominant factors for the alpha diversity of bacteria communities.For fungi community,PM2.5–10 and SO2were dominant factors influencing its alpha diversity.Co-occurrence networks indicated intensified bacterial competition and more various bacterial sources with rising PM2.5,T,NO2,and CO.And there were competitive fungal interactions with more various fungal sources under elevated pollutants and declining RH.These findings elucidate pollution-bioaerosol linkages in cold urban air,providing amechanistic basis for controlling microbial community especially pathogens in sub-zero environments amid climate change. 展开更多
关键词 Cold regions Bioaerosols PM2.5 Low ambient temperature Bacteria Fungi
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Challenges and optimization of prenatal diagnosis in cold regions:Combined application of karyotyping and CNV-Seq with seasonal compliance analysis 认领 引用
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作者 Luyao Liu Yuhong Zhang +3 位作者 Yitong Wang Kai Zheng Hao Wang Ying Wang 《Frigid Zone Medicine》 2026年第2期109-116,共8页
Objective:Prenatal diagnosis in cold regions faces distinctive challenges related to extreme cold climatic conditions,which can substantially reduce healthcare compliance among pregnant women and limit the accessibili... Objective:Prenatal diagnosis in cold regions faces distinctive challenges related to extreme cold climatic conditions,which can substantially reduce healthcare compliance among pregnant women and limit the accessibility and accuracy of local prenatal diagnostic services.However,targeted research on region-specific diagnostic barriers and optimized combined detection strategies remains insufficient.This study systematically investigated the unique challenges of prenatal diagnosis in cold regions,with particular emphasis on the impact of harsh climatic conditions on healthcare compliance among pregnant women and evaluated the clinical utility of integrating chromosomal karyotyping with copy number variation sequencing(CNV-seq).Methods:A retrospective analysis was conducted among high-risk pregnant women over a two-year period.Seasonal differences in prenatal clinic attendance were statistically analyzed to identify key barriers affecting healthcare compliance.Additionally,the clinical efficacy of combined chromosomal karyotyping and CNV-seq was systematically evaluated.Results:Retrospective analysis of high-risk pregnancies revealed a statistically significant decline in winter clinic attendance(χ2=9.51,P<0.05)over the two-year period,mainly associated with transportation difficulties,concerns regarding nosocomial infection,and local cultural practices.The combined use of chromosomal karyotyping and CNV-seq demonstrated complementary diagnostic value.Karyotyping identified 12 balanced translocations,23 sex chromosome aneuploidies,and 29 chromosomal polymorphic variants,while CNV-seq detected 19 pathogenic or likely pathogenic microdeletions/microduplications,including 16 pathogenic variants.Together,the two methods increased the overall abnormality detection rate to 18.64%(118/633),representing a 7.42%improvement over single-method detection strategies.Conclusions:Based on these findings,several regionally optimized strategies are proposed,including the establishment of a"central laboratory+satellite clinics"network,the promotion of non-invasive prenatal testing(NIPT)combined with first-trimester ultrasound screening to reduce unnecessary invasive procedures,and improved management of high-risk pregnancies through tele-genetic counseling,winter green-channel services,and vitamin D supplementation.This study provides both theoretical and practical frameworks for improving the precision,accessibility,and equity of prenatal diagnostic systems in cold regions. 展开更多
关键词 cold regions combined detection strategies seasonal differences prenatal diagnosis prenatal diagnostic CNV seq healthcare compliance chromosomal karyotyping
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Association between ambient temperature variability and ST-segment elevation myocardial infarction in cold regions,China:A time-series analysis 认领 引用
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作者 Sizheng Peng Kai Du +9 位作者 Hongyan Zhao Yingtao Zhang Ruiyi Chen Haiyu Zhang Kai Dong Hongxin Xu Yue Li Leilei Yin Yuhui Sun Tao Song 《Frigid Zone Medicine》 2026年第2期65-75,共11页
Objective:This study investigated the impact of daily ambient temperature and temperature changes between neighboring days(TCN)on the risk of ST-segment elevation myocardial infarction(STEMI)in cold regions using a ti... Objective:This study investigated the impact of daily ambient temperature and temperature changes between neighboring days(TCN)on the risk of ST-segment elevation myocardial infarction(STEMI)in cold regions using a time-series approach.Methods:From January 1,2017 to December 31,2020,STEMI cases were collected from the largest medical center in Heilongjiang Province,excluding patients with incomplete data or unclear symptom onset times.Meteorological variables and air pollutant data corresponding to patients'residential address were matched from nearby monitoring stations.A distributed lag nonlinear model(DLNM)with a lag period of 0-21 days was applied to assess the effects of suboptimal temperatures on STEMI risk and lag structures.Different temperature indicators(maximum,mean,minimum,and TCN)were compared,and subgroup analyses by sex and age were performed to evaluate population-specific susceptibility.Results:A total of 1461 days were included,comprising 4700 STEMI cases.Cold exposure was associated with a significant increase in STEMI incidence,with a delayed onset of 3 days and a prolonged effect lasting up to 20 days.In contrast,the heat effect was immediate and persisted for approximately 3 days.In the 21-day cumulative relative risk(CRR)analysis,using a median temperature of 6.6℃,the minimum morbidity temperature was identified at 17℃(CRR 0.709,95%CI 0.345-1.457).Notably,the highest incidence did not occur at the lowest temperature(-29℃,CRR 1.201,95%CI 0.273-5.273).Instead,STEMI risk increased as temperatures rose from extreme cold,reaching a peak at-10℃(CRR 1.63,95%CI 0.905-2.936).Under conditions of extreme cooling(TCN=-11℃),STEMI risk increased from lag 0 to 7(relative risk[RR]2.239,95%CI 0.279-17.936).Conclusions:In cold regions,extreme temperatures,especially sustained cold exposure,significantly increase the risk of STEMI.Rapid temperature drops between consecutive days further elevate incidence,highlighting the importance of both absolute temperature and short-term temperature variability in cardiovascular risk. 展开更多
关键词 st segment elevation myocardial infarction cold regions air pollutant data ambient temperature distributed lag nonlinear model temperature variability time series analysis cardiovascular risk
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Effect of temperature and water content on surface albedo of loess in cold regions and the associated mechanisms 认领 引用
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作者 MA Anjing ZHANG Mingli +3 位作者 ZHOU Fengxi ZHOU Zhixiong FENG Wei WANG Zhen 《Journal of Mountain Science》 SCIE CSCD 2025年第4期1306-1325,共20页
Surface albedo,as one of the important properties of the underlying surface,has a significant impact on the surface energy balance in cold regions.However,due to the complexity of the factors affecting surface albedo,... Surface albedo,as one of the important properties of the underlying surface,has a significant impact on the surface energy balance in cold regions.However,due to the complexity of the factors affecting surface albedo,existing calculations still contain inaccuracies.Therefore,this study conducted surface albedo experiments on loess with different water contents and temperatures.By analyzing the surface albedo measurements of samples with varying temperature and water content levels,as well as the soil freezing characteristic curve(SFCC)and soil-water characteristic curve(SWCC)of loess,the study explores the influence of soil temperature and water content on the surface albedo of loess.The results indicate that both the temperature and water content of loess jointly affect surface albedo.During the process of albedo change,there exists a water content threshold that alters the trend of surface albedo.Soil temperature influences surface albedo by affecting the content of pore ice and liquid water within the soil.When the water content of loess is relatively low,the surface albedo decreases as the unfrozen water content decreases.However,this trend changes as the water content of loess increases.Additionally,a decrease in soil temperature lowers the moisture content threshold during the changes in surface albedo.This study provides a reference for exploring and determining the surface energy balance in cold regions under the background of warm and humid climates,as well as for establishing thermal calculation boundaries. 展开更多
关键词 Loess Cold regions Surface albedo Water content Soil temperature
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Study on Optimization of Two-Stage Phase Change Heat Storage Coupled Solar-Air Source Heat Pump Heating System in Severe Cold Region 认领 引用
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作者 Xueli Wang Yan Jia Degong Zuo 《Energy Engineering》 EI 2025年第4期1603-1627,共25页
The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions.This research designs a novel two-stage phase change heat storage coupled solar-... The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions.This research designs a novel two-stage phase change heat storage coupled solar-air source heat pump heating system structure that is specifically designed for such regions.The two-stage heat storage device in this heating system expands the storage temperature range of solar heat.The utilization of the two-stage heat storage device not onlymakes up for the instability of the solar heating system,but can also directlymeet the building heating temperature,and can reduce the influence of low-temperature outdoor environments in severe cold regions on the heating performance of the air source heat pump by using solar energy.Therefore,the two-stage phase change heat storage coupled to the solar energy-air source heat pump heating system effectively improves the utilization rate of solar energy.A numerical model of the system components and their integration was developed using TRNSYS software in this study,and various performance aspects of the system were simulated and analyzed.The simulation results demonstrated that the two-stage heat storage device can effectively store solar energy,enabling its hierarchical utilization.The low-temperature solar energy stored by the two-stage phase change heat storage device enhances the coefficient of performance of the air source heat pump by 11.1%in severe cold conditions.Using the Hooke-Jeeves optimization method,the annual cost and carbon emissions are taken as optimization objectives,with the optimized solar heat supply accounting for 52.5%.This study offers valuable insights into operational strategies and site selection for engineering applications,providing a solid theoretical foundation for the widespread implementation of this system in severe cold regions. 展开更多
关键词 Two-stage heat storage building heating Hooke-Jeeves optimization phase change heat storage device severe cold region
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Circular RNA signatures in vestibular migraine and migraine from cold regions:Preliminary mechanistic insights 认领 引用
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作者 Qihui Chen Jinghan Lin +2 位作者 Qingling Zhai Qijun Yu Yonghui Pan 《Frigid Zone Medicine》 2025年第4期193-205,共13页
Background:Vestibular migraine(VM)is a common disorder characterized by recurrent dizziness or vertigo,often aggravated by cold exposure.This study aimed to identify differentially expressed circular RNAs(circRNAs)in ... Background:Vestibular migraine(VM)is a common disorder characterized by recurrent dizziness or vertigo,often aggravated by cold exposure.This study aimed to identify differentially expressed circular RNAs(circRNAs)in cold-region VM and explore the underlying molecular mechanisms.Methods:Peripheral blood samples from long-term residents of Heilongjiang Province profiled by circRNA microarray,and differentially expressed circRNAs were validated by quantitative reverse transcription polymerase chain reaction(qRT-PCR).A competing endogenous RNA(ceRNA)network and enriched pathways were inferred by bioinformatics.A VM-like mouse model was established using nitroglycerin(NTG)and kainic acid(KA)and confirmed by behavioral testing and western blot.The hsa_circ_0003201/miR-31-5priggering receptor expressed on myeloid cells 2(TREM2)axis and related pathways were examined in clinical samples and in the trigeminal nucleus caudalis(TNC)and vestibular nuclei(VN)of mice using qRT-PCR,enzyme-linked immunosorbent assay(ELISA),and western blot.CircRNA microarray profiling also compared expression patterns between VM and migraine patients.Results:Hsa_circ_0003201 was significantly upregulated in cold-region VM patients.Bioinformatic analyses revealed that hsa_circ_0003201 may regulate the miR-31-5p/TREM2 axis and be associated with phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling,pyruvate metabolism,and transient receptor potential(TRP)pathways.Clinical validation confirmed increased hsa_circ_0003201 and TREM2 and decreased miR-31-5p.VM-like mice exhibited central sensitization and vestibular dysfunction,with increased TREM2,decreased miR-31-5p,and PI3K/AKT activation in the TNC and VN.Comparative circRNA analysis between VM and migraine patients indicated distinct expression patterns.Conclusion:Hsa_circ_0003201 shows potential as a diagnostic biomarker for cold-region VM,and the hsa_circ_0003201/miR-31-5p/TREM2 axis may contribute to pathogenesis through PI3K/AKT signaling,pyruvate metabolism,and TRP-related pathways. 展开更多
关键词 circRNA vestibular migraine cold regions
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Prognostic value of combined lymphocyte-to-monocyte ratio and cancer antigen 724 in patients with proximal gastric cancer residing in extremely cold regions 认领 引用
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作者 Xiqing Zhu Dali Li +2 位作者 Shanshan Liang Huaxing Wu Haibin Song 《Frigid Zone Medicine》 2025年第3期170-179,共10页
Background:This study aimed to evaluate the prognostic value of the lymphocyte-to-monocyte ratio(LMR)and cancer antigen 724(CA724)in patients with proximal gastric cancer residing in cold climate regions.Methods:A ret... Background:This study aimed to evaluate the prognostic value of the lymphocyte-to-monocyte ratio(LMR)and cancer antigen 724(CA724)in patients with proximal gastric cancer residing in cold climate regions.Methods:A retrospective analysis was conducted on 313 patients diagnosed with proximal gastric cancer in cold climate regions between 2014 and 2017.Preoperative hematological markers,including LMR and CA724,were assessed.Receiver operating characteristic(ROC)curves were used to determine optimal cutoff values,which were then combined to form the LMR+CA724 score.Statistical analyses included Kaplan-Meier survival curves,log-rank tests,and Cox proportional hazards regression.Results:A high preoperative LMR+CA724 score was significantly associated with older age,advanced pTNM stage,vascular invasion,and elevated levels of NMPVR,NMR,and AAR.The LMR+CA724 score demonstrated a higher area under the curve(AUC)compared to LMR or CA724 alone.Multivariate analysis identified pTNM stage,Borrmann type,histological type,and the LMR+CA724 score as independent prognostic factors for overall survival(OS).A nomogram incorporating these four variables achieved an AUC of 0.817,indicating strong predictive performance.Conclusion:The LMR+CA724 score is a reliable and independent prognostic indicator for patients with proximal gastric cancer in cold climate regions.Its integration into clinical practice may support treatment planning and long-term management by enhancing personalized care.Further prospective studies are warranted to validate these findings in broader and more diverse patient populations. 展开更多
关键词 proximal gastric cancer cold regions lymphocyte-to-monocyte ratio carbohydrate antigen 724 prognostic evaluation
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Influences of Seasonal Freezing and Thawing on Soil Water-stable Aggregates in Orchard in High Cold Region,Northeast China 认领 引用 被引量：6
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作者 LIANG Yunjiang DENG Xu +4 位作者 SONG Tao CHEN Guoshuang WANG Yuemei ZHANG Qing LU Xinrui 《Chinese Geographical Science》 SCIE CSCD 2021年第2期234-247,共14页
Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of ... Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of SFT on aggregate stability in orchards during winter and spring is crucial to develop appropriate management strategies that can effectively alleviate the degradation of soil quality to ensure sustainable development of orchard ecosystems.To determine the mechanism of degradation in orchard soil quality,the effects of SFT on the stability of water-stable aggregates were examined in apple-pear orchards(Pyrus ussuriensis var.ovoidea)of four different ages(11,25,40,and 63 yr)on 0 to 5%slopes before freezing and after thawing from October 2015 to June 2016 in Longjing City,Yanbian Prefecture,Northeast China,involving a comparison of planted versus adjacent uncultivated lands(control).Soil samples were collected to investigate water-stable aggregate stability in three incremental soil layers(0–20,20–40 and 40–60 cm).In the same samples,iron oxide,organic matter,and clay contents of the soil were also determined.Results showed that the destructive influences of SFT on water-stable aggregates were more pronounced with the increased orchards ages,and SFT exerted severe effects on water-stable aggregates of older orchards(40 and 63 yr)than juvenile orchards.Undergoing SFT,the soil instability index and the percentage of aggregate destruction increased by mean 0.15 mm and 1.86%,the degree of aggregation decreased by mean 1.32%,and the erosion resistance weakened,which consequently led to aggregate stability decreased.In addition,soil free,amorphous,and crystalline iron oxide as well as soil organic matter and clay contents are all important factors affecting the stability of water-stable aggregates,and their changes in their contents were consistent with those in the stability of water-stable aggregates.The results of this study suggest that long-term planting fruit trees can exacerbate the damaging effects of SFT on aggregate stability and further soil erosion increases and nutrient losses in an orchard,which hider sustainable use of soil and the productivity orchards. 展开更多
关键词 water-stable aggregates orchard age apple-pear orchard soil seasonal freezing and thawing soil degradation high cold region
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Structural analysis and design of frost resistance function for subgrade of high-speed railway ballasted track in cold regions 认领 引用 被引量：1
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作者 Qiang Luo WenQiang Lv +1 位作者 QingZhi Ye RuiGuo Zhang 《Research in Cold and Arid Regions》 CSCD 2015年第5期594-604,共11页
According to the technical characteristics of short fixed wheelbase of a high-speed carriage, a subgrade-track integrated space mechanical response analysis model is proposed for trains under the action ofbiaxial load... According to the technical characteristics of short fixed wheelbase of a high-speed carriage, a subgrade-track integrated space mechanical response analysis model is proposed for trains under the action ofbiaxial load after the comparison of the stress distribution characteristics of the ballast track subgrade bed structures for high-speed railway under the action of uniaxial load and biaxial load. The loading threshold value （high-cycle long-term dynamic strength） under the circum- stance where the cumulative deformation of subgrade structure gradually develops and finally reaches the convergent state, and its relationship with the foundation coefficient K30 were deduced, based on the characteristics of cumulative defor- mation evolution obtained from the unit structure filling model test under the action of cyclic loading. In view of structure stability and frost resistance requirements of the railway subgrade in cold regions, technical conditions to maintain good service performance of subgrade structure of high-speed railway ballasted track are discussed and analyzed. Study results show that the additive effect manifests itself obviously for railway train bogies under the action of biaxial load than uni- axial load, which has a significant dynamic effect on the subgrade bed bottom and a slight effect on the surface layer. Thus, the adoption of a biaxial load model in the design of a high-speed railway subgrade accurately reflects the vehicle load. Pursuant to the structure design principle, the design method of the subgrade structure of high-speed railway ballasted track is proposed to meet the technical requirements such as structural strength, bearing stiffness and high-cyclic and long-term stability. Technical indicators are obtained for the variation of thickness of the surface layer of reinforced sub- grade bed in the double-layer subgrade mode along with the change of K30 at the subgrade bed bottom. The double-layer structure mode of ＂closure on the upper layer and drainage on the lower layer＂ was proposed in order to meet the water- proofing and drainage requirements of the upper layer of the subgrade bed in cold regions. A dense-framework graded gravel filler with weak water permeability at a coefficient of 10 4 cm/s is used on the upper layer and the void-framework graded gravel filler at the water permeability coefficient of 10 2 cm/s is adopted on the lower layer. 展开更多
关键词 high-speed railway in cold regions subgrade structure biaxial load mode structural analysis design of frostresistance function
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Population Construction and Super-high Yield Characteristics of Japonica Super Rice in Cold Regions 认领 引用 被引量：1
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作者 陈书强 薛菁芳 +8 位作者 杨丽敏 赵海新 杜晓东 周通 王翠 张献国 单丽丽 李敏 潘国君 《Agricultural Science & Technology》 CAS 2016年第3期584-592,595,共9页
[Objective] This study was conducted to construct a super-high yield population of Japnica rice in cold regions of North China and to explore its characteristics. [Method] The super rice variety Longjing 21 was select... [Objective] This study was conducted to construct a super-high yield population of Japnica rice in cold regions of North China and to explore its characteristics. [Method] The super rice variety Longjing 21 was selected as the experimental material. Different row spacing（two levels）, plant spacing（three levels） and seedling number per hill（three levels） were designed in field trials. Then, the growth stages,dry matter accumulation, leaf area, yield and yield components of these different treatments were measured. [Result] Rice yield had significantly negative correlation with plant spacing and row spacing, but no significant correlation with seedling number per hill. Rice yield was mainly affected by plant spacing, and less affected by seedling number per hill. The best recommended specifications for plant spacing of super rice variety Longjing 21 were 24 cm for row spacing, 12 cm for plant spacing and five seedlings per hill, and the expected yield was 10 473.0 kg/hm^2.The increased number of total spikelets（4.5×108hm2or more） in populations was the major reason for high yield. Super-high yield populations had fewer tillers at the early growth stage and achieved the expected number of productive tillers at critical leaf-age（June 25）, and tiller number peaked at jointing stage（July 6） and was about 1.2 times of the expected number. The percentage of productive tillers in total tillers of super-high yield population was more than 85% at heading stage. At middle growth stage（from jointing to heading stage）, the dry matter accumulation, leaf area index（LAI） at heading stage, effective leaf area, spikelet number of population,spikelet number per leaf area unit（cm2）, and culm-sheath weight per stem of super-high yield population were significantly higher than those of other populations.At late growth stage（from heading to maturity stage）, the leaf area decreasing rate of super-high yield population was significantly smaller than that of other populations. At late growth stage（from heading to maturity stage）, the leaf area decreasing rate, crop growth rate, net assimilation rate, biomass accumulation, number of filled grains per leaf area unit（cm^2） and grain weight per leaf area unit（cm^2） of high-yield population were significantly higher than those of other populations. Output and translocation of dry matter（weight per stem and sheath and total filling rate at maturity） from heading to milky stage of super-high yield population were significantly higher than those of other populations. [Conclusion] The characteristics of superhigh yield rice in cold region of North China are enriching the amount of actual filling of sink through improving photosynthetic efficiency from heading to maturity stage on the basis of enough panicle numbers. 展开更多
关键词 Cold region Japonica super rice Population construction Super-high yield characteristics
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Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation 认领 引用
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作者 Ahmad F.Zueter Mohammad Zolfagharroshan +1 位作者 Navid Bahrani Agus P.Sasmito 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期643-654,共12页
Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental costs.In this study,a novel AGF technique is proposed deploying availabl... Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental costs.In this study,a novel AGF technique is proposed deploying available cold wind in cold regions.This is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling requirements.The introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration load.This design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the thermosyphon.Two Canadian mines are considered:the Cigar Lake Mine and the Giant Mine.The results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake Mine.Further,a cooling load of 2.4 GWh can be saved at the Cigar Lake Mine.Overall,this study provides mining practitioners with sustainable solutions of underground AGF. 展开更多
关键词 Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions
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Current developments of research on permafrost engineering and cold region environment:a report of the 8thInternational Symposium on Permafrost Engineering 认领 引用 被引量：1
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作者 FuJun Niu GuoYu Li +3 位作者 ShuPing Zhao ShuJuan Zhang YongGuo Zhao HuiJun Jin 《Research in Cold and Arid Regions》 2010年第2期93-103,共11页
The Eighth International Symposium on Permafrost Engineering was held in Xi’an,China,October 2009.The major topics discussed in the symposium included:permafrost engineering(involving design,construction and evaluati... The Eighth International Symposium on Permafrost Engineering was held in Xi’an,China,October 2009.The major topics discussed in the symposium included:permafrost engineering(involving design,construction and evaluation);mitigation of frost hazards in the regions affected by seasonally frozen ground;properties of frozen soils,model development and their applications;frost hazards and periglacial environments in mountain and plateau regions;climatic,environmental and cryospheric changes;and permafrost hydrology,cold regions water resources and land uses.The papers submitted to the symposium and lectures during the meeting represented some new developments of research on cold region engineering and environment.Here we summarized the works of the symposium in topics including:Permafrost engineering;General geocryology;Properties of frozen soils:model development and their applications;And climatic,environmental and cryospheric changes.During the symposium,the attendees pointed out that future studies should pay more attention to theoretical study and engineering mechanism study,and also on interaction between climate change and cold region environments and their engineering affects. 展开更多
关键词 the 8th symposium permafrost engineering cold region environment summarizing
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Discussion on pile axial load test methods and their applicability in cold regions 认领 引用
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作者 JiaWei Gao Ji Chen +2 位作者 Xin Hou QiHang Mei YongHeng Liu 《Research in Cold and Arid Regions》 CSCD 2022年第4期239-249,共11页
The measurement of pile axial load is of great significance to determining pile foundation design parameters such as skin friction and end bearing capacity and analyzing load transfer mechanisms.Affected by the temper... The measurement of pile axial load is of great significance to determining pile foundation design parameters such as skin friction and end bearing capacity and analyzing load transfer mechanisms.Affected by the temperature and ice content of frozen ground,the interface contact relationship between pile foundation and frozen soil is complicated,making pile axial load measurements more uncertain than that in non-frozen ground.Therefore,it is necessary to gain an in-depth understanding of the current pile axial load test methods.Four methods are systematically reviewed:vibrating wire sensors,strain gauges,sliding micrometers,and optical fiber strain sensors.At the same time,the applicability of the four test methods in frozen soil regions is discussed in detail.The first two methods are mature and commonly used.The sliding micrometer is only suitable for short-term measurement.While the Fiber Bragg grating(FBG)strain gauge meets the monitoring requirements,the Brillouin optical time-domain reflectometer(BOTDR)needs further verification.This paper aims to provide a technical reference for selecting and applying different methods in the pile axial load test for the stability study and bearing capacity assessment of pile foundations in cold regions. 展开更多
关键词 Pile axial load Test methods Pile shaft resistance Sensors Cold regions
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Numerical simulation of dynamic response of subgrade under moving heavy truck in cold regions 认领 引用
15
作者 Feng Zhang DeCheng Feng +1 位作者 XianZhang Ling QiongLin Li 《Research in Cold and Arid Regions》 CSCD 2013年第4期468-477,共10页
This paper reports on the dynamic response of highway subgmde under moving heavy Wuck in cold regions. Numerical simulations are performed in two stages. In the first stage, the moving heavy truck vibration, induced b... This paper reports on the dynamic response of highway subgmde under moving heavy Wuck in cold regions. Numerical simulations are performed in two stages. In the first stage, the moving heavy truck vibration, induced by mad roughness, is calculated through a three-dimensional dynamic interaction model of heavy tmckavement-subgrade, and the lime-histories of nodal loads on the top of the base are calculated through this model. In the second stage, a two-dimensional dynamic finite element model of the bgrade-ground system is formulated, using the calculated nodal loads from the first stage as input. The dynamic resporkse of the subgrade is validated by field measurements, and the effects of mack type, axle loading, running speed, and road roughness on the vertical dynamic slress in the unfrozen period and the spring thawing period are analyzed and discussed. 展开更多
关键词 lynamic response subgrade heavy truck numerical simulation cold regions
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Model test study of frost heaving pressures in tunnels excavated in fractured rock mass in cold regions 认领 引用 被引量：2
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作者 Bing Sun 《Research in Cold and Arid Regions》 2010年第5期405-410,共6页
Based on the similarity theory, taking the horseshoe, city-gate and round linings as examples, the value and distribution regularities of normal frost heaving pressures （hereinafter as frost heaving pressures） in tu... Based on the similarity theory, taking the horseshoe, city-gate and round linings as examples, the value and distribution regularities of normal frost heaving pressures （hereinafter as frost heaving pressures） in tunnels excavated in fractured rock mass in cold regions under different constraints and freezing depths were studied by a test model. It was found that the larger the frozen depth, the larger the frost heaving pressure, and the stronger the top constraint, the larger the frost heaving pressure. For the horseshoe lining and city-gate lining, the top constraint has a greater effect on the frost heaving pressures on the arch and the inverted arch. For the round lining, the influences of the top constraint on the frost heaving pressure in all linings are almost the same. The frost heaving pressure is maximum on the city-gate lining and minimal on the round lining. The largest frost heaving pressure all occur near the foot of the inverted arch for the three kinds of lining. Thus, the test data basically coincide with the observed in situ data. 展开更多
关键词 tunnel in cold region fractured rock mass frost heaving pressure model test
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Research on the Limit Value of Shape Coefficient of Rural Residences in Severe Cold Regions 认领 引用
17
作者 Hong Jin Kai Chen Teng Shao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期43-46,共4页
Shape coefficient is a significant factor accounting for building energy consumption. In order to decrease the building energy consumption of rural residence in severe cold regions,this paper from the perspective of r... Shape coefficient is a significant factor accounting for building energy consumption. In order to decrease the building energy consumption of rural residence in severe cold regions,this paper from the perspective of regulating the shape coefficient limit value,applies the field survey method to statistic and analyze the shape,width and depth of rural residence in severe cold regions and concludes the distribution characteristics and scope of building area. On this basis,though calculating and analyzing the relations between shape coefficient and length-width ratio under different building areas,meanwhile comprehensive considering the building function,farmers' living mode and requirements etc,it put forward that the shape coefficient of rural residence in severe cold regions should below 0. 8. It has important significance for guiding the rural energy-saving house design and construction of severe cold regions. 展开更多
关键词 severe cold regions rural residences shape coefficient
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Fracture criterion of tunnel surrounding rock with pores in cold regions 认领 引用
18
作者 SHU Jiajun DENG Zhengding WU Bingni 《水利水电技术（中英文）》 北大核心 2022年第3期176-184,共9页
In order to study the failure criterion of porous surrounding rock of tunnel in cold regions under the action of low temperature frost heave,the frost heave force and stress intensity factor of surrounding rock are so... In order to study the failure criterion of porous surrounding rock of tunnel in cold regions under the action of low temperature frost heave,the frost heave force and stress intensity factor of surrounding rock are solved based on frozen rock mechanics,fracture mechanics and meso-damage mechanics.The stress corrosion limit of rock instead of fracture toughness is taken as the crack initiation criterion.Under the action of single frost heave,the frost heave failure criterion of surrounding rock is established for the“main-side branch”pore structure which is prone to frost heave failure;Under the action of continuous frost heave,it is regarded as freeze-thaw cycle,the effect of rock debris loss during the cycle is considered,and the frost heave failure criterion of surrounding rock is established.Relying on the verification of the reliability of the instability criterion of a tunnel in a cold region of Tibet,it is found that the stress intensity factor of surrounding rock calculated by traditional fracture mechanics may be quite different from the real value.The above engineering examples are used to analyze the effect of different parameters on the stress intensity factor of surrounding rock.The results show that the stress intensity factor of surrounding rock is proportional to the axis diameter of main hole and water pressure.The growth rate of the stress intensity factor of the former in the initial stage is significantly higher than that in the late stage,while the latter increases almost linearly;It is inversely proportional to the ambient temperature and toughness ratio of surrounding rock,and the effect of temperature on surrounding rock instability is more obvious.The research results can improve the understanding of the frost heave failure characteristics of surrounding rock and improve the theoretical basis for the long-term stability of tunnel engineering in cold regions. 展开更多
关键词 frost-heave fracture damage capillary freezing meso damage mechanics main-side branch pore structure stress corrosion limit of rock groundwater porous surrounding rock of tunnel in cold region influence factor
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Incident analyses of frost heaving failure of municipal underground gas pipelines in cold regions of northern China 认领 引用
19
作者 YaMin Li HongSheng Li +1 位作者 ZengLi Liu LiShun Chen 《Research in Cold and Arid Regions》 2011年第6期473-477,共5页
In the cold regions of northern China, incidents of municipal underground gas pipeline rupture and leakage occur quite fi-equently, aaost often in winter. To prevent harm to citizen safety and property, analysis of th... In the cold regions of northern China, incidents of municipal underground gas pipeline rupture and leakage occur quite fi-equently, aaost often in winter. To prevent harm to citizen safety and property, analysis of the causes of such cracking and leakage is therefore valuable. Two incident analyses are discussed here and the reasons why most of these types of cases occur dttring winter are clarified. Fhe effects of vehicle loadings above buried pipelines are calculated and compared with the effects and calculations of frost heaving forces. We demonstrate thtit when the soil layer above a pipeline freezes rapidly, the soil generates repeated frost heaving, which exerts heaving forces on the pipeline that can result in fatigue crack propagation and ultimate pipeline failure. Therefore, the incident induced 9y frost heaving is one of the primary reasons of gas pipeline failure. Based on these analyses, we present some recommendations pertaining to the proper design, construction, and management of gas pipelines. 展开更多
关键词 cold regions underground gas pipeline frost heaving faihtre incident analysis
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Evolvement regularity of signal control parameters of urban road in cold region 认领 引用
20
作者 蒋贤才 苏小红 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期873-878,共6页
In snow-icy road environment, the survey data indicate that the largest decrease in traffic flow running characters occurs when snow and ice begin to accumulate on the road surface. Saturation flow is decreased by 16%... In snow-icy road environment, the survey data indicate that the largest decrease in traffic flow running characters occurs when snow and ice begin to accumulate on the road surface. Saturation flow is decreased by 16% , speed is decreased by 30% , and start-up lost time is increased by 27%. Based on the signal control theory of HCM and Webster, the character values of traffic flow in different urban road environments were investigated, and the evolvement regularity of signal control parameters such as cycle, split, green time, offset, yellow time and red time in snow-icy road environment was analyzed. The impact factors and the changes in the scope of signal control parameters were achieved. Simulation results and practical application show that the signal control plan of road enviromnent without snow and ice will increase the vehicle delay, stop length and traffic congestion in snow-icy road environment. Thus, the traffic signal control system should address a suitable signal control plan based on different road environments. 展开更多
关键词 evolvement regularity of signal control parameter traffic simulation cold region urban road
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