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| 1 | Ground-temperature controlling effects of duct-ventilated railway embankment in permafrost regions显示文摘Based on observed data from field-testing embankment of the Qinghai-Tibet Railway, ground-temperature controlling effect of duct-ventilated embankment is studied in this paper.The results show that ventilation ducts can effectively cool the soils surrounding the ducts of the embankment, and the heat budget of the ambient soils in a year shows as heat release. Temperature status of the permafrost below the embankment with ducts buried in the relatively high position is similar to that of the common embankment. The permafrost processes warming all along in the two freezing-thawing cycles when the embankment was constructed. However, the temperature of the frozen soils below the embankment, in which the ducts buried in the relatively low position, rises a little in the initial stage. After that, it cools down gradually. At the same time,ventilation ducts can effectively reduce the thermal disturbance caused by the filled soils. The frozen soils below the common embankment and that with high-posited ducts absorb heat all along in the initial two cycles. While the soils below the embankment with low-posited ducts begin to release heat in the second cycle. This phenomenon proves that the ventilation embankment with low-posited ducts shows efficient temperature-controlling effect. Such embankment can actively cool the subgrade soils and therefore keeps the roadbed thermally stable. | NIU Fujun CHENG Guodong YU Qihao | 2004 | Science China Earth Sciences2004，47，z1： | 16 |
| 2 | The application of auto-temperature-controlled ventilation embankment in Qinghai-Tibet Railway显示文摘Auto-temperature-controlled ventilation embankment is an effective engineering measure for 'cooling roadbed'. Practice proves that this new method can sufficiently make use of natural cold energy. It has the advantages of higher efficiency, better cooling effect and feasibility in engineering practice, and wider application in various environment, etc. And also, it is comparatively cheap in project cost. Through practice in the field for half a year, the testing results show that, with the application of auto-temperature-controlled system, the artificial permafrost table has been raised by 65 cm. The artificial permafrost table was basically at the embankment bottom, and the action of freeze-thaw circle on engineering stability was effectively avoided. In the month with highest ground temperature, in the scope with 1-4 m in depth, including the majority of the embankment and the upper part in the original seasonal layer, the ground temperature decreased by 0.7℃. Through thermal flux calculation in the original seasonal layer, in the month with the maximum thermal flux coming into permafrost, it is found that the thermal flux reduces nearly by half. Coming into the cooling period for nearly a month, the ground temperature in entire auto-temperature-controlled embankment is close to zero, and the foundation is at negative temperature. But in a large region in the embankment and foundation the ground temperature was over 0℃ and varied from 0℃ to 0.39℃ in ordinary ventilation embankment. | YU Qihao CHENG Guodong NIU Fujun | 2004 | Science China Earth Sciences2004，47，z1： | 14 |
| 3 | Comprehensive Management of Daily Living Activities,behavioral and Psychological Symptoms,and Cognitive Function in Patients with Alzheimer's Disease:A Chinese Consensus on Alzheimer's Disease显示文摘Alzheimer's disease(AD)is the most common cognitive disorder in the elderly.Its main clinical manifestations are cognitive decline(C),behavioral and psychological symptoms(B),and a decline in the activities of daily living(A),also known as ABC symptoms.Early identification and evaluation of ABC symptoms are helpful for establishing the accurate diagnosis,comprehensive treatment,and prognosis of AD.To guide Chinese clinical practice for optimization of the comprehensive management of AD,in 2018,The Academy of Cognitive Disorder of China gathered 22 neurologists and gerontologists in China to build a consensus on the comprehensive management of AD.Based on a review of the evidence,the consensus summarizes the pathogenesis,pathological changes,clinical manifestations,evaluation,diagnosis,drug and non-drug treatment,and patient care for AD.Focus group discussion was used to establish a flowchart of comprehensive ABC management for AD patients.The new consensus provides a feasible AD management process for clinicians. | Jianjun Jia Jun Xu Jun Liu Yongjun Wang Yanjiang Wang Yunpeng Cao Qihao Guo Qiuming Qu Cuibai Wei Wenshi Wei Junjian Zhang Enyan Yu | 2021 | Neuroscience Bulletin2021，37，7： | 10 |
| 4 | Refreezing of cast-in-place piles under various engineering conditions显示文摘In the construction of the Qinghai-Tibet Power Transmission Line(QTPTL), cast-in-place piles(CIPPs) are widely applied in areas with unfavorable geological conditions. The thermal regime around piles in permafrost regions greatly affects the stability of the towers as well as the operation of the QTPTL. The casting of piles will markedly affect the thermal regime of the surrounding permafrost because of the casting temperature and the hydration heat of cement. Based on the typical geological and engineering conditions along the QTPTL, thermal disturbance of a CIPP to surrounding permafrost under different casting seasons, pile depths, and casting temperatures were simulated. The results show that the casting season(summer versus winter) can influence the refreezing process of CIPPs, within the first 6 m of pile depth. Sixty days after being cast, CIPPs greater than 6 m in depth can be frozen regardless of which season they were cast, and the foundation could be refrozen after a cold season. Comparing the refreezing characteristics of CIPPs cast in different seasons also showed that, without considering the ground surface conditions, warm seasons are more suitable for casting piles. With the increase of pile depth, the thermal effect of a CIPP on the surrounding soil mainly expands vertically, while the lateral heat disturbance changes little. Deeper, longer CIPPs have better stability. The casting temperature clearly affects the thermal disturbance, and the radius of the melting circle increases with rising casting temperature. The optimal casting temperature is between 2 °C and 9 °C. | Lei Guo QiHao Yu XiaoNing Li XinBin Wang YongYu Yue | 2015 | Research in Cold and Arid Regions2015，7，4： | 8 |
| 5 | Heat transfer process of roadway embankments with different type and width of road surface in permafrost regions显示文摘自从它被热条件管理,在永久冻土区域的路基的稳定性在当前的气候变化下面在这些区域与高速公路,高速公路和铁路的快速的开发和建设成为了一颗大担心,或换句话说,在堤的热转移过程。我们执行了有限元素分析在堤热转移过程上分析道路表面的不同类型的效果和堤的宽度的效果。结果显示在有沥青表面的车道堤的底部的吝啬的年度热转移率与沙的石子表面是乘那的 3。当沥青表面的宽度被加倍时,这意味着转移率增加了 60% 的年度热。增加的热转移率主要在堤的底部被定位并且导致了热集中的效果,导致到差不多 1.6 次的永久冻土的降级。增加的堤高度不减少热转移率的这些增加,这也被发现。因此,两沥青道路表面和增加的堤宽度能在车道堤导致加强的热转移率,因而 degradating 内在的永久冻土和堤不稳定性。 | YU Qihao PAN Xicai CHENG Guodong BAI Yang | 2007 | Progress in Natural Science:Materials International2007，17，3： | 7 |
| 6 | Numerical analysis of applying special pavements to solve the frost heave diseases of high-speed railway roadbeds in seasonally frozen ground regions显示文摘The Haerbin-Dalian Passenger Dedicated Line is the first high-speed railway constructed in the seasonally frozen ground regions of northeastern China. Frost heave diseases occurred in the first winter of its operation(between October 2012 and January 2013), and frost heave was observed mainly in the roadbed fills that were considered not susceptible to frost heave. This paper proposes applying two special pavements — black pavement and insulation-black pavement — to improve the thermal regime of the roadbed. Three numerical models of the roadbed temperature field were built based on the field conditions of the Changchun section(D3K692+840 to D3K692+860). The results show that:(1) Compared with cement pavement, black pavement and insulation-black pavement could reduce the freezing index at the roadbed surface by 37% and 64%, respectively, which could influence the maximum frozen depth;(2) the maximum frozen depths under the black pavement and insulation-black pavement were respectively 1.3–1.4 m and 1 m. Compared with cement pavement, they could reduce the maximum frozen depth by 0.4 m and 0.7–0.8 m, respectively, which would reduce the permitted amount of frost heave by 4 mm and 7–8 mm, which would meet the deformation limit established by the Code for Design on Special Subgrade of Railway;(3) the freezing periods of the black pavement and the insulation-black pavement were, respectively, approximately four months and two months. Compared with cement pavement, they could reduce the freezing period by approximately 19 days and 40 days, respectively, and delay the initial freezing time by 9 days and 18 days; and(4) compared with cement pavement, black pavement and black-insulation pavement could reduce the frozen areas of roadbeds in the cold season, which suggests that these two special pavements could provide better thermal stability for roadbeds. | Chang Yuan FuJun Niu QiHao Yu XinBin Wang Lei Guo YanHui You | 2015 | Research in Cold and Arid Regions2015，7，4： | 5 |
| 7 | Neuropsychological features in post-stroke cognitive impairment with no dementia patients with different Traditional Chinese Medicine syndromes显示文摘OBJECTIVE: To investigate neuropsychological features of post-stroke cognitive impairment with no dementia(PSCIND) patients with different Traditional Chinese Medicine(TCM) syndromes.METHODS: We recruited 50 patients with PSCIND between April 2012 and March 2013. Patients were divided into different groups according to TCM classifications. Patients were assessed using neuropsychological tests, including cognitive screening(mini-mental state examination), memory testing (auditory verbal learning test), executive/attention[shape trails test, stroop color-word test(SCWT),reading the mind in the eyes test, the digit ordering test-A(DOT-A), and symbol digit modalities test], language(action naming test, Boston naming test, famous face test, similarity test, and verbal fluency test), and visuospatial functioning [complex figure test(CFT)].RESULTS: We found no significant differences between patients with and without a diagnosis of turbid phlegm blocking the upper orifices on neuropsychological test performance. Patients diagnosed with upper hyperactivity of liver Yang syndrome scored significantly lower on the SCWT-C executive test and the CFT-delayed recall memory test. Patients with excess syndrome scored significantly lower on the SCWT-C executive test, and significantly higher on the DOT-A executive test.CONCLUSION: Neuropsychological characteristics differ between PSCIND patients with different TCM classifications. | Ma Jie Wang Yu Zhang Yunyun Guo Qihao Zhen Xiaomin Shi Moyi | 2019 | Journal of Traditional Chinese Medicine2019，39，1： | 4 |
| 8 | Problems and countermeasures in construction of transmission line projects in permafrost regions显示文摘Construction of power transmission lines is becoming an important part of permafrost engineering in China.This paper reviews the construction status and problems of transmission lines in different countries,as well as corresponding solutions that would be of practical significance for sustainable engineering practices.Russia has the longest history of transmission line construction in permafrost areas,with transmission lines(mainly 220 kV and 500 kV) spanning approximately 100,000 km.However,all countries suffer from permafrost-related tower foundation stability problems caused by freezing-thawing hazards such as frost heave and thaw settlement,frost lifting,and harmful cryogenic phenomena.As point-line transmission line constructions,the lines,poles and towers should be reasonably selected and installed with a comprehensive consideration of frozen soil characteristics to effectively reduce the occurrence of freezing-thawing disasters.Reinforced concrete pile foundations are widely used in the permafrost regions,and construction in winter is also a universal practice.Moreover,facilitating engineering measures like thermosyphons are an effective way to reduce freezing-thawing hazards and to maintain the stability of tower foundations. | GuoShang Wang QiHao Yu YanHui You Ze Zhang Lei Guo ShiJun Wang Yong Yu | 2014 | Research in Cold and Arid Regions2014，6，5： | 2 |
| 9 | The changing process and trend of ground temperature around tower foundations of Qinghai-Tibet Power Transmission line显示文摘After the construction of Qinghai-Tibet Highway and Railway, the Qinghai-Tibet Power Transmission(QTPT) line is another major permafrost engineering project with new types of engineering structures. The changing process and trend of ground temperature around tower foundations are crucial for the stability of QTPT. We analyzed the change characteristics and tendencies of the ground temperature based on field monitoring data from 2010 to 2014. The results reveal that soil around the tower foundations froze and connected with the artificial permafrost induced during the construction of footings after the first freezing period, and the soil below the original permafrost table kept freezing in subsequent thawing periods. The ground temperature lowered to that of natural fields, fast or slowly for tower foundations with thermosyphons,while for tower foundations without thermosyphons, the increase in ground temperature resulted in higher temperature than that of natural fields. Also, the permafrost temperature and ice content are significant factors that influence the ground temperature around tower foundations. Specifically, the ground temperature around tower foundations in warm and ice-rich permafrost regions decreased slowly, while that in cold and ice poor permafrost regions cooled faster. Moreover, foundations types impacted the ground temperature, which consisted of different technical processes during construction and variant of tower footing structures. The revealed changing process and trend of the ground temperature is beneficial for evaluating the thermal regime evolution around tower foundations in the context of climate change. | YanLi Xie QiHao Yu YanHui You ZhongQiu Zhang TingTao Gou | 2019 | Research in Cold and Arid Regions2019，11，1： | 2 |
| 10 | Comparing the applications of EMD and EEMD on time-frequency analysis of seismic signal 显示文摘 | Wang Tong Zhang Mingcai Yu Qihao Zhang Huyuan | 2012 | Journal of Applied Geophysics2012，83，： | 1 |
| 11 | Impacts of permafrost mean annual ground temperature and ice content on thermal re- gime of pile foundation of Qinghai-Tibet Power Transmission Line显示文摘 | Li Guoyu Yu Qihao Ma Wei | 2013 | Advanced Materials Research2013，6106，： | 1 |
| 12 | Comparative analysisof the natural convection process between hollow concretebrick layer and crushed rock layer显示文摘 | Qian Jin Yu Qihao Jiang Ziqiang | 2012 | Cold Regions Scienceand Technology2012，70，： | 1 |
| 13 | An experimental study on the cooling mechanism of a shading board in permafrost engineering显示文摘 | Qihao Yu Xicai Pan Guodong Cheng Naiwu He | 2007 | Cold Regions Science and Technology2007，，3： | 1 |
| 14 | Degradation of permafrost in the Xing'anling Mountains, Northeastern China 显示文摘 | Jin Huijun Yu Qihao Lu Lanzhi | 2007 | Permafrost and Periglanial Processes2007，18，： | 1 |
| 15 | Linear and nonlinear vibration system identification 显示文摘 | Yu Qihao | 1994 | Shock and Vibration1994，，2： | 1 |
| 16 | Changes in per- mafrost environments along the Qinghai-Tibet engineering corri- dor induced by anthropogenic activities and climate warming显示文摘 | Jin Huijun Yu Qihao Wang Shaoling | 2008 | Cold Regions Science and Technology2008，53，3： | 1 |
| 17 | Comparative analysis of the natural convection process between hollow concrete brick layer and crushed rock layer显示文摘 | QIAN Jin YU Qihao JIANG Ziqiang | 2012 | Cold Regions Science and Technology2012，70，1： | 1 |
| 18 | Comparing the applications of EMD and EEMD on time-frequency a- nalysis of seismic signal 显示文摘 | Tong Wang Mingcai Zhang Qihao Yu | 2012 | Journal of Applied Geophys- ics2012，83，： | 1 |
| 19 | Qinghai-Tibet Expressway experimental research显示文摘As one part of the National Highway Network Planning in China, the Qinghai-Tibet Expressway (QTE) from Golmud to Lhasa will be built in the interior of the Qinghai-Tibet Plateau (QTP) across about 630 km of permafrost lands. Due to the problematic interactions between the engineering foundations and permafrost, the frozen-soil roadbed of the QTE will be subjected to the more intense thermal disturbances due to the wider black surface. The design and construction for long-term thermal and mechanical stability will face more severe challenges than those in ordinary highways and railways in the same region. In order to provide scientific support for cold regions engineering practices, the QTE Experimental Demonstration Project (EDP) was constructed in situ in the vicinity of the Beilu'he Permafrost Station in the interior of the QTP. In this paper, the anticipated problems of the proposed QTE project are enumerated, and the structures of the test sections for QTE EDP are described. Through numerical simulations, it was found that the heat transfer processes occurring in each specific road structure are significantly different. The heat accumulation in the highway embankment is mainly due to the black bituminous pavement, but in the railway embankment with its gravel surfaces, it mainly comes from the side slopes. As a result, the net heat accumulation of the highway embankment is three times higher than that in the railway. In expressway, the heat accumulation is further increased because of the wider pavement so that significantly more heat will be accumulated in the roadbed beneath the centerline area. Thus, the thermal stability of the fro- zen-soil roadbed and the underlying permafrost of the QTE can be seriously threatened without proper engineering measures protection against thawing. Based on research and practical experiences from the operating Qinghai-Tibet Railway (QTR) and the Qinghai-Tibet Highway (QTH), combined with the predicted characteristics of heat transfer in an expressway embankment, nine kinds of engineering measures for mitigating the thaw settlement of foundation soils through the cooling the roadbed soils were built and are being tested in the EDP. The design of the monitoring system for the EDP and the observed parameters were also described. | Wei Gu QiHao Yu Jin Qian HuiJun Jin JianMing Zhang | 2010 | Research in Cold and Arid Regions2010，2，5： | 1 |
| 20 | Continuous and simultaneous measurement of reflector depth and average soil-water content with muhichannel gronnd-penetraing radar 显示文摘 | Gerhards H Wollschalger U Yu Qihao | 2008 | Geophysics2008，73，4： | 1 |
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