A machine learning approach for the prediction of pore pressure using well log data of Hikurangi Tuaheni Zone of IODP Expedition 372,New Zealand

Pore pressure(PP)information plays an important role in analysing the geomechanical properties of the reservoir and hydrocarbon field development.PP prediction is an essential requirement to ensure safe drilling operations and it is a fundamental input for well design,and mud weight estimation for wellbore stability.However,the pore pressure trend prediction in complex geological provinces is challenging particularly at oceanic slope setting,where sedimentation rate is relatively high and PP can be driven by various complex geo-processes.To overcome these difficulties,an advanced machine learning(ML)tool is implemented in combination with empirical methods.The empirical method for PP prediction is comprised of data pre-processing and model establishment stage.Eaton's method and Porosity method have been used for PP calculation of the well U1517A located at Tuaheni Landslide Complex of Hikurangi Subduction zone of IODP expedition 372.Gamma-ray,sonic travel time,bulk density and sonic derived porosity are extracted from well log data for the theoretical framework construction.The normal compaction trend(NCT)curve analysis is used to check the optimum fitting of the low permeable zone data.The statistical analysis is done using the histogram analysis and Pearson correlation coefficient matrix with PP data series to identify potential input combinations for ML-based predictive model development.The dataset is prepared and divided into two parts:Training and Testing.The PP data and well log of borehole U1517A is pre-processed to scale in between[-1,+1]to fit into the input range of the non-linear activation/transfer function of the decision tree regression model.The Decision Tree Regression(DTR)algorithm is built and compared to the model performance to predict the PP and identify the overpressure zone in Hikurangi Tuaheni Zone of IODP Expedition 372.

使用Flotherm和Expedition协同完成电子设备芯片级热仿真

随着电子设备不断地集成化、综合化,只靠单一热仿真软件(如Flotherm)一次完成电子设备芯片级的热仿真越来越困难,以某侧壁风冷机载电子设备为例,通过Flotherm和Expedition协同完成芯片级热仿真,并与实测值进行比较来验证仿真的准确性,保障电子设备工作的可靠性。

Expedition的RF模块在ADS仿真中的应用

将ADS的Momentum仿真与Expedition的电路设计相结合,提供一种新的射频微波电路仿真的建模方法。

Overview of the 9th Chinese National Arctic Research Expedition

The 9th Chinese National Arctic Research Expedition was carried out from 20 July to 26 September 2018. The expedition was successful in undertaking multidisciplinary comprehensive surveys in the fields of physical oceanography, marine meteorology, sea ice, marine chemistry,marine biology, marine ecology, geology, and geophysics in the Bering Sea, Chukchi Sea, Chukchi Plateau, Mendeleev Ridge, and Canada Basin. This paper gives an overview of the main achievements of this expedition and highlights the scientific achievements.

Leveraging the UAV to support Chinese Antarctic expeditions:a new perspective

Recent developments in Unmanned Aerial Vehicles(UAVs)and their applications in various subjects are of interest to polar communities.Due to the harsh climate and dangerous environment,these regions pose challenges for the expedition teams.Several countries have tested the UAV technology to support Antarctic research and logistics.In this trend paper,we provide insightful reviews and discussions on such a prospective topic.Based on a comprehensive literature survey,we firstly summarize the key research progress of UAV in Antarctic studies.Then the examples of risk scenarios during the field exploration are given,after which several promising applications of the UAVs in safety guarantee are illustrated.In particular,we present a case of site-selection for the Chinese first ice sheet airfield,using the data collected in the 34th Chinese National Antarctic Research Expedition(CHINARE).In the end,we highlight the unique value of the UAVs in the popularization of polar science before concluding the advantages and limitations.Considering their excellent performance,we expect more innovations for UAV’s applications in the following Antarctic expeditions.

Measurements of physical characteristics of summer snow cover on sea ice during the Third Chinese Arctic Expedition

The spatial distribution of snow cover on the central Arctic sea ice is investigated here based on the observations made during the Third Chinese Arctic Expedition. Six types of snow were observed during the expedition： new/recent snow, melt-fi＇eeze crust, icy layer, depth hoar, coarse-grained, and chains of depth hoar. Across most measurement areas, the snow surface was covered by a melt-freeze crust 2-3 cm thick, which was produced by alternate strong solar radiation and the sharp temperature decrease over the summer Arctic Ocean. There was an intermittent layer of snow and ice at the base of the snow pack. The mean bulk density of the snow was 304.01~29.00 kg/m3 along the expedition line, and the surface values were generally smaller than those of the sub- surface, confirming the principle of snow densification. In addition, the thicknesses and water equivalents of the new/recent and total-layer snow showed a decreasing trend with latitude, suggesting that the amount of snow cover and its spatial variations were mainly determined by precipitation. Snow temperature also presented significant variations in the vertical profile, and ablation and evaporation were not the primary factors in the snow assessment in late summer. The mean temperature of the surface snow was -2.01±0.96℃, which was much higher than that observed in the interface of snow and sea ice.

Different physiopsychological changes between AMS-susceptible and AMS-resistant pre-selected Antarctic expeditioners in Tibet

Through dynamically monitoring changes of acute mountain sickness(AMS)occurrences,cardiopulmonary function and mood states from Shanghai(4 m)to Lhasa(3650 m)and Yambajan(4300 m),Tibet,we obtained physiopsychological data of the 37th Chinese Antarctic pre-selected expeditioners for Kunlun Station.Through analyzing different physiopsychological changes between AMS-susceptible(AMS-S)and AMS-resistant(AMS-R)expeditioners,we would explore indicators to screen hypoxia-susceptible expeditioners.According to AMS occurrences evaluated by Lake Louise Score(LLS)in Yambajan,we divided the expeditioners(n=24,31.92±5.76 a)into AMS-S and AMS-R groups.Using a series of medical instrumentsand questionnaires,we monitored their cardiopulmonary function and mood states,and analyzed the differences of physiopsychological parameters between AMS-S and AMS-R groups.Compared with Shanghai,when expeditioners arrived in Yambajan,in both AMS-S and AMS-R groups,oxygen saturation(SpO2)significantly decreased,and blood pressure significantly increased(P<0.05).As for electrocardiogram(ECG),interval from the beginning to the end of QRS complex wave(QRS),interval from the beginning of QRS complex wave to the end of T wave(QT),interval between 2 adjacent P waves(PP)and interval between 2 adjacent R waves(RR)significantly decreased,heart rate(HR)and HR-corrected QT interval(QTc)significantly increased(P<0.05).Cardiac contractility and pumping function significantly decreased,systemic vascular resistance significantly increased(P<0.05).Pulmonary airway patency significantly increased(P<0.05).Compared with AMS-R group,AMS-S group showed significantly lower SpO2 and higher stroke volume variation(SVV)in Shanghai,however,significantly lower maximal expiratory flow at 75%of forced vital capacity(MEF75),higher levels of anxiety,fatigue and confusion in Yambajan(P<0.05).In conclusion,when expeditioners arrived at 4300 m,their cardiopulmonary function and mood states changed significantly.SpO2,SVV,MEF75,anxiety,fatigue and confusion maybe could be used as clues for screening hypoxia-susceptible individuals.

Sleep architecture, periodic breathing and mood disturbance of expeditioners at Kunlun Station(4087 m) in Antarctica

Several studies have reported the detrimental impacts of hypoxia exposure on sleep.Chinese Kunlun Station(altitude 4087 m)is located at Dome A,the highest point on the Antarctic ice sheet and one of the most extreme environments on Earth.This study investigated alteration of sleep,breathing and mood status in healthy expeditioners at Kunlun Station at Dome A.The study examined 10 male volunteers of the inland transverse party to Kunlun Station during the 31st Chinese National Antarctic Research Expedition,and valid data from eight volunteers were analyzed.Sleep structure,breathing pattern and mood were monitored using portable polysomnography(PSG)and profile of mood state(POMS)at two time points:(1)at Zhongshan Station(10 m)before departure to Kunlun Station;(2)on nights 12–13 of residence at Kunlun Station.Slow-wave sleep(Stage 3 non-rapid eye movement)was markedly reduced at Kunlun Station(P<0.01).Total sleep time,sleep efficiency and sleep latency showed no significant changes.Total respiratory events(P<0.05),apnea/hypopnea index(AHI)(P<0.05)and hypopnea index(P<0.01)substantially increased at Kunlun Station.The most common respiratory disorder was periodic breathing,occurring almost exclusively during non-rapid eye movement sleep.The oxygen desaturation index increased markedly(P<0.05),while nocturnal oxygen saturation dramatically fell at Kunlun Station(P<0.05).Vigor scores decreased at Kunlun Station(P<0.05).Expeditioners exhibited reduced slow wave sleep,induced periodic breathing,decreased oxygen saturation and decreased vigor at Kunlun Station.

Expedition在高速公路费用管理中的应用

根据高速公路建设管理中对费用监控的要求， 论述了费用管理中计算机辅助管理的必要性； 通过应用合同控制程序—— Ｅｘｐｅｄｉｔｉｏｎ， 进行费用控制， 使工程投资管理达到程序化、规范化， 简捷化。

Changes of serum thyroid hormone and plasma catecholamine of 16 th and 17 th Chinese Expeditioners in Antarctic environment

The serum thyroid hormone and plasma catecholamine were examined in 18 male and 2 female members of the Chinese Antarctic Expedition (who spent the 2000 or 2001 austral winter at the Great Wall Station) . The changes of serum thyroid hormone i. e. total thyroxine (TT4) and free T4 (FT4) , total triodothyronine (TT3) and freeT3 ( FT3 ) , thyroid stimulating hormone ( TSH ) and plasma catecholamine, including norepinephrine (NE) , epinephrine ( E) and dopamine ( DA ) , were investigated by Chemoluminescence Immunoassay (CLIA) and High Performance Liquid Chromatography with electrochemical detection (HPLC-ECD) . Samples were taken at different time; (1)1 day before departure to Antarctica (16th expedition 1999/12/ 09; 17th expedition 2000/12/06). (2) 1 day after returned to China after living 54 weeks in Antarctica ( 16th expedition 2000/12/25 ; 17th expedition 2001/12/25 ). Comparing the data of before departure and returned, results showed that there was a significant decrease in the contents of TT4 (P <0. 01) with no significant change in the content of TT3 , FT3 and FT4. It was also found that the content of TSH increased significantly (P <0. 001) ; No significant changes of plasma NE and DA were found but the content of E decreased significantly ( P < 0. 001) . The results indicated that the special Antarctic environment led to a restrain effect on the thyroid function and the level of plasma E in Antarctic expedition members. Both the thyroid and adrenal medulla system were associated in response to the Antarctic systemic stress.

Studies on the plasma tryptophan and urinary 5-hydroxy-3-indoleacetic acid in expedition members residing in Antarctica

In order to clarify the possible relationship between the changes of behavior/personality and metabolic changes of 5 hydroxytryptamine (5 HT) in Antarctic expedition members, plasma tryptophan (Trp) and urinary 5 hydroxy 3 indoleacetic acid (5 HIAA) were studied for 24 winter over and 19 summer over members of the 8th and 11th CHINARE respectively. Results showed that plasma Trp decreased significantly after residing 1￣3 months at Great Wall Station and did not recover on returning back to Beijing from Antarctica by two weeks travelling. Urinary 5 HIAA increased significantly after residing 6 months at Great Wall Station, and recovered on returning back to Beijing from Antarctica in the winter over members. The decrease of plasma Trp may be related to the decline of brain 5 HT which might play a role in the changes of behavior/personality . Increase of urinary 5 HIAA might reflect metabolic changes of 5 HT as a whole, but cold weather involving in the release response of platelet should be considered. Therefore, supplement of related food rich in Trp or intervention of L Trp might be valuable.

Experimental Application of Intelligent Robot Technology in Antarctic Scientific Expedition

Intelligent robot technology has great potential for application in polar scientific expedition.During the 24th Chinese Antarctic Expedition in the summer of 2007/08,our ice-snow surface mobile and low-flying robots were successfully employed for the first time in the Antarctic.This paper firstly gives a brief introduction to the intelligent robot technology developed abroad and used in the Antarctic,then focuses on the ice-snow surface mobile and low-flying robots developed by China as well as their field trials in the Antarctic.Moreover,the authors have considered the potential demand for the intelligent robot technology in China＇s Antarctic scientific expedition,in the hope of providing some reference for the future development of robot technologies.

Latitudinal distribution of CO_2 and CH_4 on the route of the Chinese Arctic R esearch Expedition 2003

During the 2nd Chinese Arctic Research Expedition, 20 pair of atmospheric samples were collected on the cruising route from Shanghai to Arctic Ocean using NOAA/ESRL flask sampling unit. Mean concentration of CO2 and CH4 were analyzed in different latitude zone from 30°N to 80°N and the distribution characteristics were studied. Mean concentration of CO2 decrease toward high latitude which indicates the uptake effect of CO2 by ocean. Coinciding with the CH4 global distribution character, mean CH4 concentration increase from 45°N to the North Pole region. Regional or local air mass may influence the greenhouse gas concentrations near seashore in the middle latitude （30°N-45°N）.

A survey on changes of multiple humoral factors in Antarctic expedition members

Since Changes of cardiac function, el ectroencephalogram findings, immune responses as well as the personality of the Antarctic expedition members had been reported by our group, the underlying contribution of behavior and physiological changeS would be further studied in this time. Samples were taken,under standardized procedures, on the same individual at different time such as (A) before leaving to Antarctica(B) 2 weeks after arrival at Great Wall Saution(C) 12. 5 months after arrival(D) after returning back to Beijing for a break(summer-over memos) (E)after returning back to Dening for a long break(winter-over member).Results showed that a Prominent increase of urinary Noradrenaline(NE) in Antarctica(B) decreased at(C),and retUrned to the normal range in comparison with(A) and(D). The increase Of urinary Adrenaline was even greater than that of NE at Antarctica(B). It indicated that an rather early response in activation of sylnpothetic system,especially the adrenal glands,gradually lowered down as time went on.Plasma and urinary cortisol also inereased significantly at Antarctica(B), but sustained for a long time even after returning back to Beijing. Both parameters are closely related to stress syndrome.Plasma Tryptophan decreased significantly at Antarctica (B). Some even sustained after retUrning to Beijing(E). Whether or not,such changes might correlated to the change of 5-HT metabolism in brain,in turn to show some effeCt on psychoological or mental disturbanceS,which should be carefully evaluated.Serum MDA, the perokidation product, increaSing together with the findings of decreased RBC SOD activity, the scanvengrr for O2, and increased plasma glucuronidase, the lysozyme release from damage of lysosome membrane, strongly indicated the presence of cellular damage by increasing O2 production and membrase perokidation and with damage Of lysosome unduly. Severe cold and extensive ultraviolet expeure should be considered carefully.The sitwficances of the above findings were discuss and the possible preventive or therapeutic measures have ben suggested. Since the destruction of the ozonelayer might increase the extent of ultraviolet radiation,it is worth to further investigate the biological damage effect of ultraviolet in Antarctica.

Seismic stratigraphy and the sedimentation history in the Laxmi Basin of the eastern Arabian Sea:Constraints from IODP Expedition 355

Detailed interpretation of seismic stratigraphic sequences in the Laxmi Basin of the eastern Arabian Sea are presented in this study using closely spaced high resolution multi-channel seismic(MCS)data.Our stratigraphic interpretation is further corroborated using recent drilling results in the Laxmi Basin,derived from the long sediment cores collected during International Ocean Discovery Program(IODP)Expedition 355.Integrated core-log interpretation discussed in the present study,offer important insights about the lithostratigraphic variations in this region.Analyses of multi-channel seismic reflection data reveal five depositional sequences(ranging from Paleocene to Recent)that led to the development of this marginal basin since the Cenozoic period.Regional igneous basement is successfully imaged,which was also validated by deep sea coring during the IODP Expedition 355.In the present study,we primarily focus on the post-rift sedimentation in the Laxmi Basin and its possible mechanisms.Our detailed interpretation in the prevailing tectonic framework of the basin suggests that near-shelf oldest volcaniclastic sedimentation immediately overlying the acoustic basement is linked to the onset of India-Madagascar and India-Seychelles rifting activities during the Late Cretaceous period.Eventually,during the Early-Mid to Late Miocene,the basin received maximum sedimentation dominantly through an extensive mass transport mechanism implying possible large-scale deformation on the Indian shelf.Subsequent sediment input to the basin appears to have been fed variably via the Indus Fan as well as coastal discharge from the Indian mainland.The total sediment thickness in the Laxmi Basin ranges from 1.1 to 3.5 km.New stratigraphic information and sediment isopach maps presented here provide vital information about syn-and post-rift sedimentation pattern in the region and their long term tectonic implications.

Chemical composition of marine aerosols of the 26th Chinese National Antarctic Research Expedition

The ionic compositions of aerosol samples collected during the 26th Chinese National Antarctic Research Expedition were analyzed and the sources of ions were distinguished. Cl-, Na＋, SO2-, NO3-, and Mg2＋ were the most abundant ionic components in the marine aerosols. Cl- and Na＋ contributed over 70% in the total ionic composition, indicating the sea salt is still the primary composition in marine aerosols, followed by the sulfate as the secondary ionic component existed as NH4N03, NH4HSO4, （NH4）2S04. The maximal sea salt concentrations were found at around 40~S and could be attributed to greater winds. The concentrations of methane sulfonic acid （MSA） appeared increasing trend from the low to high latitudes, possibly caused by lower temperature in air and higher marine biological processes in the marginal waters in Antarctica. The correlation and factor analyzes were used to investigate possible sources of these ions. Cl-, Br-, Na＋, K＋, Mg2＋ and Ca2＋ had predominantly marine sources; while F-, NO3 and NH＋ had mostly anthropogenic sources; MSA had marine biogenic sources. The concentrations of SO42- were influenced by both marine and anthropogenic sources.

Caesar’s British Expedition:What Are the Real Intentions Behind His Two Expeditions?

This paper aims to discuss the real intention behind Caesar’s two British expeditions and the evidence against the conquest theory.In Commentarii de Bello Gallico,Caesar claimed that he invaded Britain because he would like to teach the Britons a lesson for aiding the Gauls.Most modern scholars disagree that Caesar’s true intention is what Caesar has said,so they come up with their own theories.Ranzani says Caesar’s expedition is for glory,while Deutsch argues that Caesar’s expeditions are for pearls.Mitchell suggests that Caesar went to Britain for tin,while Ranzani,Schadee,Raaflaub,and Riggsby all come up with the theory of Caesar’s military and political gains.Brady is one of the few scholars who believe in what Caesar has said-to punish the Gauls.Moreover,Brady also considers Caesar’s expeditions a success since he does not think Caesar’s true goal is to conquer Britain.

On scientif ic expedition tourism of desert region:a case of eastern Ulan Buh Inner Mongolia

Desert-based adventure tourism is a rapidly expanding tourism market segment after the late 20^th century around the world. Perhaps the most significant factor in the development of desert adventure tourism is the extent to which common tourists are really engaged in scientific expedition. Inner Mongolia has long been considered as the resources accumulation area of desert tourism. The investigation on the Ulan Bah Desert has discovered that the desert animals, the vegetation, the insects, the fungus, tire landfrom and the climate are impressive for both the researchers and the mass tourists. After the resources investigation a survey was carried out in 2007 to get the detailed information of the tourists＇ attitude toward the planning desert scientific product in the Ulan Buh Desert. Based on the resources and market analysis, this paper tries to make a planning of the desert scientific expedition tour of the Ulan Bah Desert. The planning includes the functional division, expedition route design, tour-explaining system, facility of safety guaranty and service planning, and the professional training base.

THE EASTERN EXPEDITION OF LUCIUS VERUS(AD 162-166)

“The travels of the Caesars bring in most aspects of imperial history”.Such wasthe assertion of Syme in his survey of the peripatetic reign of Hadrian(1988,159).After Hadrian,the next journey of real significance undertakn by anemperor was that of Lucius Verus,who spent five years away from Rome ascommander of military campaigns in the east.These travels,like those of Hadrian,