Development of a pressure coring system for the investigation of deep underground exploration

To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyses and numerical simulation.The designed pressure coring system can obtain cores with length of 3 m and diameter of 50 mm at 70 MPa.The results of the ball-drop operation experiment demonstrate that differential motion assembly can effectively cut a safety pin by applying a tensile force of 4852 N,and it can lift the core tube through the center pole to complete a series of mechanical actions to seal the pressure.Additionally,by maintaining pressures at 70 MPa for 30 min,the pressure sealing capacity of the system was proven.Furthermore,a core sample with a diameter of 50 mm was obtained through a core drilling experiment and the coring performance of the pressure coring system was verified.This study can not only enrich the existing onshore coring technology but also provide a theoretical guide and design criteria for the development of similar pressure coring systems to meet the demand for deeper underground exploration.

Contact performance analysis of pressure controller's sealing interface in deep in-situ pressure-preserved coring system

The sealing performance of contact interfaces plays the most important role in the design and operation of the in-situ pressure-preserved coring system.To meet the demand of ultra-high pressure-retained coring for oil and gas exploration in deep reservoirs,a quantitative analysis of the contact mechanical behavior of the pressure controller was performed.Based on the micro-contact theory of rough surfaces,a three-dimensional numerical model of the rough contact interface between the valve cover and the valve seat was constructed,and the micro-contact behavior of the metal contact surfaces was comprehensively studied.The results show that the actual contact area of the valve interface increases with the increase of surface roughness before the critical contact point,but decreases after that.Compared with the real contact model with double rough surfaces,although the simplified hard-contact model with a single rough surface can reflect the micro-contact behavior of the rough surface to a certain extent,it cannot truly reveal the microchannel morphology between the sealing interfaces under pressure.Therefore,the realistic double-rough-surface model should be recommended to evaluate the sealing performance of coring tools,particularly for high pressure conditions.The material properties of valves have a significant effect on the contact characteristics of rough surfaces,which suggested that the actual contact area decreases with the increase of the elastic modulus of the contact material under the same loading conditions.The knowledge of this work could help to enhance the seal design of pressure controllers for in-situ pressure-preserved coring.

Research on Partner Selection in Enterprise Innovation Ecosystem

In the face of fierce market competition,enterprises must ensure the competitiveness of their products or services through technological innovation.However,the complexity of technology often surpasses the capabilities of individual enterprises,leading them to deepen cooperation with other organizations.The entities within the enterprise innovation ecosystem depend on each other,collaborate closely,and rely on core enterprises to integrate resources,thereby creating system value and enhancing competitiveness.The purpose of this paper is to explore the process of selecting appropriate ecosystem partners.It begins by providing an overview of relevant concepts,characteristics,selection factors,and methods.Subsequently,it analyzes the roles,resources,and synergy evolution of the entities within the ecosystem.An evaluation system encompassing operation,core,synergy,and development capability is then established.This system comprises 16 indicators,including organization scale and reputation,and is accompanied by a hierarchical evaluation model.Finally,the validity of the evaluation system is confirmed through empirical analysis,utilizing the Analytic Hierarchy Process(AHP)and the fuzzy comprehensive evaluation method.

Research on in-situ condition preserved coring and testing systems

As shallow resources are increasingly depleted,the mechanics'theory and testing technology of deep insitu rock has become urgent.Traditional coring technologies obtain rock samples without retaining the in-situ environmental conditions,leading to distortion of the measured parameters.Herein,a coring and testing systems retaining in-situ geological conditions is presented:the coring system that obtains in-situ rock samples,and the transfer and testing system that stores and analyzes the rocks under a reconstructed environment.The ICP-Coring system mainly consists of the pressure controller,active insulated core reactor and insulation layer and sealing film.The ultimate bearing strength of 100 MPa for pressurepreservation,temperature control accuracy of 0.97%for temperature-retained are realized.CH_(4)and CO permeability of the optimized sealing film are as low as 3.85 and 0.33 ppm/min.The average tensile elongation of the film is 152.4%and the light transmittance is reduced to 0%.Additionally,the pressure and steady-state temperature accuracy for reconstructing the in-situ environment of transfer and storage system up to 1%and±0.2 is achieved.The error recorded of the noncontact sensor ring made of lowdensity polymer is less than 6%than that of the contact test.The system can provide technical support for the deep in-situ rock mechanics research,improving deep resource acquisition capabilities and further clarifying deep-earth processes.

In-situ pressure-preserved coring for deep exploration:Insight into the rotation behavior of the valve cover of a pressure controller

In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of the pressure controller valve cover in different medium environments is unclear,interference between the valve cover and inner pipe may occur and negatively affect the IPP-Coring success rate.To address this issue,we conducted a series of indoor experiments employing a high-speed camera to gain greater insights into the valve cover rotation behavior in different medium environments,e.g.,air,water,and simulated drilling fluids.The results indicated that the variation in the valve cover rotation angle in the air and fluid environments can be described by a one-phase exponential decay function with a constant time parameter and by biphasic dose response function,respectively.The rotation behavior in the fluid environments exhibited distinct elastic and gravitational acceleration zones.In the fluid environments,the density clearly impacted the valve cover closing time and rotation behavior,whereas the effect of viscosity was very slight.This can be attributed to the negligible influence of the fluid viscosity on the drag coefficient found in this study;meanwhile,the density can increase the buoyancy and the time period during which the valve cover experienced a high drag coefficient.Considering these results,control schemes for the valve cover rotation behavior during IPP-Coring were proposed for different layers and geological conditions in which the different drilling fluids should be used,e.g.,the use of a high-density valve cover in high-pore pressure layers.

Design and development of the deep-rock in-situ condition-preserved coring calibration platform

To systematically validate and calibrate the theory and technology of the deep in-situ conditionpreserved coring, the in-situ conditions at different depths should be simulated, and the full-size coring tests should be carried out in this simulated environment. Therefore, a deep-rock in-situ conditionpreserved coring calibration platform was designed and developed. The self-tightening sealing structure and the quick-disassembly structure were designed on the basis of an innovative segmented nonuniformdiameter structure, which was a breakthrough from the traditional high-pressure vessel frame and was verified by finite element simulation and actual testing under extreme working conditions, respectively.To simulate the actual deep in-situ environment with a temperature of 150℃ and pressure of 140 MPa for a large Φ450 mm×H1400 mm core, temperature and pressure control systems were designed by coupling, and a pre-embedded high-pressure-resistant temperature sensor was designed. Finally, highprecision assembly automation, complex movement coordination of the coring device with the platform,and rotary dynamic sealing were achieved by utilizing the combination of adaptive cabin body servo control and an adaptive mechanical structure in a limited space, laying a solid foundation for the calibration of in-situ condition-preserved coring.

Research progress and application of deep in-situ condition preserved coring and testing

With the depletion of shallow resources,the exploration of deep earth resources has become a global strategy.The study of the different patterns in the physical mechanical properties of rocks at different occurrence depths is the basis for exploring deep into the earth,with the core and premise being the acquisition and testing of deep in-situ core specimens.Based on the original idea of deep in-situ condition preserved coring(ICP-Coring)and testing,combined with theoretical modeling,numerical analysis,test platform development,indoor testing and engineering application,the principles and technologies of deep ICP-Coring are developed.This principle and technology consists of five parts:in-situ pressurepreserved coring(IPP-Coring),in-situ substance-preserved coring(ISP-Coring),in-situ temperaturepreserved coring(ITP-Coring),in-situ light-preserved coring(ILP-Coring),and in-situ moisturepreserved coring(IMP-Coring).The theory and technology of temperature and pressure reconstruction at different occurrence depths and in different environments are proposed,and prototype trial production was completed by following the principle of displacement and tests based on the in-situ reconstructed environment.The notable advances are as follows:(1)Deep in-situ coring system:A pressure-preserved controller with an ultimate bearing capacity greater than 140 MPa,highperformance(temperature-resistant,pressure-resistant,and low thermally conductive)temperaturepreserved materials,an active temperature control system,and high-barrier quality-preserved membrane materials were developed;a deep ICP-Coring capacity calibration platform was independently developed,a deep in-situ coring technology system was developed,and the acquisition of deep in-situ cores was realized.(2)In-situ storage displacement system:Following the dual-circuit hydraulic design idea,a single-drive source push-pull composite grabbing mechanism was designed;the design of the overall structure for the deep in-situ displacement storage system and ultrahigh pressure cabin structure was completed,which could realize docking the coring device and core displacement in the in-situ reconstructed environment.(3)Test analysis system:A noncontact acoustic-electric-magnetic test system was developed under the in-situ reconstructed environment,and the errors between the test results and traditional contact test results were mostly less than 10%;a detachable deep in-situ core true triaxial test system was developed,which could perform loading tests for deep in-situ cores.The relevant technological achievements were successfully applied to the exploration and development of deep resources,such as deep mines,deep-sea natural gas hydrates,and deep oil and gas.The research results provide technical and equipment support for the construction of a theoretical system for deep in-situ rock mechanics,the development of deep earth resources and energy,and the scientific exploration of different layers and occurrence depths(deep and ultradeep)of the Earth.

Study of a low-disturbance pressure-preserving corer and its coring performance in deep coal mining conditions

With the increasing depth of coal mining,the requirements for coring devices that maintain pressure are increasing.To adapt to the special environment in deep coal seams and improve the accuracy of testing gas content,a low-disturbance pressure-preserving corer was developed.The measurement of gas content using this corer was analyzed.The coring test platform was used to complete a coring function test.A pressurized core with a diameter of 50 mm was obtained.The pressure was 0.15 MPa,which was equal to the pressure of the liquid column of the cored layer,indicating that the corer can be successfully used in a mud environment.Next,a pressure test of the corer was conducted.The results showed that under conditions of low pressure(8 MPa)and high pressure(25 MPa),the internal pressure of the corer remained stable for more than 1 h,indicating that the corer has good ability to maintain pressure.Therefore,the corer can be applied at deep coal mine sites.The results of this research can be used to promote the safe exploitation of deep coal mines and the exploitation of methane resources in coalbeds.

Pressure control method and device innovative design for deep oil in-situ exploration and coring

Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.

Wrinkling in graded core/shell systems using symplectic formulation

Wrinkles in flat graded elastic layers have been recently described as a timevarying Hamiltonian system by the energy method.Cylindrical core/shell structures can also undergo surface instabilities under the external pressure.In this study,we show that by treating the radial direction as a pseudo-time variable,the graded core/shell system with radially decaying elastic properties can also be described within the symplectic framework.In combination with the shell buckling equation,the present paper addresses the surface wrinkling of graded core/shell structures subjected to the uniform external pressure by solving a series of ordinary differential equations with varying coefficients.Three representative gradient distributions are showcased,and the predicted critical pressure and critical wave number are verified by finite element simulations.The symplectic framework provides an efficient and accurate approach to understand the surface instability and morphological evolution in curved biological tissues and engineered structures.

CFD-Based Optimization of a Diesel Engine Waste Heat Recycle System

A dedicated heat exchanger model is introduced for the optimization of heavy-duty diesel engines.The model is a prerequisite for the execution of CFD simulations,which are used to improve waste heat recovery in these systems.Several optimization methods coupled with different types of working fluids are compared in terms of exergy efficiency and heat exchanger complicity.The three considered optimization methods all lead to significant improvements in the R245fa and R1233zd systems with a comparatively low evaporation temperature.The optimal R245fa system has the highest efficiency increase(77.49%).The cyclopentane system displays the highest efficiency among the optimized ORC(Organic Rankine Cycle)systems,yet achieved by using a much heavier evaporator HEC(Heat Exchanging Core).In contrast,the 96.84%efficiency increase for the optimized R1233zd is achieved with only 68.96%evaporator weight.

Current status of outcome reporting in randomized controlled trials of traditional Chinese medicine for mammary gland hyperplasia: A systematic review

Objective:To assess outcome indicators in clinical trials and provide a reference for establishing a core outcome set to treat hyperplasia of mammary gland(HMG)with traditional Chinese medicine(TCM).Methods:Eight online databases were searched from their inception to December 31,2022,to assess outcomes reported in randomized controlled trials(RCTs)of HMG treated with TCM.The quality of the included studies was assessed according to the Cochrane Risk of Bias Assessment Tool.All outcomes were extracted,classified,and described.Results:A total of 8249 articles were initially retrieved.Of these,70 articles were eligible and involved 10618 participants with HMG.A total of 17 outcome indicators with a frequency of 271 times were involved and were collected according to six outcome domains.Conclusions:The core outcomes of RCTs of HMG treated with TCM are large and divergent.There are problems in evaluation standards,primary and secondary outcomes,TCM characteristic indicators,long-term prognosis,and standardization of reporting.It is recommended to strengthen the trial design and actively construct the core outcome sets with TCM characteristics for HMG.

Systematic evaluation of HBV BCP/PC mutations on the risk of hepatocarcinogenesis

Objective:To evaluate of the effects of mutations in BCP-A1762T/G1764A and PC-G1896A genes on hepatocarcinogenesis.Methods:Computer searches for PubMed,SCI,CNKI,VIP and WanFang Data databases were conducted to collect literature on the role of mutations in the disease process associated with HBV infection from database creation to July 1,2021.Two researchers independently screened the articles,extracted information and evaluated the quality of the studies.Review Manager software version 5.4 was used for Meta-analysis.Results:A total of 40 articles were included,with a total of 12423 cases and 3710 cases of hepatocellular carcinoma.Meta-analysis showed that mutations in BCP-A1762T/G1764A gene were associated with the disease process of HBV infection and promoted hepatocellular carcinogenesis.mutations in BCP/PC gene were significant in the process of HBV infection in BCP-A1762T/G1764A in HCC vs non-HCC[OR=4.05,95%CI=2.64~6.22],CHBC[OR=3.90,95%CI=2.13~7.17],CHB[OR=2.77,95%CI=1.78~4.32],LC[OR=1.64,95%CI=0.95~2.84],which were statistically significant;in PC-G1896A mutation HCC vs non-HCC[OR=1.49,95%CI=1.02~2.17],CHBC[OR=1.56,95%CI=0.89~2.72],CHB[OR=1.80,95%CI=1.17~2.77]were statistically significant,while the difference was not statistically significant when comparing HCC with LC(P=0.4).The BCP-A1762T/G1764A mutation in the B genotypes/genotyped versus the C genotype[OR=0.36,95%CI=0.20~0.64],with a statistically significant difference,and no statistically significant difference in the PC-G1896A mutation.BCP-A1762T/G1764A mutation in the C gene in HCC versus non-HCC[OR=3.71,95%CI=1.82~7.61]and PC-G1896A mutation in HCC vs non-HCC[OR=2.81,95%CI=1.34~5.91],the differences were statistically significant.Conclusions:Current evidence suggests that mutations in the BCP-A1762T/G1764A and PC-G1896A genes have a significant effect on the increased risk of hepatocellular carcinoma and are genotype dependent.However,due to the limitation of the number and quality of included studies,these findings need to be validated by more high-quality studies.

The Role of Trait Activation Theory in Occupational Behavior:A Systematic Review

The Trait Activation Theory(TAT)is widely regarded as the most influential personality theory approach in psychology.The purpose of this study is to analyze the TAT’s role in the contemporary workplace.Which personality traits are more likely to predict work success?Which characteristics should businesses prioritize throughout the recruiting and selection processes?According to the Trait Activation Theory,what is the significance of motivation in the workplace and how can employers find employees who can be more productive,efficient,and involved in the organization’s goals?A systematic review of past recent research was used to answer the questions raised above.Following the gathering and examination of multiple recent publications on the issue,it was determined that the use of this model had a favorable impact on individual and group performance,working relationships,manager job performance,and workplace creativity.

High-Inclination Coring of Chang-63 of the Yanchang Formation in Huaqing Oilfield, Ordos Basin: Implications for Ancient Flow Direction and Fracture Orientation

A promising method is to use coring of high-inclination well to find ancient flow direction and orient tiny natural fractures in massive sandstone of sandy debris flow. Determination of ancient flow direction can reduce the number of exploration wells, and orientation of natural fractures is of guiding significance to the deployment of water injection development well pattern. In Block X of Huaqing Oilfield, Ordos Basin, the cores of Chang 63 section were obtained from Well Y through 16 coring operations, with a total length of 105 m. Cores is oriented through drilling parameters, the number of cores, the angle between the core edge and horizontal bedding, the coincidence degree of core profile and directional flame structure. Therefore, the micro-fractures on the core are directional. The ancient flow directions of sandy debris flow were restored by load casting, groove casting, groove casting and imbricate structure. Our results show that the ancient flow directions of sandy debris flows were southwest, southeast, northwest, and west from bottom to top. The front of the Wuqi Delta is the main source of blocky sandstone with the best oil-bearing property. Affected by the topography of the lake bottom, the sandy debris flow turned locally in the northeast direction, and the sandy debris flow from this direction was formed. The NEE-SWW-trending fractures formed in the Yanshanian period are most developed in the Huaqing area, which should be considered in deploying the flooding well network. The north-south micro-fractures formed in the Himalayan period can improve the physical properties of tight sandstone, which is of great significance for tight sandstone reservoirs.

基于网格划分的常发性拥堵区域识别及演化模式分析

为准确识别常发性拥堵区域,分析其拥堵传播方向,疏通拥堵源头和阻断拥堵传播路径,提出一种基于网格模型和Fuzzy Core DBSCAN算法的常发性拥堵区域识别及演化模式分析方法。首先,对城市路网进行网格化处理,结合出租车GPS数据综合分析网格内车辆轨迹数量和轨迹加权平均速度,构建网格内部交通拥堵状态判别模型。然后,利用结合模糊集合论与DBSCAN算法扩展得到的Fuzzy Core DBSCAN算法识别常发性拥堵区域,选取拥堵规模、拥堵传播方向(即两个相邻网格之间的传播次数和传播概率)和关键网格3个指标来分析常发性拥堵的演化模式。最后,以黑龙江省哈尔滨市二环路范围内网格区域为例进行实证分析,结果表明:所识别出的常发性拥堵区域关键网格G(14,13)一周内拥堵传播到相邻网格共85次,其中27次(以31.8%的概率)沿西大直街向北传播至网格G(15,14);与百度地图开放平台数据相比,基于网格模型的拥堵判别结果准确率达85%;基于Fuzzy Core DBSCAN算法识别分析出的常发性拥堵区域拥堵演化模式与百度地图开放平台路况时变过程吻合。这表明融合Fuzzy Core DBSCAN算法与网格模型可有效识别常发性拥堵区域中关键网格的拥堵传播方向,能为制定科学合理的缓堵方案提供支撑。

Test of the Relative Permeability Curve of a Gas and Oil Condensate System and its Effect on the Recovery of Oil and Gas

The relative permeability curve has been measured with simulation oil (refined oil) and gas (nitrogen or air) at room temperature and a lowpressure, both of which are very important parameters for depicting the flow of fluid through porous media in a hydrocarbon reservoir. This basic measurement is often applied in exploitation evaluation, but the underground conditions with high temperature and pressure, and the phase equilibrium of oil and gas, are not taken into consideration when the relative permeability curve is tested. There is an important theoretical and practical sense in testing the diphase relative permeability curve of the equilibrium of oil and gas under the conditions of high temperature and pressure. The test method for the relative permeability curve is proposed in this paper. The relative permeability of the equilibrium of oil and gas and the standard one are tested in two fluids, and the differences between these two methods are stated. The research results can be applied to the simulation and prediction of CVD in long cores and then the phenomenon can better explain that the recovery of condensate gas rich in condensate oil is higher than that of CVD test in PVT. Meanwhile, the research shows that the relative permeability curve of equilibrium oil and gas is sensitive to the rate of exploitation, and the viewpoint proves that an improved gas recovery rate can properly increase the recovery of condensate oil.

面向现代GPU的Winograd卷积加速研究

卷积运算是现代卷积神经网络中必不可少的组成部分,同时也是最耗时的.为了解决卷积算子的性能问题,包括快速傅里叶变换(Fast Fourier Transform,FFT)和Winograd在内的快速卷积算法被提出. Winograd卷积可被用于提高小卷积核的推理性能,是目前卷积神经网络中的主流实现方法 .然而,Winograd卷积在许多高度优化的深度神经网络库和深度学习编译器中的实现比较低效.由于Winograd卷积的四个阶段的复杂数据依赖关系,面向GPU对其进行优化非常具有挑战性.本文针对现代GPU体系结构优化了Winograd卷积算子的性能.本文提出了Winograd计算阶段的等价变化及其利用Tensor Core进行计算的无同步实现,并进一步提出了利用不同GPU内存层级的部分计算核融合方法 PKF(Partial Kernel Fusion).基于张量虚拟机(Tensor Virtual Machine,TVM)和代码重构器PKF-Reconstructor(Partial Kernel Fusion Reconstructor),实现了高性能的Winograd卷积.对真实应用中卷积神经网络的卷积算子的评估表明,与cuDNN相比,本文所提算法实现了7.58~13.69倍的性能提升.

Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres

Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres.This architecture,comprising SiO_(2)as the core,MXene as the intermediate layer,and MoS_(2)as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal process.This complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2)nanosheets.Notably,the synergistic combination of SiO_(2)and MoS_(2)with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance matching.Therefore,the core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 GHz.This work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.”

基于DWC PCIE Core的数据传输系统设计

在铁路信号系统中,为有效减少铁路信号系统设备CPU资源占用率,设计一种基于DWC PCIE Core的数据发送与接收系统。该系统采用内嵌ARM Cortex-A9双核的FPGA开发板套件,利用FPGA的灵活性和可扩展性,采用可配置的PCIE硬核IP模块以及以太网硬核IP模块。该系统主要介绍Host PC与FPGA之间基于PCIE 2.0的DMA数据传输以及FPGA之间基于GMAC的以太网数据传输,通过PCIe总线、以太网基于DMA模块实现数据高速可靠传输。