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As shale oil exploration and development intensifies， the experimental technologies for shale oil development have been continuously improved while inheriting the experimental technologies and methods of conventional reservoirs and shale gas reservoirs， and a set of experimental technology systems of reservoir physics and flow mechanisms has been initially formed， which provides strong technical support for geological evaluation of shale reservoirs， reservoir engineering optimization design， and enhanced oil recovery. The development status of six experimental technologies in China and abroad， including porosity， permeability， oil-water saturation， wettability， relative permeability， and imbibition， was systematically summarized. In view of the characteristics of continental shale oil， such as low maturity， strong heterogeneity， and well-developed lamina and micro-fractures， the measurement methods and principles， key influencing factors， control conditions of experiments， advantages and disadvantages and technical applicability of experiment methods were analyzed. The main problems， development trends， and research direction of these experimental technologies were put forward. The results show that ① unifying the cleaning agent and cleaning time of rock samples is the key to improving the comparability of different measurement methods of porosity， and nuclear magnetic resonance measurement of porosity is the technological development direction to meet the needs of rapid analysis in mining fields； ② the irregular and multi-directional permeability measurement technology capable of simulating formation pressure changes is the future technological development direction； ③ the alcohol soaking method and two-dimensional nuclear magnetic resonance （T1-T2） method are the technological development direction of the determination of shale oil-water saturation， but they still face the problem of the influence of clay bound water and adsorbed oil on the determination accuracy； ④ the droplet morphology method is one of the future development directions of measurement technology of shale reservoir wettability， which requires further research and unified standards in experimental methods and comprehensive evaluation methods for surface wetting and spontaneous imbibition processes； ⑤ the combination of experimental measurement and numerical method is an effective way to obtain the relative permeability of shale reservoirs， and the micro-oil and water metering， end-effect correction， as well as technologies and methods considering the time-varying pressure are the key directions； ⑥ pressure imbibition measurement method should be used to evaluate imbibition effect and optimize well kill time in elastic development after fracturing. Pressure imbibition measurement methods based on nuclear magnetic resonance T2 spectrum， stratification T2 spectrum， and T1-T2 spectrum will be one of the essential technological development directions.

A piston lattice structure design method based on reliability topology optimization is proposed for the lightweight design of internal combustion engine pistons, which is decomposed into two parts of reliability analysis and deterministic topology optimization to be solved separately. A mathematical model for the reliability topology optimization of the piston lattice structure was established considering the minimized mass as the objective function and the maximum stress as the constraint. The failure probability constraint was transformed into a reliability index constraint according to the first second-order moment method, and then the random variables were transformed into standard normal variables, and the random variables were corrected and designed for deterministic topology optimization according to the sensitivity information of the random variables relative to the performance index. Finally, a comparative study of deterministic lattice design and reliable lattice design was conducted with a certain type of engine piston as an example. The results show that compared with the deterministic design, the reliability piston lattice model has more reliable performance when considering the influence of random variables. And the mass of lattice model is reduced by 11.8% compared with the original piston model, which meets the design requirement of piston lightweighting.

ObjectiveTo observe the effect of respiratory training with Liuzijue on pulmonary function, activities of daily living and quality of life in patients with ischemic stroke and hemiplegia.MethodsA total of 76 patients with ischemic stroke and hemiplegia who were hospitalized in the Second Affiliated Hospital of Fujian Medical University and the Jinjiang Hospital of Traditional Chinese Medicine Affiliated to Fujian University of Traditional Chinese Medicine were recruited from March to September 2019. The patients were divided into control group (n=38) and experimental group (n=38) using a random number table method and according to the order of admission. The control group received routine treatment, nursing care, and early rehabilitation training; in addition to these interventions, the experimental group received Liuzijue respiratory training, and the patients were instructed with nasal inspiration and mouth expiration method, and the expiration was carried out in accordance with the Liuzijue sequence of "xu" "he" "hu" "si" "chui" "xi" 30 min/time, once a day, 5 days a week, lasting for 12 weeks. The forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), peak expiratory flow (PEF) rate and maximum voluntary ventilation (MVV) volume of the two groups were evaluated by portable pulmonary function meter before and after the intervention; the modified Barthel index (MBI) was used to evaluate activities of daily living; the stroke impact scale (SIS) was used to evaluate the quality of life.ResultsBefore the intervention, there was no statistical difference in the FVC, FEV1, PEF, MVV, MBI, and SIS scores between the two groups (P>0.05). After 12 weeks of intervention, the scores of the FVC, FEV1, PEF, MVV, MBI, SIS in both groups improved significantly compared with those before intervention, and the differences were statistically significant (P1, PEF, MVV of the experimental group were (2.63±0.68) L, (2.33±0.68) L, (4.49±1.39) L/s, (44.08±13.89) L/min respectively, which were better than those in the control group (2.31±0.50) L, (2.03±0.48) L, (3.79±1.46) L/s, (34.74±15.21) L/min, and the differences were statistically significant (PPP

Rotating sleeve distributing-flow system is a new-type distributing-flow system,overcoming the shortcomings of traditional valve-type flow distribution systems such as large volume,loose structure,and low volumetric efficiency. The cam groove profile of the rotating sleeve directly affects the kinematics characteristics of rotating sleeve distributing-flow system. In this paper,by analyzing the self-locking characteristics of the sinusoidal cam groove profile,four new types of cam groove profiles are proposed,the kinematics analysis of rotating sleeve and drive pins under the four cam groove is performed. The results showed that: the amplitude of the angular velocity and angular acceleration of the line cam groove profile rotating sleeve is the smallest,which is 203. 1 rad/s and 4. 961 × 10~4 rad/s~2,respectively,and there are two impacts in one cycle; The radial speed and acceleration of drive pin under line cam groove profile is the smallest,which is -0. 387 m/s and 115. 0 m/s~2,respectively,and there is no impact during cycles. So,the line cam groove profile is the best choice.

BackgroundThe activation method is taken to measure the in-core distribution of neutron spectrum for the designed 10 MW solid-fuel thorium molten-salt reactor (TMSR-SF1). The neutron activation foil sample is loaded outside the reactor and quickly transported to the measurement position in the reactor through the transmission device for irradiation, and then is transferred outside of reactor to the energy spectrum samples for de-spectrographic analysis.PurposeIn order to realize the rapid entry and exit of the neutron activation foil sample into and out of the reactor, a pneumatic conveying system with double-layer casing is designed in this research.MethodsThe principle of the conveying system and the structure of the double-casing tube were adopted in this study. ANSYS Fluent software and 6DOF dynamic grid technology were used to analyze the movement and stress of the sample under different pipe gaps, so as to determine the sample pipe gap value. Then the flow parameters and gas-solid two-phase flow resistance of the conveying system were calculated in detail using the pneumatic conveying theory. Finally, a prototype was developed for experiments to verify the principle of the conveying system.ResultsThe analysis results showed that the sample speed is decreased with the increase of the pipe gap. The experiments results show that the velocity of the sample and the pressure loss of the gas-solid two-phase flow increase with the increase of the gas flow rate. Under the same flow rate, the experimental speed of the sample movement and the pressure loss of the gas-solid two-phase flow are in good agreement with the theoretical calculations.ConclusionsThe pneumatic convey system with double-casing tube can be applied to transport the sample into and out of the reactor, and the theoretical calculations values of pneumatic conveying parameters in this study are reliable.

According to the problems that loose structure,large throttling loss and Efficiency is affected by the operating frequency,when reciprocating plunger pump uses valve type orifice structure.Rotating-sleeve distributing-flow system for reciprocating plunger pump was put forward,which has the advantages of simple and compact structure,small throttling loss,stable work and assignment without delay.Described the working principle of rotary sleeve type flow system,established the kinematics model of three different cam groove liner,analyzed kinematics characteristics influence of distributing-flow system that three cam groove type rotating-sleeve effect on,and analyzed the shear strength of the drive pin.The numerical results showed that compared with the other two linear cam grooves,the angular velocity and angular acceleration of sinusoidal cam groove rotating-sleeve has smallest size and magnitude,and has no inflection point and step,and the rotating-sleeve can rotates relatively stable,the impact force of each parts of distributing-flow system is smallest.

The structure and working principle of the plunger pump of the gear- linked cylinders hydraulic engine is put forward creatively for the issues that loose structure,more throttling lose,low efficiency and affected highly by working frequency that appearing in traditional plunger pump. And the structure and working principle of the gear- linked cylinders hydraulic engine are expounded. The plunger pump of the gear- linked cylinders hydraulic engine is a kind of liner reciprocating plunger pump that direct convert the indicated work into fluid pressure,it has advantages of compact structure and high volumetric efficiency. The kinematics research of the plunger pump of the gear- linked cylinders hydraulic engine provides reference for the later dynamics analysis,flow stress analysis,cam slot line optimization and prototype trial.

While the deprivation of rights is among the roots of poverty, an analysis of issues pertaining to rights alone is insufficient for a proper understanding of and solution to the complex problem of poverty. Combatting poverty is essentially an issue of governance. China has made enormous advances in poverty alleviation in the past seven decades, thanks to the formation, perfection, and development of a unique model that allowed the state to identify the particularities of the problem of poverty during different periods and implement suitable measures accurately and efficiently. China's success in combatting poverty has relied on the state's strategic promotion, the CCP's mobilization and organization, and the policies of prioritizing villagers' interests and paying equal attention to both poverty alleviation and economic growth. 摘要: 贫困构成权利实现的障碍，权利剥夺和失败是造成贫困的根源。然而，贫困问题的复杂性使得贫困的权利分析，并非解决贫困问题的适当方法。摆脱贫困，需要从治理的观点看。建国70年来，中国农村贫困治理获得了显著成效。结合国家财政实力与不同时期贫困特质情况，采取有效瞄准机制与减贫措施，农村贫困治理模式得以逐渐建立、完善与发展，从而让农村贫困治理始终保持着边际不减的态势。中国农村减贫事业所以取得成功，根本上依赖于国家战略的高位推动、中国共产党强大的组织动员能力、对农民主体地位的尊重以及始终坚守在发展中减贫。中国农村贫困治理的成功经验，为世界减贫事业贡献了中国方案与中 国智慧。 [ABSTRACT FROM AUTHOR]

Considering the topology-dependent heat source problems in the heat conduction topology optimization design, the mathematical model of multi-phase material topology optimization of heat dissipation structures was constructed. The objective function was assigned to dissipation of heat potential capacity, combined with volume fraction constant conditions. The variable density theory was introduced to represent the multi-phase material interpolation model based on ordered-solid isotropic microstructures with penalization (Ordered-SIMP) methodology. Then the sensitivity analysis of topology-dependent and topology-independent heat sources was executed respectively, and the iteration format of design variables were solved by optimization criterion. The partial differential equation filter method was implemented to suppress numerical instability in the optimization processes. Through the 2D/3D numerical models, the meaningful conclusions of topology-dependent heat sources, topology-independent heat sources and coupled heat sources were illustrated under different boundary conditions. The proposed method is effective and feasible in solving the multi-phase material topology optimization problem of topology-dependent heat sources. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effectiveness of Tang's arthroscopy approach in treatment of anterior and posterior ankle impingement syndrome., Methods: Between August 2010 and September 2017, 92 patients with anterior and posterior ankle impingement syndrome were retrospectively analyzed. There were 58 patients were treated with Tang's arthroscopy approach under floating decubitus (group A) and 34 patients were treated with standard anterior and posterior approaches (group B). There was no significant difference in gender, age, body mass index, side, disease duration, preoperative American Orthopaedic Foot and Ankle Society (AOFAS) score, and preoperative visual analogue scale (VAS) score between the two groups ( P >0.05).The operation time, AOFAS score, VAS score, and Roles-Maudsley score were recorded to evaluated the pain and function of the ankle, and patient subjective satisfaction. The X-ray film and MRI at 12 months were used to observe the ankle impingement., Results: Median operation time of group A was 50.5 minutes ［95%CI (49.3, 54.6)］, which was significantly shorter than that of group B ［88.5 minutes, 95%CI (76.5, 92.8)］ (Z=-4.685, P =0.000). All incisions in group A healed by first intention; while the incisions of 2 cases in group B delayed healed after debridement. The follow-up time of group A was (54.7±18.8) months, while that of group B was (55.4±17.9) months, and there was no significant difference between the two groups ( t =-0.178, P =0.859). The lateral X-ray films at 12 months showed that the talus process was removed incompletely in 2 cases (3.4%) of group A and 1 case (2.9%) of group B. There was no significant difference in the incidence between the two groups (χ 2 =0.014, P =0.699). At last follow-up, the AOFAS scores were 83.1±6.6 in group A and 85.2±6.4 in group B; the VAS scores were 1.3±1.1 in group A and 1.6±1.0 in group B. The AOFAS and VAS scores at last follow-up were superior to preoperative ones ( P <0.05), but there was no significant difference between the two groups ( P >0.05). The median subjective satisfaction score of group A was 2.0 ［95%(1.4, 1.7)］, which was better than that of group B ［2.0, 95%(1.6, 2.2)］ ( Z =-2.480, P =0.013)., Conclusion: Arthroscopic treatment of anterior and posterior ankle impingement syndrome through Tang's approach can shorten the operation time, simplify the procedures, and obtain good effectiveness and patient satisfaction.

Electrocardiogram (ECG) signals are easily disturbed by internal and external noise, and its morphological characteristics show significant variations for different patients. Even for the same patient, its characteristics are variable under different temporal and physical conditions. Therefore, ECG signal detection and recognition for the heart disease real-time monitoring and diagnosis are still difficult. Based on this, a wavelet self-adaptive threshold denoising combined with deep residual convolutional neural network algorithm was proposed for multiclass arrhythmias recognition. ECG signal filtering was implemented using wavelet adaptive threshold technology. A 20-layer convolutional neural network (CNN) containing multiple residual blocks, namely deep residual convolutional neural network (DR-CNN), was designed for recognition of five types of arrhythmia signals. The DR-CNN constructed by residual block local neural network units alleviated the difficulty of deep network convergence, the difficulty in tuning and so on. It also overcame the degradation problem of the traditional CNN when the network depth was increasing. Furthermore, the batch normalization of each convolution layer improved its convergence. Following the recommendations of the Association for the Advancements of Medical Instrumentation (AAMI), experimental results based on 94 091 2-lead heart beats from the MIT-BIH arrhythmia benchmark database demonstrated that our proposed method achieved the average detection accuracy of 99.034 9%, 99.498 0% and 99.334 7% for multiclass classification, ventricular ectopic beat (Veb) and supra-Veb (Sveb) recognition, respectively. Using the same platform and database, experimental results showed that under the comparable network complexity, our proposed method significantly improved the recognition accuracy, sensitivity and specificity compared to the traditional deep learning networks, such as deep Multilayer Perceptron (MLP), CNN, etc. The DR-CNN algorithm improves the accuracy of the arrhythmia intelligent diagnosis. If it is combined with wearable equipment, internet of things and wireless communication technology, the prevention, monitoring and diagnosis of heart disease can be extended to out-of-hospital scenarios, such as families and nursing homes. Therefore, it will improve the cure rate, and effectively save the medical resources.

Objective To evaluate the expression of circadian locomotor output cycles kaput (CLOCK) and its effects on cell growth in hepatocellular carcinoma (HCC). Methods The expression of CLOCK in 158 pairs of human HCC tissues and matched noncancerous samples was detected by immunohistochemical (IHC) staining. The expression of CLOCK in HCC patients was also verified using the data from GEO and TCGA (a total of 356 cases). The relationship between CLOCK expression and clinicopathological features of HCC patients was analyzed by single factor statistical analysis. Kaplan-Meier survival curves of HCC patients were drawn to study the relationship between the expression level of CLOCK and the survival state. The effect of CLOCK on the growth of HepG2 cells was detected by MTS assay. Results The expression of CLOCK in HCC tissues was significantly higher than that in the adjacent tissues, and the up-regulation of CLOCK expression in HCC tissue was also confirmed in the public data of HCC (356 cases). HCC patients were divided into low CLOCK expression group and high CLOCK expression group. Univariate analysis showed that the expression of CLOCK was related to tumor size, TNM stage, and portal vein invasion in HCC patients. HCC patients with low CLOCK expression had longer overall survival time and relapse-free survival time than those with high CLOCK expression. The proliferation of cells significantly decreased after the expression of CLOCK was knocked down in HepG2 cells. Conclusion The expression of CLOCK in HCC tissues was much higher than that in normal liver tissues, and the high expression of CLOCK indicated the poor prognosis. The knockdown of CLOCK in HCC cells could inhibit the proliferation of HepG2 cells.

Meridian theory plays an important role in the guidance of clinical practice of acupuncture and moxibustion. Since the publication of Zhenjiu Jiayi Jing ( A-B Classic of Acupuncture and Moxibustion ), the meridian theory has been developed. In the paper, in view of complex science, the topological properties of acupoint-symptom network were analyzed quantitatively by taking acupoint as node and indication as the connection, such as high clustering coefficient and the small world effect. It was the first time to give the abstraction for the topological proof of the high efficiency information transmission property of acupoint-symptom network meridian system at different times. Its quantitative and digitalized significance was analyzed on the development of meridian theory under the complex scientific background so as to provide a new thought and method for the study of meridian theory and acupuncture modernization.