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The traditional differential evolution（DE） algorithm balanced global exploration and local exploitation inadequately, and had problems with easily falling into local optimal solutions, low solution accuracy and slow convergence speed. Therefore, this paper proposed a differential evolution algorithm based on random neighborhood mutation and optimal opposition-based learning（RNODE） and analyzed for its complexity. Firstly, the algorithm generated a random neighborhood for each individual in the current population, and used the global best individual to guide the neighborhood best individual to generate a composite basis vector, combined with an adaptive update mechanism of the control parameters to constitute a random neighborhood mutation strategy, which enabled the algorithm maintained its exploration ability and guided the population towards the optimal direction. Secondly, to further help the algorithm jump out of the local optimum, the algorithm performed the optimal opposition-based learning strategy on the poorer individuals to expand the search area. Finally, this paper compared RNODE with 9 algorithms to verify the effectiveness and advancement of RNODE. The experimental results on 23 benchmark functions and 2 real-world engineering optimization problems show that the RNODE algorithm has a higher convergence accuracy, faster speed and a greater stability. [ABSTRACT FROM AUTHOR]

Reducing the effect of unwanted vibrations is an important topic in many engineering applications. In this paper we describe some recent developments in the area of passive vibration mitigation. This is based on a new device called the inerter which can be exploited in a range of different contexts. In this paper we consider two recent examples; (i) where a flywheel inerter is combined with a hysteretic damper, and (ii) in which a pivoted bar inerter is developed for a machining application. In both cases, experimental test results show that the devices can outperform existing methods. [ABSTRACT FROM AUTHOR]

Currently, spatiotemporal information, positioning and navigation have become important new infrastructures. Driven by general artificial intelligence, the era of intelligence led by large models has arrived. The increasingly powerful large models will play a more and more important role in the intelligent processing and applications of spatiotemporal information. First, this paper uses large models as the research paradigm and summarizes the current status and progress of large models in intelligent processing of spatiotemporal information in surveying and mapping. In addition, it analyzes the challenges faced by large models in intelligent processing of spatiotemporal information in surveying and mapping. We elaborate three key technologies in spatiotemporal information large models for surveying and mapping, including multi-modal fusion and understanding architecture design, prompt engineering optimization by fine-tuning, and human-in-theloop guidance for decision-making. Finally, the depth of industry understanding, data security risks, content credibility, and training deployment cost optimization are addressed to predict the development trend of spatiotemporal information large models. [ABSTRACT FROM AUTHOR]

Based on the analysis of operation system capability testing and evaluation, this paper studies the data resource system of operation system capability testing and evaluation from operation, business and engineering aspects. A 3-View Data resource framework is presented. And some suggestions on data resource construction are given. The research can help to clarify the data needs, improve the consistent understanding of joint operation system capability evaluation data, and promote the development of the data resource and data integrated service platform. [ABSTRACT FROM AUTHOR]

In order to solve the problem of bypassing detection methods for DNS covert channel（DCC） traffic deformation strategies, this paper proposed a DCC detection method based on traffic slice. In this method, the traffic of the experimental environment was firstly divided into batches based on the sliding window, and then obtained the traffic slice based on the aggregation of each host-end IP. Each slice contains DNS packets and Web packets belonging to the same host in a short time span. Then, for the DNS data volume, DNS request behavior, DNS response behavior, and association behavior correlation behavior with WEB of DNS in the slice, it implement DCC-detection-oriented feature engineering and create detection models on this basis. Comparative experiments show that the detection accuracy of the constructed DCC detection model on the conventional DCC traffic datasets is 99.83%,and the false positive rate is only 0.08%.On the deformed DCC traffic datasets with six types of different traffic deformation strategies, the detection ability of the DCC detection model is more than 95% on average, which is better than the other detection schemes. It proves that the proposed method is effective in dealing with DCC traffic deformation. Moreover, the proposed method, which can effectively detect DCC communication within a single traffic slice, is a detection method with good real-time performance. [ABSTRACT FROM AUTHOR]

To improve the local mining and global search ability of quantum-behaved particle swarm optimization algorithm ( QPSO), this paper proposed an improved QPSO algorithm( DSQPSO). DSQPSO algorithm introduced the double strategies co-evolution to adjust the particle position update formula. Firstly, in order to fully reflect the advantage of individual exploration and the characteristic of collective guidance, this paper put forward two kinds of ideas of attraction points to achieve better integration of individuals and the swarm as well as information exchange. Secondly, it redefined the search scope of the particle through considering the relationship between the optimal average position and the global optimum and individual's historical optimum respectively. Moreover, in the iterative process, DSQPSO used the random perturbation mechanism to adjust the global optimal position in order to help the diversity of the swarm to be preserved. Based on 18 test functions, this paper compared DSQPSO with PSO, QPSO, RQPSO and LQPSO in convergence accuracy and robustness. Furthermore, in terms of the optimization results, it compared the improved algorithm with eight intelligent algorithms on two practical engineering optimization problems. Experiments indicate that whether in benchmarking or in engineering application, DSQPSO has obvious advantages in calculation precision and convergence effect. [ABSTRACT FROM AUTHOR]

In order to further promote the research and application of BIM technology in caisson gravity wharf project, this paper takes the No. 9 and No. 10 berths project of Dalanping South Operation Area, Dalanping Port Area, Qinzhou Port as an example, applies BIM technology to the construction management of traditional hydraulic wharf, introduces BIM technology in the construction process, and establishes a three-dimensional information model. On this basis, the comprehensive application of BIM technology was carried out for the project, and the effective combination of BIM technology and site construction was realized. With the advantages of visualization and informationization of BIM technology, engineering quantity statistics, construction progress simulation, design optimization, project results display and other work can be realized. BIM technology can empower traditional hydraulic projects, improve management level, enhance performance ability, and obtain good economic and social benefits, which provides a reference for similar projects and has certain promotion and reference significance. [ABSTRACT FROM AUTHOR]

In order to improve the technical level of wharf construction, solve the problems of large tidal height difference, underfill caisson packing, irregular fender groove and different positions, and improve the quality of the project entity, this paper analyzes the fender groove construction in No.9 and No.10 berths project in Dalanping South Operation Area of Qinzhou Port, discusses the construction methods and key points of operation and formwork technology, and puts forward specific technical measures, such as mixed adjustable formwork, prefabricated bottom formwork, water -stop steel box, etc. It has accumulated the field construction experience of the fender groove of gravity wharf, ensured that the concrete at the fender groove meets the design and specification requirements, and effectively improved the quality of engineering entities. [ABSTRACT FROM AUTHOR]

Since improvement of ultra-soft soil ground encounters the shortage of sand resources in Tianjin coastal area, non-sand blanket vacuum preloading method becomes an important substitute approach to solve the dilemma. Under such a background, DB/T 29-263—2019 Technical Standard of Non-sand Blanket Vacuum Preloading Method for Soft Soil Improvement in Tianjin was issued and implemented on July 1st in 2019. This paper compares the standard DB/T 29-263—2019 with the industrial standards, JTS 147—2017 Code for Foundation Design on Port and Waterway Engineering and JTS206—2017 Code for Foundation construction on Port and Waterway Engineering, and further analyzes the main differences in the design and construction with the conventional vacuum preloading method and the non-sand blanket vacuum preloading method for a purpose to help engineering practitioners better understand DB/T 29-263—2019 in the promotion of application of non-sand blanket vacuum preloading method. [ABSTRACT FROM AUTHOR]

The cutting process finite element simulation technology is a numerical method to simulate the cutting process, which can investigate various physical mechanisms caused by material removal during the cutting process. It has significant advantages in optimizing cutting parameters, improving machining quality, and reducing research costs. The significantly investigate objective is how to make the finite element simulation of cutting process more consistent with actual cutting process, so numerous research on finite element simulation technology for cutting has been carried out both domestically and internationally, and the relevant achievements have been applied in engineering. This paper provides an overview of the basic principles, advantages, and development trends of geometric simulation and physical simulation in cutting process finite element simulation. It systematically summarizes the development of constitutive models and mesh partitioning by domestic and foreign scholars to improve the accuracy and efficiency of cutting machining finite element simulation. On this foundation, the research progress of the combination of geometric and physical simulation methods is summarized. Finally, the important issues and future development trends of finite element simulation technology for cutting machining are envisioned. [ABSTRACT FROM AUTHOR]

This paper discusses the necessity and urgency of the exploration and practice of the applied talent training system of chemical materials in local universities. We expound the renewal of personnel training mode, the setting of characteristic curriculum, and the innovation of school-enterprise cooperative education mechanism. It also updated the orientation of emerging engineering application-oriented talent training “grounded and close to industry”. Subsequently, we explored and practiced the “double 4-6” application-oriented talent training model. We further reconstruct the curriculum system matching the training of applied talents. The “three - three system” has been implemented for industry-university-research collaborative education mechanism. Finally, the new model is explained with fruitful results. [ABSTRACT FROM AUTHOR]

When the load behind an existing revetment increases, it is often required to reinforce the existing structure to ensure that its stability meets the new usage requirements. The mainstream stability analysis concept requires that the lowest slip arcs stability coefficient should be higher than a specific value, and neglects factors such as the status-quo stability of an existing revetment and the differences of slip arcs at different positions, which may easily lead to over -design. Based on a practical engineering case, the paper classifies and discusses slip arcs at different locations of an existing revetment and determines the stability criteria respectively, to ensure that the judgment of stability is reasonable and reliable, and there in forcing design is economical, reasonable and highly targeted. [ABSTRACT FROM AUTHOR]

Aiming at the problems of view limitation, high cost and low efficiency in the monitoring and management of TSHD, the trajectory clustering algorithm for TSHD is studied. This paper proposes a hierarchical multi-clustering algorithm based on the public trajectory data for the first time, which solves the difficulties in setting the weight of multiple parameters at one time and realizes a fast trajectory clustering of TSHD. The results show that the method is reasonable and feasible, and can quickly and effectively identify the trajectories of TSHD. The research results may be applied to the identification of abnormal trajectories of TSHD, monitoring and management of the operations of TSHD, and the analysis of major waterway engineering and works. [ABSTRACT FROM AUTHOR]

In this paper, we collected, summarized, and analyzed the available data of 143 transportation immersed tunnels at home and abroad, and analyzed the current state of the immersed tunnel engineering in the world from the aspects of construction quantity, construction length, construction speed and construction difficulty. Based on the quantifiable indexes of tube volume, tube number, water depth and buried depth, the evaluation formula of construction difficulty of immersed tunnel was put forward for the first time. Finally, based on the number of monographs, patents and papers, we analyzed and evaluated the scientific and technological development status of immersed tunnel in China. [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings of crow search algorithm ( CSA), this paper proposed a crow search algorithm using multi-mode flight ( MFCSA) . Based on the strength of foraging ability, the algorithm divided the population into two groups: strong and weak foraging ability. Those with strong foraging ability adopted the strategy of trailing and tracking the optimal target of the current group, and flied to the vicinity of the current optimal position of the group under the guidance of the group information to carry out search activities, which enhanced the local exploitation ability of the algorithm. Those with weaker foraging ability adopted the two strategies of observing and learning the foraging methods of the strong, and flying away quickly when encountering danger, the former could improve the global exploration ability of the algorithm, and the latter could maintain the diversity of the population. Through the numerical experiment simulation of 15 benchmark test functions and 2 engineering application problems, the results show that the MFCSA has better performance in optimization accuracy, convergence speed, etc., enhances the ability to avoid falling into the local optimum, and has better stability. [ABSTRACT FROM AUTHOR]

During the construction of the island and tunnel project of Hongkong-Zhuhai-Macao Bridge, a series of world-class engineering challenges were successfuly borken through by following the general path of synchronized technology and management, and established our own sea-crossing immersed tunnel technology system with independent intellectual property rights. In this paper, innovation cases in HZMB and the Shenzhen -Zhongshan Link were discussed, and the circulating improvement law of "Technology+Management" in engineering construction was revealed, which has supported the iterative upgrade of technologies, and promoted breakthroughs in engineering management thoughts and high -quality development in project construction. It is of practical significance to achieve the goal of building high-quality projects, and can also provide reference for technical and management professionals. [ABSTRACT FROM AUTHOR]

The structure characteristics of air-dissolving device directly affect the gas-liquid mass transfer rate and air-dissolving efficiency in a pressurized dissolution type microbubble generator. Considering the significant role of air-dissolving device, the air-dissolving mechanism, the structure of the air-dissolving device and the evaluation method were systematically presented in this paper. The air-dissolving mechanisms such as, classical mass transfer theory model, the improved classical mass transfer theory model and the eddy current theory model, were briefly introduced. Then, the structure characters and working principles of typical air-dissolving device, such as packing type, jet type, inner cylinder overflow type, spiral-flow type and swirling type, were summarized. After that, the corresponding research methods of the air-dissolving device in practical engineering were systematically presented. All in all, the research of air-dissolving mechanism was still on the way, which only provided guidance for the air-dissolving device design at a macro level. The mass transfer rate was hard to quantitatively characterize when combining the air-dissolving mechanism and air-dissolving device. Thus, more efforts should be made to strengthen the research of universal theoretical model, and promote the coordinated development of air-dissolving mechanism and air-dissolving device. [ABSTRACT FROM AUTHOR]

For the reinforcement of soft marine deposit, relying on the main reclamation works of the Hong Kong Airport three runway system project (hereinafter referred to as the Hong Kong three runway project), the on-site trial process for high pressure jet grouting piles was carried out, and the advanced multi-functional high pressure jet grouting rig from Italy was adopted, which has high degree of construction automation, good quality of jet grouting pile and fast work efficiency. This paper focuses on the influence of cement dosage, curing age, etc. on the strength on-site cement soil, as well as the strength proportion of indoor cement soil at different ages. It provides a good engineering and technical reference for the popularization and application of high-pressure jet grouting pile reinforcement method in coastal soft soil foundation in Hong Kong. [ABSTRACT FROM AUTHOR]

Intelligent mine filling is an important part of unmanned and intelligent mine construction. Aiming at the lack of a systematic understanding of how to construct intelligent mine filling and what functions the intelligent control system should have in the domestic, this paper analyzes the key points of mine filling control and designs the "cloud, edge and end" three layer intelligent control system for mine filling based on the industrial Internet platform. Combined with the engineering case of Wushan copper mine′s unclassified tailings paste filling system construction, the intelligent control system has been introduced in detail, which can provide reference for the realization of intelligent filling construction in domestic mines. [ABSTRACT FROM AUTHOR]

At present, there is no general theoretical calculation method for calculating the wave force of wave-retaining wall at the top of slope breakwater. In this paper, the commonly used formulas for calculating wave force were analyzed and compared with the conclusions of physical model test of practical engineering. The analysis results show that the wave force calculated by Pedersen method is consistent with the experimental results, and is a reliable way to calculate wave force at present. The results obtained by the wave force calculation method on the current hydrological code are generally small(compared with the physical model test results). The above conclusions can provide a certain reference for similar projects. [ABSTRACT FROM AUTHOR]

This paper discusses the design scheme and construction method of sealing water by compaction grouting at the seepage position of temporary cofferdam of dry dock in Dalian Bay subsea tunnel, which achieves good water stop effect and meets the operation requirements during the dry dock construction period. The data and experience accumulated in construction can provide reference for similar engineering conditions. [ABSTRACT FROM AUTHOR]

The secondary outfitting work of the immersed tube needs to be carried out in a floating state. The measuring tower is an important outfitting part in the secondary outfitting. Its calibration of the precise position of pipe sections is related to the success of the floating installation of the immersed tube. Since the pipe sections are floating on the sea surface, it poses a huge challenge to the calibration of the measuring tower. In this paper, the calibration methods of measuring towers in the floating state of five pipe sections were introduced, and their advantages and disadvantages were analyzed, and the calibration methods used in the Dalian Bay subsea tunnel project were analyzed. The results show that the accuracy of the GNSS synchronization calibration method can reach 2 cm on the plane, and that of total station floating calibration method can reach 1 cm on the plane, which meets engineering needs. The results can provide reference for other similar marine engineering calibration measurements. [ABSTRACT FROM AUTHOR]

The standard whale optimization algorithm( WOA ) and some derivative algorithms are studied and experimented to solve the problem of poor results of some examples. It is proved that there is a zero searching preference trap in the " encircling" process of WOA. In addition, the unbalanced search characteristics of chaos optimization algorithm( COA) make it difficult to reconcile the chaos initial population and swarm intelligence optimization process. In order to improve the above defects, this paper selected two chaotic systems and bubble net hunting strategy, and designed a set of fusion optimization algorithm. The algorithm adopted the baseline adaptive oscillation group partition strategy based on fitness to guide the group behavior pattern, gave full play to the role of chaotic system, and balanced the exploration and convergence performance. It used the new algorithm to solve the general/improved examples and engineering application cases. It 's obviously that the performance of the algorithm is better than the contrast group algorithm,and there is no searching preference. [ABSTRACT FROM AUTHOR]

Compared with contracting engineering projects in China, contracting international engineering projects is affected by many factors, with great risks and uncertainties. Risk control should be paid attention to and effective risk prevention should be carried out in bidding stage. In this paper, we summarized the common risks of international project bidding, and expounded the procedures and principles of international project pre - bidding organizations, and introduced the key points and countermeasures of risk prevention and control by studying bid documents and on -site investigation combining with a large number of practical engineering cases, so as to provide reference for Chinese enterprises who participate in international project bidding. [ABSTRACT FROM AUTHOR]

In this paper, we put forward the talent goal of Luban workshop school-enterprise cooperation industry-education integration to cultivate localized excellent engineers, and designed a three -dimensional curriculum support system and the training model of " Luban workshop" school -enterprise cooperation industry -education integration localization excellent engineers, and discussed the implementation path combined with practical experience. The research results can alleviate the plight of the demand for localized talents in the international engineering industry, and provide some practical experience and theoretical guidance for the cultivation of localized talents in the international engineering industry. [ABSTRACT FROM AUTHOR]

The construction environment of immersed tunnel is complex, the construction organization and implementation are difficult, and the operation safety risk is high. In this paper, we introduced the establishment and application of the special risk assessment system for immersed tunnel engineering, the establishment of the safety risk assessment system in the construction stage can enhance the safety risk awareness, standardize the risk management process, and guide the scheme and plan preparation, effectively reduce the construction risk and strictly prevent the occurrence of serious accidents through qualitative and quantitative construction safety risk assessment. The practice shows that the application of risk assessment system of immersed tunnel engineering is feasible, and it can be popularized and applied in similar projects. [ABSTRACT FROM AUTHOR]

For complex attribute engineering based on attribute access control, this paper performed partial security expansion is based on the MPT ( Merkle Patricia tree) method of the data storage structure used at the bottom of Ethereum, modeled discrete attributes into a unified MPT attribute set, and then Merkle proof method ensured the integrity of the attribute set. In order to ensure that the attribute privacy will not be leaked and enhance the security of the MPT attribute system in a distributed environment, it used the elliptic curve encryption algorithm of the public key system to process the attribute value. In addition, this article stored the MPT attribute set in a database to implement dynamic attribute operations. Theoretical analysis and experimental results show that this strategy can solve the integrity and security problems of attribute engineering, and makes attribute-based access control easy to implement in a distributed environment. [ABSTRACT FROM AUTHOR]

During the construction of deep cement mixing（ DCM） vessel, the original soil is mainly mixed by rotating and cutting the mixing blades of the processor to ensure the pile quality. Due to the different structures of the mixing blades, it has a great impact on the work efficiency of the DCM pile, thus affecting the overall progress of the project. Taking the offshore DCM pile construction of Hong Kong Airport project as an example, this paper analyzes the working efficiency of the vessel under different mixing blade designs, so as to provide basic construction data reference for the implementation of engineering projects in the future. [ABSTRACT FROM AUTHOR]

The national concept of dietary nutrition and health has changed from“eating-full”, “eating-well” to “eating-right”, as China's per capita gross domestic product (GDP) in 2019 reached 10,000 U.S. dollars. Modern diets are gradually moving from basic requirement of nutrition and flavor, to three major elements including safety, nutrition and health. The paper put forward a new framework of the dialectical nutrition based on Chinese dietary therapy and modern nutrition. The dialectical nutrition, based on the “new nutrition science” that proposed by the 18th International congress of Nutrition, aims to explore food nutrition, human physique and their dialectical relationship, using a dialectical and systematic approach. According to the overall, comprehensive and balanced nutritional perspective, the framework was then combined with the diet and taste of food in Chinese dietary therapy, in order to build a whole discipline system from philosophy to science. The evaluation system can be suitable for the characteristics of Chinese diet, physical classification, and health status. The dialectical nutrition, served as a sort of nutrition discipline, is complied with the definition and concept of new modern nutrition, with emphasizing on the interdisciplinary integration in the range of biology, sociology, and humanities. The purpose of dialectical nutrition was used to balance the dynamic transformation of food and nutritional physique, in order to achieve human nutrition and health. This is because the dialectic method was a theoretical strategy with technical precision and dynamic balance. Therefore, this study proposed a construction of two framework for 1) the healthy food engineering system based on six attributes, including germplasm, habitat, processing, nutrition, function, and bias, and for 2) the nutrition physical engineering system based on six evaluated indices, including basal metabolism, gastrointestinal macrogenes, nutritional genes, emotional strength, immunity, digestion and absorption ability.A dynamic model of transformation balance has also established based on the big data mining. The integrated frameworks with the dynamic models can form an new engineering system for nutrition and health. This proposed system can provide sound basis for the four supporting systems of talents, technology, industry and capital in China society. The study can innovate the development of the healthy food industry, and upgrade of national healthy consumption, as well provide scientific dietary guidance for the health of the entire population, and lay a solid healthy foundation for the national effort to build China into a comprehensive moderately prosperous society. [ABSTRACT FROM AUTHOR]

Progress and development of Chinese agricultural modernization are accompanied by the rapid changing of the society. Agricultural infrastructure, one of the core factors, has the characteristics of complexity, dynamism and openness. Construction quality and comprehensive benefit need modern engineering theory and methods to support the whole process of agricultural modernization. Taking productive hardware infrastructure as research objects, this paper studied and analyzed the concept, connotation, characteristics, content and current situation of agricultural infrastructure. And the concept, characteristics, content, mutual relation and development trend of agricultural infrastructure engineering were proposed. This paper pointed out that agricultural infrastructure mainly refers to the basic hardware facilities to improve the operating ability of agricultural production and represents the pilot factor of agricultural and rural development, and it is the premise of strengthening the foundation of agriculture, and the key to improve the competitiveness of agriculture. And the quality and long term are the important elements of the construction of the infrastructure in the future. Agricultural infrastructure should include roads, water conservancy, telecommunications, electricity, energy, farmland construction, horticulture, animal husbandry, aquatic facilities, storage, processing, environmental protection, services, emergency, construction, and so on. Agricultural infrastructure engineering means the procedure, making the quality and function of the whole life cycle of infrastructure fully guaranteed based on the theories and achievements of science and technology under the scientific operation mechanism and standard specification implemented by the organization. And the agricultural infrastructure engineering has the characteristics of scientific nature, systematicness, standardization, high efficiency and persistence. Agricultural infrastructure engineering is composed of project strategy, engineering decision-making, engineering preparation, engineering implementation and the various stages of the project operation and the closed loop of the 4 factors. Agricultural infrastructure engineering mainly experiences 3 stages. In the early stage of engineering development, agricultural infrastructure engineering has the trend of piloting the content system and meets the sustainable development requirements. The results showed that agricultural infrastructure engineering means the applications of the concept, methods, techniques and the results of the project in the construction of agricultural engineering. And the agricultural infrastructure engineering was promoted from microcosmic and macroscopic aspects. At the microscopic aspect, the tools and methods of the engineering strategy, engineering decision, project preparation, project implementation and project operation are considered throughout the whole process of the life cycle of the agricultural basic construction project. At the macroscopic aspect, it needs to link the comprehensive decision of various constructions, implementations and evaluations, and systematize and optimize the advancement of the timing, extent, goals, and so on. These practices can maximize the long-term stability of agricultural infrastructure in Chinese agricultural modernization. In the circumstance of accelerating China's agricultural modernization, the contents of agricultural infrastructure engineering need to be enriched and improved, and the views, methods, and tools revealed in this study can provide the basis for advancing this process. [ABSTRACT FROM AUTHOR]

Based on the statistical analysis of the historical operation data and the simulation results of the steady-state model, the analysis of the purification equipment and the public system was carried out to analyze the low-load operation conditions of the high-sulfur natural gas purification plant in this paper. In the process, the relationship between the energy consumption and the running load was clarified. Then, the advanced method of energy saving in the internal structure of the natural gas purification plant was put forward based on the optimization of the load distribution with the lowest unit cost. Further, the whole plant production self-use gas and the power consumption were studied with the change of the load. Energy-matching relationship of main devices with common system was determined. Meanwhile, the advanced practice of saving the common system was proposed, as well as the guiding opinions for the low-load energy-saving operation of the domestic high-sulfur natural gas purification plant. [ABSTRACT FROM AUTHOR]

It is required the favorable controlled flight performance in full speed bound and wide flight airspace, wide range of mobility and horizontal landing capability for suborbital reusable launch vehicle (SR-LV), which involve many field of aerodynamic problem: the subsonic, transionic, supersonic, hypersonic and rarefied field. Therefore the advanced aerodynamic configure design technology is one of the key technology for develop of SRLV. In this paper, engineering optimization method with Kriging response surface method is adopted to optimization flight aerodynamic characteristic with the engineering restriction for SR-LV, the aerodynamic configure satisfied with the requirement is found. New method may be used to engineering design, and enhance the work efficiency. [ABSTRACT FROM AUTHOR]

In line with the fact that major inspections and minor inspections are usually adopted together for system inspection in engineering practice, this paper proposes a multiple inspection policy model based on a three-stage failure process. The concept of the three-stage failure process divides the system lifetime into three stages, that is, normal stage, minor defective stage and severe defective stage. With the consideration of all the possible scenarios for failure renewal, minor inspection renewal and major inspection renewal, a multiple inspection policy model is presented for single-unit systems using the renewal reward theory. The objective of the model is to minimize the long-run expected cost per unit time, with the minor and major inspection intervals as the decision variables. In order to illustrate the applicability of the multiple inspection policy, a single inspection policy counterpart which includes only major inspections is also developed for the purpose of comparison. The threshold value for the minor inspection cost which makes the multiple inspection more favorable than the single inspection policy is studied. Numerical examples are presented and the results show that the multiple inspection policy is better than the single inspection policy when the cost of minor inspection is smaller than the threshold level and other parameters are fixed. [ABSTRACT FROM AUTHOR]

In a surrounding expected by the high safety, the critical operation errors could lead to a disaster, therefore, to assess human reliability for critical operator not only provides support for the estimate of the disaster of systems but also is useful to improve the level of training and the condition of the critical operators. In this paper, human reliability is researched by studying the decomposition and composition of factors, compensatory and irreplaceable factors are defined, and the method of composition of states of compensatory and irreplaceable factors (CSICF) is then established. For the characteristic of the basic flow of spacecraft launch engineering, the factors of space and the features of the human reliability of a spacecraft launch are analyzed and the overall human reliability model of spacecraft launch is constructed. Finally, a case analysis demonstrates the application of the human reliability assessment model of a spacecraft launch engineering, which validates the feasibility of the human reliability analysis method of CSICF. [ABSTRACT FROM AUTHOR]

Based on the three positioning principles for installation in bridge engineering, the fourth positioning principle for installation which is suitable for the construction engineering is put forward. Based on the characteristics and applicability of a few existing analysis methods of construction mechanics for structure and according to the positioning principles of components of structure in actual projects, an improved nonlinear analysis method named element birth and death of local configuration constraint is put forward to solve the problem of death element's 'floating' in this paper. This method was applied in the mechanical emulation and analysis of the Heshi Stupa of Famen Temple during the construction process. The computation results by the improved method agreed with the measured values well in the project. This indicates that the improved method is an effective analysis method of construction mechanics for structure. [ABSTRACT FROM AUTHOR]

Based on depth study of the influence law of key strata on the height of fractured water-conducting zone, this paper proposed a new method to predict the height of fractured water-conducting zone by location of key strata. The engineering measurements and theoretical research results show that the key stratum location affects the height of fractured water-conducting zone in the roof, when the distance from key stratum to the coal seam is less than a critical value, the fracture of key stratum will develop to water-conducting fracture, and the same goes to the fracture of the overlying strata controlled by key stratum leading to a synchronous breakage with key stratum. The critical height of key stratum fracture can be roughly estimated to be (7 ~ 10) M, where M is coal mining height. When it is less than (7 ~ 10) M from the primary key stratum to coal seam, water-conducting fracture will grow to the location above the roof of the bed rock, then the height of fractured water-conducting zone is equal to or greater than the height of the bed rock. When the distance from the primary key stratum to coal seam is greater than (7 ~10) M, water-conducting fracture in the roof will develop to the position below the nearest key stratum being (7 ~ 10) M more away from the coal seam ,and then the height of fractured water-conducting zone equals to the distance of the key stratum to coal seam. The prediction method is able to predict the height of fractured water-conducting zone in the roof with different mining heights, meanwhile, it also can be utilized to distinguish the abnormal development of the height of fractured water-conducting zone induced by structural changes of key stratum, and its reliability is verified by engineering measurements results. [ABSTRACT FROM AUTHOR]

In the introduction of the full paper, we point that, in our opinion, Cuckborn and Shu's Runge Kutta discontinuous Galerkin method is good in calculation precision, but its slow convergence puts severe limits on its application to engineering problems. Therefore, we propose our efficient implicit scheme for accelerating convergence. In the iterative process, some important amendments are in application, which improve the efficiency significantly. At the same time, LU-SGS method is used to solve the large sparse linear system. By this means, subsonic and transonic flow over the airfoil is computed. It is found that this implicit scheme keeps unconditional stable for the subsonic and transonic flow. These results show preliminarily that, compared with the explicit scheme, our novel solver delivers a convergence rate that is approximately one order higher and much of the CPU time is saved. [ABSTRACT FROM AUTHOR]

Analysis and forecasting were made in this paper aiming at the problem of top pressure of coke tower of 1200 x 10³ t/a delayed coking unit in the refinery of Daqing Petrochemical Company rises continuously causing by volaile lines coking. Various operation conditions of the unit are alibrated, the results show that the higher the furnace outet temperature, the smaller processing capacity of the unit, After taking a series of measures such as stopping blending with FCC slurry oil, injecting defoamer and so on, the height of foam layer in coke tower was decreased so as to low down the coking rate of the volatile lines, which provides a strong guarantee for long-term operation of the unit. [ABSTRACT FROM AUTHOR]

Safety Integrity Level (SIL) assessment basis, function, method and application cases are introduced in this paper. According to the different needs of newly built and constructed projects, different purposes and functions of SIL assessment are described. Then, necessity of SIL assessment is put forward combining with the engineering practice, and the rationality and effectiveness of constructing SIS are expounded referencing to related standards. The next, the basic application method of SIL assessment is discussed with practical engineering cases. At last, the application trend of SIL evaluation is expounded. [ABSTRACT FROM AUTHOR]

This paper took Haishiwan coalfield as the background and CO2 in the No. 2 coal seam of Haishiwan mine area as the main study object, systematically carrying out study of various aspects on the causes of CO2, CO2 enrichment regularity, CO2 occurrence in coal seam of Yaojie coalfield, adsorption and desorption of CO2 in coal, numerical simulation and engineering practice applied to eliminate the risk of coal and CO2 outburst regionally, making some innovations. During the researches, the authors adopted all kinds of research methods that multi-disciplinary theory includes geochemistry, petrology, structural geology, surface chemistry, rock mechanics, mining engineering, mechanics, numerical simulation, theoretical analysis, laboratory experiments and field engineering practice. The main research content and conclusions are as follows: (1) The CO2 concentration range in the eastern coalfield is 18.79% to 96.6%. The δ13Cco2 values are mainly in the range of -5.0‰ to + 1.0‰ ( PDB ), suggesting an inorganic origin of CO2. The ³He/4 He ratios are (0.6 ~ 25.9) x 108, and the R/Ra is 0. 004 2 ~ 0. 185 0, which is a characteristic of crust-derived CO2 gas. The dynamic-thermal metamorphism of the F19 ductile-brittle shear zone is believed to result in the release of CO2 from basement marble formations, which shows an inorganic source of CO2 in the Haishiwan coalfield. The regional geological evolution and multi-periodical F19 fault movement control the formation, migration, and accumulation of CO2. The F19 fault plays multiple roles in the generation, transport, and sequestration of gas during the CO2 formation. (2) The studies on the characteristics of coal absorbing CO2 or CO2 and CH4 mixed gas are carried out under low pressure. The D-A model can fit the adsorption isotherms of CO2 well under low pressure. At the same time, the authors establish the modified D-A, which fit the present high-pressure adsorption data well. The modified model is applied to analyze the supercritical CO2 adsorption isotherms of Haishiwan coal field and abnormal adsorption isotherms introducing free volume theory of polymer. The result is preliminarily verified by desorption curve. (3) The mining depth of the Haishiwan mine coal is 600 to 1 000 m, where the coal reservoir temperature is in the range of 31.72 to 43.88 °C. The measured mixture gas pressure is not less than 7.3 MPa;the CO2 concentration range in the eastern coalfield exceeded 90%; statistical gas content is in the range of 50 to 60 m³/t. Supercritical CO2 is likely to exist in the No. 2 coal seam of the Haishiwan coalfield according to in situ measurement, experimental determination and theoretical analysis. (4) The numerical simulation results indicate that the range of pressure-relief and dilatational strain of lower coal-rock mass increases along with the pore pressure increases, the maximum absolute and the maximum relative amount of deformity reach 328 mm and 0.5 % under pore pressure of 9 MPa respectively. At the same time, the plastic area also increases along with pore pressure enlargement. It is indicated that the pore pressure plays strengthen role in the protected coal seam pressure relief according to plate theory. (5) High pore pressure acts on pressure relief of coal seam, which has been verified in practice of remote protective coal seam mining and pressure-relief gas drainage. The singe gas drainage flow reaches more than 2 m³/min. The coal seam permeability increases by 878 times. The gas content decreases from 53 m³/t to 12 m³/t. The risk of outburst has been eliminated with regard to the No. 2 coal seam. [ABSTRACT FROM AUTHOR]