The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deep...The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of China and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:1.the type of quality information;2.the content of quality information;3.the construction of the se nsitive web for transfering information, and collecting and transfering quality information rapidly and effectively;4.the way and procedure to transfer informa tion;5.the construction of quality information library for all phases; 6.the d isposal of quality information;7.the decision making support system of the mana gement of quality information;8.attach importance to three key factors on impro ving quality concept.展开更多
In China with the implement of the strategy of overall opening up to the outside world,northeast China has basically formed an open pattern with simultineous development of border opening and coast opening. As a natio...In China with the implement of the strategy of overall opening up to the outside world,northeast China has basically formed an open pattern with simultineous development of border opening and coast opening. As a national window to open up to the outside world, an open port system in northeast region has formed. These ports can be classified from different angles, such as management level, transport mode, location. From management level, they can be classified into the state firstclass ports and the second-class ports. According to transpost mode, they can be divided into railway port, highway port, water transport port, air transport port and special mode port, and based on location, they can be divided into border port, coast port and inland port. The oaper introduces in detail the foreign trade connection of 4 most representative state first-class border ports: Hunchun, Suifenhe, Heihe and Manzhouli. The open ports Of northeast coast regin mean mainly coast water transport ports in Liaodong Peninsula. The foreign trade connection of coast open ports: Dandong, Jinzhou,Yingkou and Dalian is expounded. And the paper also analyses the transport connection of ports of northeast region with their hinterlands.展开更多
Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics activities.The most efficient way of doing so is through intermodal transportati...Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics activities.The most efficient way of doing so is through intermodal transportation(IT).Current IT systems rely mostly on road,rail,and sea transport,not inland waterway transport.Developing dry port(DP)terminals has been proven as a sustainable means of promoting and utilizing IT in the hinterland of seaport container terminals.Conventional DP systems consolidate container flows from/to seaports and integrate road and rail transportation modes in the hinterland which improves the sustainability of the whole logistics system.In this article,to extend literature on the sustainable development of different categories of IT terminals,especially DPs,and their varying roles,we examine the possibility of developing DP terminals within the framework of inland waterway container terminals(IWCTs).Establishing combined road–rail–inland waterway transport for observed container flows is expected to make the IT systems sustainable.As such,this article is the first to address the modelling of such DP systems.After mathematically formulating the problem of modelling DP systems,which entailed determining the number and location of DP terminals for IWCTs,their capacity,and their allocation of container flows,we solved the problem with a hybrid metaheuristic model based on the Bee Colony Optimisation(BCO)algorithmand themeasurement of alternatives and ranking according to compromise solution(i.e.,MARCOS)multi-criteria decision-making method.The results from our case study of the Danube region suggest that planning and developingDP terminals in the framework of IWCTs can indeed be sustainable,as well as contribute to the development of logistics networks,the regionalisation of river ports,and the geographic expansion of their hinterlands.Thus,the main contributions of this article are in proposing a novel DP concept variant,mathematically formulating the problems of its modelling,and developing an encompassing hybrid metaheuristic approach for treating the complex nature of the problem adequately.展开更多
With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,le...With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,legal supervision,and other aspects,this paper takes Hainan Free Trade Port as an example to analyze and study its institutional integration strategy for creating a world-class facilitating business environment.The specific integration strategies are summarized to promote the internationalization and facilitation of the business environment of Hainan Free Trade Port and promote the high development of the local economy.展开更多
Information theoretical results have shown that Distributed Antenna Systems (DAS) can obtain higher capacity than Co-located Antenna Systems (CAS). In this paper,we investigate a downlink port selection and power allo...Information theoretical results have shown that Distributed Antenna Systems (DAS) can obtain higher capacity than Co-located Antenna Systems (CAS). In this paper,we investigate a downlink port selection and power allocation scheme in Distributed Multiple-Input Multiple-Output (D-MIMO) systems,where Distributed Antenna (DA) ports randomly locate in the cell. The contri-bution of this paper can be summarized as two parts. Firstly,we analyze how antenna correlation af-fects power allocation in D-MIMO systems. Secondly,based on large scale fading and antenna corre-lation,a low-complexity port selection and power allocation scheme is proposed. In the proposed scheme,we take both large scale fading and antenna correlation into consideration. Moreover,User Equipment (UE) only needs to feedback the rank of transmit antenna correlation matrix,which will not increase system complexity too much. Simulation results verify the capacity improvement based on the proposed power allocation scheme.展开更多
Many ocean transportation hub systems consist of two container ports that share the container handling business in the area. The container flow passing through a port is the main measurement of the port＇s competitive...Many ocean transportation hub systems consist of two container ports that share the container handling business in the area. The container flow passing through a port is the main measurement of the port＇s competitiveness. In this paper we adopt a Hotelling model to study the container port competition in a so-called ＂dual gateway-port system＂. The system contains two ports and two terminals, one belonging to each port. The two governments in which the two ports are located compete on cargo fees and the two terminals determine service price and service quality. We study two models with different levels of competition between the terminals. In the ftrst model, the two terminals are owned by two different operators and in the second model, the two terminals are centralized under one operator. The second model exists in practice but is not well studied in the literature. We derive the cargo fee, terminal service price, and service quality equilibria for these two models. We investigate the competition outcome sensitivity with a numerical study. The numerical results reveal that governments prefer terminals to compete with each other. If the terminals do not have competitive advantages in their service quality, then terminal centralization brings more profits to the terminal operator than the competition case.展开更多
Expert system plays an important role in port machine diagnosis, which aims at automatic equipment test for higher availability and efficiency of port operations. In this study, a port machine diagnosis expert system ...Expert system plays an important role in port machine diagnosis, which aims at automatic equipment test for higher availability and efficiency of port operations. In this study, a port machine diagnosis expert system is proposed based on multi-reasoning mechanism. Relying on the knowledge acquired from the experienced experts in the port machine engineering, the system builds a library of relative experience and a set of rules of reasoning and estimating. Multi-reasoning mechanism that simulates the decision-making process of domain experts is employed to achieve reliable diagnosis results. The reasoning machine integrates artificial neural network, uncertain decision making and decision tree, which complements each other by sustainable growing voting mechanism. The effect of this multi-reasoning mechanism is evaluated and validated by means of Matthew＇s Correlation Coefficient （MCC）. The system incorporating the mechanism is successfully designed, implemented and applied in Shanghai Port.展开更多
In this paper we apply networks of queues in the design and analysis of aseaport system. There are two types of ports, the deep water port and shallow waterport. The steamships arrive via the Pacific ocean according t...In this paper we apply networks of queues in the design and analysis of aseaport system. There are two types of ports, the deep water port and shallow waterport. The steamships arrive via the Pacific ocean according to a random process, andcan only enter the deep water port (due to the size of the ships). The finite capacityof the port, often results in long delays which is undsirable. To reduce this congestionproblem, ports authorities are considering constructing a platform (or dock) in a deepwater area on which some steamships can be first downloaded, and then the goods onthe platform are delivered and downloaded on the shallow water port by many small-sizeboats. This sytstem is modeled as a network of queues with finite buffers and blocking.We develop approximation methodology for analyzing queue delays, and apply it, in thedesign and optimization of the port systems. The algorithm is proved to be efficient, andits effectiveness is shown by both numerical results and simulation analysis.展开更多
The analysis and evaluation of an actual port system containing R differentship’s kinds and N subsystems each of which consists of M.(i=1, 2,…, N) ports arederived. The external arrivals of ships to the system come ...The analysis and evaluation of an actual port system containing R differentship’s kinds and N subsystems each of which consists of M.(i=1, 2,…, N) ports arederived. The external arrivals of ships to the system come from R different Poisson sourcesand the interarrivals to the queue of each port of a subsystem are determined according tocondition probabilities. Each port has multiple berths whose service times are distributedaccording to Erlang probability distribution functions. Each port of a subsystem has Rinfinite capacity buffers for storing ships interarrived. This method provides a good approximation procedure for obtaining system perfor-mance measures such as waiting times of ships, average queue lengths, etc. Optimum portcapacity can thus be evaluated by using this analysis. A simulation is also presented totest this approximate analysis, and a good agreement is observed. This model shall be usedin the planning of several actual port systems. Through the application of this model, itis possible to analyze and evaluate performances of the systems.展开更多
After the Tianjin Port 8.12 explosion, an enormous amount of potassium dichromate （K2Cr2O7） and butanone （CH3COCH2CH3） leaked into the coastal soil-groundwater system, which potentially threatened the environment ...After the Tianjin Port 8.12 explosion, an enormous amount of potassium dichromate （K2Cr2O7） and butanone （CH3COCH2CH3） leaked into the coastal soil-groundwater system, which potentially threatened the environment and human health. Determining the transport process of hazards is necessary to establish guidelines for remediating the contaminated area. This work aims to investigate the migration of potassium dichromate and butanone in the coastal soil-groundwater system through a coupling unsaturated-saturated numerical model, incorporating the HYDRUS model into the MODFLOW/ MT3D model. In the unsaturated zone, two-dimensional HYDRUS model was applied, and its recharge flux at the bottom boundary was utilized as the input of MODFLOW/MT3D model in the saturated zone. Results showed that Cr2O^（2-）7 migrated much faster than butanone in the unsaturated zone and reached the water table in about 1 year. In comparison, butanone was unlikely to enter the aquifer even 5 years later with a migration depth of about 2.2 m. Driven by groundwater, the Cr2O^（2-）7 that entered the aquifer migrated about 161 m toward southeast 5 years later. In the saturated zone, the contamination plume covered mainly the southeast area due to the groundwater flow direction.展开更多
Background: Studies have suggested epidemiological transition in the mortality pattern in Nigeria from communicable to non-communicable diseases of which Diseases of the cardiovascular system (DCVS) is prime. DCVS is?...Background: Studies have suggested epidemiological transition in the mortality pattern in Nigeria from communicable to non-communicable diseases of which Diseases of the cardiovascular system (DCVS) is prime. DCVS is?thus a growing public health concern but its mortality profile is under-studied?in Port Harcourt. This study was therefore designed to review the mortality profile of DCVS in Port Harcourt. Methodology: A retrospective case controlled study of deaths ascribed to DCVS at the University of Port Harcourt Teaching Hospital (UPTH) between January 2012 and December 2017. The composite diseases were grouped using the ICD10 scheme and analyzed using SPSS version 23. Minitab version 16 was used for trend analysis. Results: Of the overall 1902 deaths recorded within the period, 566 (29.8%) were cardiovascular system related. Of these, 301 (53.3%) were males and 265 (46.7%) were females. The elderly of 50 - 99 years were most commonly affected (65.5% of the mortalities). Cerebrovascular accidents (CVA) accounted for 322 deaths (56.9%);various types of shock caused 116 deaths (20.5%) while?congestive cardiac failure (CCF) accounted for 114 deaths (20.1%). Pulmonary?embolism, myocardial infarction, carotid aneurysm, and hypertensive encephalopathy caused 1.8%, 0.4%, 0.2%, and 0.2% deaths respectively. Peak annual mortality of 143 (25.3%) was recorded in 2013. Although the trend of mortality was undulating, there was an overall increase in annual incidence over the years.?Conclusion: DCVS constitute the commonest systemic cause?of death in Port Harcourt. Governmental and donor agencies involved in public health policy planning and implementation should scale-up strategies for the prevention and control of DCVS in order to stem the rising tide of associated mortalities.展开更多
This paper proposes the design scheme of Integration Management and Control System (IMCS) using the integration and optimization design theory of port cranes’ management and control system based on Enterprise Resourc...This paper proposes the design scheme of Integration Management and Control System (IMCS) using the integration and optimization design theory of port cranes’ management and control system based on Enterprise Resource Planning (ERP), Manufacturing Execution System (MES) and Process Control System (PCS). The functions, interface and software design of the three sub-modules of IMCS are presented. Outcomes of this research are being employed to practical port cranes’ operation and management, which eliminates the island phenomenon of cranes’ storage and application conditions between the management and control department. Hence, IMCS makes the integrated automatic port cranes system come true and it significantly improves the core competitiveness of the port.展开更多
Objective: to explore the application effect of continuous nursing system in the nursing of discharged patients in intravenous infusion port. Methods: from February 2019 to January 2021, 82 patients with implantable i...Objective: to explore the application effect of continuous nursing system in the nursing of discharged patients in intravenous infusion port. Methods: from February 2019 to January 2021, 82 patients with implantable intravenous infusion port were treated in our hospital. According to the parity of admission number, 41 odd cases entered the control group for routine discharge follow-up nursing;An even number of 41 patients entered the experimental group and adopted the continuous nursing system. The maintenance compliance, self-care ability and quality of life of infusion port were compared. Results: the excellent and good rate of maintenance compliance of infusion port in the experimental group was higher than that in the control group (97.56% vs 82.93%);After the intervention, the scores of ESCA and QOL in the experimental group were significantly higher than those in the control group. The test results showed that there was significant difference (P < 0.05). Conclusion: the continuous nursing system for discharged patients in intravenous infusion port can not only improve the maintenance compliance of infusion port, but also improve their self-care ability and quality of life, so it is worth popularizing.展开更多
China has a large population,a large middle-income group,and a wide consumer market coverage.In the context of economic globalization,the connection between the Chinese economy and the world industrial chain has been ...China has a large population,a large middle-income group,and a wide consumer market coverage.In the context of economic globalization,the connection between the Chinese economy and the world industrial chain has been further strengthened,contributing to the development of the global economy.Under the background of the Hainan Free Trade Port,building an economic service trade system will help to create a new highland for economic service trade,promote the development of China’s service trade,and facilitate the rational allocation of resources on a global scale.Because of this,the article will analyze the opportunities for building an economic service trade system and the challenges of building an economic service trade system under the background of Hainan Free Trade Port,and focus on analyzing the path strategies for building an economic service trade system to create a high-level new highland of service trade and actively face the challenges of era development and economic upgrading[1].展开更多
We consider the design of structure-preserving discretization methods for the solution of systems of boundary controlled Partial Differential Equations (PDEs) thanks to the port-Hamiltonian formalism. We first provide...We consider the design of structure-preserving discretization methods for the solution of systems of boundary controlled Partial Differential Equations (PDEs) thanks to the port-Hamiltonian formalism. We first provide a novel general structure of infinite-dimensional port-Hamiltonian systems (pHs) for which the Partitioned Finite Element Method (PFEM) straightforwardly applies. The proposed strategy is applied to abstract multidimensional linear hyperbolic and parabolic systems of PDEs. Then we show that instructional model problems based on the wave equation, Mindlin equation and heat equation fit within this unified framework. Secondly, we introduce the ongoing project SCRIMP (Simulation and Control of Interactions in Multi-Physics) developed for the numerical simulation of infinite-dimensional pHs. SCRIMP notably relies on the FEniCS open-source computing platform for the finite element spatial discretization. Finally, we illustrate how to solve the considered model problems within this framework by carefully explaining the methodology. As additional support, companion interactive Jupyter notebooks are available.展开更多
Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,...Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,ISO established ISO/TC 8/SC 27,Ports and terminals,the secretariat of which is held by China.This is a big breakthrough of China’s participation in the international standardization activities in the area of transportation.展开更多
Ghana’s Tema Port marked a historic milestone on 16 January 2024 with the arrival of Maersk Edirne,a 13,676-TEU container vessel-one of the largest of its kind globally-as part of Maersk’s newly launched Far East-We...Ghana’s Tema Port marked a historic milestone on 16 January 2024 with the arrival of Maersk Edirne,a 13,676-TEU container vessel-one of the largest of its kind globally-as part of Maersk’s newly launched Far East-West Africa express service.展开更多
BACKGROUND Arm-implanted totally implantable venous access devices(peripherally inserted central catheter port)have become an important vascular access for colorectal cancer chemotherapy,but traditional anatomical lan...BACKGROUND Arm-implanted totally implantable venous access devices(peripherally inserted central catheter port)have become an important vascular access for colorectal cancer chemotherapy,but traditional anatomical landmark positioning techniques have issues with inaccurate positioning and high complication rates.AIM To evaluate the clinical value of image pre-measurement combined with intracavitary electrocardiogram(IC-ECG)positioning technology in arm port implantation for colorectal cancer patients.METHODS A retrospective analysis was conducted on 216 colorectal cancer patients who received arm port implantation in our hospital from January 2024 to December 2024.Patients were divided into an experimental group(image pre-measurement combined with IC-ECG positioning technology,n=103)and a control group(traditional anatomical landmark positioning technique,n=113).Technical success rate,operation time,catheter tip position accuracy,number of intraoperative catheter adjustments,X-ray exposure time,and postoperative complication rates were compared between the two groups.RESULTS The experimental group demonstrated superior outcomes compared to the control group across all key measures.Technical success rate was higher(98.4%vs 92.7%,P<0.05)with significantly reduced operation time(23.6±5.2 minutes vs 31.5±7.8 minutes,P<0.01).Catheter tip positioning accuracy improved substantially(97.6%vs 85.4%,P=0.002)while X-ray exposure time decreased by 71.8%(5.3±2.1 seconds vs 18.7±4.5 seconds,P<0.001).Threemonth complication rates were markedly lower in the experimental group(4.1%vs 14.6%,P=0.008),including significant reductions in catheter-related thrombosis(0.8%vs 4.9%),displacement(1.6%vs 5.7%),and occlusion(1.6%vs 4.1%).Multivariate analysis identified traditional technique as the strongest risk factor(odds ratio=4.27,P<0.001),while the combined IC-ECG approach was protective(odds ratio=0.34 for displacement,P=0.018).Long-term outcomes favored the experimental group with higher chemotherapy completion rates(97.1%vs 88.5%,P=0.014)and longer catheter dwelling time(189.5±45.3 days vs 162.7±53.8 days,P<0.001).CONCLUSION Image pre-measurement combined with intracavitary electrocardiogram positioning technology in arm port implantation for colorectal cancer patients can significantly improve catheter tip positioning accuracy,reduce operation time and X-ray exposure.展开更多
文摘The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of China and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:1.the type of quality information;2.the content of quality information;3.the construction of the se nsitive web for transfering information, and collecting and transfering quality information rapidly and effectively;4.the way and procedure to transfer informa tion;5.the construction of quality information library for all phases; 6.the d isposal of quality information;7.the decision making support system of the mana gement of quality information;8.attach importance to three key factors on impro ving quality concept.
文摘In China with the implement of the strategy of overall opening up to the outside world,northeast China has basically formed an open pattern with simultineous development of border opening and coast opening. As a national window to open up to the outside world, an open port system in northeast region has formed. These ports can be classified from different angles, such as management level, transport mode, location. From management level, they can be classified into the state firstclass ports and the second-class ports. According to transpost mode, they can be divided into railway port, highway port, water transport port, air transport port and special mode port, and based on location, they can be divided into border port, coast port and inland port. The oaper introduces in detail the foreign trade connection of 4 most representative state first-class border ports: Hunchun, Suifenhe, Heihe and Manzhouli. The open ports Of northeast coast regin mean mainly coast water transport ports in Liaodong Peninsula. The foreign trade connection of coast open ports: Dandong, Jinzhou,Yingkou and Dalian is expounded. And the paper also analyses the transport connection of ports of northeast region with their hinterlands.
文摘Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics activities.The most efficient way of doing so is through intermodal transportation(IT).Current IT systems rely mostly on road,rail,and sea transport,not inland waterway transport.Developing dry port(DP)terminals has been proven as a sustainable means of promoting and utilizing IT in the hinterland of seaport container terminals.Conventional DP systems consolidate container flows from/to seaports and integrate road and rail transportation modes in the hinterland which improves the sustainability of the whole logistics system.In this article,to extend literature on the sustainable development of different categories of IT terminals,especially DPs,and their varying roles,we examine the possibility of developing DP terminals within the framework of inland waterway container terminals(IWCTs).Establishing combined road–rail–inland waterway transport for observed container flows is expected to make the IT systems sustainable.As such,this article is the first to address the modelling of such DP systems.After mathematically formulating the problem of modelling DP systems,which entailed determining the number and location of DP terminals for IWCTs,their capacity,and their allocation of container flows,we solved the problem with a hybrid metaheuristic model based on the Bee Colony Optimisation(BCO)algorithmand themeasurement of alternatives and ranking according to compromise solution(i.e.,MARCOS)multi-criteria decision-making method.The results from our case study of the Danube region suggest that planning and developingDP terminals in the framework of IWCTs can indeed be sustainable,as well as contribute to the development of logistics networks,the regionalisation of river ports,and the geographic expansion of their hinterlands.Thus,the main contributions of this article are in proposing a novel DP concept variant,mathematically formulating the problems of its modelling,and developing an encompassing hybrid metaheuristic approach for treating the complex nature of the problem adequately.
基金General Scientific Research Project of Hainan Vocational University of Science and Technology-—Exploration of the Impact of Financial Reform on Enterprises in Hainan Free Trade Port(HKKY2024-13)。
文摘With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,legal supervision,and other aspects,this paper takes Hainan Free Trade Port as an example to analyze and study its institutional integration strategy for creating a world-class facilitating business environment.The specific integration strategies are summarized to promote the internationalization and facilitation of the business environment of Hainan Free Trade Port and promote the high development of the local economy.
基金Supported by the National High Technology Research and Development Program of China (863 Program,No.2006AA01Z272 and No.2006AA01Z283)Beijing Municipal Science & Technology Commission (No.D08080100620802)
文摘Information theoretical results have shown that Distributed Antenna Systems (DAS) can obtain higher capacity than Co-located Antenna Systems (CAS). In this paper,we investigate a downlink port selection and power allocation scheme in Distributed Multiple-Input Multiple-Output (D-MIMO) systems,where Distributed Antenna (DA) ports randomly locate in the cell. The contri-bution of this paper can be summarized as two parts. Firstly,we analyze how antenna correlation af-fects power allocation in D-MIMO systems. Secondly,based on large scale fading and antenna corre-lation,a low-complexity port selection and power allocation scheme is proposed. In the proposed scheme,we take both large scale fading and antenna correlation into consideration. Moreover,User Equipment (UE) only needs to feedback the rank of transmit antenna correlation matrix,which will not increase system complexity too much. Simulation results verify the capacity improvement based on the proposed power allocation scheme.
基金The authors appreciate the anonymous referees and the editor for their help to improve the quality of the paper. This paper was partially supported by the National Natural Science Foundation of China, NSFC Nos. 71001073, 71302109, 71471118, the Humanities and Social Sciences Foundation of Ministry of Education of China （No. 14YJC630096）, the Distinguished University Young Scholar Program of Guangdong Province （No. Yq2013140）, the Fundamental Research Funds for the Central Universities （No. 15JNQM028） and Natural Science Foundation of SZU （Grant Nos. 201422 and 827000074）.
文摘Many ocean transportation hub systems consist of two container ports that share the container handling business in the area. The container flow passing through a port is the main measurement of the port＇s competitiveness. In this paper we adopt a Hotelling model to study the container port competition in a so-called ＂dual gateway-port system＂. The system contains two ports and two terminals, one belonging to each port. The two governments in which the two ports are located compete on cargo fees and the two terminals determine service price and service quality. We study two models with different levels of competition between the terminals. In the ftrst model, the two terminals are owned by two different operators and in the second model, the two terminals are centralized under one operator. The second model exists in practice but is not well studied in the literature. We derive the cargo fee, terminal service price, and service quality equilibria for these two models. We investigate the competition outcome sensitivity with a numerical study. The numerical results reveal that governments prefer terminals to compete with each other. If the terminals do not have competitive advantages in their service quality, then terminal centralization brings more profits to the terminal operator than the competition case.
文摘Expert system plays an important role in port machine diagnosis, which aims at automatic equipment test for higher availability and efficiency of port operations. In this study, a port machine diagnosis expert system is proposed based on multi-reasoning mechanism. Relying on the knowledge acquired from the experienced experts in the port machine engineering, the system builds a library of relative experience and a set of rules of reasoning and estimating. Multi-reasoning mechanism that simulates the decision-making process of domain experts is employed to achieve reliable diagnosis results. The reasoning machine integrates artificial neural network, uncertain decision making and decision tree, which complements each other by sustainable growing voting mechanism. The effect of this multi-reasoning mechanism is evaluated and validated by means of Matthew＇s Correlation Coefficient （MCC）. The system incorporating the mechanism is successfully designed, implemented and applied in Shanghai Port.
文摘In this paper we apply networks of queues in the design and analysis of aseaport system. There are two types of ports, the deep water port and shallow waterport. The steamships arrive via the Pacific ocean according to a random process, andcan only enter the deep water port (due to the size of the ships). The finite capacityof the port, often results in long delays which is undsirable. To reduce this congestionproblem, ports authorities are considering constructing a platform (or dock) in a deepwater area on which some steamships can be first downloaded, and then the goods onthe platform are delivered and downloaded on the shallow water port by many small-sizeboats. This sytstem is modeled as a network of queues with finite buffers and blocking.We develop approximation methodology for analyzing queue delays, and apply it, in thedesign and optimization of the port systems. The algorithm is proved to be efficient, andits effectiveness is shown by both numerical results and simulation analysis.
文摘The analysis and evaluation of an actual port system containing R differentship’s kinds and N subsystems each of which consists of M.(i=1, 2,…, N) ports arederived. The external arrivals of ships to the system come from R different Poisson sourcesand the interarrivals to the queue of each port of a subsystem are determined according tocondition probabilities. Each port has multiple berths whose service times are distributedaccording to Erlang probability distribution functions. Each port of a subsystem has Rinfinite capacity buffers for storing ships interarrived. This method provides a good approximation procedure for obtaining system perfor-mance measures such as waiting times of ships, average queue lengths, etc. Optimum portcapacity can thus be evaluated by using this analysis. A simulation is also presented totest this approximate analysis, and a good agreement is observed. This model shall be usedin the planning of several actual port systems. Through the application of this model, itis possible to analyze and evaluate performances of the systems.
基金supported by the National Natural Science Foundation of China(No.21656001)
文摘After the Tianjin Port 8.12 explosion, an enormous amount of potassium dichromate （K2Cr2O7） and butanone （CH3COCH2CH3） leaked into the coastal soil-groundwater system, which potentially threatened the environment and human health. Determining the transport process of hazards is necessary to establish guidelines for remediating the contaminated area. This work aims to investigate the migration of potassium dichromate and butanone in the coastal soil-groundwater system through a coupling unsaturated-saturated numerical model, incorporating the HYDRUS model into the MODFLOW/ MT3D model. In the unsaturated zone, two-dimensional HYDRUS model was applied, and its recharge flux at the bottom boundary was utilized as the input of MODFLOW/MT3D model in the saturated zone. Results showed that Cr2O^（2-）7 migrated much faster than butanone in the unsaturated zone and reached the water table in about 1 year. In comparison, butanone was unlikely to enter the aquifer even 5 years later with a migration depth of about 2.2 m. Driven by groundwater, the Cr2O^（2-）7 that entered the aquifer migrated about 161 m toward southeast 5 years later. In the saturated zone, the contamination plume covered mainly the southeast area due to the groundwater flow direction.
文摘Background: Studies have suggested epidemiological transition in the mortality pattern in Nigeria from communicable to non-communicable diseases of which Diseases of the cardiovascular system (DCVS) is prime. DCVS is?thus a growing public health concern but its mortality profile is under-studied?in Port Harcourt. This study was therefore designed to review the mortality profile of DCVS in Port Harcourt. Methodology: A retrospective case controlled study of deaths ascribed to DCVS at the University of Port Harcourt Teaching Hospital (UPTH) between January 2012 and December 2017. The composite diseases were grouped using the ICD10 scheme and analyzed using SPSS version 23. Minitab version 16 was used for trend analysis. Results: Of the overall 1902 deaths recorded within the period, 566 (29.8%) were cardiovascular system related. Of these, 301 (53.3%) were males and 265 (46.7%) were females. The elderly of 50 - 99 years were most commonly affected (65.5% of the mortalities). Cerebrovascular accidents (CVA) accounted for 322 deaths (56.9%);various types of shock caused 116 deaths (20.5%) while?congestive cardiac failure (CCF) accounted for 114 deaths (20.1%). Pulmonary?embolism, myocardial infarction, carotid aneurysm, and hypertensive encephalopathy caused 1.8%, 0.4%, 0.2%, and 0.2% deaths respectively. Peak annual mortality of 143 (25.3%) was recorded in 2013. Although the trend of mortality was undulating, there was an overall increase in annual incidence over the years.?Conclusion: DCVS constitute the commonest systemic cause?of death in Port Harcourt. Governmental and donor agencies involved in public health policy planning and implementation should scale-up strategies for the prevention and control of DCVS in order to stem the rising tide of associated mortalities.
文摘This paper proposes the design scheme of Integration Management and Control System (IMCS) using the integration and optimization design theory of port cranes’ management and control system based on Enterprise Resource Planning (ERP), Manufacturing Execution System (MES) and Process Control System (PCS). The functions, interface and software design of the three sub-modules of IMCS are presented. Outcomes of this research are being employed to practical port cranes’ operation and management, which eliminates the island phenomenon of cranes’ storage and application conditions between the management and control department. Hence, IMCS makes the integrated automatic port cranes system come true and it significantly improves the core competitiveness of the port.
文摘Objective: to explore the application effect of continuous nursing system in the nursing of discharged patients in intravenous infusion port. Methods: from February 2019 to January 2021, 82 patients with implantable intravenous infusion port were treated in our hospital. According to the parity of admission number, 41 odd cases entered the control group for routine discharge follow-up nursing;An even number of 41 patients entered the experimental group and adopted the continuous nursing system. The maintenance compliance, self-care ability and quality of life of infusion port were compared. Results: the excellent and good rate of maintenance compliance of infusion port in the experimental group was higher than that in the control group (97.56% vs 82.93%);After the intervention, the scores of ESCA and QOL in the experimental group were significantly higher than those in the control group. The test results showed that there was significant difference (P < 0.05). Conclusion: the continuous nursing system for discharged patients in intravenous infusion port can not only improve the maintenance compliance of infusion port, but also improve their self-care ability and quality of life, so it is worth popularizing.
文摘China has a large population,a large middle-income group,and a wide consumer market coverage.In the context of economic globalization,the connection between the Chinese economy and the world industrial chain has been further strengthened,contributing to the development of the global economy.Under the background of the Hainan Free Trade Port,building an economic service trade system will help to create a new highland for economic service trade,promote the development of China’s service trade,and facilitate the rational allocation of resources on a global scale.Because of this,the article will analyze the opportunities for building an economic service trade system and the challenges of building an economic service trade system under the background of Hainan Free Trade Port,and focus on analyzing the path strategies for building an economic service trade system to create a high-level new highland of service trade and actively face the challenges of era development and economic upgrading[1].
文摘We consider the design of structure-preserving discretization methods for the solution of systems of boundary controlled Partial Differential Equations (PDEs) thanks to the port-Hamiltonian formalism. We first provide a novel general structure of infinite-dimensional port-Hamiltonian systems (pHs) for which the Partitioned Finite Element Method (PFEM) straightforwardly applies. The proposed strategy is applied to abstract multidimensional linear hyperbolic and parabolic systems of PDEs. Then we show that instructional model problems based on the wave equation, Mindlin equation and heat equation fit within this unified framework. Secondly, we introduce the ongoing project SCRIMP (Simulation and Control of Interactions in Multi-Physics) developed for the numerical simulation of infinite-dimensional pHs. SCRIMP notably relies on the FEniCS open-source computing platform for the finite element spatial discretization. Finally, we illustrate how to solve the considered model problems within this framework by carefully explaining the methodology. As additional support, companion interactive Jupyter notebooks are available.
文摘Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,ISO established ISO/TC 8/SC 27,Ports and terminals,the secretariat of which is held by China.This is a big breakthrough of China’s participation in the international standardization activities in the area of transportation.
文摘Ghana’s Tema Port marked a historic milestone on 16 January 2024 with the arrival of Maersk Edirne,a 13,676-TEU container vessel-one of the largest of its kind globally-as part of Maersk’s newly launched Far East-West Africa express service.
基金Supported by the Affiliated Hospital of Xuzhou Medical University,No.2024ZH04Xuzhou Municipal Science and Technology Bureau,No.KC23282.
文摘BACKGROUND Arm-implanted totally implantable venous access devices(peripherally inserted central catheter port)have become an important vascular access for colorectal cancer chemotherapy,but traditional anatomical landmark positioning techniques have issues with inaccurate positioning and high complication rates.AIM To evaluate the clinical value of image pre-measurement combined with intracavitary electrocardiogram(IC-ECG)positioning technology in arm port implantation for colorectal cancer patients.METHODS A retrospective analysis was conducted on 216 colorectal cancer patients who received arm port implantation in our hospital from January 2024 to December 2024.Patients were divided into an experimental group(image pre-measurement combined with IC-ECG positioning technology,n=103)and a control group(traditional anatomical landmark positioning technique,n=113).Technical success rate,operation time,catheter tip position accuracy,number of intraoperative catheter adjustments,X-ray exposure time,and postoperative complication rates were compared between the two groups.RESULTS The experimental group demonstrated superior outcomes compared to the control group across all key measures.Technical success rate was higher(98.4%vs 92.7%,P<0.05)with significantly reduced operation time(23.6±5.2 minutes vs 31.5±7.8 minutes,P<0.01).Catheter tip positioning accuracy improved substantially(97.6%vs 85.4%,P=0.002)while X-ray exposure time decreased by 71.8%(5.3±2.1 seconds vs 18.7±4.5 seconds,P<0.001).Threemonth complication rates were markedly lower in the experimental group(4.1%vs 14.6%,P=0.008),including significant reductions in catheter-related thrombosis(0.8%vs 4.9%),displacement(1.6%vs 5.7%),and occlusion(1.6%vs 4.1%).Multivariate analysis identified traditional technique as the strongest risk factor(odds ratio=4.27,P<0.001),while the combined IC-ECG approach was protective(odds ratio=0.34 for displacement,P=0.018).Long-term outcomes favored the experimental group with higher chemotherapy completion rates(97.1%vs 88.5%,P=0.014)and longer catheter dwelling time(189.5±45.3 days vs 162.7±53.8 days,P<0.001).CONCLUSION Image pre-measurement combined with intracavitary electrocardiogram positioning technology in arm port implantation for colorectal cancer patients can significantly improve catheter tip positioning accuracy,reduce operation time and X-ray exposure.
