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
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
BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly rare.Basilic vein variation usually presents without any clinical symptoms and is often regarded as a b...BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly rare.Basilic vein variation usually presents without any clinical symptoms and is often regarded as a benign alteration.This case was a patient with congenital basilic vein variation encountered during surgery for an infusion port.CASE SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port insertion.This peculiarity has hitherto remained undescribed in the literature.We offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its occurrence.We conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port implantations.CONCLUSION Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment.展开更多
In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecolo...In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area.展开更多
Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern Ch...Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern China from 2000 to 2018,this study explores the coupling coordination development of port and city environments and its impact on urban economic competitiveness by constructing the coupling coordination degree model and the panel threshold model.The research results show that:(1)In terms of the coupling coordination development of port and city environments,most coastal ports and their hinterland cities are in a state of moderate or serious disorder.Overall,the degree of coupling coordination of port and city environments needs to be further improved;(2)The coupling coordination degree of port and city environments has a significant impact on urban economic competitiveness,and this effect gradually increases with the development of the ports and the urban economy.Among the variables that impact the urban economic competitiveness,fixed assets investment and foreign trade are significant factors that can enhance urban economic competitiveness.(3)At present,there is a“U-shaped”relationship between the coupling coordination degree of port-city environments and the urban economic competitiveness.This relationship lies on the right side of the inflection point of the“U-shaped”curve.Therefore,following the concept of assigning priority to ecological development,expanding fixed assets investment and actively developing foreign trade can further enhance the urban economic competitiveness.展开更多
The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The pr...The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan.展开更多
In order to explore and foster innovation in international exchange and cooperation,this study focuses on the background of the construction of the Hainan Free Trade Port.It delves into the current development status,...In order to explore and foster innovation in international exchange and cooperation,this study focuses on the background of the construction of the Hainan Free Trade Port.It delves into the current development status,characteristic demands,and potential challenges of its international exchange and cooperation mechanisms.Through a comprehensive analysis of relevant cases,survey questionnaires,and literature,this study aims to provide feasible innovative models and recommendations to promote the sustained development of the Hainan Free Trade Port in the field of international exchange and cooperation,injecting new vitality into China’s economic globalization.This exploration contributes to a deeper understanding of the development of free trade ports and provides insights and references for other countries and regions.展开更多
AIM: To evaluate the feasibility of a second parallel transjugular intrahepatic portosystemic shunt(TIPS) to reduce portal venous pressure and control complications of portal hypertension.METHODS: From January 2011 to...AIM: To evaluate the feasibility of a second parallel transjugular intrahepatic portosystemic shunt(TIPS) to reduce portal venous pressure and control complications of portal hypertension.METHODS: From January 2011 to December 2012, 10 cirrhotic patients were treated for complications of portal hypertension. The demographic data, operative data, postoperative recovery data, hemodynamic data, and complications were analyzed.RESULTS: Ten patients underwent a primary and parallel TIPS. Technical success rate was 100% with no technical complications. The mean duration of the first operation was 89.20 ± 29.46 min and the second operation was 57.0 ± 12.99 min. The mean portal system pressure decreased from 54.80 ± 4.16 mmHg to 39.0 ± 3.20 mmHg after the primary TIPS and from 44.40 ± 3.95 mmHg to 26.10 ± 4.07 mmHg after the parallel TIPS creation. The mean portosystemic pressure gradi-ent decreased from 43.80 ± 6.18 mmHg to 31.90 ± 2.85 mmHg after the primary TIPS and from 35.60 ± 2.72 mmHg to 15.30 ± 3.27 mmHg after the parallel TIPS creation. Clinical improvement was seen in all patients after the parallel TIPS creation. One patient suffered from transient grade Ⅰ hepatic encephalopathy(HE) after the primary TIPS and four patients experienced transient grade Ⅰ-Ⅱ after the parallel TIPS procedure. Mean hospital stay after the first and second operations were 15.0 ± 3.71 d and 16.90 ± 5.11 d(P = 0.014), respectively. After a mean 14.0 ± 3.13 mo follow-up, ascites and bleeding were well controlled and no stenosis of the stents was found.CONCLUSION: Parallel TIPS is an effective approach for controlling portal hypertension complications.展开更多
Port-city system is a complex and integral system, and it can be simulated by system dynamic method, which is used to be employed to solve nonlinear problems. Based on the causality of the every element in the port-ci...Port-city system is a complex and integral system, and it can be simulated by system dynamic method, which is used to be employed to solve nonlinear problems. Based on the causality of the every element in the port-city system, the authors analyzed the feedback relation and logical relation among the system variables and system structure. A system-dynamic flow chart and correlation equations were put forward with VENSIM software, the quantitative relation was described, and the model was debugged. The development trend of the main influence factors in port-city system was simulated. By changing the parameters values of variables in the model, we studied the influence degree of each related factor. It is found that: 1) Foreign trade throughput of port play an important role in the development of export-oriented economy. 2) The development of primary industry and secondary industry affects most of the water transportation demand. With the constant increase of tertiary industry proportion in the industrial structure, the demand of national economy for water transportation decreases gradually. 3) Water transportation presents a kind of oversupply development situation, so port construction should properly slow down. 4) With the development of ports, its direct and indirect contribution to urban economy has been continuously increasing, but contribution rate will be continuously decreasing.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
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
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
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.
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BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly rare.Basilic vein variation usually presents without any clinical symptoms and is often regarded as a benign alteration.This case was a patient with congenital basilic vein variation encountered during surgery for an infusion port.CASE SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port insertion.This peculiarity has hitherto remained undescribed in the literature.We offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its occurrence.We conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port implantations.CONCLUSION Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment.
文摘In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area.
基金This research is supported by Hunan Provincial Natural Science Foundation of China(Grant No.2021JJ30304)the General Topics of Hunan Social Science Achievement Evaluation Committee of China(Grant No.XSP22YBC366)the Key Scientific Research Project of Hunan Provincial Department of Education of China(Grant No.21B0592).
文摘Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern China from 2000 to 2018,this study explores the coupling coordination development of port and city environments and its impact on urban economic competitiveness by constructing the coupling coordination degree model and the panel threshold model.The research results show that:(1)In terms of the coupling coordination development of port and city environments,most coastal ports and their hinterland cities are in a state of moderate or serious disorder.Overall,the degree of coupling coordination of port and city environments needs to be further improved;(2)The coupling coordination degree of port and city environments has a significant impact on urban economic competitiveness,and this effect gradually increases with the development of the ports and the urban economy.Among the variables that impact the urban economic competitiveness,fixed assets investment and foreign trade are significant factors that can enhance urban economic competitiveness.(3)At present,there is a“U-shaped”relationship between the coupling coordination degree of port-city environments and the urban economic competitiveness.This relationship lies on the right side of the inflection point of the“U-shaped”curve.Therefore,following the concept of assigning priority to ecological development,expanding fixed assets investment and actively developing foreign trade can further enhance the urban economic competitiveness.
文摘The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan.
文摘In order to explore and foster innovation in international exchange and cooperation,this study focuses on the background of the construction of the Hainan Free Trade Port.It delves into the current development status,characteristic demands,and potential challenges of its international exchange and cooperation mechanisms.Through a comprehensive analysis of relevant cases,survey questionnaires,and literature,this study aims to provide feasible innovative models and recommendations to promote the sustained development of the Hainan Free Trade Port in the field of international exchange and cooperation,injecting new vitality into China’s economic globalization.This exploration contributes to a deeper understanding of the development of free trade ports and provides insights and references for other countries and regions.
文摘AIM: To evaluate the feasibility of a second parallel transjugular intrahepatic portosystemic shunt(TIPS) to reduce portal venous pressure and control complications of portal hypertension.METHODS: From January 2011 to December 2012, 10 cirrhotic patients were treated for complications of portal hypertension. The demographic data, operative data, postoperative recovery data, hemodynamic data, and complications were analyzed.RESULTS: Ten patients underwent a primary and parallel TIPS. Technical success rate was 100% with no technical complications. The mean duration of the first operation was 89.20 ± 29.46 min and the second operation was 57.0 ± 12.99 min. The mean portal system pressure decreased from 54.80 ± 4.16 mmHg to 39.0 ± 3.20 mmHg after the primary TIPS and from 44.40 ± 3.95 mmHg to 26.10 ± 4.07 mmHg after the parallel TIPS creation. The mean portosystemic pressure gradi-ent decreased from 43.80 ± 6.18 mmHg to 31.90 ± 2.85 mmHg after the primary TIPS and from 35.60 ± 2.72 mmHg to 15.30 ± 3.27 mmHg after the parallel TIPS creation. Clinical improvement was seen in all patients after the parallel TIPS creation. One patient suffered from transient grade Ⅰ hepatic encephalopathy(HE) after the primary TIPS and four patients experienced transient grade Ⅰ-Ⅱ after the parallel TIPS procedure. Mean hospital stay after the first and second operations were 15.0 ± 3.71 d and 16.90 ± 5.11 d(P = 0.014), respectively. After a mean 14.0 ± 3.13 mo follow-up, ascites and bleeding were well controlled and no stenosis of the stents was found.CONCLUSION: Parallel TIPS is an effective approach for controlling portal hypertension complications.
基金Under the auspices of National Natural Science Foundation of China(No.40871063)
文摘Port-city system is a complex and integral system, and it can be simulated by system dynamic method, which is used to be employed to solve nonlinear problems. Based on the causality of the every element in the port-city system, the authors analyzed the feedback relation and logical relation among the system variables and system structure. A system-dynamic flow chart and correlation equations were put forward with VENSIM software, the quantitative relation was described, and the model was debugged. The development trend of the main influence factors in port-city system was simulated. By changing the parameters values of variables in the model, we studied the influence degree of each related factor. It is found that: 1) Foreign trade throughput of port play an important role in the development of export-oriented economy. 2) The development of primary industry and secondary industry affects most of the water transportation demand. With the constant increase of tertiary industry proportion in the industrial structure, the demand of national economy for water transportation decreases gradually. 3) Water transportation presents a kind of oversupply development situation, so port construction should properly slow down. 4) With the development of ports, its direct and indirect contribution to urban economy has been continuously increasing, but contribution rate will be continuously decreasing.
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.
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.