Tạp chí Khoa học công nghệ Giao thông vận tải

RESEARCH ON IMPROVED THE MULTI-OVERHEAD CRANE CONTROLLER BY USING PLC

2020-08-03T06:33:41+07:00

This paper presents researchs and designs to improve controller of multi-overhead crane system in a car assembly factory by using PLC. The abilitys of the new controller are automatic moving and lifting, it also has ability of automatic stopping to avoid suddenly collisions. The controller ensure to improve productivity and minimize of collisions that make to damage goods and equipment during handling. Tests at the factory showed that the improved system allowed an increase of 10-15% and there was no collision between cranes during loading. The overall evaluation of the results shows that the system works well, meeting all technical requirements.

NUMERICAL STUDY OF AN AUTONOMOUS UNDERWATER VEHICLE MOVEMENT

2020-08-03T06:33:47+07:00

Nowadays, the autonomous underwater vehicle is applied worldwide. It can be applied in the field of remote sensing, oceanographic research, environmental control, territorial protection. The ability to automatically control and flexibly react to the autonomous underwater vehicle has been affirmed in the role of submarine industrial base development. In this trend, the study investigates on simulating the effect of fluid flow on the profile of an autonomous underwater vehicle by computational fluid dynamics method. The numerical results indicate that an autonomous underwater vehicle profile determines the drag and the largest stress occurs at the head of autonomous underwater vehicle when it moves. In addition, the effect of the wing profile on the drag and rotation angle of the autonomous underwater vehicle is also explored in this study.

RESEARCH OSCILLATION OF ANGULAR VELOCITY OF INTERNAL COMBUSTION CRANKSHAFT BY EXPERIMENT METHOD ON ENGINE 1Ч17,5/24

2020-08-03T06:33:54+07:00

In this study, we have shown causes to lead to a change of angular velocity of internal combustion crankshaft, theoretical basis analysis leads to a change of angular velocity of internal combustion crankshaft in working cycle of the engine and its influence. Then we conduct experimental measurement on the engine 1Ч17,5/24 in the case of the load modes. from measured results we conduct an analysis of these results and plot diagrams of the change of angular velocity of a crankshaft in the load modes, as well as calculate the coefficient ẟ for each loading mode, the results showed that the change of impulse torque by using the device, which supplies fuel at many times, then the fuel and air are better blended, making the combustion process more stable.

A COMPARISON OF THE STABILITY OF THE SHIP AUTOPILOT SYSTEM USING PSO-PID AND FUZZY ALGORITHMS

2020-08-03T06:33:58+07:00

The control objective of the ship control system is to control the heading and change of direction of the ship to follow up the desired heading under the effect of external factors acting on the ship. In this paper, we study the stability of a ship autopilot system based on the PSO-PID control algorithm and the Fuzzy control algorithm under the effects of environmental disturbances, including current, wind, wave, and high-frequency wave noise. Especially, the parameters of the factors affecting the ship were surveyed by the actual conditions of the Vietnam sea environment from Binh Thuan province to Ca Mau province, which can increase the reliability of the proposed algorithm. The performance of the algorithms was evaluated through simulation results using Matlab/Simulink software.

DUST CONTROL SOLUTIONS IN CEMENT PRODUCTION LINE IN VIETNAM

2020-08-03T06:34:03+07:00

Controlling dust in industrial production environments is always a pressing issue for businesses, branches, and levels. The document of the 12th National Party Congress 2016 again demonstrated the Party's consistent viewpoint on environmental protection, that is to limit and proceed to overcome the state of destruction and environmental pollution of production establishments and industrial parks, finally to end the situation of environmental pollution, enhance prevention and control of sources of environmental pollution ...

In our country, there are up to hundreds of cement factories with new and old technology applied. Dust in the production and transportation environment of cement and materials is particularly dangerous to human health and surrounding ecosystems. Knowing so many recommendations, calling from the realities of people's lives, but because of economic pressure, the livelihood of living, sustainable development is exchanged. The contribution of the community from the understanding of the situation, propagating and disseminating knowledge, planning appropriate investment, construction, production, and contributing or providing solutions to solve problems pollution is an important goal of coming up with the root of the problem. This paper presents some studies on technical issues in the design of plant transport chains, new solutions for dust control.

RESEARCH DYNAMIC THERMAL AND DYNAMIC TO HYDRO CORROSION PROCESS AT HIGH TEMPERATURE WITH PIPES STEEL IN H2SO4 ACID FACTORY

2020-08-03T06:34:11+07:00

The article introduces the phenomenon of Hydro corrosion with steel when in the conditions of high temperature and pressure, especially piping systems in chemical factories. Based on the thermodynamic analysis, the reactions between Hydro and the steel surface layer have identified the conditions and trends of Hydro corrosion due to the influence of the temperature and working pressure of the pipeline. To creating practical applicability, the paper introduced the method of building mathematical models according to kinetic rules to develop the Hydro steel pipe corrosion process at high temperature and pressure. Mathematical models built in combination with boundary conditions determined according to production reality will allow a fairly accurate calculation of the life of the piping system or the erosion due to corrosion over time. If the temperature is above 200^oC, hydrogen corrosion can be ignored. However, if the temperature is above 300 ° C, hydrogen corrosion will significantly be affected. The model also shows the dependence of hydrogen corrosion on temperature and pressure.

RESEARCH SETTING FORMULA’S STARTING TEMPERATURE OF MARTENSITE TRANSFORMATION (MS) FOR STEEL BY CHEMICAL COMPOSITION

2020-08-03T06:34:15+07:00

The article researches the method and implements the formulation of an empirical formula to approximate the starting temperature of martensite transformation (M_S) of steel according to the composition chemical of steel based on statistics and shape tone of experimental curves. The results of the study have allowed us to determine the coefficient that affects the starting temperature of the martensite transformation of alloy elements in steel in the shape of experimental curves. With these coefficients, we have formulated two formulas which calculated the start temperature martensite transformations with the effect of alloy elements in two different carbon content ranges. Applying these formulas calculates the application for a specific grade of steel that is perfectly suitable and highly applicable in many fields from steel production research to determine the state of steel after heat treatment like as automating the heat treatment process. According to the research results, the empirical formula was used to calculate the martensitic transformation temperature for some steel of groups; Since then determine the appropriate cooling environment.

RESEARCH ON ESTIMATION OF Su FROM SPT RESULTS FOR CALCULATING THE PILE BEARING CAPACITY

2020-08-03T06:34:19+07:00

This paper presents a study on assessment, estimation of the undrained shear strength (S_u) of clayey soils in Soc Trang province from Standard Penetration Test (SPT) results, and application for calculating the pile ultimate axial compression bearing capacity according to current standards TCVN 10304-2014 and TCVN 11823-2017, in cooperation with static pile loading test results. The calculating and comparative process is applied to some constructions such as small bridges on rural roads network, schools, offices… in Soc Trang province.

STABILITY OF THE COLUMN WITH CHANGED LINEAR CROSS SECTIONS BY MATRIX STIFFNESS METHOD

2020-08-03T06:34:24+07:00

In the paper, the author constructed the stiffness matrix of bending compressive elements whose cross-section changes according to the first-order rule, the displacement function selected as the third polynomial satisfying the boundary conditions of the problem. The stiffness matrix of simultaneously compressible bending elements includes: The hardness matrix of a common linear elastic bar element has a linear change cross-section and a stiffness matrix of the inner rod element. it takes into account the effect of longitudinal force P on the element flexural stiffness. Payload P acts at both ends of the element. The overall hardness matrix is determined by the index method, the critical load is determined by the specific value problem of the overall hardness matrix.

SHAPE OPTIMIZATION OF RETAINING WALLS

2020-08-03T06:34:27+07:00

The article presents the optimal shape of gravity retaining walls and cantilever retaining walls based on the combining between the Differential Evolution method and theories of Rankin and Coulomb for earth pressures. The optimal retaining walls, which are subjected to common loads such as dead loads, equivalent live loads and earth pressures, have the least material cost. They also satisfy all requirements on the safety of sliding, the safety of overturning and safety of soil bearing capacity. In addition, the cantilever retaining walls meet the safety of flexural strength and shear strength. The article also presents the optimal retaining walls with various values of parameters such as wall height, soil bearing capacity, angle of internal friction of backfill, equivalent live load and slope of backfill surface.

DESCRIPTION OF SEARCH AND RESCUE SERVICE IN DIGITAL WORLD

2020-08-03T06:34:30+07:00

Responsibilities and obligations for search and rescue in the sea that the coastal State management stipulated in the International Convention for the Safety of Life at Sea (SOLAS 74), the International Convention on Search and Rescue at sea (SAR 79) and a series of international legal instruments other. As the navigation sector is moving into the digital world, e-Navigation is expected to provide digital information and infrastructure for the benefit of maritime safety, security, and protection of the marine environment, reducing the administrative burden and increasing the efficiency of maritime trade and transport. The Maritime Safety Committee (MSC) adopted Resolution MSC.467 (101) and MSC.1/Circ.1610, guiding the definition of the harmonization of the structure of maritime services in the scene of E-Navigation and agreed to consolidate descriptions of maritime services and review them together with other relevant international organizations and the Member States, to harmonize the provision and exchange of maritime information and data. This article describes search and rescue service, contributing to the improvement of search and rescue effectiveness on Vietnam's waters.

IMPLEMENTATION OF MARITIME SERVICES IN E-NAVIGATION: DESCRIPTION OF PILOTAGE AND TUG SERVICES

2020-08-03T06:34:36+07:00

As the shipping industry moves into the digital world, e-Navigation is expected to provide digital information and infrastructure for the benefit of maritime safety, security, and protection of the marine environment, reducing the administrative burden and increasing the efficiency of maritime trade and transport. The Maritime Safety Committee (MSC) adopted Resolution MSC.467 (101) at the 101st session of the International Maritime Organization (IMO), providing guidance on the definition of the harmonization of the structure of maritime services in the scene of e-Navigation and agreed to consolidate descriptions of maritime services and review them together with other relevant international organizations and the Member States, to harmonize the provision and exchange of maritime information and data. The initial description of maritime services such as pilots and tug services has been approved by MSC at MSC.1/Circ.1610, and is expected to be updated in the next period.

SOLUTIONS TO IMPROVE THE TRANSPORT PROCESSES OF TEMPORARY IMPORT-RE-EXPORT OF GOODS BY ROAD BETWEEN VIETNAM AND CAMBODIA

2020-08-03T06:34:38+07:00

Currently, transporting temporary import-re-export commodities of Vietnamese and Cambodian companies through those Southern Seaports of Vietnam are implemented by Vietnamese transportation companies. Those logistics services go along with transportation services are rather various and developing. At first, offering logistics services to temporary import-export commodities to Cambodia should be opportunities and new business orientation for Vietnam logistics companies in Southern East Area. However, in fact, there are some shortcomings and difficulties raised recently. This study is aimed evaluating current situation to find the advantages and difficulties of delivery processes to propose solutions to orient and develop delivery services of Vietnam to type of temporary import-reexport goods between Vietnam and Cambodia.

SOLUTIONS TO IMPLEMENT RICE EXPORT SALES CONTRACTS OF VIETNAM EXPORT COMPANIES DURING COVID - 19 DISASE PERIOD

2020-08-03T06:34:42+07:00

For a long time ago, Vietnam became a large rice exporter in over the world. Those rice export contracts are always interested by many ministry officials, especially Agriculture ministry and Industry- Trade ministry. After COVID - 19 disease outbreak globally, food demand is one of the most important priorities for all countries. In such a situation, having the strenths in agriculture, Vietnam plays a very important role in supplying food to the world. Vietnam’s rice export not only keeps food safety but also bring more profits to farmers. This study is aimed at searching processes to implement and analyze rice export contracts of most rice export companies to find out solutions for processes improvement in COVID - 19 disease period.

CURRENT SITUATION AND NIGHT ECONOMIC SOLUTION IN HO CHI MINH CITY

2020-08-03T06:34:45+07:00

Ho Chi Minh City is one of the cities dubbed the "sleepless city", the night economic development here has created a great source of income for the urban population, while attracting tourists, businessmen come to do business, invest ... Night economic activity is very bustling with many activities such as walking street, food street, night market ..., the latest is the explosion of the door system. convenience goods. In the long term, Ho Chi Minh City needs an in-depth project on night streets, shopping centers, convenience stores, nightclubs, clubs, live music concerts, entertainment, and cultural forms. at night. The paper analyzes the current situation of advantages, difficulties, opportunities, and challenges in Ho Chi Minh City in attracting annual visitors, and the author has proposed some measures to help develop the background. Night economy in Ho Chi Minh City in a new stage.

DETERMINING FACTORS AFFECTING THE QUALITY OF THE BASIC DESIGN OF TRANSPORT INFRASTRUCTURE PROJECTS IN HO CHI MINH CITY

2020-08-03T06:34:49+07:00

The paper presents identified factors affecting the quality of the Basic Design of transport infrastructure projects in Ho Chi Minh City. The questionnaire survey was carried out in Ho Chi Minh City with many experts coming from consulting companies, owners, government agencies. 190 samples were sent to participants and 140 received. There are six-factor groups identified, including consulting companies for studying project feasibilities, owners, project budget, standards – legal, the consistent of basic design, detail design, and technology. The influencing level of the factors is assessed by using Exploratory Factor Analysis EFA. This result plays an important role in producing effective solutions.

INTERNATIONAL LEGAL FRAMEWORK AND MEASURES TAKEN TO SUPPRESS SOMALIA PIRACY IN THE PERIOD 2005 - 2015

2020-08-03T06:34:53+07:00

Piracy of Somalia has emerged in the 2000s and flourished for about seven years from 2005 to 2012, mainly focused on hijacking vessels and its crew members for ransom purpose. And the ransom payments amounting to $238 million during the peak years of piracy. Piracy activities conducted off the coast of Somalia have evidenced some unique features, other than the usual features of the ancient piracy or piracy conducted elsewhere. These unique features have been made possible due to the political state of Somalia. And since 2015, pirates have tended to move and become active in West Africa. This article analyzes the said unique features of piracy activities conducted off the coast of Somalia, and the international legal framework measures are taken to suppress Somalia piracy in the period 2005 - 2015. Hereby opening up further research, those measures of Somalia can be lessons in dealing with growing piracy in West Africa.

DISCUSSION ON A FEW CONTENTS AND SENTENCES IN THE VIET NAM MARTIME LAW CODE 2015

2020-08-03T06:34:56+07:00

Maritime law code 3^rd edition has approved by the National Assembly of Vietnam in 2015. Maritime law Code 3^rd edition has been rather perfect so still has shortcomings of content and sentence. This article discusses some contents and sentences used in The Maritime law Code 2015 such as content concern relate rules for using the law; transport service price; vocabulary of a fixed-route ship; fact transport service price; discharging time; right canceling voyage charter party; vocabulary of with average and no average, with wanting to contribute to do the Maritime Law Code has been rather perfect conformity with the development trend of the era in management, ship operation, and shipping.