Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agi...Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hoist was constructed. The hydraulic pressure cylinder and the accumulator were analyzed and calculated. Finally, PRO/E and ADAMS were used to simulate the hoist and its hydraulic system. It was found that this type of virtual prototype provides a good method to actualize a physical prototype.展开更多
The risks in development of navy vessels were explored, The resources of technical risk in the design and development of vessels were mentioned, It was pointed that technical risk dominated the other risk components. ...The risks in development of navy vessels were explored, The resources of technical risk in the design and development of vessels were mentioned, It was pointed that technical risk dominated the other risk components. Based on the writers＇ understanding and experience from risk analysis and risk ,nanagement to the development of a navy vessel, four measure indexes of technical risk were presented. The decision criteria and the rules corresponding to the indexes were estahlished by the statistic information,展开更多
Radar cross section（RCS） is the measurement of the reflective strength of a target.Reducing the RCS of a naval ship enables its late detection,which is useful for capitalizing on elements of surprise and initiative....Radar cross section（RCS） is the measurement of the reflective strength of a target.Reducing the RCS of a naval ship enables its late detection,which is useful for capitalizing on elements of surprise and initiative.Thus,the RCS of a naval ship has become a very important design factor for achieving surprise,initiative,and survivability.Consequently,accurate RCS determination and RCS reduction are of extreme importance for a naval ship.The purpose of this paper is to provide an understanding of the theoretical background and engineering approach to deal with RCS prediction and reduction for naval ships.The importance of RCS,radar fundamentals,RCS basics,RCS prediction methods,and RCS reduction methods for naval ships is also discussed.展开更多
Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agi...Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hoist was constructed. The hydraulic pressure cylinder and the accumulator were analyzed and calculated. Finally, PRO/E and ADAMS were used to simulate the hoist and its hydraulic system. It was found that this type of virtuaU674.7l prototype provides a good method to actualize a physical prototype.展开更多
Naval ship deperming is effective to reduce the potential damage from sea mines some of which sense magnetic field of the ship, and thus, is an important treatment of naval ships in the recent world. Large electric cu...Naval ship deperming is effective to reduce the potential damage from sea mines some of which sense magnetic field of the ship, and thus, is an important treatment of naval ships in the recent world. Large electric current is required to impose the magnetic field on the ship hull, which in turn means that the deperming coil needs to be wound on ship hull when the coil is composed of conventional conductive materials, such as copper. We considered a few HTS （high temperature superconducting） coil systems to deperm naval ships because we expect the shorter deperming time and lower manual workload for ship deperming operation, compared conventional conductor coil systems. We have in the past presented a solution using a fiat two-coil system arranged on seabed with tightly bound HTS conductor by analytical calculation of magnetic field on the conductor. By considering present and already developed technologies, a conductor with cylindrically wound on the core arranged as fiat multi-turn coils on seabed was designed using analytical methods.展开更多
The problem of shore wash in environmental engineering is connected in particular with the effect of waves generated by the ships and fast speed boats. Another problem is protection of ＂Marines＂ with anchored boat a...The problem of shore wash in environmental engineering is connected in particular with the effect of waves generated by the ships and fast speed boats. Another problem is protection of ＂Marines＂ with anchored boat against waves. Sloping banks provoke unfavorable transformation of waves. Simultaneously sloping bank is the factor which significantly complicates prediction of wave pattern in numerical analysis. The purpose of present paper is to demonstrate the results of numerical investigation of ship waves pattern in constrain water area with slope banks by panel method for non-linear ship waves calculation usually applied for ship hull perfection as routine instrument of towing tanks technology. The method initially developed for calculation of ship hull waves in inviscid infinite fluid was adapted to meet boundary conditions on slope banks. Verification of the method was done for 60-series ship in rectangular channel. Development of wave pattern generated by two ship of different types--monohull ferries and river catamaran was investigated. It was found that ship waves height significantly increased due to slopping banks comparing with case of deep water and shallow water rectangular channel.展开更多
This paper describes the activities carried out by CETENA in collaboration with the Italian Navy to assess the behavior of new FREMM frigates by means of an automatic hull monitoring system and to predict the expected...This paper describes the activities carried out by CETENA in collaboration with the Italian Navy to assess the behavior of new FREMM frigates by means of an automatic hull monitoring system and to predict the expected fatigue life of ship structure by analyzing recorded data through a specifically developed post-processing tool.展开更多
THE 20th Chinese naval escort taskforce took over the escort mission in the Gulf of Aden from the 19th escort taskforce on April 22,2015.Since the end of 2008,under the authorization of the UN Security Council and the...THE 20th Chinese naval escort taskforce took over the escort mission in the Gulf of Aden from the 19th escort taskforce on April 22,2015.Since the end of 2008,under the authorization of the UN Security Council and the consent of the Somali government,China has carried out all such escort missions in the Gulf of Aden.To date,over 50 Chinese naval ships have been dispatched to the region and the taskforce has fulfilled over 800 missions of escorting more than 5,000 Chinese and foreign vessels.展开更多
Objective: To investigate the current status of medical support in military operations other than war (MOOTW) in domestic and overseas. Methods: This paper mainly adopts the descriptive, comparative and induction rese...Objective: To investigate the current status of medical support in military operations other than war (MOOTW) in domestic and overseas. Methods: This paper mainly adopts the descriptive, comparative and induction research methods. The current status of medical support in MOOTW in China, America, Russia, Israel, Canada, had been studied through some official papers, and series of professional books by analysis the precise date in various kinds of emergency event. Results: The contrast shows that there is still a quite huge development in medical support in MOOTW, no matter in China, or in other countries. Conclusion: In order to strengthen the forces, besides building professional rescue teams, it is necessary to take a regular revise of plans, according to missions` needs.展开更多
We consider the Navier-Stokes equations with a pressure function satisfying a hard-sphere law.That means the pressure,as a function of the density,becomes infinite when the density approaches a finite critical value.U...We consider the Navier-Stokes equations with a pressure function satisfying a hard-sphere law.That means the pressure,as a function of the density,becomes infinite when the density approaches a finite critical value.Under some structural constraints imposed on the pressure law,we show a weak-strong uniqueness principle in periodic spatial domains.The method is based on a modified relative entropy inequality for the system.The main difficulty is that the pressure potential associated with the internal energy of the system is largely dominated by the pressure itself in the area close to the critical density.As a result,several terms appearing in the relative energy inequality cannot be controlled by the total energy.展开更多
The authors study the asymptotic behavior of the incompressible Navier-Stokes fluid with degree of freedom in the porous medium in R^n with n = 2 or 3. They derive the Darcy law as ε, the character size of the hole, ...The authors study the asymptotic behavior of the incompressible Navier-Stokes fluid with degree of freedom in the porous medium in R^n with n = 2 or 3. They derive the Darcy law as ε, the character size of the hole, tends to zero. Moreover, the authors obtain the expression of the degree of freedom from the homogenized model.展开更多
Objective： To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods：We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 ...Objective： To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods：We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 and 115-125 days after voyage, and 29 men and 3 women for 5-15 days after having finished voyage. Results：NN50 and VLF were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage （P＆lt;0.01）. SDANN was lower in 77 men and 4 women for 115-125 days after voyage than that was 65-75 days after voyage （P＆lt;0.01）. SDNN, SDANN, SDNN index, RMSSD, NN50, PNN50,Triangular index, VLF, HLF, VAI and VLI were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage （P＆lt;0.01）.Conclusion： These findings suggest that voyage may reduce heart rate variability for a long time.展开更多
文摘Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hoist was constructed. The hydraulic pressure cylinder and the accumulator were analyzed and calculated. Finally, PRO/E and ADAMS were used to simulate the hoist and its hydraulic system. It was found that this type of virtual prototype provides a good method to actualize a physical prototype.
文摘The risks in development of navy vessels were explored, The resources of technical risk in the design and development of vessels were mentioned, It was pointed that technical risk dominated the other risk components. Based on the writers＇ understanding and experience from risk analysis and risk ,nanagement to the development of a navy vessel, four measure indexes of technical risk were presented. The decision criteria and the rules corresponding to the indexes were estahlished by the statistic information,
基金Supported by Program for New Century Excellent Talents in University under Grant No.NCET-07-0230the "111" Project under Grant No.B07019 at Harbin Engineering University
文摘Radar cross section（RCS） is the measurement of the reflective strength of a target.Reducing the RCS of a naval ship enables its late detection,which is useful for capitalizing on elements of surprise and initiative.Thus,the RCS of a naval ship has become a very important design factor for achieving surprise,initiative,and survivability.Consequently,accurate RCS determination and RCS reduction are of extreme importance for a naval ship.The purpose of this paper is to provide an understanding of the theoretical background and engineering approach to deal with RCS prediction and reduction for naval ships.The importance of RCS,radar fundamentals,RCS basics,RCS prediction methods,and RCS reduction methods for naval ships is also discussed.
文摘Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hoist was constructed. The hydraulic pressure cylinder and the accumulator were analyzed and calculated. Finally, PRO/E and ADAMS were used to simulate the hoist and its hydraulic system. It was found that this type of virtuaU674.7l prototype provides a good method to actualize a physical prototype.
文摘Naval ship deperming is effective to reduce the potential damage from sea mines some of which sense magnetic field of the ship, and thus, is an important treatment of naval ships in the recent world. Large electric current is required to impose the magnetic field on the ship hull, which in turn means that the deperming coil needs to be wound on ship hull when the coil is composed of conventional conductive materials, such as copper. We considered a few HTS （high temperature superconducting） coil systems to deperm naval ships because we expect the shorter deperming time and lower manual workload for ship deperming operation, compared conventional conductor coil systems. We have in the past presented a solution using a fiat two-coil system arranged on seabed with tightly bound HTS conductor by analytical calculation of magnetic field on the conductor. By considering present and already developed technologies, a conductor with cylindrically wound on the core arranged as fiat multi-turn coils on seabed was designed using analytical methods.
文摘The problem of shore wash in environmental engineering is connected in particular with the effect of waves generated by the ships and fast speed boats. Another problem is protection of ＂Marines＂ with anchored boat against waves. Sloping banks provoke unfavorable transformation of waves. Simultaneously sloping bank is the factor which significantly complicates prediction of wave pattern in numerical analysis. The purpose of present paper is to demonstrate the results of numerical investigation of ship waves pattern in constrain water area with slope banks by panel method for non-linear ship waves calculation usually applied for ship hull perfection as routine instrument of towing tanks technology. The method initially developed for calculation of ship hull waves in inviscid infinite fluid was adapted to meet boundary conditions on slope banks. Verification of the method was done for 60-series ship in rectangular channel. Development of wave pattern generated by two ship of different types--monohull ferries and river catamaran was investigated. It was found that ship waves height significantly increased due to slopping banks comparing with case of deep water and shallow water rectangular channel.
文摘This paper describes the activities carried out by CETENA in collaboration with the Italian Navy to assess the behavior of new FREMM frigates by means of an automatic hull monitoring system and to predict the expected fatigue life of ship structure by analyzing recorded data through a specifically developed post-processing tool.
文摘THE 20th Chinese naval escort taskforce took over the escort mission in the Gulf of Aden from the 19th escort taskforce on April 22,2015.Since the end of 2008,under the authorization of the UN Security Council and the consent of the Somali government,China has carried out all such escort missions in the Gulf of Aden.To date,over 50 Chinese naval ships have been dispatched to the region and the taskforce has fulfilled over 800 missions of escorting more than 5,000 Chinese and foreign vessels.
文摘Objective: To investigate the current status of medical support in military operations other than war (MOOTW) in domestic and overseas. Methods: This paper mainly adopts the descriptive, comparative and induction research methods. The current status of medical support in MOOTW in China, America, Russia, Israel, Canada, had been studied through some official papers, and series of professional books by analysis the precise date in various kinds of emergency event. Results: The contrast shows that there is still a quite huge development in medical support in MOOTW, no matter in China, or in other countries. Conclusion: In order to strengthen the forces, besides building professional rescue teams, it is necessary to take a regular revise of plans, according to missions` needs.
基金the European Research Council under the European Union’s Seventh Framework Programme (Grant No. FP7/2007-2013)European Research Council (ERC) Grant Agreement (Grant No. 320078)The Institute of Mathematics of the Academy of Sciences of the Czech Republic was supported by Rozvoj Vyzkumn Organizace (RVO) (Grant No. 67985840)
文摘We consider the Navier-Stokes equations with a pressure function satisfying a hard-sphere law.That means the pressure,as a function of the density,becomes infinite when the density approaches a finite critical value.Under some structural constraints imposed on the pressure law,we show a weak-strong uniqueness principle in periodic spatial domains.The method is based on a modified relative entropy inequality for the system.The main difficulty is that the pressure potential associated with the internal energy of the system is largely dominated by the pressure itself in the area close to the critical density.As a result,several terms appearing in the relative energy inequality cannot be controlled by the total energy.
基金supported by the Research of High Schools of Guangzhou(No.1201420925)Guangdong Natural Science Foundation(No.2014A030313526)
文摘The authors study the asymptotic behavior of the incompressible Navier-Stokes fluid with degree of freedom in the porous medium in R^n with n = 2 or 3. They derive the Darcy law as ε, the character size of the hole, tends to zero. Moreover, the authors obtain the expression of the degree of freedom from the homogenized model.
文摘Objective： To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods：We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 and 115-125 days after voyage, and 29 men and 3 women for 5-15 days after having finished voyage. Results：NN50 and VLF were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage （P＆lt;0.01）. SDANN was lower in 77 men and 4 women for 115-125 days after voyage than that was 65-75 days after voyage （P＆lt;0.01）. SDNN, SDANN, SDNN index, RMSSD, NN50, PNN50,Triangular index, VLF, HLF, VAI and VLI were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage （P＆lt;0.01）.Conclusion： These findings suggest that voyage may reduce heart rate variability for a long time.
