Rules of Classification Societies all around the world have made changes on design wave loads' value and fatigue influence factor modification due to the influence of springing and whipping on ultra-large containe...Rules of Classification Societies all around the world have made changes on design wave loads' value and fatigue influence factor modification due to the influence of springing and whipping on ultra-large containerships.The paper firstly introduced 3-D linear hydroelastic theory in frequency domain and 3-D nonlinear hydroelastic theory in time domain, considering large amplitude motion nonlinearity and slamming force due to the severe relative motion between ship hull and wave. Then the spectrum analysis method and time domain statistical analysis method were introduced, which can make fatigue analysis under a series of standard steps in frequency and time domain, respectively. Finally, discussions on the influence factor of springing and whipping on fatigue damages of 8500 TEU and 10000 TEU containerships with different loading states were made. The fatigue assessment of different position on the midship section was done on the basis of nominal stress. The fatigue damage due to whipping can be the same as the fatigue damage due to springing and even sometimes can be larger than the springing damage. Besides, some suggestions on calculating load case selection were made to minimize the quantity of work in frequency and time domain. Thus, tools for fatigue influence factor modification were provided to meet the demand of IACS-UR.展开更多
The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier...The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier's response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier's springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.展开更多
In Chinese culture,the horse is a symbol of vigor,strength,and resilience,heralding a future of steady progress and prosperous development,President Xi Jinping said when extending Spring Festival greetings at a recept...In Chinese culture,the horse is a symbol of vigor,strength,and resilience,heralding a future of steady progress and prosperous development,President Xi Jinping said when extending Spring Festival greetings at a reception on February 14 in Beijing to ring in the Chinese New Year-the Year of the Horse.This statement,resonating with the heart of the world’s most populous national celebration,offers a profound lens through which to understand not just a festival,but the pulsating energy of contemporary China.展开更多
A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 pol...A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs.展开更多
Hi Kazak Autonomous Prefecture is situated in the northwestern region of Northwest China's Xinjiang Uygur Autonomous Region.Ili not only boasts beautiful natural landscapes,such as colorful oceans of flowers,vast ...Hi Kazak Autonomous Prefecture is situated in the northwestern region of Northwest China's Xinjiang Uygur Autonomous Region.Ili not only boasts beautiful natural landscapes,such as colorful oceans of flowers,vast grasslands,and lofty snow mountains,it is also known for its profound historical and cultural heritage。展开更多
The Spring Festival,the oldest and most important traditional festival in Chinese culture,has been added to the United Nations Educational,Scientific and Cultural Organization(UNESCO)heritage list.On December 4,UNESCO...The Spring Festival,the oldest and most important traditional festival in Chinese culture,has been added to the United Nations Educational,Scientific and Cultural Organization(UNESCO)heritage list.On December 4,UNESCO announced its recognition of the Spring Festival,social practices celebrated by the Chinese people during the traditional lunisolar New Year,as an Intangible Cultural Heritage of Humanity during the 19th Session of the Intergovernmental Committee for Safeguarding Intangible Cultural Heritage in Asuncion,Paraguay.展开更多
The Spring Equinox,the fourth Chinese solar term out of 24,symbolizes hope,renewal and the promise of a bountiful harvest.As daylight begins to exceed nighttime and the Sun travels northward,it represents the awakenin...The Spring Equinox,the fourth Chinese solar term out of 24,symbolizes hope,renewal and the promise of a bountiful harvest.As daylight begins to exceed nighttime and the Sun travels northward,it represents the awakening of nature,growth,and new beginnings.展开更多
文摘Rules of Classification Societies all around the world have made changes on design wave loads' value and fatigue influence factor modification due to the influence of springing and whipping on ultra-large containerships.The paper firstly introduced 3-D linear hydroelastic theory in frequency domain and 3-D nonlinear hydroelastic theory in time domain, considering large amplitude motion nonlinearity and slamming force due to the severe relative motion between ship hull and wave. Then the spectrum analysis method and time domain statistical analysis method were introduced, which can make fatigue analysis under a series of standard steps in frequency and time domain, respectively. Finally, discussions on the influence factor of springing and whipping on fatigue damages of 8500 TEU and 10000 TEU containerships with different loading states were made. The fatigue assessment of different position on the midship section was done on the basis of nominal stress. The fatigue damage due to whipping can be the same as the fatigue damage due to springing and even sometimes can be larger than the springing damage. Besides, some suggestions on calculating load case selection were made to minimize the quantity of work in frequency and time domain. Thus, tools for fatigue influence factor modification were provided to meet the demand of IACS-UR.
基金Supported by the National Natural Science Foundation of China （Grant No. 51079034）, and the National Basic Research Program of China （Grant No. 2011CB013703）
文摘The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier's response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier's springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.
文摘In Chinese culture,the horse is a symbol of vigor,strength,and resilience,heralding a future of steady progress and prosperous development,President Xi Jinping said when extending Spring Festival greetings at a reception on February 14 in Beijing to ring in the Chinese New Year-the Year of the Horse.This statement,resonating with the heart of the world’s most populous national celebration,offers a profound lens through which to understand not just a festival,but the pulsating energy of contemporary China.
基金supported by the National Natural Science Foundation of China(No.51939009)Shenzhen Science and Technology Program(Nos.JCYJ20241202125905008 and GXWD20201231165807007-20200810165349001).
文摘A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs.
文摘Hi Kazak Autonomous Prefecture is situated in the northwestern region of Northwest China's Xinjiang Uygur Autonomous Region.Ili not only boasts beautiful natural landscapes,such as colorful oceans of flowers,vast grasslands,and lofty snow mountains,it is also known for its profound historical and cultural heritage。
文摘The Spring Festival,the oldest and most important traditional festival in Chinese culture,has been added to the United Nations Educational,Scientific and Cultural Organization(UNESCO)heritage list.On December 4,UNESCO announced its recognition of the Spring Festival,social practices celebrated by the Chinese people during the traditional lunisolar New Year,as an Intangible Cultural Heritage of Humanity during the 19th Session of the Intergovernmental Committee for Safeguarding Intangible Cultural Heritage in Asuncion,Paraguay.
文摘The Spring Equinox,the fourth Chinese solar term out of 24,symbolizes hope,renewal and the promise of a bountiful harvest.As daylight begins to exceed nighttime and the Sun travels northward,it represents the awakening of nature,growth,and new beginnings.
