In the 1940s,Wang Zhenduo王振铎re-created the sinan司南(southpointing loadstone spoon)mentioned in ancient texts.However,subsequent researchers were unsuccessful in their attempts to replicate this design,resulting in...In the 1940s,Wang Zhenduo王振铎re-created the sinan司南(southpointing loadstone spoon)mentioned in ancient texts.However,subsequent researchers were unsuccessful in their attempts to replicate this design,resulting in longstanding questions over its feasibility.Loadstones with high natural remanent magnetization acquired today resemble the magnetism of those recorded in premodern Chinese documents.By simulating ancient stoneware processing techniques,a loadstone was cut and polished into a spoon shape.It was found that during the course of processing the loadstone spoon,demagnetization was negligible,while after completion,the internal magnetic field was rebalanced due to the change in shape,and the magnetic moment decreased slightly then stabilized for the long term.Experiments of this sort carried out by the author have testified to the enduring and reliable directivity of the resulting loadstone spoon.Paleo-magnetic research indicates that over the past two millennia the horizontal component of the geomagnetic field intensity in northern China underwent a clear M-shaped development.The level in the Qin and Han dynasties is approximately double that of the current day.Using a simulated ancient geomagnetic field,experiments have revealed that multiple methods,such as the“water floating method”and“hanging method,”could manifest a degree of geo-directivity.The comprehensive studies carried out demonstrate that the loadstone spoon is the most optimal among these diverse means for attaining magnetic directivity from the Pre-Qin period(before 221 BCE)to the Tang dynasty(618–907 CE)in view of the availability of loadstone,the state of the geomagnetic field,and existing knowledge and techniques。展开更多
Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affi...Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.展开更多
针对木勺模压生产线,生产过程中一次性木勺在模具中产生遗料现象,利用相关图像识别技术,设计了一种在木勺生产过程中使用的遗料识别系统。以Raspberry Pi 4B作为控制板,利用Python设计编写相关遗料识别程序。利用该程序对相关图像进行...针对木勺模压生产线,生产过程中一次性木勺在模具中产生遗料现象,利用相关图像识别技术,设计了一种在木勺生产过程中使用的遗料识别系统。以Raspberry Pi 4B作为控制板,利用Python设计编写相关遗料识别程序。利用该程序对相关图像进行霍夫圆检测以及透视变换的处理,借以帧差法对比图像与图像之间的差异从而判断模具中有无遗料。实验证明,编写的遗料识别程序可以满足预期生产要求,程序的准确率接近100%,稳定性好。展开更多
Foreign-body ingestion is a relatively common presentation at emergency departments,but long metallic spoon swallowing is an infrequent occurrence.Unlike most cases of foreign-body ingestion,there have been no reporte...Foreign-body ingestion is a relatively common presentation at emergency departments,but long metallic spoon swallowing is an infrequent occurrence.Unlike most cases of foreign-body ingestion,there have been no reported cases of long foreign bodies reaching the jejunum.We report a rare case of a coffee spoon that was swallowed accidentally and passed through the pylorus and duodenal loop and reached the jejunum,with no complications.展开更多
文摘In the 1940s,Wang Zhenduo王振铎re-created the sinan司南(southpointing loadstone spoon)mentioned in ancient texts.However,subsequent researchers were unsuccessful in their attempts to replicate this design,resulting in longstanding questions over its feasibility.Loadstones with high natural remanent magnetization acquired today resemble the magnetism of those recorded in premodern Chinese documents.By simulating ancient stoneware processing techniques,a loadstone was cut and polished into a spoon shape.It was found that during the course of processing the loadstone spoon,demagnetization was negligible,while after completion,the internal magnetic field was rebalanced due to the change in shape,and the magnetic moment decreased slightly then stabilized for the long term.Experiments of this sort carried out by the author have testified to the enduring and reliable directivity of the resulting loadstone spoon.Paleo-magnetic research indicates that over the past two millennia the horizontal component of the geomagnetic field intensity in northern China underwent a clear M-shaped development.The level in the Qin and Han dynasties is approximately double that of the current day.Using a simulated ancient geomagnetic field,experiments have revealed that multiple methods,such as the“water floating method”and“hanging method,”could manifest a degree of geo-directivity.The comprehensive studies carried out demonstrate that the loadstone spoon is the most optimal among these diverse means for attaining magnetic directivity from the Pre-Qin period(before 221 BCE)to the Tang dynasty(618–907 CE)in view of the availability of loadstone,the state of the geomagnetic field,and existing knowledge and techniques。
基金Sponsored by 2022 Teaching Reform Project of Lingnan Normal University(000302201830)2022 Model Course of Lingnan Normal University(LingShiJiaoWu(2014)No.125)2023 Undergraduate Students’Innovation and entrepreneurship Planning of Lingnan Normal University(X202310579049X).
文摘Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.
文摘针对木勺模压生产线,生产过程中一次性木勺在模具中产生遗料现象,利用相关图像识别技术,设计了一种在木勺生产过程中使用的遗料识别系统。以Raspberry Pi 4B作为控制板,利用Python设计编写相关遗料识别程序。利用该程序对相关图像进行霍夫圆检测以及透视变换的处理,借以帧差法对比图像与图像之间的差异从而判断模具中有无遗料。实验证明,编写的遗料识别程序可以满足预期生产要求,程序的准确率接近100%,稳定性好。
文摘Foreign-body ingestion is a relatively common presentation at emergency departments,but long metallic spoon swallowing is an infrequent occurrence.Unlike most cases of foreign-body ingestion,there have been no reported cases of long foreign bodies reaching the jejunum.We report a rare case of a coffee spoon that was swallowed accidentally and passed through the pylorus and duodenal loop and reached the jejunum,with no complications.