Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in ot...Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.展开更多
This paper investigates the effects of the physical properties on the microstructure and weldability of explosive welding by joining two metals with a significant contrast in thermophysical properties:stainless steel ...This paper investigates the effects of the physical properties on the microstructure and weldability of explosive welding by joining two metals with a significant contrast in thermophysical properties:stainless steel and copper.Sound welds between stainless steel and copper were obtained,and the interfacial morphology was wavy,regardless of the position of the materials.The weldability of dissimilar pairs was found to be more dependent on the relationship between the physical properties of the base materials than on the absolute value of the material property.When there is a significant difference in thermal conductivity between the flyer and the base plate,together with a material with a low melting temperature,the weldability of the pair is often poor.The relative position of the plates affects the interfacial microstructure even when similar morphologies are found.For the metallic pairs studied,the wave size was bigger for the configuration in which the ratio between the density of the flyer and the density of the base plate is smaller.The same phenomenon was observed for the impedance:bigger waves were found for a smaller ratio between the impedance of the flyer and the impedance of the base plate.展开更多
Oral and maxillofacial surgery have a long history dating back to ancient civilizations such as the Egyptians. Since then, surgeons have treated craniofacial trauma and alveolodental fractures. In 1846, Hullihen perfo...Oral and maxillofacial surgery have a long history dating back to ancient civilizations such as the Egyptians. Since then, surgeons have treated craniofacial trauma and alveolodental fractures. In 1846, Hullihen performed a mandibular body osteotomy to correct prognathism, marking a significant milestone in the field. Over time, the specialty has evolved significantly. The field of craniofacial surgery has undergone several phases, including its involvement in conflicts during world wars and the treatment of craniofacial fractures and discrepancies. The process of learning and teaching specialties has evolved differently in various countries throughout the 20th century. Currently, there is no uniformity in the training and registration of specialized professionals, resulting in distinct scenarios. Considering the accessibility of scientific knowledge through technology and globalization, it is crucial to provide an objective overview of the current state of education in the field. This paper focuses on effective professional training as the primary subject of residency courses in this specialty. A proposal is presented for education, emphasizing the significance of providing quality professional training that is tailored to the specific legislation of each country.展开更多
As people grow older, their cognitive functions undergo changes which may result in uncomfortable driving situations and even increase the risk of accidents. This research aims to understand the neuropsychological asp...As people grow older, their cognitive functions undergo changes which may result in uncomfortable driving situations and even increase the risk of accidents. This research aims to understand the neuropsychological aspects of healthy aging and their possible relationship <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> changes in motor performance or ability. The research methodology is descriptive and includes a collection of basic studies in the scope of neuroscience, driving tasks, and older driver behavior. The final analysis points to certain changes in the functioning of the cerebral cortex and its connections as being responsible for poor performance in some basic driving tasks, but which can be compensated for by means of adapted mechanisms in motor vehicles. This study may contribute as a methodological tool, to the automobile design process, for the selection of Advanced Driver Assistance Systems (ADAS) or other emerging technologies which can compensate cognitive changes, improve safety, comfort and inclusion of older drivers in the future of automobile interior design. We conclude that in normal aging, people may present some cognitive deficits especially linked to the frontal and parietal lobe, which interfere with the necessary driving skills albeit not with the dangerous ones and can be compensated by technological solutions. The main innovation of this article is related to the bibliographical compilation and critical analysis in terms of identifying the neuropsychological aspects of normal human aging and car driving and its relationship with possible contributions from vehicular technology, as well its consider future trends in automotive interior design that should be analysed with caution in order to users inclusion.</span></span></span>展开更多
This research aims to understand the psychological, the social and cognitive aspects of ageing and assess the relevance of driving a personal automobile to seniors. We know that biological ageing is an inescapable fac...This research aims to understand the psychological, the social and cognitive aspects of ageing and assess the relevance of driving a personal automobile to seniors. We know that biological ageing is an inescapable fact, but is there also a psychological and a cognitive ageing？ If so, is it related to getting older or to other factors？ How relevant is continuing to drive to seniors, and how can the activity influence psychological and cognitive types of their ageing and self well-being？ To answer these questions, we study several authors and concepts about mental health, development of ageing and their relationship to driving. We also explore psychological and cognitive changes associated with ageing, the principal behavioural changes of healthy senior people （with normal cognitive function） and MCI （mild cognitive impairment）, as well as how driving inhibition can induce and affect psychological and cognitive characteristics. We conclude that low mental functioning is caused by a set of biological, psychological and social factors, connected in turn to environmental factors. The slowdown of cognitive activities and performances in seniors is not inevitably accompanied by a decrease in intellectual capacity, low sensory acuity, or slowing psychomotor skills. Other factors should be considered--such as health status, limitations, anxiety, lack of interest, motivation and attitudes. The loss of cognitive abilities and the prevalence of mild cognitive impairment increase with age and are a growing concern, especially among seniors who drive cars. However, we still lack specific evidence based on tests and criteria--in particular, on psychological and cognitive domains--to assess senior drivers actually at risk. It is important to establish a base of evidence to allow objective risk determination. The safest senior drivers should continue driving for as long as possible, thereby contributing to their mental health, independence and quality of life.展开更多
The main objective of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube （CFST） columns made with Rubberized Concrete （RuC）, and to assess the seismic performance ...The main objective of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube （CFST） columns made with Rubberized Concrete （RuC）, and to assess the seismic performance of moment-resisting frames with these structural members. The paper describes an experimental campaign where a total of 36 specimens were tested, resorting to a novel testing setup, aimed at reducing both the preparation time and cost of the test specimens. Different geometrical and material parameters were considered, namely cross-section type, cross-section slenderness, aggregate replacement ratio, axial load level and lateral loading type. The members were tested under both monotonic and cyclic lateral loading, with different levels of applied axial loading. The test results show that the bending behaviour of CFST elements is highly dependent on the steel tube properties and that the type of infill does not have a significant influence on the flexural behaviour of the member. It is also found that Eurocode 4 is conservative in predicting the flexural capacity of the tested specimens. Additionally, it was found that the seismic design of composite moment- resisting frames with CFST columns, according to Eurocode 8, not only leads to lighter design solutions but also to enhanced seismic performance in comparison to steel frames.展开更多
A novel color image encryption algorithm based on dynamic deoxyribonucleic acid(DNA)encoding and chaos is presented.A three-neuron fractional-order discrete Hopfield neural network(FODHNN)is employed as a pseudo-rando...A novel color image encryption algorithm based on dynamic deoxyribonucleic acid(DNA)encoding and chaos is presented.A three-neuron fractional-order discrete Hopfield neural network(FODHNN)is employed as a pseudo-random chaotic sequence generator.Its initial value is obtained with the secret key generated by a fiveparameter external key and a hash code of the plain image.The external key includes both the FODHNN discrete step size and order.The hash is computed with the SHA-2 function.This ensures a large secret key space and improves the algorithm sensitivity to the plain image.Furthermore,a new three-dimensional projection confusion method is proposed to scramble the pixels among red,green,and blue color components.DNA encoding and diffusion are used to diffuse the image information.Pseudo-random sequences generated by FODHNN are employed to determine the encoding rules for each pixel and to ensure the diversity of the encoding methods.Finally,confusion II and XOR are used to ensure the security of the encryption.Experimental results and the security analysis show that the proposed algorithm has better performance than those reported in the literature and can resist typical attacks.展开更多
基金supported by the Project IPL/2016/Soft Imob/ISEL and Project LAETA—UID/EMS/50022/2019
文摘Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.
基金sponsored by FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividadeby national funds through FCT-Funda??o para a Ciência e a Tecnologia,under the project UIDB/00285/2020。
文摘This paper investigates the effects of the physical properties on the microstructure and weldability of explosive welding by joining two metals with a significant contrast in thermophysical properties:stainless steel and copper.Sound welds between stainless steel and copper were obtained,and the interfacial morphology was wavy,regardless of the position of the materials.The weldability of dissimilar pairs was found to be more dependent on the relationship between the physical properties of the base materials than on the absolute value of the material property.When there is a significant difference in thermal conductivity between the flyer and the base plate,together with a material with a low melting temperature,the weldability of the pair is often poor.The relative position of the plates affects the interfacial microstructure even when similar morphologies are found.For the metallic pairs studied,the wave size was bigger for the configuration in which the ratio between the density of the flyer and the density of the base plate is smaller.The same phenomenon was observed for the impedance:bigger waves were found for a smaller ratio between the impedance of the flyer and the impedance of the base plate.
文摘Oral and maxillofacial surgery have a long history dating back to ancient civilizations such as the Egyptians. Since then, surgeons have treated craniofacial trauma and alveolodental fractures. In 1846, Hullihen performed a mandibular body osteotomy to correct prognathism, marking a significant milestone in the field. Over time, the specialty has evolved significantly. The field of craniofacial surgery has undergone several phases, including its involvement in conflicts during world wars and the treatment of craniofacial fractures and discrepancies. The process of learning and teaching specialties has evolved differently in various countries throughout the 20th century. Currently, there is no uniformity in the training and registration of specialized professionals, resulting in distinct scenarios. Considering the accessibility of scientific knowledge through technology and globalization, it is crucial to provide an objective overview of the current state of education in the field. This paper focuses on effective professional training as the primary subject of residency courses in this specialty. A proposal is presented for education, emphasizing the significance of providing quality professional training that is tailored to the specific legislation of each country.
文摘As people grow older, their cognitive functions undergo changes which may result in uncomfortable driving situations and even increase the risk of accidents. This research aims to understand the neuropsychological aspects of healthy aging and their possible relationship <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> changes in motor performance or ability. The research methodology is descriptive and includes a collection of basic studies in the scope of neuroscience, driving tasks, and older driver behavior. The final analysis points to certain changes in the functioning of the cerebral cortex and its connections as being responsible for poor performance in some basic driving tasks, but which can be compensated for by means of adapted mechanisms in motor vehicles. This study may contribute as a methodological tool, to the automobile design process, for the selection of Advanced Driver Assistance Systems (ADAS) or other emerging technologies which can compensate cognitive changes, improve safety, comfort and inclusion of older drivers in the future of automobile interior design. We conclude that in normal aging, people may present some cognitive deficits especially linked to the frontal and parietal lobe, which interfere with the necessary driving skills albeit not with the dangerous ones and can be compensated by technological solutions. The main innovation of this article is related to the bibliographical compilation and critical analysis in terms of identifying the neuropsychological aspects of normal human aging and car driving and its relationship with possible contributions from vehicular technology, as well its consider future trends in automotive interior design that should be analysed with caution in order to users inclusion.</span></span></span>
文摘This research aims to understand the psychological, the social and cognitive aspects of ageing and assess the relevance of driving a personal automobile to seniors. We know that biological ageing is an inescapable fact, but is there also a psychological and a cognitive ageing？ If so, is it related to getting older or to other factors？ How relevant is continuing to drive to seniors, and how can the activity influence psychological and cognitive types of their ageing and self well-being？ To answer these questions, we study several authors and concepts about mental health, development of ageing and their relationship to driving. We also explore psychological and cognitive changes associated with ageing, the principal behavioural changes of healthy senior people （with normal cognitive function） and MCI （mild cognitive impairment）, as well as how driving inhibition can induce and affect psychological and cognitive characteristics. We conclude that low mental functioning is caused by a set of biological, psychological and social factors, connected in turn to environmental factors. The slowdown of cognitive activities and performances in seniors is not inevitably accompanied by a decrease in intellectual capacity, low sensory acuity, or slowing psychomotor skills. Other factors should be considered--such as health status, limitations, anxiety, lack of interest, motivation and attitudes. The loss of cognitive abilities and the prevalence of mild cognitive impairment increase with age and are a growing concern, especially among seniors who drive cars. However, we still lack specific evidence based on tests and criteria--in particular, on psychological and cognitive domains--to assess senior drivers actually at risk. It is important to establish a base of evidence to allow objective risk determination. The safest senior drivers should continue driving for as long as possible, thereby contributing to their mental health, independence and quality of life.
文摘The main objective of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube （CFST） columns made with Rubberized Concrete （RuC）, and to assess the seismic performance of moment-resisting frames with these structural members. The paper describes an experimental campaign where a total of 36 specimens were tested, resorting to a novel testing setup, aimed at reducing both the preparation time and cost of the test specimens. Different geometrical and material parameters were considered, namely cross-section type, cross-section slenderness, aggregate replacement ratio, axial load level and lateral loading type. The members were tested under both monotonic and cyclic lateral loading, with different levels of applied axial loading. The test results show that the bending behaviour of CFST elements is highly dependent on the steel tube properties and that the type of infill does not have a significant influence on the flexural behaviour of the member. It is also found that Eurocode 4 is conservative in predicting the flexural capacity of the tested specimens. Additionally, it was found that the seismic design of composite moment- resisting frames with CFST columns, according to Eurocode 8, not only leads to lighter design solutions but also to enhanced seismic performance in comparison to steel frames.
基金Project supported by the National Natural Science Foundation of China(No.11971032)the Science and Technology Program of Guangzhou,China(No.201707010031)。
文摘A novel color image encryption algorithm based on dynamic deoxyribonucleic acid(DNA)encoding and chaos is presented.A three-neuron fractional-order discrete Hopfield neural network(FODHNN)is employed as a pseudo-random chaotic sequence generator.Its initial value is obtained with the secret key generated by a fiveparameter external key and a hash code of the plain image.The external key includes both the FODHNN discrete step size and order.The hash is computed with the SHA-2 function.This ensures a large secret key space and improves the algorithm sensitivity to the plain image.Furthermore,a new three-dimensional projection confusion method is proposed to scramble the pixels among red,green,and blue color components.DNA encoding and diffusion are used to diffuse the image information.Pseudo-random sequences generated by FODHNN are employed to determine the encoding rules for each pixel and to ensure the diversity of the encoding methods.Finally,confusion II and XOR are used to ensure the security of the encryption.Experimental results and the security analysis show that the proposed algorithm has better performance than those reported in the literature and can resist typical attacks.
