In this work,a novel one-time-programmable memory unit based on a Schottky-type p-GaN diode is proposed.During the programming process,the junction switches from a high-resistance state to a low-resistance state throu...In this work,a novel one-time-programmable memory unit based on a Schottky-type p-GaN diode is proposed.During the programming process,the junction switches from a high-resistance state to a low-resistance state through Schottky junction breakdown,and the state is permanently preserved.The memory unit features a current ratio of more than 10^(3),a read voltage window of 6 V,a programming time of less than 10^(−4)s,a stability of more than 108 read cycles,and a lifetime of far more than 10 years.Besides,the fabrication of the device is fully compatible with commercial Si-based GaN process platforms,which is of great significance for the realization of low-cost read-only memory in all-GaN integration.展开更多
Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apica...Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apical periodontitis with sinus tract in the deciduous teeth treated in our hospital from January 2022 to December 2023 were selected and grouped by the randomized numerical table method,with 54 cases in the experimental group and 55 cases in the control group.The experimental group was treated with one-time endodontics and the control group was treated with conventional endodontics.Results:After the treatment,the total effective rate of treatment was higher in the experimental group than in the control group(P<0.05);the incidence of adverse events was lower in the experimental group than in the control group(P<0.05);the satisfaction of the children's family members was higher in the experimental group than in the control group(P<0.05);the pain duration was lower in the experimental group than in the control group(P<0.05).Conclusion:In the experimental group,children with chronic apical periodontitis with sinus tract of the deciduous teeth were given one-time endodontic treatment,and the results of its implementation were relatively good.展开更多
Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization ...Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization with one-time application at the first bloom stage without lint yield reduction.However,it has been hypothesized that one-time fertilization at an earlier growth stage could be a more effective and economic management practice.A two-year field experiment was conducted by applying five fertilizer one-time fertilization at 0(FT1),5(FT2),10(FT3),15(FT4),and 20(FT5)days after the first flower appeared in the field and one three-split fertilizer application taken as the conventional control(FT6),making six treatments altogether.Cotton growth period,biomass accumulation,yield,and its formation were quantified.The results showed that the one-time fertilization did not affect the cotton growth progress as compared to FT6,however,the total crop cycles for FT3–FT5 were 3 days shorter.FT1 produced the highest cotton lint yield(1396 kg ha–1),which was similar to the FT6 but higher than the other treatments,and could be attributed to more bolls per unit area and higher lint percentage.Cotton yield was positively correlated with cotton plant biomass accumulated.FT1 had both the highest average(VT)(193.7 kg ha–1 d–1)and the highest maximum(VM)(220.9 kg ha–1 d–1)rates during the fast biomass accumulation period.These results suggest that one-time fertilizer application at the first flower stage might be an adjustment that is more effective than at first bloom,and allowed for easier decision making for application date due to non counting of plants with flowers is needed.展开更多
To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architectu...To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architecture via one-time sintering process. The modified structural materials as lithium-ion cathodes present good structural stability and superior cycle performance in LIBs. The discharge capacity of the ZrO2-coated and Zr-doped hollow pristine is 220 mAh g-1 at the 20th cycle at 0.2 C(discharge capacity loss, 2.7%)and 150 m Ah g-1 at the 100 th cycle at 1 C(discharge capacity loss, 17.7%), respectively. However, hollow pristine electrode only delivers 203 m Ah g-1 at the 20 th cycle at 0.2 C and 124 mAh g-1 at the 100 th cycle at 1 C, respectively, and the corresponding to capacity retention is 92.2% and 72.8%, respectively.Diffusion coefficients of modified hollow pristine electrode are much higher than that of hollow pristine electrode after 100 cycles(approach to 1.4 times). In addition, we simulate the adsorption reaction of HF on the surface of ZrO2-coated layer by the first-principles theory. The calculations prove that the adsorption energy of HF on the surface of ZrO2-coated layer is about-1.699 e V, and the ZrO2-coated layer could protect the hollow spherical xLi2MnO3·(1–x)LiMO2 from erosion by HF. Our results would be applicable for systematic amelioration of high-performance lithium rich material for anode with the respect of practical application.展开更多
We ayptanalyze Kim et. al's one-time proxy signature scheme used in mobileagents, and then a successful forgery is introduced It is showed that a dishonest customer cansuccessfully forge a valid one-time proxy sig...We ayptanalyze Kim et. al's one-time proxy signature scheme used in mobileagents, and then a successful forgery is introduced It is showed that a dishonest customer cansuccessfully forge a valid one-time proxy signature by impersonating the stiver Furthermore, he canrequest the server with responsibility for the forged bidding information.展开更多
A 32 kbit OTP(one-time programmable)memory for MCUs(micro-controller units)used in remote controllers was designed.This OTP memory is used for program and data storage.It is required to apply 5.5V to BL(bit-line)and 1...A 32 kbit OTP(one-time programmable)memory for MCUs(micro-controller units)used in remote controllers was designed.This OTP memory is used for program and data storage.It is required to apply 5.5V to BL(bit-line)and 11V to WL(word-line)for a OTP cell of 0.35μm ETOX(EEPROM tunnel oxide)type by MagnaChip.We use 5V transistors on column data paths to reduce the area of column data paths since they require small areas.In addition,we secure device reliability by using HV(high-voltage)transistors in the WL driver.Furthermore,we change from a static logic to a dynamic logic used for the WL driver in the core circuit.Also,we optimize the WD(write data)switch circuit.Thus,we can implement them with a small-area design.In addition,we implement the address predecoder with a small-area logic circuit.The area of the designed 32 kbit OTP with 5V and HV devices is 674.725μm×258.75μm(=0.1745mm2)and is 56.3% smaller than that using 3.3V devices.展开更多
Lightweight roof greening is an important way for improving urban ecological environment and has good ecological and social benefits, but the investment is- too-high for the investors. Therefore, it is necessary to im...Lightweight roof greening is an important way for improving urban ecological environment and has good ecological and social benefits, but the investment is- too-high for the investors. Therefore, it is necessary to improve the system of lightweight roof greening. This study introduced a lightweight roof greening mode with low cost, simple construction, rapid formation, good economic benefit and convenient curing.展开更多
Glass ceramics was made by the one-time sintering method using the main raw material of iron tailings. On the basis of quaternary system of CaO-MgO-Al2O3-SiO2, using DTA, XRD and SEM, the effects of different nucleati...Glass ceramics was made by the one-time sintering method using the main raw material of iron tailings. On the basis of quaternary system of CaO-MgO-Al2O3-SiO2, using DTA, XRD and SEM, the effects of different nucleating agents and mixing amounts as well as heat treatment on the crystallization of railings glass ceramics were studied. The experimental results show that, nucleating agent and heat treatment are two necessary conditions for one-time sintering preparation of tailings glass ceramics namely, only adding nucleating agent or experiencing heat treatment, the quaternary system can not crystallize. The composite nucleating agent consisting of Cr2O3 and TiO2 can further lead to the crystallization of the CaO-MgO-A1203-SiO2 quaternary system at the lower temperature, with the major phase of diopside. In the range of mass content, 0%-4%, crystal intensity and crystal content grow. But when mass content is more than 4%, the crystal size will become coarser and the crystal distribution will be less regular. Different heat treatment regimes do not change the composition of the crystalline major phase in the glass ceramics crystallization of CaO-MgO-Al2O3-SiO2 system. In the range of 30-60 minutes, with the extension of nucleation and crystallization, crystallization degree enhanced, but if the holding time surpasses 60 minutes, the crystallization is worse.展开更多
The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random k...The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random keys for OTP.In this paper,we propose a joint SKG and OTP encryption scheme with the aid of a reconfigurable intelligent surface(RIS)to boost secret key rate.To maximize the efficiency of secure communication,we divide the process of secure transmission into two stages:SKG and then encrypted packet transmission.Meanwhile,we design an optimal algorithm for allocating time slots for SKG to maximize SKG efficiency without security risk.Furthermore,we design a key updating protocol based on our SKG scheme for OTP encryption.Simulation results verify that our scheme can generate keys securely and efficiently,and significantly improve the secure communication performance in an intelligent IoT system.展开更多
The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Base...The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Based on the analysis of road drainage requirements,traditional paving materials have relatively poor water permeability,which leads to ponding problems during road use[1].Within this frame of reference,beginning with the characteristics of permeable paving materials,this paper makes an in-depth exploration on practical application measures.展开更多
Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and i...Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and its properties are influenced by the crude oil source and refining process,resulting in a significant carbon footprint.With growing awareness of resource depletion and environmental concerns,pavement researchers are exploring sustainable alternatives to reduce dependence on fossil sources.This includes a rising trend in using renewable materials like biomasses to produce bio-based binders as substitutes for bitumen,aiming for a more sustainable approach.Biomasses,including vegetal and animal wastes,and waste cooking oils,as substitutes for crude oil in the production of bio-binders.Through thermochemical conversion(TCC),such as pyrolysis,biomasses can be converted into bio-char and bio-oils,which can replace fossil-based components in binders.Researchers have utilized these bio-products to reduce the dependency on fossil fuels in binders.However,there are no set minimum requirements for bio-components in bio-based binders.As the percentage of replaced bitumen increases,various types of binders are produced,including modified bitumen,extended bitumen,and alternative binders,where the fossil replacement is gradual.Overall rheological tests on bio-binders,reveal that those containing biochar exhibit increased viscosity,stiffness,rutting resistance,and sometimes antioxidant properties.Conversely,bio-binders with bio-oils as bitumen substitutes show poorer performance at high temperatures but improved behavior at low temperatures.These results suggest that bio-binders could provide versatile solutions for various climatic and loading conditions in road construction.However,the development of pavement mixtures based on bio-binders has not been studied in depth and requires further attention to unlock its full potential.As sustainability considerations,including life cycle assessments(LCA)and life cycle cost analyses(LCC),are crucial aspects for future studies.It is essential not only to collect data on the performance characteristics of bio-binders but also to understand their environmental impact and recyclability.In-depth evaluations using methods such as LCA and LCC will provide valuable insights into the overall sustainability and long-term viability of these products.展开更多
Tactile paving is a professional road facility to ensure the safe travel of people with visual impairment.However,there are many problems with tactile paving travel in practice.For one,some tactile paving is seriously...Tactile paving is a professional road facility to ensure the safe travel of people with visual impairment.However,there are many problems with tactile paving travel in practice.For one,some tactile paving is seriously damaged,and the other is the accumulation of obstacles.How to help visually impaired people recognize and locate obstacles in tactile paving is a problem worth studying.In this paper,image recognition technology is used to recognize the tactile paving pictures with obstacles,and an attention mechanism is used to optimize samples to improve recognition accuracy.展开更多
The important parameters that influence the mechanical property of the pavinglayer on an orthotropic steel bridge deck are the paving layer thickness and modulus of the asphaltconcrete surfacing. Three important indic...The important parameters that influence the mechanical property of the pavinglayer on an orthotropic steel bridge deck are the paving layer thickness and modulus of the asphaltconcrete surfacing. Three important indices that control the typical failures of the paving layerare the maximum tensile stress of paving layer, the maximum shear stress between the steel deck andthe paving layer, and the maximum deflection on the paving surface. In this paper, the analyticalmodel of paving systems on orthotropic steel bridge deck is established, and the finite elementmethod is adopted to study the stress and strain of paving system. With the variation of asphaltconcrete modulus in high or low temperature season, the influences of paving layer thickness onthree control indices are researched. The results provide a theoretical basis for the determinationof thickness of the paving layer on the steel bridge deck.展开更多
Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic...Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic crude oil is unfit for the production of highway paving asphalts directly, Neither are the de-oiled asphalts of the YVR. In this research a blending method and an optimal process of solvent de-asphalts are adopted to investigate the feasibility of formulating highway-paving asphalts from YVR. Results show that highway paving asphalts are formulated by blending solvent de-oiled asphalts with one or more of the materials including YVR, decanted oil from FCC process, and furfural extracts from lubricating base stocks. Further investigations indicate that adding oil decanted from FCC process to the solvent de-asphalting process can increase the de-asphalted oil production, improve the de-oiled asphalts quality, and thus optimize the refinery processes. The methodology of this research can be extended even to refineries processing non-paraffinic crude oils.展开更多
The paving segregation of asphalt mixture was closely related to the structure size and using parameters for the screw distributor of paver,and the paving uniformity of the mixture was determined by the screw blade di...The paving segregation of asphalt mixture was closely related to the structure size and using parameters for the screw distributor of paver,and the paving uniformity of the mixture was determined by the screw blade diameter,pitch,and the position of the mixture in the screw distributor.Through researching the kinematics of the mixture in the screw distributor,the mathematical model was established,and the mathematical model was related with structural parameters,used parameters and material parameters.Through the mathematical model,the various parameters on the screw distributor job performance were analyzed,and the unstable area,meta-stable area and stable area were determined.In the project,the full-scale test in actual project was conducted by using the AC25 mixture.By changing the using parameters compare the paving operations,the results show that,the reasonable parameter will greatly improve the uniformity of paving,and the surface proportion of structural depth of mixture decrease from the 2.13 to 1.60.展开更多
The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely ...The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely different materials: a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt con- crete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.展开更多
Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like...Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like the Middle East and this paper presents the design and construction challenges posed while assessing damaged concrete runway in empty quarter of Saudi Arabia. <span style="font-family:Verdana;">A number of design options for repairs for runway pavement were consi</span><span style="font-family:Verdana;">dered and rubblization was chosen as a preferred option for repair. This paper includes the consideration for the assessment and adoption of the concrete rubblized modulus value using the falling weight deflectometer, optimization </span><span style="font-family:Verdana;">of the tests for the whole runway using the Heavy Weight Deflectometer</span><span style="font-family:Verdana;"> HWD testing to replace pits, safely working around the utilities, reasonable assumption of drop height of the pavement and installation of utility conduits in the rubblized layer. Findings of the paper demonstrates resolving</span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">technical issues which are not very well covered in the Federal Aviation Authority (FAA) EB-66 such as the additional test strips, minimum areas of rubblization for assessment using test pits, drop in the height of concrete surface and fixing of utilities in rubblized pavement. The case study demonstrates that the rubblization can be successfully carried out in remote locations like empty quarter of Saudi Arabia with carefully carried out detailed site investigations, adopt</span><span style="font-family:Verdana;">ing correct assumed design rubblization modulus, quality control using </span><span style="font-family:Verdana;">HWD, protection of utilities while rubblizing and use of polymer modified asphalt for successful project deployment.</span></span></span></span>展开更多
In order to enlarge the use of coal tar pitch(CTP) in paving road,CTP and 60th paving pitch (PP) were extracted by n-heptane,toluene and ethanol step by step in a Soxhlet apparatus.The three fractions of CTP and PP we...In order to enlarge the use of coal tar pitch(CTP) in paving road,CTP and 60th paving pitch (PP) were extracted by n-heptane,toluene and ethanol step by step in a Soxhlet apparatus.The three fractions of CTP and PP were detected using UV-absorption(UV-A),elemental analyses(EA) and nuclear magnetic resonance(NMR) firstly as a whole unit after quality characterization of physical nature of CTP and PP were finished.The CTP had more saturate aliphatic and residue compounds dissolved in ethanol.On the other hand there were more continental type structures of aromatic ring than that of PP.There was almost no residue in PP after extracted by ethanol.The results explained why CTP was crisp in cold winter and was soften in summer.The following research will focus on how to change the chemical construction of CTP into the relative similar structures with those of PP through adding polymer.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant 2022YFB3604400in part by the Youth Innovation Promotion Association of Chinese Academy Sciences (CAS)+4 种基金in part by the CAS-Croucher Funding Scheme under Grant CAS22801in part by National Natural Science Foundation of China under Grant 62334012, Grant 62074161, Grant 62004213, Grant U20A20208, and Grant 62304252in part by the Beijing Municipal Science and Technology Commission project under Grant Z201100008420009 and Grant Z211100007921018in part by the University of CASin part by the IMECAS-HKUST-Joint Laboratory of Microelectronics
文摘In this work,a novel one-time-programmable memory unit based on a Schottky-type p-GaN diode is proposed.During the programming process,the junction switches from a high-resistance state to a low-resistance state through Schottky junction breakdown,and the state is permanently preserved.The memory unit features a current ratio of more than 10^(3),a read voltage window of 6 V,a programming time of less than 10^(−4)s,a stability of more than 108 read cycles,and a lifetime of far more than 10 years.Besides,the fabrication of the device is fully compatible with commercial Si-based GaN process platforms,which is of great significance for the realization of low-cost read-only memory in all-GaN integration.
文摘Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apical periodontitis with sinus tract in the deciduous teeth treated in our hospital from January 2022 to December 2023 were selected and grouped by the randomized numerical table method,with 54 cases in the experimental group and 55 cases in the control group.The experimental group was treated with one-time endodontics and the control group was treated with conventional endodontics.Results:After the treatment,the total effective rate of treatment was higher in the experimental group than in the control group(P<0.05);the incidence of adverse events was lower in the experimental group than in the control group(P<0.05);the satisfaction of the children's family members was higher in the experimental group than in the control group(P<0.05);the pain duration was lower in the experimental group than in the control group(P<0.05).Conclusion:In the experimental group,children with chronic apical periodontitis with sinus tract of the deciduous teeth were given one-time endodontic treatment,and the results of its implementation were relatively good.
基金supported by the National Natural Science Foundation of China (31271665)the Pairing Program of Key Laboratory of Oasis Ecology Agriculture, Xinjiang Production and Construction Group with Eminent Scholars in Elite Universities, China (201601)
文摘Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization with one-time application at the first bloom stage without lint yield reduction.However,it has been hypothesized that one-time fertilization at an earlier growth stage could be a more effective and economic management practice.A two-year field experiment was conducted by applying five fertilizer one-time fertilization at 0(FT1),5(FT2),10(FT3),15(FT4),and 20(FT5)days after the first flower appeared in the field and one three-split fertilizer application taken as the conventional control(FT6),making six treatments altogether.Cotton growth period,biomass accumulation,yield,and its formation were quantified.The results showed that the one-time fertilization did not affect the cotton growth progress as compared to FT6,however,the total crop cycles for FT3–FT5 were 3 days shorter.FT1 produced the highest cotton lint yield(1396 kg ha–1),which was similar to the FT6 but higher than the other treatments,and could be attributed to more bolls per unit area and higher lint percentage.Cotton yield was positively correlated with cotton plant biomass accumulated.FT1 had both the highest average(VT)(193.7 kg ha–1 d–1)and the highest maximum(VM)(220.9 kg ha–1 d–1)rates during the fast biomass accumulation period.These results suggest that one-time fertilizer application at the first flower stage might be an adjustment that is more effective than at first bloom,and allowed for easier decision making for application date due to non counting of plants with flowers is needed.
基金the financial support by the Natural Science Foundation of Guangdong Province(2019A1515012111)the National Natural Science Foundation of China(51804199 and 51604081)+2 种基金the Science and Technology Innovation Commission of Shenzhen(JCYJ20190808173815205 and 20180123)the Shenzhen Science and Technology Program(KQTD20180412181422399)“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(16CG40)。
文摘To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architecture via one-time sintering process. The modified structural materials as lithium-ion cathodes present good structural stability and superior cycle performance in LIBs. The discharge capacity of the ZrO2-coated and Zr-doped hollow pristine is 220 mAh g-1 at the 20th cycle at 0.2 C(discharge capacity loss, 2.7%)and 150 m Ah g-1 at the 100 th cycle at 1 C(discharge capacity loss, 17.7%), respectively. However, hollow pristine electrode only delivers 203 m Ah g-1 at the 20 th cycle at 0.2 C and 124 mAh g-1 at the 100 th cycle at 1 C, respectively, and the corresponding to capacity retention is 92.2% and 72.8%, respectively.Diffusion coefficients of modified hollow pristine electrode are much higher than that of hollow pristine electrode after 100 cycles(approach to 1.4 times). In addition, we simulate the adsorption reaction of HF on the surface of ZrO2-coated layer by the first-principles theory. The calculations prove that the adsorption energy of HF on the surface of ZrO2-coated layer is about-1.699 e V, and the ZrO2-coated layer could protect the hollow spherical xLi2MnO3·(1–x)LiMO2 from erosion by HF. Our results would be applicable for systematic amelioration of high-performance lithium rich material for anode with the respect of practical application.
文摘We ayptanalyze Kim et. al's one-time proxy signature scheme used in mobileagents, and then a successful forgery is introduced It is showed that a dishonest customer cansuccessfully forge a valid one-time proxy signature by impersonating the stiver Furthermore, he canrequest the server with responsibility for the forged bidding information.
基金Project supported by the Second Stage of Brain Korea 21 Projects,Korea
文摘A 32 kbit OTP(one-time programmable)memory for MCUs(micro-controller units)used in remote controllers was designed.This OTP memory is used for program and data storage.It is required to apply 5.5V to BL(bit-line)and 11V to WL(word-line)for a OTP cell of 0.35μm ETOX(EEPROM tunnel oxide)type by MagnaChip.We use 5V transistors on column data paths to reduce the area of column data paths since they require small areas.In addition,we secure device reliability by using HV(high-voltage)transistors in the WL driver.Furthermore,we change from a static logic to a dynamic logic used for the WL driver in the core circuit.Also,we optimize the WD(write data)switch circuit.Thus,we can implement them with a small-area design.In addition,we implement the address predecoder with a small-area logic circuit.The area of the designed 32 kbit OTP with 5V and HV devices is 674.725μm×258.75μm(=0.1745mm2)and is 56.3% smaller than that using 3.3V devices.
基金Supported by Science and Technology Planning Project of Guangdong Province,China(No.2015B090904008)Soft Science Planning Project of Guangdong Province(2014B090903015)Ecological Environment Construction and Protection(Techand)Engineering and Technological Research Center(YKHZZ[2013]1589)~~
文摘Lightweight roof greening is an important way for improving urban ecological environment and has good ecological and social benefits, but the investment is- too-high for the investors. Therefore, it is necessary to improve the system of lightweight roof greening. This study introduced a lightweight roof greening mode with low cost, simple construction, rapid formation, good economic benefit and convenient curing.
基金Funded by The National Key Technology R & D Program of China for the 11th Five-Year Plan(2006BAJ04A04)
文摘Glass ceramics was made by the one-time sintering method using the main raw material of iron tailings. On the basis of quaternary system of CaO-MgO-Al2O3-SiO2, using DTA, XRD and SEM, the effects of different nucleating agents and mixing amounts as well as heat treatment on the crystallization of railings glass ceramics were studied. The experimental results show that, nucleating agent and heat treatment are two necessary conditions for one-time sintering preparation of tailings glass ceramics namely, only adding nucleating agent or experiencing heat treatment, the quaternary system can not crystallize. The composite nucleating agent consisting of Cr2O3 and TiO2 can further lead to the crystallization of the CaO-MgO-A1203-SiO2 quaternary system at the lower temperature, with the major phase of diopside. In the range of mass content, 0%-4%, crystal intensity and crystal content grow. But when mass content is more than 4%, the crystal size will become coarser and the crystal distribution will be less regular. Different heat treatment regimes do not change the composition of the crystalline major phase in the glass ceramics crystallization of CaO-MgO-Al2O3-SiO2 system. In the range of 30-60 minutes, with the extension of nucleation and crystallization, crystallization degree enhanced, but if the holding time surpasses 60 minutes, the crystallization is worse.
基金supported by National key research and development program of China, Joint research of IoT security system and key technologies based on quantum key (2020YFE0200600)
文摘The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random keys for OTP.In this paper,we propose a joint SKG and OTP encryption scheme with the aid of a reconfigurable intelligent surface(RIS)to boost secret key rate.To maximize the efficiency of secure communication,we divide the process of secure transmission into two stages:SKG and then encrypted packet transmission.Meanwhile,we design an optimal algorithm for allocating time slots for SKG to maximize SKG efficiency without security risk.Furthermore,we design a key updating protocol based on our SKG scheme for OTP encryption.Simulation results verify that our scheme can generate keys securely and efficiently,and significantly improve the secure communication performance in an intelligent IoT system.
文摘The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Based on the analysis of road drainage requirements,traditional paving materials have relatively poor water permeability,which leads to ponding problems during road use[1].Within this frame of reference,beginning with the characteristics of permeable paving materials,this paper makes an in-depth exploration on practical application measures.
基金The research is funded by the NEXT GENERATION EU–PNRR project ex D.M.352/2022.The authors would like to thank ENI S.p.A for supporting this research.
文摘Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and its properties are influenced by the crude oil source and refining process,resulting in a significant carbon footprint.With growing awareness of resource depletion and environmental concerns,pavement researchers are exploring sustainable alternatives to reduce dependence on fossil sources.This includes a rising trend in using renewable materials like biomasses to produce bio-based binders as substitutes for bitumen,aiming for a more sustainable approach.Biomasses,including vegetal and animal wastes,and waste cooking oils,as substitutes for crude oil in the production of bio-binders.Through thermochemical conversion(TCC),such as pyrolysis,biomasses can be converted into bio-char and bio-oils,which can replace fossil-based components in binders.Researchers have utilized these bio-products to reduce the dependency on fossil fuels in binders.However,there are no set minimum requirements for bio-components in bio-based binders.As the percentage of replaced bitumen increases,various types of binders are produced,including modified bitumen,extended bitumen,and alternative binders,where the fossil replacement is gradual.Overall rheological tests on bio-binders,reveal that those containing biochar exhibit increased viscosity,stiffness,rutting resistance,and sometimes antioxidant properties.Conversely,bio-binders with bio-oils as bitumen substitutes show poorer performance at high temperatures but improved behavior at low temperatures.These results suggest that bio-binders could provide versatile solutions for various climatic and loading conditions in road construction.However,the development of pavement mixtures based on bio-binders has not been studied in depth and requires further attention to unlock its full potential.As sustainability considerations,including life cycle assessments(LCA)and life cycle cost analyses(LCC),are crucial aspects for future studies.It is essential not only to collect data on the performance characteristics of bio-binders but also to understand their environmental impact and recyclability.In-depth evaluations using methods such as LCA and LCC will provide valuable insights into the overall sustainability and long-term viability of these products.
基金supported by the Jiangsu Province College Student Innovation Training Program(Project No.20221127684Y)the Talent Startup project of Nanjing Institute of Technology(Project No.YKJ202117)。
文摘Tactile paving is a professional road facility to ensure the safe travel of people with visual impairment.However,there are many problems with tactile paving travel in practice.For one,some tactile paving is seriously damaged,and the other is the accumulation of obstacles.How to help visually impaired people recognize and locate obstacles in tactile paving is a problem worth studying.In this paper,image recognition technology is used to recognize the tactile paving pictures with obstacles,and an attention mechanism is used to optimize samples to improve recognition accuracy.
文摘The important parameters that influence the mechanical property of the pavinglayer on an orthotropic steel bridge deck are the paving layer thickness and modulus of the asphaltconcrete surfacing. Three important indices that control the typical failures of the paving layerare the maximum tensile stress of paving layer, the maximum shear stress between the steel deck andthe paving layer, and the maximum deflection on the paving surface. In this paper, the analyticalmodel of paving systems on orthotropic steel bridge deck is established, and the finite elementmethod is adopted to study the stress and strain of paving system. With the variation of asphaltconcrete modulus in high or low temperature season, the influences of paving layer thickness onthree control indices are researched. The results provide a theoretical basis for the determinationof thickness of the paving layer on the steel bridge deck.
文摘Many specifications of paving asphalts are closely related to their colloidal stability, which is, however, determined by their exact chemical compositions. The Yumen vacuum residue (YVR), the bottoms of a paraffinic crude oil is unfit for the production of highway paving asphalts directly, Neither are the de-oiled asphalts of the YVR. In this research a blending method and an optimal process of solvent de-asphalts are adopted to investigate the feasibility of formulating highway-paving asphalts from YVR. Results show that highway paving asphalts are formulated by blending solvent de-oiled asphalts with one or more of the materials including YVR, decanted oil from FCC process, and furfural extracts from lubricating base stocks. Further investigations indicate that adding oil decanted from FCC process to the solvent de-asphalting process can increase the de-asphalted oil production, improve the de-oiled asphalts quality, and thus optimize the refinery processes. The methodology of this research can be extended even to refineries processing non-paraffinic crude oils.
基金Funded by the Special Fund for Basic Scientific Research of Central Colleges,Chang'an University and Basic Research Support Program of Chang'an University(CHD2011SY005)
文摘The paving segregation of asphalt mixture was closely related to the structure size and using parameters for the screw distributor of paver,and the paving uniformity of the mixture was determined by the screw blade diameter,pitch,and the position of the mixture in the screw distributor.Through researching the kinematics of the mixture in the screw distributor,the mathematical model was established,and the mathematical model was related with structural parameters,used parameters and material parameters.Through the mathematical model,the various parameters on the screw distributor job performance were analyzed,and the unstable area,meta-stable area and stable area were determined.In the project,the full-scale test in actual project was conducted by using the AC25 mixture.By changing the using parameters compare the paving operations,the results show that,the reasonable parameter will greatly improve the uniformity of paving,and the surface proportion of structural depth of mixture decrease from the 2.13 to 1.60.
基金Project BK2005020 supported by the Natural Science Foundation of the Jiangsu Province
文摘The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely different materials: a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt con- crete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.
文摘Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like the Middle East and this paper presents the design and construction challenges posed while assessing damaged concrete runway in empty quarter of Saudi Arabia. <span style="font-family:Verdana;">A number of design options for repairs for runway pavement were consi</span><span style="font-family:Verdana;">dered and rubblization was chosen as a preferred option for repair. This paper includes the consideration for the assessment and adoption of the concrete rubblized modulus value using the falling weight deflectometer, optimization </span><span style="font-family:Verdana;">of the tests for the whole runway using the Heavy Weight Deflectometer</span><span style="font-family:Verdana;"> HWD testing to replace pits, safely working around the utilities, reasonable assumption of drop height of the pavement and installation of utility conduits in the rubblized layer. Findings of the paper demonstrates resolving</span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">technical issues which are not very well covered in the Federal Aviation Authority (FAA) EB-66 such as the additional test strips, minimum areas of rubblization for assessment using test pits, drop in the height of concrete surface and fixing of utilities in rubblized pavement. The case study demonstrates that the rubblization can be successfully carried out in remote locations like empty quarter of Saudi Arabia with carefully carried out detailed site investigations, adopt</span><span style="font-family:Verdana;">ing correct assumed design rubblization modulus, quality control using </span><span style="font-family:Verdana;">HWD, protection of utilities while rubblizing and use of polymer modified asphalt for successful project deployment.</span></span></span></span>
基金Supported by the Progress Plan of Science & Technology of Wuhan Pingmei Wugang Unite Coking Chemical Corp.Ltd,Ltd.of WISCO(2008Z012)
文摘In order to enlarge the use of coal tar pitch(CTP) in paving road,CTP and 60th paving pitch (PP) were extracted by n-heptane,toluene and ethanol step by step in a Soxhlet apparatus.The three fractions of CTP and PP were detected using UV-absorption(UV-A),elemental analyses(EA) and nuclear magnetic resonance(NMR) firstly as a whole unit after quality characterization of physical nature of CTP and PP were finished.The CTP had more saturate aliphatic and residue compounds dissolved in ethanol.On the other hand there were more continental type structures of aromatic ring than that of PP.There was almost no residue in PP after extracted by ethanol.The results explained why CTP was crisp in cold winter and was soften in summer.The following research will focus on how to change the chemical construction of CTP into the relative similar structures with those of PP through adding polymer.