As energy efficiency is one of the key essentials towards sustainability, the development of an energy-resource efficient manufacturing system is among the great challenges facing the current industry. Meanwhile, the ...As energy efficiency is one of the key essentials towards sustainability, the development of an energy-resource efficient manufacturing system is among the great challenges facing the current industry. Meanwhile, the availability of advanced technological innovation has created more complex manufacturing systems that involve a large variety of processes and machines serving different functions. To extend the limited knowledge on energy-efficient scheduling, the research presented in this paper attempts to model the production schedule at an operation process by considering the balance of energy consumption reduction in production, production work flow （productivity） and quality. An innovative systematic approach to manufacturing energy-resource efficiency is proposed with the virtual simulation as a predictive modelling enabler, which provides real-time manufacturing monitoring, virtual displays and decision-makings and consequentially an analytical and multidimensional correlation analysis on interdependent relationships among energy consumption, work flow and quality errors. The regression analysis results demonstrate positive relationships between the work flow and quality errors and the work flow and energy consumption. When production scheduling is controlled through optimization of work flow, quality errors and overall energy consumption, the energy-resource efficiency can be achieved in the production. Together, this proposed multidimensional modelling and analysis approach provides optimal conditions for the production scheduling at the manufacturing system by taking account of production quality, energy consumption and resource efficiency, which can lead to the key competitive advantages and sustainability of the system operations in the industry.展开更多
The most significant characteristic in frequency domain during cutting chatter occurring process is the steep rise of the vibration energy in certain narrow frequency band containing the chatter frequency. In accordan...The most significant characteristic in frequency domain during cutting chatter occurring process is the steep rise of the vibration energy in certain narrow frequency band containing the chatter frequency. In accordance with the frequency band-energy principle, a reliable criterion for chatter judgement is proposed and the in-process detection of cutting chatter is realized by the use of microcomputer. This method has the advantages of rapidity, high sensitivity, accuracy and high resistance to interference. Some concrete measures taken in practical applications are also discussed.展开更多
A line-shaped beam is useful for increasing the processing speed in laser grooving and scribing.In laser grooving,depth control of the processed structure is important for performing precise processing.In this paper,i...A line-shaped beam is useful for increasing the processing speed in laser grooving and scribing.In laser grooving,depth control of the processed structure is important for performing precise processing.In this paper,in-process monitoring of the depth of a structure formed by femtosecond laser processing with a line-shaped beam using swept-source optical coherence tomography(SS-OCT)was demonstrated.In the evaluation of the SS-OCT system,the depth resolution,measurement accuracy,and axial measurable range were 15.8μm,±2.5μm and 5.3 mm,respectively.In laser grooving,the structural shape and the distribution of deposited debris were successfully monitored.The measured depth agreed well with the depth obtained using a laser confocal microscope.The proposed method will be effective for precise laser processing with feedback control of the laser parameters based on in-process monitoring of the processed structure.展开更多
In recent years many security attacks occur when malicious codes abuse in-process memory resources.Due to the increasing complexity,an application program may call third-party code which cannot be controlled by progra...In recent years many security attacks occur when malicious codes abuse in-process memory resources.Due to the increasing complexity,an application program may call third-party code which cannot be controlled by programmers but may contain security vulnerabilities.As a result,the users have the risk of suffering information leakage and control flow hijacking.However,current solutions like Intel memory protection extensions(MPX)severely degrade performance,while other approaches like Intel memory protection keys(MPK)lack flexibility in dividing security domains.In this paper,we propose IMPULP,an effective and efficient hardware approach for in-process memory protection.The rationale of IMPULP is user-level partitioning that user code segments are divided into different security domains according to their instruction addresses,and accessible memory spaces are specified dynamically for each domain via a set of boundary registers.Each instruction related to memory access will be checked according to its security domain and the corresponding boundaries,and illegal in-process memory access of untrusted code segments will be prevented.IMPULP can be leveraged to prevent a wide range of in-process memory abuse attacks,such as buffer overflows and memory leakages.For verification,an FPGA prototype based on RISC-V instruction set architecture has been developed.We present eight tests to verify the effectiveness of IMPULP,including five memory protection function tests,a test to defense typical buffer overflow,a test to defense famous memory leakage attack named Heartbleed,and a test for security benchmark.We execute the SPEC CPU2006 benchmark programs to evaluate the efficiency of IMPULP.The performance overhead of IMPULP is less than 0.2%runtime on average,which is negligible.Moreover,the resource overhead is less than 5.5%for hardware modification of IMPULP.展开更多
In this paper,we propose an in-process measurement method of the diameter of micro-optical fiber such as a tapered optical fiber.The proposed technique is based on analyzing optically scattered light generated by stan...In this paper,we propose an in-process measurement method of the diameter of micro-optical fiber such as a tapered optical fiber.The proposed technique is based on analyzing optically scattered light generated by standing wave illumination.The proposed method is significant in that it requires an only limited measurement range and does not require a high dynamic range sensor.These properties are suitable for in-process measurement.This experiment verified that the proposed method could measure a fiber diameter as stable as±0.01μm under an air turbulence environment.As a result of comparing the measured diameter distribution with those by scanning electron microscopy,it was confirmed that the proposed method has a measurement accuracy better than several hundred nanometers.展开更多
The constructing method of a simulation system is discussed in this paper. It is for a Decision Support System (DSS) of main in-process warehouse on a large scale flexible production line. This system is decomposed in...The constructing method of a simulation system is discussed in this paper. It is for a Decision Support System (DSS) of main in-process warehouse on a large scale flexible production line. This system is decomposed into three function blocks: DSS, support environment for simulation, simulating dispatch module. It has a fine structure and works coordinatively to complete whatever assignment for simulation tasks of a complicated production system.展开更多
UNITANK is a biological wastewater treatment process that combines the advantages of traditional activated sludge process and sequencing batch reactor, which is divided into Tank A, B and C. In this study, the sludge ...UNITANK is a biological wastewater treatment process that combines the advantages of traditional activated sludge process and sequencing batch reactor, which is divided into Tank A, B and C. In this study, the sludge distribution and its impact on performance of UNITANK were carried out in Liede Wastewater Plant （WWTP） of Guangzhou, China. Results showed that there was a strong affiliation between Tank A and B of the system in sludge concentration distribution. The initial sludge concentration in Tank A could present the sludge distribution of the whole system. The sludge distribution was mainly influenced by hydraulic condition. Unsteady sludge distribution had an impact on variations of substrates in reactors, especially in decisive reactor, and this could lead to failure of system. Settler could partially remove substrates such as COD and NO3-N, but there was adventure of sludge deterioration. The rational initial sludge concentration in Tank A should be 4000-6000 mg/L MLSS.展开更多
A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel sl...A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel slag before air quenching can more effectively improve the slag's grindability than milltailings, which is the other modification agent tested under the same conditions. The role of fly ash is strengthened as its proportion increases, although the degree of promotion is gradually reduced. As a result of the reaction between fly ash and steel slag at high temperature, some new mineral phases and vitreous bodies with fine grindability promote the slag grinding easily. This work is helpful to making a comprehensive utilization of steel slag and maximize its economic efficiency in China.展开更多
The in-process changes of weld nugget growth during the Resistance Spot Welding were investigated based on the resistance of input electrical impedance. To compute the time varying resistance of input electrical imped...The in-process changes of weld nugget growth during the Resistance Spot Welding were investigated based on the resistance of input electrical impedance. To compute the time varying resistance of input electrical impedance, the welding voltage and current signals are measured simultaneously and then converted into complex-valued signals by using Hilbert transform. Comparing with the dynamic contact resistance as reported in literature, it showed that the time varying resistance of input electrical impedance can be accurately correlated with the physical changes of weld nugget growth. Therefore, it can be used to characterize the in-process changes of weld nugget growth. Several new findings were reported based on the investigation of spot welds under no weld, with and without weld expulsion conditions.展开更多
基金Supported by the EU 7th Framework ICT Programme under Euro Energest Project(Contract No.288102)
文摘As energy efficiency is one of the key essentials towards sustainability, the development of an energy-resource efficient manufacturing system is among the great challenges facing the current industry. Meanwhile, the availability of advanced technological innovation has created more complex manufacturing systems that involve a large variety of processes and machines serving different functions. To extend the limited knowledge on energy-efficient scheduling, the research presented in this paper attempts to model the production schedule at an operation process by considering the balance of energy consumption reduction in production, production work flow （productivity） and quality. An innovative systematic approach to manufacturing energy-resource efficiency is proposed with the virtual simulation as a predictive modelling enabler, which provides real-time manufacturing monitoring, virtual displays and decision-makings and consequentially an analytical and multidimensional correlation analysis on interdependent relationships among energy consumption, work flow and quality errors. The regression analysis results demonstrate positive relationships between the work flow and quality errors and the work flow and energy consumption. When production scheduling is controlled through optimization of work flow, quality errors and overall energy consumption, the energy-resource efficiency can be achieved in the production. Together, this proposed multidimensional modelling and analysis approach provides optimal conditions for the production scheduling at the manufacturing system by taking account of production quality, energy consumption and resource efficiency, which can lead to the key competitive advantages and sustainability of the system operations in the industry.
文摘The most significant characteristic in frequency domain during cutting chatter occurring process is the steep rise of the vibration energy in certain narrow frequency band containing the chatter frequency. In accordance with the frequency band-energy principle, a reliable criterion for chatter judgement is proposed and the in-process detection of cutting chatter is realized by the use of microcomputer. This method has the advantages of rapidity, high sensitivity, accuracy and high resistance to interference. Some concrete measures taken in practical applications are also discussed.
基金This work was supported by JSPS KAKENHI Grant Number JP18K14142was performed for the Council for Science,Technology and Innovation(CSTI),Cross-ministerial Strategic Innovation Promotion Program(SIP),“Photonics and Quantum Technology for Society 5.0”(Funding agency:QST).
文摘A line-shaped beam is useful for increasing the processing speed in laser grooving and scribing.In laser grooving,depth control of the processed structure is important for performing precise processing.In this paper,in-process monitoring of the depth of a structure formed by femtosecond laser processing with a line-shaped beam using swept-source optical coherence tomography(SS-OCT)was demonstrated.In the evaluation of the SS-OCT system,the depth resolution,measurement accuracy,and axial measurable range were 15.8μm,±2.5μm and 5.3 mm,respectively.In laser grooving,the structural shape and the distribution of deposited debris were successfully monitored.The measured depth agreed well with the depth obtained using a laser confocal microscope.The proposed method will be effective for precise laser processing with feedback control of the laser parameters based on in-process monitoring of the processed structure.
基金This work was supported by the National Key Research and Development Plan of China under Grant No.2016YFB1000200the National Natural Science Foundation of China under Grant No.61772497the State Key Laboratory of Computer Architecture Foundation under Grant Nos.CARCH4405 and CARCH2601.
文摘In recent years many security attacks occur when malicious codes abuse in-process memory resources.Due to the increasing complexity,an application program may call third-party code which cannot be controlled by programmers but may contain security vulnerabilities.As a result,the users have the risk of suffering information leakage and control flow hijacking.However,current solutions like Intel memory protection extensions(MPX)severely degrade performance,while other approaches like Intel memory protection keys(MPK)lack flexibility in dividing security domains.In this paper,we propose IMPULP,an effective and efficient hardware approach for in-process memory protection.The rationale of IMPULP is user-level partitioning that user code segments are divided into different security domains according to their instruction addresses,and accessible memory spaces are specified dynamically for each domain via a set of boundary registers.Each instruction related to memory access will be checked according to its security domain and the corresponding boundaries,and illegal in-process memory access of untrusted code segments will be prevented.IMPULP can be leveraged to prevent a wide range of in-process memory abuse attacks,such as buffer overflows and memory leakages.For verification,an FPGA prototype based on RISC-V instruction set architecture has been developed.We present eight tests to verify the effectiveness of IMPULP,including five memory protection function tests,a test to defense typical buffer overflow,a test to defense famous memory leakage attack named Heartbleed,and a test for security benchmark.We execute the SPEC CPU2006 benchmark programs to evaluate the efficiency of IMPULP.The performance overhead of IMPULP is less than 0.2%runtime on average,which is negligible.Moreover,the resource overhead is less than 5.5%for hardware modification of IMPULP.
基金supported by A-STEP from JST and MEXT/JSPS KAKENHI(No.18K18803,20H02040)The authors thank Assistant Professor L.Jin from RCAST,the University of Tokyo,for providing the measured tapered optical fiber.
文摘In this paper,we propose an in-process measurement method of the diameter of micro-optical fiber such as a tapered optical fiber.The proposed technique is based on analyzing optically scattered light generated by standing wave illumination.The proposed method is significant in that it requires an only limited measurement range and does not require a high dynamic range sensor.These properties are suitable for in-process measurement.This experiment verified that the proposed method could measure a fiber diameter as stable as±0.01μm under an air turbulence environment.As a result of comparing the measured diameter distribution with those by scanning electron microscopy,it was confirmed that the proposed method has a measurement accuracy better than several hundred nanometers.
文摘The constructing method of a simulation system is discussed in this paper. It is for a Decision Support System (DSS) of main in-process warehouse on a large scale flexible production line. This system is decomposed into three function blocks: DSS, support environment for simulation, simulating dispatch module. It has a fine structure and works coordinatively to complete whatever assignment for simulation tasks of a complicated production system.
基金Project supported by the National Natural Science Foundation of China (No. 50238050).
文摘UNITANK is a biological wastewater treatment process that combines the advantages of traditional activated sludge process and sequencing batch reactor, which is divided into Tank A, B and C. In this study, the sludge distribution and its impact on performance of UNITANK were carried out in Liede Wastewater Plant （WWTP） of Guangzhou, China. Results showed that there was a strong affiliation between Tank A and B of the system in sludge concentration distribution. The initial sludge concentration in Tank A could present the sludge distribution of the whole system. The sludge distribution was mainly influenced by hydraulic condition. Unsteady sludge distribution had an impact on variations of substrates in reactors, especially in decisive reactor, and this could lead to failure of system. Settler could partially remove substrates such as COD and NO3-N, but there was adventure of sludge deterioration. The rational initial sludge concentration in Tank A should be 4000-6000 mg/L MLSS.
基金Project(IRT0708) supported by Program for Changjiang Scholars and Innovative Research Team in University of China ("PCSIRT")Project(20070008031) supported by the Research Fund for the Dectoral Program of Higher Education of China
文摘A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel slag before air quenching can more effectively improve the slag's grindability than milltailings, which is the other modification agent tested under the same conditions. The role of fly ash is strengthened as its proportion increases, although the degree of promotion is gradually reduced. As a result of the reaction between fly ash and steel slag at high temperature, some new mineral phases and vitreous bodies with fine grindability promote the slag grinding easily. This work is helpful to making a comprehensive utilization of steel slag and maximize its economic efficiency in China.
文摘The in-process changes of weld nugget growth during the Resistance Spot Welding were investigated based on the resistance of input electrical impedance. To compute the time varying resistance of input electrical impedance, the welding voltage and current signals are measured simultaneously and then converted into complex-valued signals by using Hilbert transform. Comparing with the dynamic contact resistance as reported in literature, it showed that the time varying resistance of input electrical impedance can be accurately correlated with the physical changes of weld nugget growth. Therefore, it can be used to characterize the in-process changes of weld nugget growth. Several new findings were reported based on the investigation of spot welds under no weld, with and without weld expulsion conditions.
