Most cited articles
2013, 2(1):1-7.
Abstract:
Random Forests is an important ensemble learning method and it is widely used in data classification and nonparametric regression. In this paper, we review three main theoretical issues of random forests, i.e., the convergence theorem, the generalization error bound and the out-of-bag estimation. In the end, we present an improved Random Forests algorithm, which uses a feature weighting sampling method to sample a subset of features at each node in growing trees. The new method is suitable to solve classification problems of very high dimensional data.
Random Forests is an important ensemble learning method and it is widely used in data classification and nonparametric regression. In this paper, we review three main theoretical issues of random forests, i.e., the convergence theorem, the generalization error bound and the out-of-bag estimation. In the end, we present an improved Random Forests algorithm, which uses a feature weighting sampling method to sample a subset of features at each node in growing trees. The new method is suitable to solve classification problems of very high dimensional data.
2 Rapid Detecting Method for Pseudosciaena Crocea Morphological Parameters Based on the Machine Vision
2014, 3(5):45-51.
DOI: 10.12146/j.issn.2095-3135.201405006
Abstract:
Morphological parameter measurement of Pseudosciaena Crocea plays an important role in its genetic selection and quality improvement. In this paper, an automatic detecting system which can measure the Pseudosciaena Crocea morphological parameters such as weight, length and body width was developed based on the machine vision and weighing sensor technology. The system can automatically detect the external morphology parameters by the machine vision, and get weight parameters through the weighing sensor. The mean errors of dimensional measurement and weighting are 0.28% and 0.74% respectively, which shows that the developed system can completely meet the requirements of morphological parameter measurement for Pseudosciaena Crocea. It is a new effective method to the automatic detection of fish morphology parameters.
Morphological parameter measurement of Pseudosciaena Crocea plays an important role in its genetic selection and quality improvement. In this paper, an automatic detecting system which can measure the Pseudosciaena Crocea morphological parameters such as weight, length and body width was developed based on the machine vision and weighing sensor technology. The system can automatically detect the external morphology parameters by the machine vision, and get weight parameters through the weighing sensor. The mean errors of dimensional measurement and weighting are 0.28% and 0.74% respectively, which shows that the developed system can completely meet the requirements of morphological parameter measurement for Pseudosciaena Crocea. It is a new effective method to the automatic detection of fish morphology parameters.
LIU Hengwei
,
LI Jianjun
,
XIE Xiaoyi
,
FANG Mou
,
WANG Li
,
HE Xiangming
,
OUYANG Minggao
,
LI Maogang
2015, 4(1):51-59.
DOI: 10.12146/j.issn.2095-3135.201501007
Abstract:
In this work the thermal behavior of the LiNi1/3Co1/3Mn1/3O2 cathode material for soft packed lithium-ion power batteries during charging and discharging at different C-rate were conducted using the ARC (accelerating rate calorimeter) to provide an adiabatic environment. The overall heat generated by the lithium-ion battery during use, is partly reversible and partly irreversible, due to entropy change and joule heating, respectively. It indicates that the heating generation of lithium-ion cell is decided by the C-rate of charge and discharge. The heat is smaller at low C-rate of charge and discharge. For example, the heating generation of battery increases 7.16℃ at 0.2C-rate and the entropy change heat is clearly embodied. The joule heating is more remarkable than the entropy change during charging and discharging at high C-rate. For instance, the heating generation of cell increased 25.63℃ at 1C-rate. The heat generation of charge is less than discharge at the same C-rate. The DC inter insistence of cell at the SOC (State of Charge) of 0 to 10% increases suddenly, so the heating generation power will reach its maximum in this period during discharge. It is valuable for the design of heat dissipation in lithium-ion battery thermal management.
In this work the thermal behavior of the LiNi1/3Co1/3Mn1/3O2 cathode material for soft packed lithium-ion power batteries during charging and discharging at different C-rate were conducted using the ARC (accelerating rate calorimeter) to provide an adiabatic environment. The overall heat generated by the lithium-ion battery during use, is partly reversible and partly irreversible, due to entropy change and joule heating, respectively. It indicates that the heating generation of lithium-ion cell is decided by the C-rate of charge and discharge. The heat is smaller at low C-rate of charge and discharge. For example, the heating generation of battery increases 7.16℃ at 0.2C-rate and the entropy change heat is clearly embodied. The joule heating is more remarkable than the entropy change during charging and discharging at high C-rate. For instance, the heating generation of cell increased 25.63℃ at 1C-rate. The heat generation of charge is less than discharge at the same C-rate. The DC inter insistence of cell at the SOC (State of Charge) of 0 to 10% increases suddenly, so the heating generation power will reach its maximum in this period during discharge. It is valuable for the design of heat dissipation in lithium-ion battery thermal management.
2013, 2(1):23-28.
Abstract:
In order to help the hearing loss children, we obtained hearing loss children’s fallible pronunciation texts and the confusing pronunciation text pairs form a good deal of hearing loss children’s audio pronunciation data. We designed a data-driven 3D talking head articulatory animation system, it was driven by the articulatory movements which were collected from a device called Electro-magnetic articulography (EMA) AG500, the system simulated Chinese articulation realistically. In that way, the hearing loss children can observe the speaker’s lips and tongue’s motions during the speaker pronouncing, which could help the hearing loss children train pronunciation and correct the fallible pronunciations. Finally, a perception test was applied to evaluate the system’s performance. The results showed that the 3D talking head system can animate both internal and external articulatory motions effectively. A modified CM model based synthesis method was used to generate the articulatory movements. The root mean square between the real articulatory movements and synthetic articulatory movements was used to measure the synthesis method, and an average value of RMS is 1.25 mm.
In order to help the hearing loss children, we obtained hearing loss children’s fallible pronunciation texts and the confusing pronunciation text pairs form a good deal of hearing loss children’s audio pronunciation data. We designed a data-driven 3D talking head articulatory animation system, it was driven by the articulatory movements which were collected from a device called Electro-magnetic articulography (EMA) AG500, the system simulated Chinese articulation realistically. In that way, the hearing loss children can observe the speaker’s lips and tongue’s motions during the speaker pronouncing, which could help the hearing loss children train pronunciation and correct the fallible pronunciations. Finally, a perception test was applied to evaluate the system’s performance. The results showed that the 3D talking head system can animate both internal and external articulatory motions effectively. A modified CM model based synthesis method was used to generate the articulatory movements. The root mean square between the real articulatory movements and synthetic articulatory movements was used to measure the synthesis method, and an average value of RMS is 1.25 mm.
2017, 6(2):41-48.
DOI: 10.12146/j.issn.2095-3135.201702005
Abstract:
Medical imaging is a complicated procedure and acquired images are with intrinsic characteristics. As a tool to quantify the image quality, signal-to-noise ratio (SNR) is widely accepted by physicians in clinical situations. It is defined as the quotient of the mean signal intensity in a tissue region of interest and the standard deviation of the signal intensity in a region outside the anatomy of the object imaged. However, insufficient knowledge on its consistency with respect to different observers and tissue regions is known. In this paper, the consistency is studied with 324 simulated MR images of human brain. The consistency of SNR is validated between two observers and between tissues of white matter and cerebral spinal fluid. For the same type of tissues in each modality, Wilcoxon rank sum test suggests no significant difference between two observers(P＞0.70). For the same modality and observer, SNR between tissues correlates well (Pearson correlation coefficient rp＞0.71(P＜10－5), and Spearman’s rank correlation coefficient rs＞0.97(P＜10－3). This study indicates that SNR is consistent and robust regarding to different observers and tissues in objective quality assessment of magnetic resonance images. Further research will be carried on clinical images for objective assessment.
Medical imaging is a complicated procedure and acquired images are with intrinsic characteristics. As a tool to quantify the image quality, signal-to-noise ratio (SNR) is widely accepted by physicians in clinical situations. It is defined as the quotient of the mean signal intensity in a tissue region of interest and the standard deviation of the signal intensity in a region outside the anatomy of the object imaged. However, insufficient knowledge on its consistency with respect to different observers and tissue regions is known. In this paper, the consistency is studied with 324 simulated MR images of human brain. The consistency of SNR is validated between two observers and between tissues of white matter and cerebral spinal fluid. For the same type of tissues in each modality, Wilcoxon rank sum test suggests no significant difference between two observers(P＞0.70). For the same modality and observer, SNR between tissues correlates well (Pearson correlation coefficient rp＞0.71(P＜10－5), and Spearman’s rank correlation coefficient rs＞0.97(P＜10－3). This study indicates that SNR is consistent and robust regarding to different observers and tissues in objective quality assessment of magnetic resonance images. Further research will be carried on clinical images for objective assessment.
2017, 6(2):11-21.
DOI: 10.12146/j.issn.2095-3135.201702002
Abstract:
Greenhouse mapping has attracted much attention recently, especially in China where greenhouse practice has been growing dramatically. Remote sensing based greenhouse extraction methods can generate the geographical locations and spatial distribution of greenhouses efficiently. Most of the existing greenhouse extraction algorithms rely on high-resolution remote sensing images or aerial images, which are often expensive to obtain and require complicated algorithms to process. To solve this problem, this paper proposes a fast algorithm for greenhouse extraction based on Landsat images that are freely available. First, an enhanced water index was introduced to characterize winter greenhouse, based on an observed natural phenomenon that water vapor inside a greenhouse is usually condensed to form a layer of dew on the inner surface of the greenhouse plastic or glass. On one hand, the dew layer makes a greenhouse has a high water index value, which makes it to be distinguished easily from bare land. On the other hand, the dew layer increases a greenhouse’s reflectivity, which makes it different from natural water bodies. In order to extract greenhouses, a simple and efficient decision tree classifier was designed. Da’ao town of Jiangmen in Guangdong Province was chosen as an example, and the experiments were based on Landsat images taken in different years. The results show that the proposed method is effective in extracting greenhouses, with the advantages of high efficiency, low cost, and strong robustness.
Greenhouse mapping has attracted much attention recently, especially in China where greenhouse practice has been growing dramatically. Remote sensing based greenhouse extraction methods can generate the geographical locations and spatial distribution of greenhouses efficiently. Most of the existing greenhouse extraction algorithms rely on high-resolution remote sensing images or aerial images, which are often expensive to obtain and require complicated algorithms to process. To solve this problem, this paper proposes a fast algorithm for greenhouse extraction based on Landsat images that are freely available. First, an enhanced water index was introduced to characterize winter greenhouse, based on an observed natural phenomenon that water vapor inside a greenhouse is usually condensed to form a layer of dew on the inner surface of the greenhouse plastic or glass. On one hand, the dew layer makes a greenhouse has a high water index value, which makes it to be distinguished easily from bare land. On the other hand, the dew layer increases a greenhouse’s reflectivity, which makes it different from natural water bodies. In order to extract greenhouses, a simple and efficient decision tree classifier was designed. Da’ao town of Jiangmen in Guangdong Province was chosen as an example, and the experiments were based on Landsat images taken in different years. The results show that the proposed method is effective in extracting greenhouses, with the advantages of high efficiency, low cost, and strong robustness.
2016, 5(1):85-90.
DOI: 10.12146/j.issn.2095-3135.201601010
Abstract:
In current marine low-temperature distillation seawater desalination plant, an ejector is designed to pump gas and water synchronously so as to reduce device size and energy consuming. In this paper, an ejector design scheme with two stages was investigated. Flow field characteristic of the proposed ejector was simulated to demonstrate that this design could increase inlet flow velocity and pressure which in turn could improve inlet vacuum and decrease vacuum. Real experiments were also carried out to validate the simulated results. The experimental results show that, when the flow velocity is larger than 3.5 m/s, vacuum at ejector suction can reach 92% and 90% respectively and meet the performance requirements of marine ejector.
In current marine low-temperature distillation seawater desalination plant, an ejector is designed to pump gas and water synchronously so as to reduce device size and energy consuming. In this paper, an ejector design scheme with two stages was investigated. Flow field characteristic of the proposed ejector was simulated to demonstrate that this design could increase inlet flow velocity and pressure which in turn could improve inlet vacuum and decrease vacuum. Real experiments were also carried out to validate the simulated results. The experimental results show that, when the flow velocity is larger than 3.5 m/s, vacuum at ejector suction can reach 92% and 90% respectively and meet the performance requirements of marine ejector.
2014, 3(6):84-91.
DOI: 10.12146/j.issn.2095-3135.201406011
Abstract:
As the high density package is moving towards miniaturization, high I/O density, better thermal and high reliable system, the conventional wire bonding technology can not satisfy the product need already. The advanced flip chip technology is highly expected due to its high area array I/O interconnection, short signal path, high thermal dissipation, high electrical and thermal performance. In order to enhance the reliability of a flip-chip on organic board package, underfill is used between the chip and the substrate to redistribute the thermo-mechanical stress created by the coefficient of thermal expansion (CTE) mismatch between the silicon chip and organic substrate. However, the conventional underfill relies on the capillary flow of the underfill material and has many disadvantages. In order to overcome these disadvantages, no-flow underfill has been invented to improve the flip-chip underfill process. This paper reviews the development of flipchip technology and expounds the behavior of flow and no-flow underfill.
As the high density package is moving towards miniaturization, high I/O density, better thermal and high reliable system, the conventional wire bonding technology can not satisfy the product need already. The advanced flip chip technology is highly expected due to its high area array I/O interconnection, short signal path, high thermal dissipation, high electrical and thermal performance. In order to enhance the reliability of a flip-chip on organic board package, underfill is used between the chip and the substrate to redistribute the thermo-mechanical stress created by the coefficient of thermal expansion (CTE) mismatch between the silicon chip and organic substrate. However, the conventional underfill relies on the capillary flow of the underfill material and has many disadvantages. In order to overcome these disadvantages, no-flow underfill has been invented to improve the flip-chip underfill process. This paper reviews the development of flipchip technology and expounds the behavior of flow and no-flow underfill.
2014, 3(6):76-83.
DOI: 10.12146/j.issn.2095-3135.201406010
Abstract:
The main functions of substrates in electronic packaging include supporting, cooling, protection of semiconductor chips, as well as insulation and electronic interconnection with external chips. With the electronic packaging developing towards high speed, multi-functionalization, high performance, good stability and small dimension, substrates play more and more important role in the field of new generation electronics packaging. Scientists and engineers have higher requirement to substrate materials, which advances their brilliant progress. In this review, the characteristic, recent progress and future development of three kinds of substrates were summerized, including ceramic, composite and organic substrates.
The main functions of substrates in electronic packaging include supporting, cooling, protection of semiconductor chips, as well as insulation and electronic interconnection with external chips. With the electronic packaging developing towards high speed, multi-functionalization, high performance, good stability and small dimension, substrates play more and more important role in the field of new generation electronics packaging. Scientists and engineers have higher requirement to substrate materials, which advances their brilliant progress. In this review, the characteristic, recent progress and future development of three kinds of substrates were summerized, including ceramic, composite and organic substrates.
2014, 3(1):18-26.
DOI: 10.12146/j.issn.2095-3135.201401002
Abstract:
Thermal issues of lithium-ion batteries for automotive application are key factors affecting the performance, safety, life and cost of electric vehicles. In this work, the thermal management systems of three typical electric vehicles were analyzed to identify the importance of the thermal design for the single batteries. Special attention was paid to the review of the thermal modeling, which served as the fundamental method for the thermal design. Finally, the directions for further researches on the thermal modeling and thermal design were summarized.
Thermal issues of lithium-ion batteries for automotive application are key factors affecting the performance, safety, life and cost of electric vehicles. In this work, the thermal management systems of three typical electric vehicles were analyzed to identify the importance of the thermal design for the single batteries. Special attention was paid to the review of the thermal modeling, which served as the fundamental method for the thermal design. Finally, the directions for further researches on the thermal modeling and thermal design were summarized.
2013, 2(5):42-47.
DOI: 10.12146/j.issn.2095-3135.201309008
Abstract:
Micro-scale manipulation is a technology of manipulating micro/nanoparticles precisely including trapping, filtering, moving and sorting particles like cells, biomacromolecules and nano drugs, with a vast array of potential uses in biomedicine, chemical analysis, materials science and other fields. By applying acoustic waves, acoustic manipulation has some advantages including non-contact, penetrability and versatility, no biochemical decorations to particles. In recent years, the manipulation of particles based on surface acoustic wave (SAW) has attracted wide attention with the development of MEMS technology and microfluidics science. Due to the advantages such as high frequency, localization of the energy and easy integration with other on-chip units, the microfluidic chip is an excellent tool to observe the manipulation of cells, microbubbles and other bioparticles. In this paper, recent advancements in acoustic manipulation using acoustic steaming and radiation force were discussed. In addition, some perspectives on the future development of this dynamic field were proposed as well.
Micro-scale manipulation is a technology of manipulating micro/nanoparticles precisely including trapping, filtering, moving and sorting particles like cells, biomacromolecules and nano drugs, with a vast array of potential uses in biomedicine, chemical analysis, materials science and other fields. By applying acoustic waves, acoustic manipulation has some advantages including non-contact, penetrability and versatility, no biochemical decorations to particles. In recent years, the manipulation of particles based on surface acoustic wave (SAW) has attracted wide attention with the development of MEMS technology and microfluidics science. Due to the advantages such as high frequency, localization of the energy and easy integration with other on-chip units, the microfluidic chip is an excellent tool to observe the manipulation of cells, microbubbles and other bioparticles. In this paper, recent advancements in acoustic manipulation using acoustic steaming and radiation force were discussed. In addition, some perspectives on the future development of this dynamic field were proposed as well.
2012, 1(3):28-34.
DOI: 10.12146/j.issn.2095-3135.201209006
Abstract:
Defibrotide is a polydisperse oligonucleotide with multiple effects on endothelial cells, which has been developed for the treatment of different vascular disorders. Defibrotide has been used effectively in the treatment and prophylaxis of hepatic veno-occlusive disease. Recent animal models have clearly suggested an antiangiogenic effect and an anticancer activity. Further in vitro and in vivo investigations are needed.
Defibrotide is a polydisperse oligonucleotide with multiple effects on endothelial cells, which has been developed for the treatment of different vascular disorders. Defibrotide has been used effectively in the treatment and prophylaxis of hepatic veno-occlusive disease. Recent animal models have clearly suggested an antiangiogenic effect and an anticancer activity. Further in vitro and in vivo investigations are needed.
2012, 1(2):84-87.
DOI: 10.12146/j.issn.2095-3135.201207017
Abstract:
Smart city and smart planet are the new stages of global information development. As the core technology for the development of smart city, high performance computing got new challenges and opportunities. The challenges of smart city to high performance computing include: massive data computing, realtime computing, social computing and effective computing. Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences, is working on these areas; the latest development and infrastructure built at SIAT are summarized in this paper.
Smart city and smart planet are the new stages of global information development. As the core technology for the development of smart city, high performance computing got new challenges and opportunities. The challenges of smart city to high performance computing include: massive data computing, realtime computing, social computing and effective computing. Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences, is working on these areas; the latest development and infrastructure built at SIAT are summarized in this paper.
2012, 1(1):48-54.
DOI: 10.12146/j.issn.2095-3135.201205008
Abstract:
This paper gives a comprehensive introduction to the status of current machine translation research and technology, and analyzes the key problems to be resolved. Finally our idea of the future trends and prospects of machine translation are put forward.
This paper gives a comprehensive introduction to the status of current machine translation research and technology, and analyzes the key problems to be resolved. Finally our idea of the future trends and prospects of machine translation are put forward.
