In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are train...In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are trained and validated using the Transformer model.In the proposed model,the eight-layer transformer encoders are connected in series and the encoder layer of each Transformer consists of the multi-head attention layer and the feed-forward neural network layer.The experimental results show that the measured and modeled S-parameters of the HEMT device match well in the frequency range of 0.5-40 GHz,with the errors versus frequency less than 1%.Compared with other models,good accuracy can be achieved to verify the effectiveness of the proposed model.展开更多
Objective To comparatively observe the effect of electroacupuncture at digestive system-related lower he-sea points on the expressions of serum interleukin-1β（IL-1 β）, tumor necrosis factor-α（TNF-α） of colon t...Objective To comparatively observe the effect of electroacupuncture at digestive system-related lower he-sea points on the expressions of serum interleukin-1β（IL-1 β）, tumor necrosis factor-α（TNF-α） of colon tissues and high mobility group box 1 protein（HMGB 1） of ulcerative colitis（UC） model rats, and to explore whether there is relative specificity of electroacupuncture at Shàngjùxū（上巨虚 ST 37）, one of lower he-sea points of large intestine, in treatment of bowel diseases. Method A total of 60 SD rats were randomly divided into control group, model group, ST 37 group, Zúsānl？（足三里 ST 36） group, Xiàjùxū（下巨虚 ST 39） group and Yánglíngquán（阳陵泉 GB 34） group. There were ten rats in each group; five were males, and five were females. UC models were established by clysis with 2, 4, 6-trinitrobenzene sulfonic acid/alcohol solution. After modeling, treatment was conducted for ten days, specimens were collected, colonic ulcers and inflammation were inspected visually and scored. The content of serum IL-1β and the expressions of TNF-α and HMGB 1 in colon were detected through ELISA. Results 1 Compared with control group, the scores of colonic ulcers and inflammation, the content of serum IL-1β and the expressions of TNF-α（except ST 37 group） and HMGB 1 were all higher（P〈0.05, P〈0.01）; 2 compared with model group, the scores of colonic ulcers in ST 36 group and ST 37 group were lower obviously（P〈0.05, P〈0.01）; the expressions of IL-1β, TNF-α and HMGB 1 in the four treatment groups were lower obviously（P〈0.01）; 3 compared with ST 37 group, the expressions of IL-1β, TNF-α and HMGB 1 in other three treatment groups were higher obviously（P〈0.05, P〈0.01）; and the scores of colonic ulcers in ST 39 group and GB 34 group were higher obviously（P〈0.05）. Conclusion 1 The score of colonic ulcers can be reduced through electroacupuncture at ST 37, ST 36, ST 39 and GB 34, which can also reduce the content of serum IL-1β and the expressions of TNF-α and HMGB 1, and effectively inhibit inflammatory response of colon caused by UC; 2 the effect trend of the four acupoints in treatment of UC is： ST 37ST 36ST 39GB 34, and electroacupuncture at ST 37 has the best effect with relative specificity.展开更多
In this paper we present a novel approach to modeling AlGaN/GaN high electron mobility transistor （HEMT） with an artificial neural network （ANN）. The AlGaN/GaN HEMT device structure and its fabrication process are...In this paper we present a novel approach to modeling AlGaN/GaN high electron mobility transistor （HEMT） with an artificial neural network （ANN）. The AlGaN/GaN HEMT device structure and its fabrication process are described. The circuit-based Neuro-space mapping （neuro-SM） technique is studied in detail. The EEHEMT model is implemented according to the measurement results of the designed device, which serves as a coarse model. An ANN is proposed to model AIGaN/CaN HEMT based on the coarse model. Its optimization is performed. The simulation results from the model are compared with the measurement results. It is shown that the simulation results obtained from the ANN model of A1GaN/GaN HEMT are more accurate than those obtained from the EEHEMT model.展开更多
Yingqiong basin is a proven hydrocarbon-rich basin in South China Sea. There are a number of large exploration prospects in high temperature and over-pressured formations, especially in Yacheng Block of Qiongdongnan b...Yingqiong basin is a proven hydrocarbon-rich basin in South China Sea. There are a number of large exploration prospects in high temperature and over-pressured formations, especially in Yacheng Block of Qiongdongnan basin and Dongfang District of Yinggehai Basin. Owing to good exploration situation, we have already achieved proven geological reserves over 1000 × 108 m3. In recent years, a few drilled HPHT wells have confirmed that pressure predicted by conventional method was wildly inaccurate. From the view of regional stress, the accuracy of the pressure prediction will be substantially improved. Accurate pressure prediction and three-dimensional pressure modeling which are based on three-dimensional lithology modeling are the cornerstone to achieve exploration breakthrough. In this paper, the use of the triple constraint trend lithology model broke through the traditional method of seismic lithology prediction only by means of impedance threshold value. Compared with actual data and prediction, it confirms that three-dimensional pressure modeling method is reasonable and effective, and has a wide prospect of application.展开更多
A high altitude platform station （HAPS） based communications scenario for providing Intemet access and broadband multimedia services to the passengers on board of a high speed train （traveling up to 300km/h） is pr...A high altitude platform station （HAPS） based communications scenario for providing Intemet access and broadband multimedia services to the passengers on board of a high speed train （traveling up to 300km/h） is proposed. Regarding the addressed scenario, when the propagation link between HAPS and train is blocked by obstacles, a three-dimensional （3-D） geometrical single cylinder spatial-temporal channel model is presented, in which closed form, mathematically tractable space-time correlation functions are obtained. It shows that the correlation functions determined by the 3-D model are of significant difference with those of the conventional 2-D model. Based on the analysis model, the paper derives a realized simulation model using sum-of-sinusoids approach, and applies method of equal areas （MEA） and modified method of equal areas （MMEA） to determine the model parameters. The fitting performance of the simulation model with the analysis one is evaluated by two means-square error （MSE） performance criteria. Finally, numerical simulation results verify the mathematical analysis conclusion, when N ≥21, simulation model has an excellent fitness with the analysis one.展开更多
High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a ...High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a big challenge to FAIMS spectral peak analysis. In this work, a universal and effective model of FAIMS spectral peak profile has been proposed by introducing ion trajectory and loss height. With this model, the influence of the structure of ion drift tube, dispersion voltages, compensation voltages, and carrier gas flow rate on the FAIMS spectral peak characteristics like peak shape, full width at half maximum and peak height is analyzed and discussed. The results show that the influence of different factors on the FAIMS spectral peak profile can be qualitatively described by the model which agrees with the experimental data.展开更多
Since mobile networks are not currently deployed on a large scale, research in this area is mostly by simulation. Among other simulation parameters, the mobility model plays a very important role in determining the pr...Since mobile networks are not currently deployed on a large scale, research in this area is mostly by simulation. Among other simulation parameters, the mobility model plays a very important role in determining the protocol performance in MANET. Based on random direction mobility model, a high dynamic adaptive mobility network model is proposed in the paper. The algorithms and modeling are mainly studied and explained in detail. The technique keystone is that normal distribution is combined with uniform distribution and inertial feedback control is combined with kinematics, through the adaptive control on nodes speed and prediction tracking on nodes routes, an adaptive model is designed, which can be used in simulations to produce realistic and dynamic network scenarios. It is the adaptability that nodes mobile parameters can be adjusted randomly in threedimensional space. As a whole, colony mobility can show some rules. Such random movement processes as varied speed and dwells are simulated realistically. Such problems as sharp turns and urgent stops are smoothed well. The model can be adapted to not only common dynamic scenarios, but also high dynamic scenarios. Finally, the mobility model performance is analyzed and validated based on random dynamic scenarios simulations.展开更多
BACKGROUND Acetaminophen overdose is the most frequent cause of drug-induced liver failure in developed countries.Substantial progress has been made in understanding the mechanism of hepatocellular injury,but N-acetyl...BACKGROUND Acetaminophen overdose is the most frequent cause of drug-induced liver failure in developed countries.Substantial progress has been made in understanding the mechanism of hepatocellular injury,but N-acetylcysteine remains the only effective treatment despite its short therapeutic window.Thus,other hepatoprotective drugs are needed for the delayed treatment of acetaminopheninduced hepatotoxicity.Our interest focused on glycyrrhizin for its role as an inhibitor of high mobility group box 1(HMGB1)protein,a member of the family of damage-associated molecular pattern,known to play an important pathological role in various diseases.AIM To investigate the efficacy of the N-acetylcysteine/glycyrrhizin combination compared to N-acetylcysteine alone in the prevention of liver toxicity.METHODS Eight-week-old C57BL/6J wild-type female mice were used for all our experiments.Mice fasted for 15 h were treated with acetaminophen(500 mg/kg)or vehicle(phosphate-buffered saline)by intraperitoneal injection and separated into the following groups:Glycyrrhizin(200 mg/kg);N-acetylcysteine(150 mg/kg);and N-acetylcysteine/glycyrrhizin.In all groups,mice were sacrificed 12 h following acetaminophen administration.The assessment of hepatotoxicity was performed by measuring plasma levels of alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase.Hepatotoxicity was also evaluated by histological examination of hematoxylin and eosin-stained tissues sections.Survival rates were compared between various groups using Kaplan-Meier curves.RESULTS Consistent with data published in the literature,we confirmed that intraperitoneal administration of acetaminophen(500 mg/kg)in mice induced severe liver injury as evidenced by increases in alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase but also by liver necrosis score.Glycyrrhizin administration was shown to reduce the release of HMGB1 and significantly decreased the severity of liver injury.Thus,the co-administration of glycyrrhizin and N-acetylcysteine was investigated.Administered concomitantly with acetaminophen,the combination significantly reduced the severity of liver injury.Delayed administration of the combination of drugs,2 h or 6 h after acetaminophen,also induced a significant decrease in hepatocyte necrosis compared to mice treated with N-acetylcysteine alone.In addition,administration of N-acetylcysteine/glycyrrhizin combination was associated with an improved survival rate compared to mice treated with only N-acetylcysteine.CONCLUSION We demonstrate that,compared to N-acetylcysteine alone,co-administration of glycyrrhizin decreases the liver necrosis score and improves survival in a murine model of acetaminophen-induced liver injury.Our study opens a potential new therapeutic pathway in the prevention of acetaminophen hepatotoxicity.展开更多
We have developed a 2D analytical model for the single gate AllnSb/lnSb HEMT device by solving the Poisson equation using the parabolic approximation method. The developed model analyses the device perfomance by calcu...We have developed a 2D analytical model for the single gate AllnSb/lnSb HEMT device by solving the Poisson equation using the parabolic approximation method. The developed model analyses the device perfomance by calculating the parameters such as surface potential, electric field distribution and drain current. The high mobility of the AlInSb/InSb quantum makes this HEMT ideal for high frequency, high power applications. The working of the single gate AllnSb/InSb HEMT device is studied by considering the variation of gate source voltage, drain source voltage, and channel length under the gate region and temperature. The carrier transport efficiency is improved by uniform electric field along the channel and the peak values near the source and drain regions. The results from the analytical model are compared with that of numerical simulations （TCAD） and a good agreement between them is achieved.展开更多
The subduction of the Indian continental lithosphere under the Asian continent caused the uplift of the Tibet Plateau,resulting in the formation of a thickened continental crust twice of the normal value and the crust...The subduction of the Indian continental lithosphere under the Asian continent caused the uplift of the Tibet Plateau,resulting in the formation of a thickened continental crust twice of the normal value and the crustal shortening of at least 1500 km.Therefore,many models have been proposed to explain the shortening and material transportation mechanism of the Tibetan Plateau.展开更多
Short gate-length High Electron Mobility Transistors (HEMTs) have been observed to exhibit kinks in their drain current-voltage (I-V) characteristics. To model this nonlinear effect, we present an effective approach t...Short gate-length High Electron Mobility Transistors (HEMTs) have been observed to exhibit kinks in their drain current-voltage (I-V) characteristics. To model this nonlinear effect, we present an effective approach that is easily incorporated into most existing empirical HEMT I-V models. This has been done by modifying the channel length modulation parameter to account for the kink effect. Moreover, the definitions of the left parameters in the original model will not be influenced, and the improved HEMT I-V model enhances its bias range of operation for which accuracy is maintained. The proposed modeling method is validated through DC/ Pulsed I-V as well as large-signal power measurements.展开更多
The National University Corporation Tsukuba University of Technology(NTUT)is the only institute of higher education for the hearing and the visually impaired in Japan.In our university,hearing or visually impaired stu...The National University Corporation Tsukuba University of Technology(NTUT)is the only institute of higher education for the hearing and the visually impaired in Japan.In our university,hearing or visually impaired students are studying to be technicians after they graduate,toward social independence.From previous experience of higher education for students with disabilities,effects are increased when modeling is used by the teachers involved in professional education.In the Mechanical Engineering Course,we are using modeling,to match the drawing and shape for beginning students.It includes support for enhancing one's view,and how to draw out the ability of mechanical engineering students for the basics.For students to study Mechanical Design and Drawing,Modeling of Gear Pump,Jack and Globe Valve are easily shown through drawings and the operation of each mechanism through sample drawings in the textbook.It is possible to make an opportunity to think about the machine mechanism.It will be shown by students'works.The assembling of the model triggers the need for form accuracy by making a function,and improves the quality of learning.It is possible that a three-dimensional molding machine can be produced through experiential learning by the model,and modeling with the dimension numerical data.Moreover,it is also embodied in a three-dimensional modeling which results in the image processing programming created.Confirming the improvement of the program through the shape with the quality.In the Department of Synthetic Design,students have chances to realize and self-evaluate from the design of the lamp shade with a complicated shape.In the Faculty of Health Science from Department of Health,high quality teaching of visually-impaired students through the use of bone model teaching materials has become possible in the medical-related courses.展开更多
为了精确模拟低温下氮化镓高电子迁移率晶体管(Gallium Nitride high electron mobility transistor,GaN HEMT)的微波噪声性能,提出了一种基于小信号等效电路构建低温噪声模型的方法.利用导纳参数的频率依赖性获取小信号等效电路元件,...为了精确模拟低温下氮化镓高电子迁移率晶体管(Gallium Nitride high electron mobility transistor,GaN HEMT)的微波噪声性能,提出了一种基于小信号等效电路构建低温噪声模型的方法.利用导纳参数的频率依赖性获取小信号等效电路元件,建立了精确的小信号模型.在此基础上依据Pospieszalski原理对低温噪声源进行表征,特别是栅极泄漏引入的散粒噪声,建立了低温噪声模型.仿真结果表明:在0.2~40 GHz频段,小信号模型的S参数最大误差为2.5%,在2~10 GHz频段噪声模型的四噪声参数最大误差仅在1%以内.其中,低温下栅极泄漏散粒噪声贡献约0.1 K,较于传统方法,新方法具有一定的有效性和更高的准确性.展开更多
A compact model is proposed to derive the charge density of the AlInSb/InSb HEMT devices by con- sidering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with appli...A compact model is proposed to derive the charge density of the AlInSb/InSb HEMT devices by con- sidering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with applied gate voltage. The proposed model considers the Fermi level dependence of charge density and vice versa. The analytical results generated by the proposed model are compared and they agree well with the experimental results. The developed model can be used to implement a physics based compact model for an InSb HEMT device in SPICE applications.展开更多
目的探究良性前列腺增生(BPH)患者绿激光解剖性汽化切除术(AVIT)后尿路感染(UTI)情况,并构建风险预测模型。方法收集452例行AVIT治疗的BPH患者,根据术后30 d UTI情况分为感染组(n=102)和未感染组(n=350)。收集2组患者的一般资料,分析影...目的探究良性前列腺增生(BPH)患者绿激光解剖性汽化切除术(AVIT)后尿路感染(UTI)情况,并构建风险预测模型。方法收集452例行AVIT治疗的BPH患者,根据术后30 d UTI情况分为感染组(n=102)和未感染组(n=350)。收集2组患者的一般资料,分析影响AVIT后UTI的可能因素,多重共线性分析筛选变量,logistic回归分析AVIT后UTI的影响因素,建立感染风险预测模型,采用受试者工作特征(ROC)曲线评价模型预测效能。结果2组患者的年龄、糖尿病史、手术时间、联合使用抗菌药物、术中灌注时间、泌尿道手术史、术前尿白细胞(WBC)计数升高、血清高迁移率族蛋白B1(HMGB1)及β-防御素-3(HBD-3)水平比较,差别均有统计学意义(P<0.05);logistic回归分析显示,调整混杂因素后,手术时间≥65 min、联合使用抗菌药物、术中灌注时间≥30 min、泌尿道手术史、术前尿WBC计数升高、血清HMGB1、血清HBD-3水平是AVIT后UTI的危险因素(P<0.05);基于多因素分析构建2个logistic回归模型,Hosmer-Lemeshow检验χ^(2)分别为7.638和5.896,其中新型预测模型预测术后UTI的曲线下面积(AUC)最大,为0.927(95%CI:0.899~0.949);验证模型AUC=0.918(95%CI:0.838~0.966),可获取最佳截断值,模型评分≤13.2分为低危组,评分13.3~16.7分为中危组,评分≥16.8分为高危组。结论血清HMGB1、HBD-3及手术时间≥65 min、联合使用抗菌药物、术中灌注时间≥30 min、泌尿道手术史、术前尿WBC计数升高是BPH患者AVIT后UTI的危险因素,构建的风险预测模型具有较高预测价值,可作为临床预测术后UTI的潜在预测因子。展开更多
基金Supported by the National Natural Science Foundation of China(62201293,62034003)the Open-Foundation of State Key Laboratory of Millimeter-Waves(K202313)the Jiangsu Province Youth Science and Technology Talent Support Project(JSTJ-2024-040)。
文摘In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are trained and validated using the Transformer model.In the proposed model,the eight-layer transformer encoders are connected in series and the encoder layer of each Transformer consists of the multi-head attention layer and the feed-forward neural network layer.The experimental results show that the measured and modeled S-parameters of the HEMT device match well in the frequency range of 0.5-40 GHz,with the errors versus frequency less than 1%.Compared with other models,good accuracy can be achieved to verify the effectiveness of the proposed model.
基金Supported by National Natural Science Foundation of China:81173327/H2718
文摘Objective To comparatively observe the effect of electroacupuncture at digestive system-related lower he-sea points on the expressions of serum interleukin-1β（IL-1 β）, tumor necrosis factor-α（TNF-α） of colon tissues and high mobility group box 1 protein（HMGB 1） of ulcerative colitis（UC） model rats, and to explore whether there is relative specificity of electroacupuncture at Shàngjùxū（上巨虚 ST 37）, one of lower he-sea points of large intestine, in treatment of bowel diseases. Method A total of 60 SD rats were randomly divided into control group, model group, ST 37 group, Zúsānl？（足三里 ST 36） group, Xiàjùxū（下巨虚 ST 39） group and Yánglíngquán（阳陵泉 GB 34） group. There were ten rats in each group; five were males, and five were females. UC models were established by clysis with 2, 4, 6-trinitrobenzene sulfonic acid/alcohol solution. After modeling, treatment was conducted for ten days, specimens were collected, colonic ulcers and inflammation were inspected visually and scored. The content of serum IL-1β and the expressions of TNF-α and HMGB 1 in colon were detected through ELISA. Results 1 Compared with control group, the scores of colonic ulcers and inflammation, the content of serum IL-1β and the expressions of TNF-α（except ST 37 group） and HMGB 1 were all higher（P〈0.05, P〈0.01）; 2 compared with model group, the scores of colonic ulcers in ST 36 group and ST 37 group were lower obviously（P〈0.05, P〈0.01）; the expressions of IL-1β, TNF-α and HMGB 1 in the four treatment groups were lower obviously（P〈0.01）; 3 compared with ST 37 group, the expressions of IL-1β, TNF-α and HMGB 1 in other three treatment groups were higher obviously（P〈0.05, P〈0.01）; and the scores of colonic ulcers in ST 39 group and GB 34 group were higher obviously（P〈0.05）. Conclusion 1 The score of colonic ulcers can be reduced through electroacupuncture at ST 37, ST 36, ST 39 and GB 34, which can also reduce the content of serum IL-1β and the expressions of TNF-α and HMGB 1, and effectively inhibit inflammatory response of colon caused by UC; 2 the effect trend of the four acupoints in treatment of UC is： ST 37ST 36ST 39GB 34, and electroacupuncture at ST 37 has the best effect with relative specificity.
基金supported by the National Natural Science Foundation of China (Grant No. 60776052)
文摘In this paper we present a novel approach to modeling AlGaN/GaN high electron mobility transistor （HEMT） with an artificial neural network （ANN）. The AlGaN/GaN HEMT device structure and its fabrication process are described. The circuit-based Neuro-space mapping （neuro-SM） technique is studied in detail. The EEHEMT model is implemented according to the measurement results of the designed device, which serves as a coarse model. An ANN is proposed to model AIGaN/CaN HEMT based on the coarse model. Its optimization is performed. The simulation results from the model are compared with the measurement results. It is shown that the simulation results obtained from the ANN model of A1GaN/GaN HEMT are more accurate than those obtained from the EEHEMT model.
文摘Yingqiong basin is a proven hydrocarbon-rich basin in South China Sea. There are a number of large exploration prospects in high temperature and over-pressured formations, especially in Yacheng Block of Qiongdongnan basin and Dongfang District of Yinggehai Basin. Owing to good exploration situation, we have already achieved proven geological reserves over 1000 × 108 m3. In recent years, a few drilled HPHT wells have confirmed that pressure predicted by conventional method was wildly inaccurate. From the view of regional stress, the accuracy of the pressure prediction will be substantially improved. Accurate pressure prediction and three-dimensional pressure modeling which are based on three-dimensional lithology modeling are the cornerstone to achieve exploration breakthrough. In this paper, the use of the triple constraint trend lithology model broke through the traditional method of seismic lithology prediction only by means of impedance threshold value. Compared with actual data and prediction, it confirms that three-dimensional pressure modeling method is reasonable and effective, and has a wide prospect of application.
基金Supported by the National Natural Science Foundation of China (No. 60532030).
文摘A high altitude platform station （HAPS） based communications scenario for providing Intemet access and broadband multimedia services to the passengers on board of a high speed train （traveling up to 300km/h） is proposed. Regarding the addressed scenario, when the propagation link between HAPS and train is blocked by obstacles, a three-dimensional （3-D） geometrical single cylinder spatial-temporal channel model is presented, in which closed form, mathematically tractable space-time correlation functions are obtained. It shows that the correlation functions determined by the 3-D model are of significant difference with those of the conventional 2-D model. Based on the analysis model, the paper derives a realized simulation model using sum-of-sinusoids approach, and applies method of equal areas （MEA） and modified method of equal areas （MMEA） to determine the model parameters. The fitting performance of the simulation model with the analysis one is evaluated by two means-square error （MSE） performance criteria. Finally, numerical simulation results verify the mathematical analysis conclusion, when N ≥21, simulation model has an excellent fitness with the analysis one.
基金This work was supported by the National Natural Science Foundation of China （No.60871037 andNo.61004133） and the Innovation and Technology Fund of Hefei Institutes of Physical Science.
文摘High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a big challenge to FAIMS spectral peak analysis. In this work, a universal and effective model of FAIMS spectral peak profile has been proposed by introducing ion trajectory and loss height. With this model, the influence of the structure of ion drift tube, dispersion voltages, compensation voltages, and carrier gas flow rate on the FAIMS spectral peak characteristics like peak shape, full width at half maximum and peak height is analyzed and discussed. The results show that the influence of different factors on the FAIMS spectral peak profile can be qualitatively described by the model which agrees with the experimental data.
基金the National Natural Science Foundation of China for Distinguished Young Scholars(Grant No.60625102)the State Key Program of the National Natural Science Foundation of China(Grant No.60532030)+1 种基金the National Natural Sciences Foundation of China(Grant No.10377005)the National Safety Major Fundamental Research Program of China(Grant No.61361)
文摘Since mobile networks are not currently deployed on a large scale, research in this area is mostly by simulation. Among other simulation parameters, the mobility model plays a very important role in determining the protocol performance in MANET. Based on random direction mobility model, a high dynamic adaptive mobility network model is proposed in the paper. The algorithms and modeling are mainly studied and explained in detail. The technique keystone is that normal distribution is combined with uniform distribution and inertial feedback control is combined with kinematics, through the adaptive control on nodes speed and prediction tracking on nodes routes, an adaptive model is designed, which can be used in simulations to produce realistic and dynamic network scenarios. It is the adaptability that nodes mobile parameters can be adjusted randomly in threedimensional space. As a whole, colony mobility can show some rules. Such random movement processes as varied speed and dwells are simulated realistically. Such problems as sharp turns and urgent stops are smoothed well. The model can be adapted to not only common dynamic scenarios, but also high dynamic scenarios. Finally, the mobility model performance is analyzed and validated based on random dynamic scenarios simulations.
基金Supported by the Bourse du Conseil Médical de l’hôpital Erasme,Fonds E.et S.Jacobs and Novartis GrantThe CMMI is supported by the European Regional Development Fund and Wallonia
文摘BACKGROUND Acetaminophen overdose is the most frequent cause of drug-induced liver failure in developed countries.Substantial progress has been made in understanding the mechanism of hepatocellular injury,but N-acetylcysteine remains the only effective treatment despite its short therapeutic window.Thus,other hepatoprotective drugs are needed for the delayed treatment of acetaminopheninduced hepatotoxicity.Our interest focused on glycyrrhizin for its role as an inhibitor of high mobility group box 1(HMGB1)protein,a member of the family of damage-associated molecular pattern,known to play an important pathological role in various diseases.AIM To investigate the efficacy of the N-acetylcysteine/glycyrrhizin combination compared to N-acetylcysteine alone in the prevention of liver toxicity.METHODS Eight-week-old C57BL/6J wild-type female mice were used for all our experiments.Mice fasted for 15 h were treated with acetaminophen(500 mg/kg)or vehicle(phosphate-buffered saline)by intraperitoneal injection and separated into the following groups:Glycyrrhizin(200 mg/kg);N-acetylcysteine(150 mg/kg);and N-acetylcysteine/glycyrrhizin.In all groups,mice were sacrificed 12 h following acetaminophen administration.The assessment of hepatotoxicity was performed by measuring plasma levels of alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase.Hepatotoxicity was also evaluated by histological examination of hematoxylin and eosin-stained tissues sections.Survival rates were compared between various groups using Kaplan-Meier curves.RESULTS Consistent with data published in the literature,we confirmed that intraperitoneal administration of acetaminophen(500 mg/kg)in mice induced severe liver injury as evidenced by increases in alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase but also by liver necrosis score.Glycyrrhizin administration was shown to reduce the release of HMGB1 and significantly decreased the severity of liver injury.Thus,the co-administration of glycyrrhizin and N-acetylcysteine was investigated.Administered concomitantly with acetaminophen,the combination significantly reduced the severity of liver injury.Delayed administration of the combination of drugs,2 h or 6 h after acetaminophen,also induced a significant decrease in hepatocyte necrosis compared to mice treated with N-acetylcysteine alone.In addition,administration of N-acetylcysteine/glycyrrhizin combination was associated with an improved survival rate compared to mice treated with only N-acetylcysteine.CONCLUSION We demonstrate that,compared to N-acetylcysteine alone,co-administration of glycyrrhizin decreases the liver necrosis score and improves survival in a murine model of acetaminophen-induced liver injury.Our study opens a potential new therapeutic pathway in the prevention of acetaminophen hepatotoxicity.
基金supported by the Council of Scientific and Industrial Research(CSIR),India,under the SRF scheme(sanction letter No.08/237(0005)/2012-EMR-I)
文摘We have developed a 2D analytical model for the single gate AllnSb/lnSb HEMT device by solving the Poisson equation using the parabolic approximation method. The developed model analyses the device perfomance by calculating the parameters such as surface potential, electric field distribution and drain current. The high mobility of the AlInSb/InSb quantum makes this HEMT ideal for high frequency, high power applications. The working of the single gate AllnSb/InSb HEMT device is studied by considering the variation of gate source voltage, drain source voltage, and channel length under the gate region and temperature. The carrier transport efficiency is improved by uniform electric field along the channel and the peak values near the source and drain regions. The results from the analytical model are compared with that of numerical simulations （TCAD） and a good agreement between them is achieved.
基金funded by the Sino Probe project(Sinoprobe-02-04)
文摘The subduction of the Indian continental lithosphere under the Asian continent caused the uplift of the Tibet Plateau,resulting in the formation of a thickened continental crust twice of the normal value and the crustal shortening of at least 1500 km.Therefore,many models have been proposed to explain the shortening and material transportation mechanism of the Tibetan Plateau.
文摘Short gate-length High Electron Mobility Transistors (HEMTs) have been observed to exhibit kinks in their drain current-voltage (I-V) characteristics. To model this nonlinear effect, we present an effective approach that is easily incorporated into most existing empirical HEMT I-V models. This has been done by modifying the channel length modulation parameter to account for the kink effect. Moreover, the definitions of the left parameters in the original model will not be influenced, and the improved HEMT I-V model enhances its bias range of operation for which accuracy is maintained. The proposed modeling method is validated through DC/ Pulsed I-V as well as large-signal power measurements.
文摘The National University Corporation Tsukuba University of Technology(NTUT)is the only institute of higher education for the hearing and the visually impaired in Japan.In our university,hearing or visually impaired students are studying to be technicians after they graduate,toward social independence.From previous experience of higher education for students with disabilities,effects are increased when modeling is used by the teachers involved in professional education.In the Mechanical Engineering Course,we are using modeling,to match the drawing and shape for beginning students.It includes support for enhancing one's view,and how to draw out the ability of mechanical engineering students for the basics.For students to study Mechanical Design and Drawing,Modeling of Gear Pump,Jack and Globe Valve are easily shown through drawings and the operation of each mechanism through sample drawings in the textbook.It is possible to make an opportunity to think about the machine mechanism.It will be shown by students'works.The assembling of the model triggers the need for form accuracy by making a function,and improves the quality of learning.It is possible that a three-dimensional molding machine can be produced through experiential learning by the model,and modeling with the dimension numerical data.Moreover,it is also embodied in a three-dimensional modeling which results in the image processing programming created.Confirming the improvement of the program through the shape with the quality.In the Department of Synthetic Design,students have chances to realize and self-evaluate from the design of the lamp shade with a complicated shape.In the Faculty of Health Science from Department of Health,high quality teaching of visually-impaired students through the use of bone model teaching materials has become possible in the medical-related courses.
文摘为了精确模拟低温下氮化镓高电子迁移率晶体管(Gallium Nitride high electron mobility transistor,GaN HEMT)的微波噪声性能,提出了一种基于小信号等效电路构建低温噪声模型的方法.利用导纳参数的频率依赖性获取小信号等效电路元件,建立了精确的小信号模型.在此基础上依据Pospieszalski原理对低温噪声源进行表征,特别是栅极泄漏引入的散粒噪声,建立了低温噪声模型.仿真结果表明:在0.2~40 GHz频段,小信号模型的S参数最大误差为2.5%,在2~10 GHz频段噪声模型的四噪声参数最大误差仅在1%以内.其中,低温下栅极泄漏散粒噪声贡献约0.1 K,较于传统方法,新方法具有一定的有效性和更高的准确性.
基金Project supported by the Council of Scientific & Industrial Research(CSIR),India under the Senior Research Fellowship Scheme(No.08/237(0005)/2012-EMR-I)
文摘A compact model is proposed to derive the charge density of the AlInSb/InSb HEMT devices by con- sidering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with applied gate voltage. The proposed model considers the Fermi level dependence of charge density and vice versa. The analytical results generated by the proposed model are compared and they agree well with the experimental results. The developed model can be used to implement a physics based compact model for an InSb HEMT device in SPICE applications.
