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In this paper, a technology computer-aided design (TCAD) model of a silicon carbide (SiC) insulated-gate bipolar transistor (IGBT) has been calibrated against previously reported experimental data.
(b) (a) Fig. 2. a) TCAD calibration results of the forward characteristics, IC-VCE, compared to experimental data of a 22 kV SiC IGBT [7]. b) Charge-carrier lifetime-dependent breakdown voltage characteristics of the four theoretical SiC IGBTs with 20-50 kV blocking voltage capability (τA,LOW = 1 μs vs. τA,HIGH = 100 μs).
Summary A 4H-SiC IGBT TCAD model has been calibrated against experimental data and has been used to widely investigate static performance of high voltage SiC IGBTs (20-50 kV).
The calculation indicates that a conduction loss energy reduction of 30 % may be achieved by using 30 kV SiC IGBTs.
Furthermore, the wide range simulation data may serve as input to future converter evaluation studies in various high-power applications.

Vehicle weight reduction is an important measure to reduce fuel consumption, drop the pollutant emissions and noise and vibration reduction.
It is also a way of vehicle weight reduction such as adopting the new technology such as bonding.
Dow Chemical To set up a joint venture with Turkey AKSA with mainly the production of carbon fiber(AKSA is the world's largest acrylic fiber manufacturer, got involved in the carbon fiber industry in 2008) 7 2011 Japan's Teijin large carbon fiber company Develop the mass production of carbon fiber l frame instead of stee Data sources: official website and related statistical agencies. 2 The main reason analysis In this paper, on the basis of extensive investigation , the main reasons have been made a detailed analysis , and the next five aspects can be summarized: .First of all, at the present stage, it is difficult for our car enterprises to fundamentally solve the contradiction between the weight and safety.
Automobile weight reduction will affect on safety performance.
Doctoral Fund of Ministry of education project” Automobile Full Life Cycle Evaluation of Energy Saving and Emission Reduction Based on Technological Change” （20090161110008）.

Erosion Behavior of Silicon Nitride with Graded Microstructure Dae-Soon Lim 1,a, Jong-In Park1,b, Dong-Phill Lim 1,c, Byung-Dong Han 2,d, Dong-Soo Park2,e 1 Department of Material Science and Engineering, Korea University, 1, 5-ga, Anam-dong, sungbuk-gu, Seoul 136-701, Korea 2 Ceramic Materials Group, KIMM, 66 Sangnam-dong, Chang-Won, Kyong-Nam, Korea a dslim@korea.ac.kr, bmaru203@hanmail.net, cnoonimp@empal.com, d cera72@kmail.kimm.re.kr, epds1590@kmail.kimm.re.kr Keywords: Graded microstructure, Erosion, Silicon nitride, Oxidation, Carbothermal reduction Abstract Silicon nitride has been considered as candidate tribological material due to their excellent mechanical and thermal properties.
Carbothermal reduction treatment was performed to the reduce oxygen content within the powder during this procedure Heat treatment with tube furnace was performed using 0.1 l/min flow rate nitrogen atmosphere for 10h at 1450℃.
Results and discussions A graded structure was obtained by an additional carbothermal reduction treatment.
Data shows that oxide is more easily formed in fine surface compared to coarse surface.

The simulated results show a very good agreement with the measured data.
In order to improve the model predictive accuracy, the FMEP model used in this model based on the actual friction data on bench.
The results of engine performance has been plotted and compared with actual testing data.
The data show a good agreement between simulation result and actual test as illustrated in Figure 8.
The discrepancy of between simulation data versus actual measurement recorded at approximately 0.8%.

The off-chip accesses are performed by the data fetch an data transfer two operations and the execution time Toff for Woff is sum of the time Toff1 for the data transfer which depends on the frequency fint and the timeToff2 for the data fetch which depends on the frequency fext.
The execution time T of a task can be calculated as: where is the ratio between the data transfer time and the data fetch time and is set to be 0.35 based on the experimental results.
According to the on-chip workload and off-chip workload, the system energy consumption for a task at frequency combination Fn is given as: where is the power of the system for the standby state at Fn. , and are system power at Fn for on-chip workload, data transfer and data fetch respectively.
The relationship between energy consumption of PMP and the ratio ρ at different frequency combinations We review the energy model for PMP and set the power parameters according to the experimental data.
Simulation result The proposed algorithms DVFS_AFC and DVFS_TFC are simulated by the energy model for PMP whose power parameters fit the experimental data.

Shape Optimization One of key aspects of sustainability is reduction of primary material consumption.
Aggregated LCA results: Aggregated impact data for specific life cycle phases construction are presented in Table 1.
Table 1 Aggregated impact data of construction life phase The higher water consumption of V3 (subtle HPC frame) in comparison to V2 (precast RC frame) in construction life phase (Table 1) is connected with production of lightening elements from wood shavings concrete.
Fig. 9 Aggregated data – primary energy consumption per unit area of all alternatives in MJ Figure 10 presents the comparison of assessed alternatives. 100% is represented by V1 (monolithic RC frame structure from C30/37).
Fig. 10 Aggregated data – primary energy consumption per unit area of all alternatives in MJ.

This study adopted a self-administered questionnaire method to obtain real time data for the analysis of behavioral practices.
Reliability is a statistical measure of the reproducibility or stability of data gathered by the survey instrument.
The Ford questionnaire was first distributed to all employees from different management level in the department and the data obtained were analyzed.
The objective of the structured interview was to ensure and support the empirical data accumulated from the survey.
These findings were drawn from the data analyzed in year 2012, as shown in Fig. 1.

The results proved that predictions based on our mathematical model were agreed with the experimental data comparatively.
The burr volume reduction ΔV within process time Δt can be expressed as follows:
Therefore, the volume of metal removal capacity from the workpiece calculated by Eq. 2 is larger than the actual burr volume reduction.
In M-ECD process, the deburring time t increase considerably when the processing current is less than 0.1A, and the reduction in deburring time is not evident while the probabilities of discharge and short circuit will increase when the processing current is more than 0.4 A.
(2) The rate of burr height reduction is initially high and it reduces gradually with processing time.

Considering the engineering design margin, noise reduction is amplified relevantly, the actual noise reduction of air outlet is determined as 85 dB(A).
Flow area of the third stage silencer: S3=9×11×2.6×0.145=37.3 m2, air volume measured on site is 169.11 m3/s, so flow velocity of the third stage muffler: Placing whose value is 4.5 into Eq. 9: By the data calculated upon, the regenerative noise is within the target range in the end of noise control, the design is reasonable.
The Calculation of the Total Amount of Noise Reduction.
The values of noise reduction of the muffler and the target values of noise reduction are shown in the Table 5.
Table 5 The Values of Noise Reduction of The Muffler And The Target Values of Noise Reduction Center frequency [Hz] 125 250 500 lK 2K 4K Amount of noise reduction [dB] First stage 4.4 4.4 4.4 4.4 4.4 4.4 Second stage 17.5 19.3 17.5 15.1 9.6 6.8 Third stage 11.5 24.3 22.1 18.8 17.7 13.9 Total amount of noise reduction [dB] 33.4 48 44 38.3 31.7 25.1 Minimum value of noise reduction[dB] 25.6 26.5 27.5 20.9 13.5 10.4 According to Table 5, the amount of noise reduction of each center frequency is more than the minimum value of noise reduction, so muffler design can satisfy the requirement of noise reduction.

Patil and Hodges [14] did the work of LCO in high aspect ratio wings and state that LCO data becomes increasingly complex with the increase in speed.
Furthermore, data acquisition systems, DAQ were used in gathering signals from measurement sources and digitizing the signal for storage and analysis.
The data acquisition has been used to record the data during wind tunnel test.
The test has been repeated several times to find if there are major irregularities in the data obtained.
The data obtained might be served as a reference in future aerospace research areas.