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- Linear matrix inequality (2)
- Motion estimation (2)
- Robust stability (2)
- Algorithm (1)
- Angle tracking (1)
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- Approaching maneuver (1)
- Attitude (1)
- Bearing estimation (1)
- Bidirectional associative memory neural networks (1)
- Bipartite hypergraph (1)
- Block matching (1)
- Brightness (1)
- Browser-oriented data extraction (1)
- Bubble (1)
- Commutation failure (1)
- Corporate governance (1)
- Coupling (1)
- Data extraction model (1)
- Detergent (1)
- Diameter (1)
- Differential scanning calorimetry (DSC) (1)
- Direction of arrival (1)
- Direction-ofarrival (DOA) estimation (1)
- Edge alignment (1)
- Emulsion stability (1)
- Energy consumption and management (1)
- Extended Kalman filter (1)
- Fast block matching (1)
- Financial prediction (1)
- Finite element method (1)
Articles 1 - 28 of 28
Full-Text Articles in Engineering
A New Calibration Method For Low Cost Mems Inertial Sensor Module, Sheng-Chih Shen, Chia-Jung Chen, Hsin-Jung Huang
A New Calibration Method For Low Cost Mems Inertial Sensor Module, Sheng-Chih Shen, Chia-Jung Chen, Hsin-Jung Huang
Journal of Marine Science and Technology
This paper presents a new calibration method to overcome the challenges of MEMS inertial sensors for underwater navigation. The MEMS inertial sensor module is composed of an accelerometer, a gyroscope and a circuit of signal process. For navigation estimation, it is easy to be influenced by errors which come from MEMS inertial sensors. In general, the sources of error can be categorized into two groups, deterministic type and stochastic type. The former primarily includes bias errors, misalignment and nonlinearity; the latter contains temperature effect and signal drifting. Subsequently, the linearity calibration is used to modify the deterministic error and the …
Fast Block Motion Estimation With Edge Alignment On H.264 Video Coding, Chi-Han Chuang, Chien-Hua Su, Shyi-Chyi Cheng
Fast Block Motion Estimation With Edge Alignment On H.264 Video Coding, Chi-Han Chuang, Chien-Hua Su, Shyi-Chyi Cheng
Journal of Marine Science and Technology
This paper presents a novel block matching scheme with edge alignment strategy on H.264 video coding, which uses multiple references and multiple block sizes for motion estimation in order to improve the rate-distortion performance. In H.264, the computational complexity is linearly dependent on the number of allowed reference frames and block sizes using the full exhaustive search. Many fast block-matching algorithms reduce the computational complexity of motion estimation by carefully designing the search patterns with different shapes or sizes which have significant impact on the search speed and distortion performance. However, the search speed and the distortion performance conflict often …
The Performance Of Indium Tin Oxide Films Deposited On Plastic Substrate Applied For Solar-Cell Buoy, Chien-Kun Wang, Jyh-Jier Ho, Sung-Jen Nien, Yuang-Tung Cheng, William Lee, Chih-Chiang Lu, Bao-Shun Yau, Hsing-Wang Tsai, Chung-Cheng Chang
The Performance Of Indium Tin Oxide Films Deposited On Plastic Substrate Applied For Solar-Cell Buoy, Chien-Kun Wang, Jyh-Jier Ho, Sung-Jen Nien, Yuang-Tung Cheng, William Lee, Chih-Chiang Lu, Bao-Shun Yau, Hsing-Wang Tsai, Chung-Cheng Chang
Journal of Marine Science and Technology
In this paper, we report the indium tin oxide (ITO) films deposited on the polyethyene terephthalate (PET) substrate, which surface is treated with detergent solution. The ITO films are deposited on room temperature by direct current (DC) magnetron sputtering from a ceramic target of a 90% In-10% Sn alloy. The deposited opto-electric ITO films on PET with detergent treatment are 83.4% average visible transparency, and 5.8 × 10-4 Ω-cm resistivity, respectively. And then, we use the spin coating to form the polymer solar cell. Under optimal conditions of surface treatment and film deposition, the experimental result shows 2.12% of the …
Signal Subspace Transformation For Direction-Of-Arrival Estimation Of Wideband Sources In Near Field, Lena Chang
Signal Subspace Transformation For Direction-Of-Arrival Estimation Of Wideband Sources In Near Field, Lena Chang
Journal of Marine Science and Technology
A novel adaptive signal subspace transformation for direction-of-arrival (DOA) estimation of wideband sources in the near-field is proposed in this paper. The method is composed of two transformations: signal subspace focusing (SSF) and far-field transformation (FFT). SSF aligns the signal subspaces for different frequencies in the bandwidth of the sources based on focusing matrices. FFT transforms the near-field steering vector to be the far-field steering vector with same direction-of-arrival (DOA) allocation. By the way, we simplify the location estimation of wideband sources in the near-field to be narrowband sources in the far field. The proposed method can track the DOAs …
The Study On The Asymptotic Profile And The Flow Patterns In Front Of A Long Bubble Through A Circular Tube, Cheng-Hsing Hsu, Chia-Chuan Kuo, Ching-Chuan Chang, Kuang-Yuan Kung
The Study On The Asymptotic Profile And The Flow Patterns In Front Of A Long Bubble Through A Circular Tube, Cheng-Hsing Hsu, Chia-Chuan Kuo, Ching-Chuan Chang, Kuang-Yuan Kung
Journal of Marine Science and Technology
Department of Civil Engineering, Army Academy, Chung-Li, Taoyuang, Taiwan, R.O.C
Sidescan Sonar Image Processing:Correcting Brightness Variation And Patching Gaps, Yet-Chung Chang, Shu-Kun Hsu, Ching-Hui Tsai
Sidescan Sonar Image Processing:Correcting Brightness Variation And Patching Gaps, Yet-Chung Chang, Shu-Kun Hsu, Ching-Hui Tsai
Journal of Marine Science and Technology
Sidescan sonar data are typically presented as gray level images. However, sidescan images often show striking variations in brightness. These variations, caused by the sonar beam pattern and the constantly changing attitude of the towfish, make the images difficult to read as pictures of the seabed. This reduces the utility of the images for marine geologists. In this paper, the effects of the sonar beam pattern across the swath are corrected using a normalization process based on the average signal intensity for each grazing angle. Noise along the track, which is generally caused by changes in the attitude of the …
The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang
The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang
Journal of Marine Science and Technology
In MEMS capacitive microphone design, it is very critical to get highest yielding rate and sensitivity as the two major factors dominate structure design of microphone. The centralpost MEMS microphone is introduced in this paper to differentiate from traditional fixed membrane boundary microphone since the construction is simple and only few masks are required in the process so that the yielding can be greatly enhanced. Thus, it is necessary to find the relationship between the sensitivity and dimension of the diameter of the membrane. The main research steps described in this paper include using CoventorWarer to develop one analysis model …
An Algorithm For Predicting Attitudes Of Floating Bodies With Arbitrary Configurations In Liquids, Jiann-Lin Chen, Chun-I Chen, Li-Ming Chu
An Algorithm For Predicting Attitudes Of Floating Bodies With Arbitrary Configurations In Liquids, Jiann-Lin Chen, Chun-I Chen, Li-Ming Chu
Journal of Marine Science and Technology
A robust and efficient algorithm is proposed to quasiunsteadily predict attitudes of floating bodies with arbitrary configurations. Numerical techniques for accuracy and computing time saving are addressed. A floating cylinder was modeled as a benchmark, by theoretical and experimental approaches, to validate the developed program. Attitudes of two kinds of floating bodies, which are a body composed of multiple objects and a submarine-like submersible, were simulated to show the feasibility of the present algorithm. Interestingly, the simulated results of a slender body, such as a cylinder or a submersible, show that the attitude variation is very sensitive to the longitudinal …
Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung
Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung
Journal of Marine Science and Technology
The batter properties of sponge cake with the addition of γ-polyglutamic acid (PGA) at different levels (0.05, 0.1, 0.5 gkg-1, w/w) was evaluated. The viscosity, emulsion stability and foam stability increased at the addition of 0.5 gkg-1 PGA level. PGA caused significant declines in the differential scanning calorimetry (DSC) enthalpy, onset and peak temperatures of ice-melting transition of sponge cake. Sponge cakes manufactured with 0.5 gkg-1 PGA addition were in general lighter on crumb color and white index than the control. Scanning electron microscopy showed that sponge cake with the addition of 0.1 and 0.5 gkg-1 PGA exhibited microstructures having …
On State-Feedback Controller Synthesis For A Class Of Second-Order Nonlinear Systems With Uncertainties, Jenq-Lang Wu, Chee-Fei Yung
On State-Feedback Controller Synthesis For A Class Of Second-Order Nonlinear Systems With Uncertainties, Jenq-Lang Wu, Chee-Fei Yung
Journal of Marine Science and Technology
This paper presents a constructive method to design stabilizing controllers for a class of second-order uncertain nonlinear systems whose input parts may vanish at the origin. A sufficient condition for the existence of stabilizing state feedback controllers is provided. Under the small control property, a formula is proposed for constructing continuous stabilizing feedback laws. In the case that the small control property does not hold, another formula for constructing continuous state feedback controllers, with small control magnitude near the origin, to achieve robust practical stability is presented.
Hamilton Decomposition Of Complete Bipartite 3-Uniform Hypergraphs, Jirimutu Jirimutu, Jul Wang
Hamilton Decomposition Of Complete Bipartite 3-Uniform Hypergraphs, Jirimutu Jirimutu, Jul Wang
Journal of Marine Science and Technology
The problem of finding a Hamilton decomposition of the complete 3-uniform hypergraph 3 Kn has been solved for n ≡ 2(mod 3), n ≡ 4(mod 6) [2], n ≡ 1(mod 6), n ≡ 0(mod 3) (for 3 , K I n − the complete 3-uniform hypergraph minus a 1- factor) [5]. In this paper, we give the concept of the bipartite hypergraphs and find a Hamilton decomposition of the complete bipartite hypergraph 3 Km,m for m be prime.
Steady-State Characteristics Analysis Of Deep-Sea Running Mechanism With Planetary Gear Wheel Based On Articulated Steering Radius, Ya-Li Feng, Yi-Ting Kang, Wen-Ming Zhang, Jie Zhang
Steady-State Characteristics Analysis Of Deep-Sea Running Mechanism With Planetary Gear Wheel Based On Articulated Steering Radius, Ya-Li Feng, Yi-Ting Kang, Wen-Ming Zhang, Jie Zhang
Journal of Marine Science and Technology
Steady-state characteristics analysis for the deep-sea running mechanism with planetary gear train which is designed to adapt to complex terrain in the deep-sea hydrothermal sulfide and rich-cobalt incrustation survey area is based on articulated steering radius. The articulated steering radius formula of the deep-sea running mechanism is derived from the geometric relationship, considering the wheel side slip angle. Based on the formula, three types of steering steady-state characteristic analysis, understeer, neutral steer and oversteer, are made for the mechanism. Steering simulation analysis of the running mechanism with planetary gear is conducted in ADAMS software with different speed. In the process …
Numerical Optimization Of A Three-Chamber Muffler Hybridized With A Side Inlet And A Perforated Tube By Sa Methodm, Min-Chie Chiu
Numerical Optimization Of A Three-Chamber Muffler Hybridized With A Side Inlet And A Perforated Tube By Sa Methodm, Min-Chie Chiu
Journal of Marine Science and Technology
Research on new techniques of multi-chamber mufflers equipped with a side inlet and an internal non-perforated tube has been well addressed and developed; however, the research work of multi-chamber mufflers in conjunction with side inlet and internal perforated tubes which may efficiently increase the acoustical performance is rare. Therefore, the main purpose of this paper is to not only analyze the sound transmission loss (STL) of three-chamber side mufflers with a perforated tube but also to optimize their best design shape under a limited space. In this paper, both the generalized decoupling technique and plane wave theory in solving the …
Vector Quantization Based On Steady-State Memetic Algorithm, Chien-Min Ou
Vector Quantization Based On Steady-State Memetic Algorithm, Chien-Min Ou
Journal of Marine Science and Technology
A novel memetic algorithm (MA) for the design of vector quantizers (VQs) is presented in this paper. The algorithm uses steady-state genetic algorithm (GA) for the global search and K-means algorithm for the local improvement. As compared with the usual MA using the generational GA for global search, the proposed MA dramatically reduces the computational time for VQ training. In addition, it attains a near global optimal solution, and its performance is insensitive to the selection of initial codewords. Numerical results show that it can save more than 70% of computation time while maintaining a comparable performance as previous MA
Vfife Method Applied For Offshore Template Structures Upgraded With Damper System, Po-Yen Chang, Hsien Hua Lee, Guo-Wei Tseng, Pei-Yin Chung
Vfife Method Applied For Offshore Template Structures Upgraded With Damper System, Po-Yen Chang, Hsien Hua Lee, Guo-Wei Tseng, Pei-Yin Chung
Journal of Marine Science and Technology
In this study, a plane frame element derived from vector form intrinsic finite element (VFIFE) method is adapted and applied to study the dynamic responses of an offshore template platform subject to wave forces. Furthermore, this vector form intrinsic finite element is modified in order to incorporate a visco-elastic material, which has excellent energyabsorption ability, to a damping device installed in the structural system to mitigate the wave-induced vibration. The method adopted in this study is a scheme similar to the one by updating the geometry of the structural system during the calculation of each time step, which is also …
The Role Of Non-Financial Features Related To Corporate Governance In Business Crisis Prediction, Fengyi Lin, Deron Liang, Wing-Sang Chu
The Role Of Non-Financial Features Related To Corporate Governance In Business Crisis Prediction, Fengyi Lin, Deron Liang, Wing-Sang Chu
Journal of Marine Science and Technology
Recent outbreak of corporate financial crises worldwide has brought attention to the need for a new international financial architecture which rests on crisis prediction and crisis management. It is therefore both desirable and vital to explore new predictive techniques for providing early warnings aganist bankruptcy. Financial data have been widely used by researchers to predict financial distress or business crisis, but few studies exploit the use of non-financial indicators related to corporate governance to construct business crisis prediction model. This article introduces into the field of business crisis prediction model based on a combination of both financial and corporate governance …
Design And Application Of An Image-Processing-Based Fuzzy Autopilot For Small-Boat Approaching Maneuvers, Sin-Der Lee, Ching-Yaw Tzeng, Young-Zehr Kehr, Chih-Kai Kang, Chi-Chun Huang
Design And Application Of An Image-Processing-Based Fuzzy Autopilot For Small-Boat Approaching Maneuvers, Sin-Der Lee, Ching-Yaw Tzeng, Young-Zehr Kehr, Chih-Kai Kang, Chi-Chun Huang
Journal of Marine Science and Technology
This paper presents an image-processing-based fuzzy autopilot scheme for accomplishing small-boat approaching maneuvers in a harbor environment. In the proposed approach, two canvas targets are arranged in cascade on the quayside to form a leading line. The targets are detected by a charge coupled device (CCD) camera mounted on the bow of the boat, and their geometric centers are computed by a Hue- and Saturation-based image-processing scheme. The autopilot system calculates the current heading deviation and tracking deviation angles of the boat by analyzing the displacements of the target centers relative to the CCD center line. These angles are then …
Numerical Assessment Of A Space-Constrained Venting System With Multi-Chamber Plug Mufflers By Ga Method, Chiu Min-Chie, Chang Ying-Chun
Numerical Assessment Of A Space-Constrained Venting System With Multi-Chamber Plug Mufflers By Ga Method, Chiu Min-Chie, Chang Ying-Chun
Journal of Marine Science and Technology
Recently, research on new techniques of single-chamber plug silencers has been addressed. However, the assessment of a multi-chamber plug muffler’s optimal shape design within a constrained space as well as a pressure-drop limit which are mostly concerned with the necessity of operation and system venting in practical engineering work was rarely tackled. Therefore, this paper will not only analyze the sound transmission loss (STL) of a space-constrained multi-chamber plug muffler but also optimize the best design shape under a specified pressure drop. In this paper, the generalized decoupling technique and plane wave theory used to solve the coupled acoustical problem …
Direct Mapping Ovsf-Based Transmission Scheme For Underwater Acoustic Multimedia Communication, Chin-Feng Lin, Jiang-Yao Chen, Ya-Ju Yu, Jung-Ting Yan, Shung-Hyung Chang
Direct Mapping Ovsf-Based Transmission Scheme For Underwater Acoustic Multimedia Communication, Chin-Feng Lin, Jiang-Yao Chen, Ya-Ju Yu, Jung-Ting Yan, Shung-Hyung Chang
Journal of Marine Science and Technology
We would like to express our appreciation to the people that provided their help during this study. We also extend our appreciation to Dr. Chang-tai Shih, Visiting Professor of National Taiwan Ocean University from the Canadian Mu- seum of Nature, for his critical review and comments on the manuscript. This study was financially supported by a grant (NSC94-2313-B-019-018 and 94AS-14.1.1-FA-F1(16)) from the National Science Council of the Republic of China and the Fisheries Agency, Council of Agriculture, Taiwan, R.O.C.
A Delay-Dependent Approach To Robust Stability For Uncertain Hybrid Bidirectional Associative Memory Neural Networks With Time-Varying Delays, Chien-Yu Lu, Koan-Yuh Chang, Hsun-Heng Tsai, Wen-Jer Chang
A Delay-Dependent Approach To Robust Stability For Uncertain Hybrid Bidirectional Associative Memory Neural Networks With Time-Varying Delays, Chien-Yu Lu, Koan-Yuh Chang, Hsun-Heng Tsai, Wen-Jer Chang
Journal of Marine Science and Technology
This paper performs a global robust stability analysis of a particular class of hybrid bidirectional associative memory time-varying delayed neural network with norm-bounded timevarying parameter uncertainties. The activation functions are assumed to be globally Lipschitz continuous. Globally delay-dependent robust stability criteria are derived in the form of linear matrix inequalities by introducing relaxation matrices which, when chosen properly, produce a less conservative result. Two numerical examples are given to illustrate the significant improvement obtained in the conservativeness of the delay bound.
Strain Analysis Of Vapor Chamber Heat Spreaders, Yu-Hsun Hung, Shung-Wen Kang, Wan-Chun Tsai
Strain Analysis Of Vapor Chamber Heat Spreaders, Yu-Hsun Hung, Shung-Wen Kang, Wan-Chun Tsai
Journal of Marine Science and Technology
Vapor chamber is a cooling device with phase change phenomena. It not only provides high heat transfer coefficient but also removes hot spot. During working of vapor chamber, the buckle force and vapor pressure could lead to deformation. It is a popular way that pillars are set up to reduce deformation. This paper presents a three-dimensional finite element analysis for the vapor chamber by ANSYS software program. Four pillars with two kinds of designs are built into vapor core in order to avoid deformation of the vapor chamber. The results appear that pillars inside vapor chamber are good to reduce …
On Design Of Browser-Oriented Data Extraction System And The Plug-Ins, Jui-Yuan Su, Der-Johng Sun, I-Chen Wu, Lung-Pin Chen
On Design Of Browser-Oriented Data Extraction System And The Plug-Ins, Jui-Yuan Su, Der-Johng Sun, I-Chen Wu, Lung-Pin Chen
Journal of Marine Science and Technology
Web data extraction systems currently not only extract data on web pages but also need to navigate to the target correctly. Most traditional web data extraction systems extract URLs directly from web pages, and then access next pages using the extracted URLs. This data extraction approach is herein called the URL-oriented data extraction approach in this paper. However, currently, more and more web pages use script functions, such as JavaScript, to access next pages and may hide URLs inside these functions, making it difficult to extract URLs. In order to solve this problem, a new data extraction approach, named the …
Novel Algorithms For Tracking Multiple Targets, Sheng-Yun Hou, Hsien-Sen Hung, Shun-Hsyung Chang, Jeng-Cheng Liu
Novel Algorithms For Tracking Multiple Targets, Sheng-Yun Hou, Hsien-Sen Hung, Shun-Hsyung Chang, Jeng-Cheng Liu
Journal of Marine Science and Technology
In this paper, two novel angle tracking algorithms are proposed for tracking multiple targets using an array of sensors with known locations. First, we present an extended Kalman particle filter (EKPF) which is capable of determining the direction-of-arrival (DOA) angles using a single snapshot of data during the interval between each time step. The proposed EKPF algorithm combines particle filtering with the extended Kalman filter (EKF) in order to prevent sample impoverishment during its resampling process. Next, we present a robust Kalman filter (RKF) tracking algorithm intended to improve tracking success rates of other existing algorithms for the case of …
A Delay-Dependent Approach To Robust Stability For Uncertain Stochastic Neural Networks With Time-Varying Delay, Chien-Yu Lu, Chin-Wen Liao, Koan-Yuh Chang, Wen-Jer Chang
A Delay-Dependent Approach To Robust Stability For Uncertain Stochastic Neural Networks With Time-Varying Delay, Chien-Yu Lu, Chin-Wen Liao, Koan-Yuh Chang, Wen-Jer Chang
Journal of Marine Science and Technology
This paper investigates the global delay-dependent robust stability in the mean square for uncertain stochastic neural networks with time-varying delay. The activation functions are assumed to be globally Lipschitz continuous. Based on a linear matrix inequality approach, globally delay-dependent robust stability criterion is derived by introducing some relaxation matrices which, when chosen properly, lead to a less conservative result. Two numerical examples are given to illustrate the effectiveness of the method.
Fast Block Matching Using Minkowski's Inequality, Jim Zong-Chang Lai, Yi-Ching Liaw, Shih-An Fong
Fast Block Matching Using Minkowski's Inequality, Jim Zong-Chang Lai, Yi-Ching Liaw, Shih-An Fong
Journal of Marine Science and Technology
In this paper, we present a fast block matching algorithm by making use of the Minkowski’s inequality. Combined with other fast block matching algorithms, our method can further reduce the computational complexity significantly with little PSNR degradation. Compared to the full search block matching algorithm, our approach can reduce the computing time by a factor of 6.4 to 21.5. Compared to MSEQ, which is a wellknown block matching algorithm preserving global optimality, our method can further reduce the corresponding computing time in average by 32.4%. The combination of our algorithm and the predictive search area approach for block motion estimation …
Estimation Model Of Transformer Iron Loss Using Neural Network, Tai-Ken Lu, Chien-Ta Yeh, Min-Doon Dirn
Estimation Model Of Transformer Iron Loss Using Neural Network, Tai-Ken Lu, Chien-Ta Yeh, Min-Doon Dirn
Journal of Marine Science and Technology
When we want to calculate the transformer iron loss in operation, in addition to considering the nonlinear hysteretic phenomenon of transformer itself and the natural unbalanced characteristic, the actual situation that the transformer is operated under three phase unbalance state should also be considered. This results in very non-regular change of the transformer iron loss, and the accuracy of the polynomial model that is commonly used to estimate the iron loss of the transformer in the past is thus reduced. Since neural network has parallel processing capability, which can process highly nonlinear function problem, hence, in this study, we try …
Optimal Heating And Energy Management For Slabs In A Reheating Furnace, Wei-Hsin Chen, Mu-Rong Lin, Tzong-Shyng Leu
Optimal Heating And Energy Management For Slabs In A Reheating Furnace, Wei-Hsin Chen, Mu-Rong Lin, Tzong-Shyng Leu
Journal of Marine Science and Technology
Optimal heating for slabs in a reheating furnace is investigated numerically to aid in managing energy consumption of the reheating furnace in a hot strip mill, where an arctangent function is applied as the heating curve. Particular attention is paid to the relationship among the temperature uniformity, discharging target temperature and retention time of the slabs. The results indicate that the temperature difference between the slab surface and the core increases rapidly in the initial period and the maximum value of the temperature difference is close to the inflection point of the heating curve. After that, the internal temperature tends …
Effect Of Commutation Failures On Torsional Vibrations Of A Turbine Generator Nearby An Hvdc Link, Chi-Hshiung Lin
Effect Of Commutation Failures On Torsional Vibrations Of A Turbine Generator Nearby An Hvdc Link, Chi-Hshiung Lin
Journal of Marine Science and Technology
For an HVDC system, it is studied the torsional vibrations induced on the inverter side turbine generators due to a rectifier side ac faults. It is found there may be up to several times difference in the torsional torques induced at the turbine shafts and blades for the same fault, depending on the inverter commutation behavior. Further, if a single-phase-to-ground fault takes place with the commutation failure, it might cause a more serious impact on the turbine generator unit than a threephase-to-ground fault without commutation failure.