Identification of crystal orientation for turbine blades with anisotropy materials

A novel approach to identify the crystal orientation of turbine blades with anisotropy materials is proposed. Based on enhanced mode basis, with the main advantages of its efficiency, accuracy and general applicability, the blade vibration mode of each order is linearly constructed by several specified mode shapes, which are obtained from the considered turbine blade with specified crystal orientations correspondingly. Then, a surrogate model based on Kriging method is introduced for constructing the condensed perturbed matrix of stiffness in order to improve the efficiency even further. The constructed surrogate model allows to perform the modal analysis of turbine blades with arbitrary crystal orientations in higher efficiency, due to the fact that the elements of condensed perturbed matrix of stiffness are considered in construction of the surrogate model rather than concerning the perturbation of all the elements of the initial stiffness matrix for the blade. Genetic algorithm is finally employed to optimize the defined fitness functions in order to identify the crystal orientation angles of turbine blades. Several corresponding examples demonstrated the accuracy, efficiency and general applicability of the proposed method

Development of a Composite Technique for Preconditioning of 41Cr4 Steel Used as Gear Material: Examination of Its Microstructural Characteristics and Properties

Commercial 41Cr4 (ISO standard) steel was treated by a composite technique. An intermediate layer was introduced firstly at the 41Cr4 steel surface by traditional carburizing and nitriding. Then a hard Cr coating was brush-plated on the intermediate layer. Finally, the coating layer was modified by high current pulsed electron beam (HCPEB), followed by quenching and subsequent tempering treatment. The microstructure, mechanical properties, and fracture behavior were characterized. The results show that a nanocrystalline Cr coating is formed at the 41Cr4 steel surface by the treatment of the new composite technique. Such nanocrystalline Cr coating has acceptable hardness and high corrosion resistance performance, which satisfies the demands of the gears working under high speed and corrosive environment. The composite process proposed in this study is considered as a new prospect method due to the multifunction layer design on the gear surface

Science and technology innovation and practice of major national science and technology special project of coalbed methane in coal mining area

The scientific and technological innovation system formed by the national major oil and gas projects has the characteristics of “new nationwide innovation system”, and the system of scientific and technological projects has the characteristics of “whole process, multi-stage and full life cycle”. During the 11th Five-Year Plan period and 13rd Five-Year Plan period, major national oil and gas projects have continuously supported scientific and technological breakthroughs and technological innovations in basic theories, key technologies and complete sets of equipment for the development and utilization of coalbed methane. Members of the national major projects of oil and gas projects and project implementation unit, paying great efforts, aim to taking the national major projects of oil and gas as an great opportunity, to enhance the level of coal mine area of coalbed methane of science and technology innovation and form the leading industry of coal mining area of coal bed methane research and development of science and technology innovation system, to fully support the realization of key scientific research goals of major national oil and gas projects. Coal mining area coal bed methane grograms have formed a series of major landmark achievements, built a series of industry innovation platform, comprehensively stired the technological progress and industrial development of coal-bed methane industry in coal mining areas of China, and effectively promoted the construction of the coal-bed methane industry in China. Combined with the organization and implementation of the project (subject)/demonstration project and the characteristics of the coal industry, we have systematically summarize the exploration and practice of CBM technological innovation in national major special coal mine area and formed a national major special project of science and technology, which is “guided by national investment, dominated by enterprise investment, highly integrated with industry, university, research and application, and continuously leading the technological progress of the industry”. In establishing and perfecting the organization and management institutions, continue to strengthen the special management specification, continue to play a role of cohesive ties, coordination to promote the scientific research management innovation, promote the development and use fusion to form coal mining area of coalbed methane from the concrete experience of science and technology innovation practice

A comprehensive database of Duchenne and Becker muscular dystrophy patients (0–18 years old) in East China

BACKGROUND: Currently, there is no cure for Duchenne and Becker muscular dystrophies (DMD/BMD). However, clinical trials with new therapeutic strategies are being conducted or considered. A comprehensive database is critical for patient recruitment and efficacy evaluation. China has the largest population, yet, no comprehensive database for DMD/BMD is available. Our study registered the data of the DMD/BMD patients in East China. METHODS: A modified registry form of Remudy (http://www.remudy.jp/) was applied to Chinese DMD/BMD patients through the outpatient clinic at Children’s Hospital of Fudan University, Shanghai during the period of August 2011 to December 2013. The data included geographic distribution of patients, age at diagnosis, clinical manifestation, genetic analysis and treatment status. RESULTS: 194 DMD and 35 BMD patients were registered. Most patients lived in East China, namely Jiangsu province, Anhui province, Zhejiang province, Jiangxi province, Shanghai, Fujian province and Shandong province. All individuals aged less than 18 years (age limit to a children’s hospital). Diagnosis was made for a majority of patients during the age of 3–4 (16.6%) and 7–8 (14.8%) years old. Exon deletion was the most frequent genetic mutations (65.5% and 74.3%) followed by point mutations (14.4% and 11.4%), duplications (9.8% and 8.6%) and small insertion/deletion (9.3% and 2.9%) for DMD and BMD, respectively. 82.5% of DMD registrants were ambulatory, and all the BMD registrants were able to walk. 26.3% of DMD registrants have been treated with steroids. Cardiac functions were examined for 46.4% DMD boys and 45.7% BMD boys and respiratory functions were examined for 18.6% DMD boys and 14.3% BMD boys. Four boys with abnormal cardiac function were prescribed for treatment with cardiac medicine. 33.2% of DMD patients are eligible for exon skipping therapy, and among them 9.2% and 4.3% patients are eligible for skipping exon 51 and 53, respectively. CONCLUSIONS: The database is the first linking accurate genetic diagnosis with clinical manifestation and treatment status of dystrophinopathy patients in East China. It provides comprehensive information essential for further patient management, especially for promotion of international cooperation in developing experimental therapies such as exon skipping and read-through of nonsense mutations targeting a subgroup of DMD patient population

Clinical and Genetic Characteristics of Mitochondrial Encephalopathy Due to FOXRED1 Mutations: Two Chinese Case Reports and a Review of the Literature

Background: As one of the assembly factors of complex I in the mitochondrial respiratory chain, FOXRED1 plays an important role in mitochondrial function. However, only a few patients with mitochondrial encephalopathy due to FOXRED1 defects have been reported.Methods: Two Chinese patients with mitochondrial encephalopathy due to mutations in FOXRED1 were identified through trio whole-exome sequencing. The clinical presentation, laboratory data, brain imaging findings, and genetic results were collected and reviewed. All previously reported cases with FOXRED1-related mitochondrial encephalopathy were collected using a PubMed search, and their data were reviewed.Results: Two patients presented with severe neurodevelopmental delay, epilepsy, high lactic acid levels, and remarkable diffuse brain atrophy and polycystic encephalomalacia during early infancy. Trio whole-exome sequencing revealed compound heterozygous variants in both patients: one case harbored a c.606_607delAG frameshift variant and a c.1054C&amp;gt;T (p.R352W) variant. At the same time, the other carried a novel c.352C&amp;gt;T (p.Q118X) variant and a reported c.1054C&amp;gt;T (p.R352W) variant. To date, nine patients have been reported with FOXRED1 defects, including our two cases. The most common presentations were neurodevelopment delay (100%), epilepsy (80%), poor feeding (30%), and vision loss (20%). Multisystem involvement comprised cardiovascular dysfunction (30%), abnormal liver function (20%), and hypoglycemia (10%). The neuroimaging results ranged from normal to severe cerebral atrophy and polycystic encephalomalacia in early infancy. Eleven pathogenic variants in FOXRED1 have been reported, comprising six missense variants, two non-sense variants, two frameshift variants, and one splice variant; among these the c.1054C&amp;gt;T (p.R352W) and c.612_615dupAGTG (p.A206SfsX15) variants are more common.Conclusion:FOXRED1-related mitochondrial disorders have high clinical and genetic heterogeneity. Our study expanded the clinical and genetic spectrum of FOXRED1 defects. Early infantile onset and progressive encephalopathy are the most common clinical presentations, while the variants c.1054C&amp;gt;T (p.R352W) and c.612_615dupAGTG (p.A206SfsX15) may be critical founder mutations.</jats:p

Bayesian Uncertainty Identification of Model Parameters for the Jointed Structures with Nonlinearity

Jointed structures in engineering naturally perform with some of nonlinearity and uncertainty, which significantly affect the dynamic characteristics of the structural system. In this paper, the method of Bayesian uncertainty identification of model parameters for the jointed structures with local nonlinearity is proposed. Firstly, the nonlinear stiffness and damping of the joints under the random excitation are represented with functions of excitation magnitude in terms of the equivalent linearization. The process of uncertainty identification is separated from the representation of local nonlinearity. In this way, the dynamic behavior of the joints is penetratingly characterized instead of ascribing the nonlinearity to uncertainty. Secondly, a variable-expanded Bayesian (VEB) method is originally proposed to identify the mixed of aleatory and epistemic uncertainties of model parameters. Different from traditional Bayesian identification, the aleatory uncertainties of model parameters are identified as one of the most important parts rather than only measurement noise of output. Notablely, a series of intermediate variables are introduced to expand the parameter with aleatory uncertainty in order to overcome the difficulty of establishing the likelihood function. Moreover, a 3-DOF numerical example is illustrated with case studies to verify the proposed method. The influence of observed sample size and prior distribution selection on the identification results is tested. Furthermore, an engineering example of the jointed structure with rubber isolators is performed to show the practicability of the proposed method. It is indicated that the computational model updated with the accurately identified parameters with both nonlinearity and uncertainty has shown the excellent predictive capability