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Search Results: 1 - 10 of 6202 matches for " Haiwen Lan "
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Research on the Transient Power Characteristics of the Inverter for Yun-Guang UHVDC  [PDF]
Chengjun Xia, Haiwen Lan, Kun Men, Guokai Liang
Journal of Power and Energy Engineering (JPEE) , 2014, DOI: 10.4236/jpee.2014.29025

During the transient period of large-disturbance of the received power grid, the power features of the inverter are of great important for the security and stability of the system. The research before is defective in that the constant control mode assumption and the rough HVDC simulation model. The paper establishes the PSCAD/EMTDC model for Yun-Guang EHVDC system, and analysis the transient real power and the reactive power of the inverter. With the analysis of logic for control mode, the author also introduces the physical processes of the peak of the reactive power. At last, the paper puts forward several strategies for suppressing the peak of the dynamic reactive power and real power recovery acceleration.

Phytochemical Compositions, Antioxidant Properties, and Colon Cancer Antiproliferation Effects of Turkish and Oregon Hazelnut  [PDF]
Haiwen Li, John W. Parry
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.210153
Abstract: Roasted and raw Turkish and Oregon hazelnuts were examined. Whole nuts, skins, and skinless nuts of both hazelnut varieties were tested for fat contents, fatty acid profiles. Hazelnut and other byproducts were extracted with 50% ace- tone and examined for total phenolic contents (TPC), antioxidant activities against the peroxyl (ORAC) and DPPH radicals, and were also administered in vitro to the human colon cancer HT-29 cell line to determine antiproliferative effects. The Turkish hazelnuts contained over 65% total oil while the Oregon roasted variety contained 43.8%. The primary fatty acid in both was oleic acid (18:1n-9) comprising 76.7 g/100 g oil in the Oregon variety and 83.3 g/100 g oil in the Turkish variety. The TPC were 91.4 and 102.16 mg gallic acid equivalents/ g sample for the Turkish roasted hazelnut skin and Oregon roasted hazelnut skin respectively, at least 30-folds as high as the hazelnut without skin. Turkish roasted hazelnut skin had the highest ORAC value of 1166.27 Trolox equivalents (TE) mmol/g sample (TE mmol/g), it is 38 times as high as the Oregon roasted hazelnut no skin which as a value of 30.2 TE mmol/g sample. The range of ED50 of DPPH? is from 118.22 to 0.075 mg sample equivalents/ mL among the samples, Oregon roasted hazelnut skin and Turkish raw hazelnut no skin exhibit the weakest and strongest ability to reduce DPPH? respectively. At 6 mg/mL media Oregon roasted hazelnut skin extract significantly inhibited the growth of the HT-29 cells by 96h following 4 days of treatment, and no effect was seen from the Turkish roasted skinned hazelnut extract. The Turkish raw hazelnut had significantly higher antioxidant activities compared to the Oregon roasted variety which may be explained by chemical changes during heating or possibly the total oil to flour ratio.
A Study of the Teaching of ESL Writing in Colleges in China
Haiwen Mo
International Journal of English Linguistics , 2012, DOI: 10.5539/ijel.v2n1p118
Abstract: In China, ESL teaching constitutes an important part of higher education and ESL writing is a required skill for non-English majors in colleges and universities. However, the teaching of college English writing is unsatisfactory and problematic. The author did a survey on the teaching of ESL writing in five universities in China by using the methods of questionnaire, interview and sample collection. The results of the survey indicate that the students’ deficiency in English writing is due to personal and instructional reasons, such as ineffective teaching, students’ lack of interest in writing, students’ poor linguistic competence, students’ lack of the cultural knowledge of the target language and so on. In the teaching of college English Writing, the teacher should boost students’ motivation, integrate reading with writing, and provide effective feedback to the students.
A Newton method for simultaneous reconstruction of an interface and a buried obstacle from far-field data
Haiwen Zhang,Bo Zhang
Mathematics , 2012, DOI: 10.1088/0266-5611/29/4/045009
Abstract: This paper is concerned with the inverse problem of scattering of time-harmonic acoustic waves from a penetrable and buried obstacles. By introducing a related transmission scattering problem, a Newton iteration method is proposed to simultaneously reconstruct both the penetrable interface and the buried obstacle inside from far-field data. A main feature of our method is that we do not need to know the type of boundary conditions on the buried obstacle. In particular, the boundary condition on the buried obstacle can also be determined simultaneously by the method. Finally, numerical examples using multi-frequency data are carried out to illustrate the effectiveness of our method.
A novel integral equation for scattering by locally rough surfaces and application to the inverse problem
Haiwen Zhang,Bo Zhang
Mathematics , 2013,
Abstract: This paper is concerned with the direct and inverse acoustic or electromagnetic scattering problems by a locally perturbed, perfectly reflecting, infinite plane (which is called a locally rough surface in this paper). We propose a novel integral equation formulation for the direct scattering problem which is defined on a bounded curve (consisting of a bounded part of the infinite plane containing the local perturbation and the lower part of a circle) with two corners. This novel integral equation can be solved efficiently by using the Nystrom method with a graded mesh introduced previously by Kress and is capable of dealing with large wavenumber cases. For the inverse problem, we propose a Newton iteration method to reconstruct the local perturbation of the plane from multiple frequency far-field data, based on the novel integral equation formulation. Numerical examples are carried out to demonstrate that our reconstruction method is stable and accurate even for the case of multiple-scale profiles.
On the Evaluation of Performance System Incorporating “Green Credit” Policies in China’s Financial Industry  [PDF]
Lan Xu
Journal of Financial Risk Management (JFRM) , 2013, DOI: 10.4236/jfrm.2013.22005

The main work of this paper is aimed, through utilizing the two-stage optimization theory, to estimate the green distance functions and Malmquist green growth indexes for the China’s main commercial banks and relevant financial institutions, and to further set up an overall appraisal index system to assess their performance in implementing the “Green Credit” principles. The paper also analyzes effects of the “Green Credit” policies influential on revenue achievements, as well as performs a decomposition analysis of the above impacts. The carry-outs of the paper may serve as useful references and guiding means in achievingChina’s economic transitional strategies of sustainable development.

Research on the Technology Enterprise Performance Evaluation Index System  [PDF]
Lan Fu
iBusiness (IB) , 2013, DOI: 10.4236/ib.2013.53B002

The purpose of this essay is to design a framework of a performance evaluation system which is subject to the characteristics of China technology enterprises. It based on the analyzing the principles and significance of the performance evaluation system of technology enterprises. The framework will promote the standardize management of technology enterprises of China.

3-D Modelling of the Confederation Bridge Using Data of Full Scale Tests  [PDF]
Lan Lin
Open Journal of Civil Engineering (OJCE) , 2013, DOI: 10.4236/ojce.2013.33B004

Long-span bridges are special structures that require advanced analysis techniques to examine their performance. This paper presents a procedure developed to model the Confederation Bridge using 3-D beam elements. The model was validated using the data collected before the opening of the bridge to the public. The bridge was instrumented to conduct fullscale static and dynamic tests. The static tests were to measure the deflection of the bridge pier while the dynamic tests to measure the free vibrations of the pier due to a sudden release of the static load. Confederation Bridge is one of the longest reinforced concrete bridges in the world. It connects the province of Prince Edward Island and the province of New Brunswick in Canada. Due to its strategic location and vital role as a transportation link between these two provinces, it was designed using higher safety factors than those for typical highway bridges. After validating the present numerical model, a procedure was developed to evaluate the performance of similar bridges subjected to traffic and seismic loads. It is of interest to note that the foundation stiffness and the modulus of elasticity of the concrete have significant effects on the structural responses of the Confederation Bridge.

Research on the Development Strategy of Logistics Firms in China  [PDF]
Lan Wang
Open Journal of Social Sciences (JSS) , 2014, DOI: 10.4236/jss.2014.29042

The logistics industry has attracted wide attention as an important industry that supports economic development. Most of Chinese logistics enterprises are transferred from traditional transportation and warehousing business. Their information integration and mining capacity is insufficient. The basis of weak competitiveness of the traditional logistics industry needs to be improved. By analyzing the driven factors of modern logistics industry, the paper further discusses Chinese logistics enterprises’ problems and analyzes the case of X company to describe the business strategy of modern logistics firms.

Research on the Construction of the Emergency Logistics System in the Large State-Owned Enterprises  [PDF]
Lan Fu
Open Journal of Social Sciences (JSS) , 2014, DOI: 10.4236/jss.2014.29010

The purpose of this essay is to discuss some issues about the government how to improve the construction of the infrastructures, transportation system and communication system and how to enhance the capability of resisting natural disaster as the disaster comes. Emergent logistics information system not only can help the power group to collect information and forecast the future disaster but also has the function of decision-making and supporting. Furthermore the emergency logistics information system can assist the power group to decrease the loss from the disaster.

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