Magnetic Field Calculation and Multi-objective Optimization of Axial Flux Permanent Magnet Generator with Coreless Stator Windings

Zhu Jun,Li Shaolong,Song Dandan,Han Qiaoli,Li guanghua 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.4

For the problem that the complexity of 3-D modeling and multi parameter optimization, as well as the uncertainty of the winding factor of axial flux permanent magnet generator with coreless windings. The complex 3-D model was simplified into 2-D analytic model, and an analytical formula for the winding factor that adapting different coreless stator winding is proposed in this paper. The analytical solution for air-gap magnetic fields, no-load back EMF, electromagnetic torque, and efficiency are calculated by using this method. The multiple objective and multivariable optimization of the maximum fundamental and the minimum harmonic content of back EMF are performed by using response surface methodology. The proposed optimum design method was applied to make a generator. The generator was tested and the calculated results are compared with the proposed method, which show good agreements.

Comparative Analysis of Coreless Axial Flux Permanent Magnet Synchronous Generator for Wind Power Generation

Zhu Jun,Li Guanghua,Cao Di,Zhang Zhenyi,Li Shuaihui 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.2

A 90° Halbach permanent magnet array coreless axial fux permanent magnet synchronous generator for wind power generation is compared with a conventional axial fux permanent magnet generator with cut cake type permanent magnet. 2D analytic model of generator is established. The air gap magnetic felds of two generators are analyzed by analytical method, and the air gap magnetic density and harmonic content are analyzed. Then the infuence of diferent parameters on voltage total harmonic distortion is analyzed by changing the pole arc coefcient, air gap length, permanent magnet thickness and number of turns. Two prototypes of generators are manufactured, and the correctness of the simulation results is verifed by experiments.

Optical method for detecting the concentration of sucrose based on plasmonic nanostructures

Zhu Jun,Yin Jinguo 한국탄소학회 2022 Carbon Letters Vol.32 No.2

We report the first observation of Fano resonance in the Y-shaped cavity (YC), demonstrate that the sensitivity of the sensor is as high as 1160 nm/RIU, much higher than that of the aforementioned sensors, and observe that the quality factor and sensitivity of Fano resonance can be adjusted by changing the geometry of the sensor or adding silver nanoparticles. Traditional sucrose detection methods either waste resources or pollute the environment. This work shows that the sensor can be used to detect the concentration of sucrose. In addition, we found that the concentration of sucrose has a linear relationship with its corresponding refractive index. The sensor we designed can easily and rapidly calculate the concentration of a sucrose solution based on the Fano resonance wavelength shift, which is an important first step towards detecting the refractive index of the solution and identify the composition.

Design and Optimization of a New Half Direct-Driven MW-Scale Axial Flux Permanent Magnet Generator for Wind Turbine

Zhu Jun,Nan Huaichun,Guo Xiangwei,Liu Penghui,Du Shaotong,Yang Ming 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

This paper designs a new MW-scale half direct-driven axial flux permanent magnet generator (HDDAFPMG), which incorporates the merits of compact structure and high power density.In order to improve the output voltage quality of the generator,a multi-objective optimization method of parameter hierarchical optimization mechanism and NSGA-II is used to optimize the key design parameters of the generator.By comparing the performance of initial and optimization model using Finite Element Method (FEM), it is found that the output voltage quality of the optimization model is significantly improved.In addition,the Halbach permanent magnet (PM) array is used to decrease the total harmonic distortion (THD) of voltage waveform and decrease the thickness of back iron.It is concluded that the generator with 60° magnetized Halbach PM array can decrease the THD of voltage waveform decreases from 2.27% to 0.46% and decrease the thickness of back iron from 36 mm to 15 mm, which is reduced by 58.33%.

SIGNALING EFFECT AND THE INFLUENCE OF GENRES: MOVIE CONSUMPTION ON CHINESE ONLINE VIDEO PLATFORMS

Zhujun Li,Haodong Gu,Ning Chen 글로벌지식마케팅경영학회 2020 Global Marketing Conference Vol.2020 No.11

Glucosinolates in Chinese Brassica Vegetables and Its Regulatory Mechanisms

Zhujun Zhu,Huasen Wang,Xinjuan Chen,Jing Yang,Xiaolei Ni 한국원예학회 2008 한국원예학회 기타간행물 Vol.- No.-

The Effects of Tai Chi Intervention on Healthy Elderly by Means of Neuroimaging and EEG: A Systematic Review

Pan, Zhujun,Su, Xiwen,Fang, Qun,Hou, Lijuan,Lee, Younghan,Chen, Chih C.,Lamberth, John,Kim, Mi-Lyang Frontiers Media S.A. 2018 FRONTIERS IN AGING NEUROSCIENCE Vol.10 No.-

<P>Aging is a process associated with a decline in cognitive and motor functions, which can be attributed to neurological changes in the brain. Tai Chi, a multimodal mind-body exercise, can be practiced by people across all ages. Previous research identified effects of Tai Chi practice on delaying cognitive and motor degeneration. Benefits in behavioral performance included improved fine and gross motor skills, postural control, muscle strength, and so forth. Neural plasticity remained in the aging brain implies that Tai Chi-associated benefits may not be limited to the behavioral level. Instead, neurological changes in the human brain play a significant role in corresponding to the behavioral improvement. However, previous studies mainly focused on the effects of behavioral performance, leaving neurological changes largely unknown. This systematic review summarized extant studies that used brain imaging techniques and EEG to examine the effects of Tai Chi on older adults. Eleven articles were eligible for the final review. Three neuroimaging techniques including fMRI (<I>N</I> = 6), EEG (<I>N</I> = 4), and MRI (<I>N</I> = 1), were employed for different study interests. Significant changes were reported on subjects' cortical thickness, functional connectivity and homogeneity of the brain, and executive network neural function after Tai Chi intervention. The findings suggested that Tai Chi intervention give rise to beneficial neurological changes in the human brain. Future research should develop valid and convincing study design by applying neuroimaging techniques to detect effects of Tai Chi intervention on the central nervous system of older adults. By integrating neuroimaging techniques into randomized controlled trials involved with Tai Chi intervention, researchers can extend the current research focus from behavioral domain to neurological level.</P>

중국어 미래문법형태 `회(會)`의 기원과 변화과정에 대한 고찰

염죽균 ( Lian Zhujun ) 한국중국어문학회 2016 中國文學 Vol.89 No.-

Bybee et al.(1994:265-266)은 중국어 표준말의 미래문법형태 `會`(會미래)가 능력양태에서 발원했다고 주장한다. 그리고 이러한 변화 유형에 대해 `능력 〉 근원적 가능성 〉 의도 〉 미래`의 변화경로를 가정했다. 하지만 세계 언어에서 이러한 변화과정은 드물기 때문에 관련 언어에 대해 깊이 있는 고찰을 선행한 후에 검증해야 한다. 따라서 본고는 선행연구를 다시 정리하고 역사자료를 상세하게 고찰하며 중국어의 會미_래가 이러한 변화과정을 겪으면서 발전해 왔는지를 검증하고자 한다. 본고의 논증 과정은 다음과 같다. 우선, 會_미래는 가능성을 표현하는 `會`(會_가능)와 긴밀한 관계가 있기 때문에 2.1에서 會가능의 출현 시기, 기원, 그리고 생성과정을 설명한다. 한대(漢代), 육조(六朝) 시기의 자료에 대한 고찰을 통해 會_가능은 한대, 육조시기에 이미 출현하였고 그 기원은 `회합(會合)`의미를 표현하는 `會`라고 분석했다. 會_가능의 생성과정은 `회합하다` 〉 `부합하다`/ `만나다`... 〉 `가능성이 있다`이다. 그 후에 2.2에서는 각 시기에서 사용된 會_가능의 의미적, 통사적 특징을 고찰한다. 한대-당오대(漢代-唐五代) 시기, 송원(宋元) 시기, 명청-민국(明淸-民國) 시기로 나누어 분석하였다. 각 시기의 특징을 종합하여 필자는 會_가능이 한대-당오대 시기에 이미 가지고 있던 두 가지 용법(용법a 필연적 결과, 용법b 미래에 대한 추측)이 각각 `사건-지향적인 가능성`과 `객관적인 가능성`을 표현한다는 것을 밝혔다. 이 두 용법의 변화 방향은 `사건-지향적인 가능성` 〉 `객관적인 가능성`이다. 또한 역사자료에 따르면 송대 이후에 `객관적인 가능성`은 동시에 두 가지 방향으로 변화한 것을 확인할 수 있다. 하나는 `주관적인 양태`로 변화하는 방향, 다른 하나는 `미래문법형태`로 변화하는 방향이다. 會_가능의 변화과정은 會_미래의 생성경로를 포함하고 있다. 즉, `회합하다` 〉 `부합하다`/ `만나다`... 〉 `사건-지향적인 가능성` 〉 `객관적인 가능성` 〉 `미래문법형태`이다. 따라서 본고의 고찰에 의하면 중국어의 미래문법형태 `會`의 변화과정은 Bybee et al.(1994:265-266)에서 가정한 것과 다르다는 것을 발견할 수 있었다.

‘가능’의미를 표현하는 ‘會’의 기원과 그 변화경로에 대한 고찰

廉竹鈞(Lian Zhujun) 중국어문학연구회 2016 중국어문학논집 Vol.0 No.100

This paper discusses the origin and the development path of the ‘hui(會)’ which expresses ‘possibility’ in Chinese. After looking through historical corpus and analysing previous studies, we arrive at the following conclusions: (1) The origin of the ‘hui(會)’ expressing ‘possibility’ is the original meaning of ‘hui(會)’―that is ‘to meet with (something)’ ―but not ‘ability’, because the ‘possibility’ meaning appeared among Han Dynasty and the Six Dynasties, while the ‘ability’ meaning appeared among Tang Dynasty and Song Dynasty. (2) There may have been two development paths from ‘to meet with (something)’ to ‘possibility’. One is ‘to meet with (something)’→‘to accord with’→‘possibility’ through two consecutive metaphor changes, and the other is ‘to meet with (something)’→‘to meet with (a certain situation)’→‘possibility’ through metaphor and reanalysis.

“V起來”動趨結構中身體部位賓語的位置問題

廉竹鈞(Lian Zhujun) 중국어문학연구회 2022 중국어문학논집 Vol.- No.136

This paper discusses the positioning of body part nouns when they appear with a “V+qilai(起來)”verb-tendency construction as an object. There are two possible sequences for them, one is “V+起+O+來” and the other is “把+O+V+起來”. First, we analysed why the“V+起來”construction and body part objects cannot take the sequence of “V+起來+O”. Body part nouns have low categoriality, which means they are not autonomous, discourse-salient entities in a discourse in general. According to the information structure rules, if the position of a sentence element is near the end of the sentence, there is a higher possibility for the sentence element to have new and important information. However, the low-categoriality of body part nouns makes it inappropriate to appear at the end of the sentence. Then, based on linguistic data, we analysed the factors which affect the selection between “V+起+O+來” and “把+O+V+起來” , and arrived at the following conclusions: There are several syntactic, semantic, and pragmatic factors that influence speakers to choose between “V+起+O+來” and “把+O+V+起來”. On the syntactic level, since the adverb “dou(都)” means “all” or “even”, the adverb “ye(也)” which means “even” can only be related to a sentence element on the left side of them. If these two words are related to the body part object, then only the “把+O+V+起來” sequence is possible because it is only through this sequence that the body part object can be lifted to the left of them. On the semantic level, if the body part object is highly related to the V, then the “V+起+O+來” sequence is preferred. When two elements have a close semantic relationship, they tend to appear together in high frequency. It is a common phenomenon in languages where zero or short coding is preferred for those meanings and functions occurring more frequently, while for those occurring rarely, overt, and long coding is preferred. On the pragmatic level, because of the Economical Principle of Language, the rules of information structure, and the Principle of Head Proximity, speakers will prefer to choose the “把+O+V+起來” sequence. Aside from the factors mentioned above, due to a trend of the “把+O+V+起來” sequence being used more often in the verb/adjective-tendency construction, speakers will choose this sequence even if there are no obvious syntactic, semantic, or pragmatic factors.