An Improved Method of Maximum Power Point Tracking Strategy for Wind Power Conversion System

CHEN Ran,CHEN Jie,CHEN Jia-wei,CHEN Zhi-hui,GONG Chun-ying,YAN Yang-guang 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

The turbine speed loop adjustment is the key link of the designing of the controller for the fixed pitch variable speed wind energy conversion systems (WECS). Because of the strong nonlinear, big inertia and mechanical damping characteristics, it’s difficult to designing the controller of the wind power systems. In this paper, a small signal model is present, and based on the analyzing; a wind turbine speed loop regulator is designed. Then, a method of tracking the peak power conversion system is proposed, which is independent of the turbine parameters and air density. At last, simulation system is built, and the results of the simulation experiments show that, the performance of the controller algorithm meet the requirements of the MPPT without wind measurement.

Liposomal honokiol, a potent anti-angiogenesis agent, in combination with radiotherapy produces a synergistic antitumor efficacy without increasing toxicity

Jia Hu,Li Liu,Xiang Chen,Ping Chen,Guang-li Yang,Wen-li Hou,Ming-hai Tang,Fan Zhang,Xian-huo Wang,Xia Zhao,Yu-quan Wei,Li-juan Chen 생화학분자생물학회 2008 Experimental and molecular medicine Vol.40 No.6

Honokiol is an active compound purified from magnolia that has been shown to induce cell differentiation, apoptosis, and anti-angiogenesis effects, as well as an enhancement in tumor growth delay in combination with chemotherapeutic agents in several mouse xenograft models. Our goal was to investigate the radiosensitization effect of honokiol on lung carcinoma. The radiosensitization effect of liposomal honokiol in Lewis lung carcinoma cells (LL/2) was analyzed using an in vitro clonogenic survival assay. For an in vivo study, Lewis lung carcinoma-bearing C57BL/6 mice were treated with either liposomal honokiol at 25 mg/kg or 5 Gy of single tumor radiation, or a combination of both over 12 days of treatment. The tumor growth delay and the survival time were evaluated. In addition, histological analysis of tumor sections was performed to examine changes by detecting the microvessel density and apoptosis in tumor tissues. In the clonogenic survival assay, LL/2 cells treated with IC50 Lipo-HNK for 24 h showed a radiation enhancement ratio of 1.9. After 12 days of combination treatment, the tumor volume decreased 78% and produced an anti-tumor activity 1.3-fold greater than a predicted additive effect of honokiol and radiation alone. This combination treatment also caused an 8.7 day delay in tumor growth. The cell cycle distribution and histological analysis demonstrated that liposomal honokiol has an anti-tumor effect via inducing apoptosis and inhibiting angiogenesis. Liposomal honokiol can enhance tumor cell radiosensitivity in vitro and in vivo, indicating that radiotherapy combined with liposomal honokiol can lead to greater anti-tumor efficacy. Honokiol is an active compound purified from magnolia that has been shown to induce cell differentiation, apoptosis, and anti-angiogenesis effects, as well as an enhancement in tumor growth delay in combination with chemotherapeutic agents in several mouse xenograft models. Our goal was to investigate the radiosensitization effect of honokiol on lung carcinoma. The radiosensitization effect of liposomal honokiol in Lewis lung carcinoma cells (LL/2) was analyzed using an in vitro clonogenic survival assay. For an in vivo study, Lewis lung carcinoma-bearing C57BL/6 mice were treated with either liposomal honokiol at 25 mg/kg or 5 Gy of single tumor radiation, or a combination of both over 12 days of treatment. The tumor growth delay and the survival time were evaluated. In addition, histological analysis of tumor sections was performed to examine changes by detecting the microvessel density and apoptosis in tumor tissues. In the clonogenic survival assay, LL/2 cells treated with IC50 Lipo-HNK for 24 h showed a radiation enhancement ratio of 1.9. After 12 days of combination treatment, the tumor volume decreased 78% and produced an anti-tumor activity 1.3-fold greater than a predicted additive effect of honokiol and radiation alone. This combination treatment also caused an 8.7 day delay in tumor growth. The cell cycle distribution and histological analysis demonstrated that liposomal honokiol has an anti-tumor effect via inducing apoptosis and inhibiting angiogenesis. Liposomal honokiol can enhance tumor cell radiosensitivity in vitro and in vivo, indicating that radiotherapy combined with liposomal honokiol can lead to greater anti-tumor efficacy.

AtHAP3b Plays a Crucial Role in the Regulation of Flowering Time in Arabidopsis during Osmotic Stress

Chen, Nai-Zhi,Zhang, Xiu-Qing,Wei, Peng-Cheng,Chen, Qi-Jun,Ren, Fei,Chen, Jia,Wang, Xue-Chen Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.6

The HAP complex has been found in many eukaryotic organisms. HAP recognizes the CCAAT box present in the promoters of 30% of all eukaryotic genes. The HAP complex consists of three subunits - HAP2, HAP3 and HAP5. In this paper, we report the biological function of the AtHAP3b gene that encodes one of the HAP3 subunits in Arabidopsis. Compared with wild-type plants, hap3b-1 and hap3b-2 mutants exhibited a delayed flowering time under long-day photoperiod conditions. Moreover, the transcription levels of FT were substantially lower in the mutants than in the wild-type plants. These results imply that AtHAP3b may function in the control of flowering time by regulating the expression of FT in Arabidopsis. In a subsequent study, AtHAP3b was found to be induced by osmotic stress. Under osmotic stress conditions, the hap3b- 1 and hap3b-2 mutants flowered considerably later than the wild-type plants. These results suggest that the AtHAP3b gene plays more important roles in the control of flowering under osmotic stress in Arabidopsis.

Chemical constituents from Viburnum fordiae Hance and their anti-inflammatory and antioxidant activities

Jia Chen,Jianhua Shao,Chunchao Zhao,Jie Shen,Ziling Dong,Wenyan Liu,Min Zhao,Judi Fan 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.6

Three new neolignans, fordianoles A-C (1–3),characterized as (7S,8R)-4-hydroxy-3,30,50-trimethoxy-80,90-dinor-8,40-oxyneolignan-7,70,9-triol, (7R,8R)-4-hydroxy-3,30,50-trimethoxy-80,90-dinor-8,40-oxyneolignan-7,70,9-triol, and (7R,8R)-4-hydroxy-3,30,50-trimethoxy-8,40-oxyneolignan-7,9,90-triol-70-one, together with an unusual c-lactone,3-(3,4-dihydroxyphenyl)-4-pentanolide (4), andtwenty-five known compounds (5–29) were isolated fromthe aerial parts of Viburnum fordiae Hance. Their structuresincluding absolute configurations were determined byspectroscopic and chemical methods. Among them, compounds6, 7, 11–15, 17–28 were isolated from the Viburnumgenus for the first time. The anti-inflammatory and antioxidantactivities of all compounds were evaluated in vitro. Compounds 15, 19, 20 and 29 showed significant inhibitoryactivity on NO production in RAW264.7 cells stimulated byLPS with IC50 values ranging from 8.60 to 13.92 lM. Meanwhile, compounds 1–4, 15, 19, 20, 22, 23, 25, 26 and29 exhibited varying antioxidant activities through DPPH,ABTS free radical scavenging and FRAP assays.

A Novel Molecular Grading Model: Combination of Ki67 and VEGF in Predicting Tumor Recurrence and Progression in Non-invasive Urothelial Bladder Cancer

Chen, Jun-Xing,Deng, Nan,Chen, Xu,Chen, Ling-Wu,Qiu, Shao-Peng,Li, Xiao-Fei,Li, Jia-Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Purpose: To assess efficacy of Ki67 combined with VEGF as a molecular grading model to predict outcomes with non-muscle invasive bladder cancer (NMIBC). Materials: 72 NMIBC patients who underwent transurethral resection (TUR) followed by routine intravesical instillations were retrospectively analyzed in this study. Univariate and multivariate analyses were performed to confirm the prognostic values of the Ki67 labeling index (LI) and VEGF scoring for tumor recurrence and progression. Results: The novel molecular grading model for NMIBC contained three molecular grades including mG1 (Ki67 $LI{\leq}25%$, VEGF $scoring{\leq}8$), mG2 (Ki67 LI>25%, VEGF $scoring{\leq}8$; or Ki67 $LI{\leq}25%$, VEGF scoring > 8), and mG3 (Ki67 LI > 25%, VEGF scoring > 8), which can indicate favorable, intermediate and poor prognosis, respectively. Conclusions: The described novel molecular grading model utilizing Ki67 LI and VEGF scoring is helpful to effectively and accurately predict outcomes and optimize personal therapy.

Dose-Dependent Associations between Wine Drinking and Breast Cancer Risk - Meta-Analysis Findings

Chen, Jia-Yan,Zhu, Hong-Cheng,Guo, Qing,Shu, Zheng,Bao, Xu-Hui,Sun, Feng,Qin, Qin,Yang, Xi,Zhang, Chi,Cheng, Hong-Yan,Sun, Xin-Chen Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Purpose: To investigate any potential association between wine and breast cancer risk. Materials and Methods: We quantitatively assessed associations by conducting a meta-analysis based on evidence from observational studies. In May 2014, we performed electronic searches in PubMed, EmBase and the Cochrane Library to identify studies examining the effect of wine drinking on breast cancer incidence. The relative risk (RR) or odds ratio (OR) were used to measure any such association. Results: The analysis was further stratified by confounding factors that could influence the results. A total of twenty-six studies (eight case-control and eighteen cohort studies) involving 21,149 cases were included in our meta-analysis. Our study demonstrated that wine drinking was associated with breast cancer risk. A 36% increase in breast cancer risk was observed across overall studies based on the highest versus lowest model, with a combined RR of 1.0059 (95%CI 0.97-1.05) in dose-response analysis. However, 5 g/d ethanol from wine seemed to have protective value from our non-linear model. Conclusions: Our findings indicate that wine drinking is associated with breast cancer risk in a dose-dependent manner. High consumption of wine contributes to breast cancer risk with protection exerted by low doses. Further investigations are needed for clarification.

Mitigating Cache Pollution Attack in Information Centric Mobile Internet

( Jia Chen ),( Liang Yue ),( Jing Chen ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.11

Information centric mobile network can significantly improve the data retrieving efficiency by caching contents at mobile edge. However, the cache pollution attack can affect the data obtaining process severely by requiring unpopular contents deliberately. To tackle the problem, we design an algorithm of mitigating cache pollution attacks in information centric mobile network. Particularly, the content popularity distribution statistic is proposed to detect abnormal behavior. Then a probabilistic caching strategy based on abnormal behavior is applied to dynamically maintain the steady-state distribution for content visiting probability and achieve the purpose of defense. The experimental results show that the proposed scheme can achieve higher request hit ratio and smaller latency for false locality content pollution attack than the CacheShield approach and the baseline approach where no mitigation approach is applied.

Design and Implementation on Spatial Science and Technology Information Database of CSI

Chen, Xiu Wan,Deng, Zheng Quan,Lu, Zhi Gao,Ma, Jia,Lin, Jia Yuan,Zhang, Wen Jiang,Luo, Tianfu,Liu, Baofu 대한원격탐사학회 2000 International Symposium on Remote Sensing Vol.16 No.1

Remote Sensing technology, which is characterized by producing imagery an multi-platform, different temporal and spatial resolution, has greatly improved mankind's capability of acquisition, processing and application of spatial information. The increase of spatial data sources and the development, applications and industrialization of spatial information technology are urging the need of spatial data sharing and exchanging. Based an a brief introduction an the China Spatial Information Network (CSI) and its database system, the CSI Spatial Science and Technology Information Database (SSTID) management system was designed and implemented in this paper.

Enhanced Performance of Solution‐Processed TESPE‐ADT Thin‐Film Transistors

Chen, Liang‐,Hsiang,Hu, Tarng‐,Shiang,Huang, Peng‐,Yi,Kim, Choongik,Yang, Ching‐,Hao,Wang, Juin‐,Jie,Yan, Jing‐,Yi,Ho, Jia‐,Chong,Lee, Cheng‐,Chung,Chen WILEY‐VCH Verlag 2013 Chemphyschem Vol.14 No.12

<P><B>Abstract</B></P><P>A solution‐processed anthradithiophene derivative, 5,11‐bis(4‐triethylsilylphenylethynyl)anthradithiophene (TESPE‐ADT), is studied for use as the semiconducting material in thin‐film transistors (TFTs). To enhance the electrical performance of the devices, two different kinds of solution processing (spin‐coating and drop‐casting) on various gate dielectrics as well as additional post‐treatment are employed on thin films of TESPE‐ADT, and <I>p</I>‐channel OTFT transport with hole mobilities as high as ∼0.12 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> are achieved. The film morphologies and formed microstructures of the semiconductor films are characterized in terms of film processing conditions and are correlated with variations in device performance.</P>

Reliability and thermal fatigue life prediction of solder joints for advanced automotive microelectronics

Jia-Chen Gao,Jae B. Kwak 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8

With the development of the automotive industry, the number of automotive electronic components is growing rapidly. This leads to new requirements for reliability of the automotive electronics. Especially, for difficult operating environments, such as engine compartment of the car, extreme thermal cycles, and long holding time, where prediction of the fatigue life of the component is particularly important. In this study, thermal fatigue life prediction models for two packages are proposed: TSOP over BGA, and flip chip with BGA. The overall deformation of the two packages was analyzed using Moiré fringes, and was found to be consistent with simulation results. The reliability of the model was verified by comparing thermal shock results and simulation results. Then, the fatigue life of the component under thermal cycles was predicted using the model. The overall component life of the BGA with flip chip package was 818 cycles. For TSOP over BGA this was 1005 cycles, but the shortest life of the BGA was 725 cycles, which may result in the failure of the entire component. The fatigue life prediction using different models is helpful to assess and optimize components at the early stage of product development.