Mode Switching Smooth Control of Transient Process of Grid-Connected 400 ㎐ Solid-State Power Supply System

Jun-Jie Zhu,Zi-Ling Nie,Yin-Feng Zhang,Yi Han 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.6

The mode-switching control of transient process is important to grid-connected 400 ㎐ solid-state power supply systems. Therefore, this paper analyzes the principle of on-grid and islanding operation of the system with or without local loads in the grid-connected process and provides a theoretical study of the effect of different switching sequences on the mode-switching transient process. The conclusion is that the mode switch (MS) must be turned on before the solid-state switch (STS) in the on-grid process and that STS must be turned off before the MS in the off-grid process. A strategy of mode-switching smooth control for transient process of the system is proposed, including its concrete steps. The strategy utilizes the average distribution of peak currents and the smooth adjustment of peak currents and phases to achieve a no-shock grid connection. The simulation and experimental results show that the theoretical analysis is correct and that the method is effective.

Mode Switching Smooth Control of Transient Process of Grid-Connected 400 Hz Solid-State Power Supply System

Zhu, Jun-Jie,Nie, Zi-Ling,Zhang, Yin-Feng,Han, Yi The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.6

The mode-switching control of transient process is important to grid-connected 400 Hz solid-state power supply systems. Therefore, this paper analyzes the principle of on-grid and islanding operation of the system with or without local loads in the grid-connected process and provides a theoretical study of the effect of different switching sequences on the mode-switching transient process. The conclusion is that the mode switch (MS) must be turned on before the solid-state switch (STS) in the on-grid process and that STS must be turned off before the MS in the off-grid process. A strategy of mode-switching smooth control for transient process of the system is proposed, including its concrete steps. The strategy utilizes the average distribution of peak currents and the smooth adjustment of peak currents and phases to achieve a no-shock grid connection. The simulation and experimental results show that the theoretical analysis is correct and that the method is effective.

An Optimal Random Carrier Pulse Width Modulation Technique Based on a Genetic Algorithm

Jie Xu,Zi-Ling Nie,Jun-Jie Zhu 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.2

Since the carrier sequence is not reproducible in a period of the random carrier pulse width modulation (RCPWM) and a higher harmonic spectrum amplitude is likely to affect the quality of the power supply. In addition, electromagnetic interference (EMI) and mechanical vibration will appear. To solve these problems, this paper has proposed an optimal RCPWM based on a genetic algorithm (GA). In the optimal modulation, the range of the random carrier frequency is taken as a constraint and the reciprocal of the maximum harmonic spectrum amplitude is used as a fitness function to decrease the EMI and mechanical vibration caused by the harmonics concentrated at the carrier frequency and its multiples. Since the problems of the hardware make it difficult to use in practical engineering, this paper has presented a hardware system. Simulations and experiments show that the RCPWM is effective. Studies show that the harmonic spectrum is distributed more uniformly in the frequency domain and that there is no obvious peak in the wave spectra. The proposed method is of great value to research on RCPWM and integrated power systems (IPS).

Effects of rehydration on physiological and transcriptional responses of a water-stressed rhizobium

Zhu Jie,Jiang Xin,Guan Dawei,Kang Yaowei,Li Li,Cao Fengming,Zhao Baisuo,Ma Mingchao,Zhao Ji,Li Jun 한국미생물학회 2022 The journal of microbiology Vol.60 No.1

As a microsymbiont of soybean, Bradyrhizobium japonicum plays an important role in symbiotic nitrogen fixation and sustainable agriculture. However, the survival of B. japonicum cells under water-deplete (e.g., drought) and water-replete (e.g., flood) conditions is a major concern affecting their nitrogen-fixing ability by establishing the symbiotic relationship with the host. In this study, we isolated a water stress tolerant rhizobium from soybean root nodules and tested its survival under water-deplete conditions. The rhizobium was identified as Bradyrhizobium japonicum and named strain 5038. Interestingly, both plate counting and live/dead fluorescence staining assays indicate that a number of viable but non-culturable cells exist in the culture medium upon the rehydration process which could cause dilution stress. Bradyrhizobium japonicum 5038 cells increased production of exopolysaccharide (EPS) and trehalose when dehydrated, suggesting that protective responses were stimulated. As expected, cells reduced their production upon the subsequent rehydration. To examine differential gene expression of B. japonicum 5038 when exposed to water-deplete and subsequent waterreplete conditions, whole-genome transcriptional analysis was performed under 10% relative humidity (RH), and subsequent 100% RH, respectively. A total of 462 differentially expressed genes (DEGs, > 2.0-fold) were identified under the 10% RH condition, while 3,776 genes showed differential expression during the subsequent rehydration (100% RH) process. Genes involved in signal transduction, inorganic ion transport, energy production and metabolisms of carbohydrates, amino acids, and lipids were far more up-regulated than downregulated in the 10% RH condition. Notably, trehalose biosynthetic genes (otsAB, treS, and treYZ), genes ligD, oprB, and a sigma factor rpoH were significantly induced by 10% RH. Under the subsequent 100% RH condition, genes involved in transcription, translation, cell membrane regulation, replication and repair, and protein processing were highly up-regulated. Interestingly, most of 10%-RH inducible genes displayed rehydration-repressed, except three genes encoding heat shock (Hsp20) proteins. Therefore, this study provides molecular evidence for the switch of gene expression of B. japonicum cells when encountered the opposite water availability from water-deplete to water-replete conditions.

Efficacy and Safety of Bevacizumab in Chinese Patients with Metastatic Colorectal Cancer

Zhu, Li-Ming,Zhao, Ya-Zhen,Ju, Hai-Xing,Liu, Lu-Ying,Chen, Lei,Liu, Bi-Xia,Xu, Qi,Luo, Cong,Ying, Jie-Er,Yang, Yun-Shan,Zhong, Hai-Jun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Objective: To evaluate the efficacy and safety of bevacizumab in the treatment of patients with metastatic colorectal cancer (mCRC). Methods: In a single-center, observational study of 91 Chinese patients with mCRC who received bevacizumab in combination with chemotherapy was conducted. Objective response rates (ORRs), progression-free survival (PFS), overall survival (OS) and adverse events were recorded, and the relationships between various clinical factors and PFS or OS were evaluated by Cox proportional hazards models. Results: Treatment with bevacizumab and chemotherapy was effective and tolerable. Univariate analysis showed that PFS and OS were significantly associated with the Eastern Cooperative Oncology Group performance status (ECOG-PS) score, duration of bevacizumab exposure, and whether chemotherapy was continued after discontinuation of bevacizumab treatment. A multivariate analysis showed that the duration of bevacizumab exposure and whether chemotherapy was continued after discontinuation of bevacizumab were independent prognostic factors for PFS and OS. Conclusion: In Chinese mCRC population, the shorter the duration of exposure to bevacizumab and chemotherapy, the worse the prognosis is.

Study on the Magnetic Rate Sensitivity and Shear Properties of Magnetorheological Shear Thickening Fluid

Guo-Jun Yu,Shao-Jie Zhu,Cheng-Bin Du,Ling-Yun Wang,Jun-Chi Huang 한국자기학회 2023 Journal of Magnetics Vol.28 No.3

This paper studies magnetic field control and velocity-activated magnetorheological shear thickening fluid (MR-STF). High-concentration STF is composed of nano-sized silica particles suspended in a solvent polyethylene glycol (PEG), and then micron-sized carbonyl iron particles of different mass fractions are added to the STF to manufacture different MR-STF. The rheometer is used to study the viscoelasticity of all four samples. The correlation between dynamic behavior and shear rate, angular frequency, and external magnetic field is studied and discussed. In the lower angular frequency range, the loss modulus is slightly larger than the storage modulus, and MR-STF behaves as a viscoelastic state. After the critical angular frequency, the storage modulus decreases sharply, well below the loss modulus. MR-STF appears in a viscous state and a liquid state. With the start of external field excitation, MR-STF is more inclined to MRF. Finally, the apparent viscosity and shear rate of MR-STF are fitted. The results show that with the increase of magnetic induction strength, the plastic viscosity coefficient of MR fluid increases, the flow characteristic index decreases, and the shear thinning effect becomes more significant.

Pseudonocardia rhizophila sp. nov., a novel actinomycete isolated from a rhizosphere soil

Li, Jie,Zhao, Guo-Zhen,Huang, Hai-Yu,Zhu, Wen-Yong,Lee, Jae-Chan,Kim, Chang-Jin,Xu, Li-Hua,Zhang, Li-Xin,Li, Wen-Jun Springer-Verlag 2010 Antonie van Leeuwenhoek Vol.98 No.1

Epidemiological Patterns of Cancer Incidence in Southern China: Based on 6 Population-based Cancer Registries

Liu, Jie,Yang, Xu-Li,Li, Ai,Chen, Wan-Qing,Ji, Lu,Zhao, Jun,Yan, Wei,Chen, Yi-Ying,Zhu, Li-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Background: The epidemiological patterns of cancer incidence have been investigated widely in western countries. Nevertheless, information is quite limited in Jiangxi province, southern China. Materials and Methods: All data were reported by 6 population-based cancer registries in Jiangxi Province. The results were presented as incidence rates of cases by site (ICD-10), sex, crude rate (CR), age-standardized rates (ASRs) and truncated incidence rate (TR) per 100,000 person-years, using the direct method of standardization to the world population. Results: 8,765 new cancer cases were registered in our study during the period 2009-2011. Diagnosis of cancer was based on histopathology in 61.0%, clinical or radiology findings in 4.87% and death certificate only (DCO) in 3.0% of the cases. The median age at diagnosis was 62.0 years (mean, 61; standard deviation, 15). The ASRs were 170.8 per 100,000 for men and 111.2 for women. The ASRs for all invasive cancers from the urban areas (145.7 per 100,000) was higher than that of rural areas (137.1). Incidence rates for lung cancer were higher in rural (35.8) than in urban areas (27.0). Similarly, relatively high rates were observed for stomach cancer in rural (20.1) relative to urban areas (15.5). Conclusions: Our results reveal that the most common cancers were breast and lung in women and lung and liver in men. Interestingly, this study suggested a higher incidence rates for lung and stomach cancer in rural males than in urban population, which may suggest other potential causes, such as over-consumption of smoked meats and high prevalence of Helicobacter pylori infection, respectively. Public education and the promotion of healthy lifestyles should be actively carried out.

An improved SCGM(1,m) model for multi-point deformation analysis

Qi-jie Wang,Chang-cheng Wang,Rong-an Xie,Xin-qing Zhang,Jian-jun Zhu 한국지질과학협의회 2014 Geosciences Journal Vol.18 No.4

Considering the deformation of discrete monitoringpoints within the same deformable body usually have similar physicalproperties and tend to undergoing identical dynamic process, jointmodelling of the deformation processes of these points in time domainare expected to generate better results. Yin et al. (1997) first extendedthe multi-variable grey model-system cloud grey model SCGM(1,m),with obviously superior modelling mechanism than single-variablegrey model, to multi-point deformation modelling. However, thismodel is still not widely recognized and its applications remain verylimited in the field of deformation analysis. The objective of this studyis to demonstrate the capability of the SCGM(1,m) model, to presenttwo revisions to further improve the performance of the model andto draw more attention to the community of deformation analysis. We first introduce the principles of the SCGM(1,m) model in theanalysis and prediction of deformation surveys. Two practicaltechniques, namely residuals re-modelling and linear regressionadjustment, are then presented to improve the SCGM(1,m) model. Combined with slope monitoring data, the modelling with the originaland the improved SCGM(1,m) models by residuals re-modellingand linear regression adjustment are illustrated. The mean relativeprediction errors decrease from 5.89% to 3.54% and 2.69%, whenthe two refining techniques are applied, respectively, indicating relativeimprovements of 39.9% and 54.3%.

Etoposide-Cisplatin Alternating with Vinorelbine-Cisplatin Versus Etoposide-Cisplatin Alone in Patients with Extensive Disease Combined with Small Cell Lung Cancer

Zhang, Jie,Qi, Hui-Wei,Zheng, Hui,Chen, Mo,Zhu, Jun,Xie, Hui-Kang,Ni, Jian,Xu, Jian-Fang,Zhou, Cai-Cun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

Background: The aim of this study was to evaluate the efficacy of alternating etoposide-cisplatin and vinorelbine-cisplatin (EP-NP) compared with an etoposide-cisplatin (EP) regimen for advanced combined small cell carcinomas. Materials and Methods: Histologically confirmed combined small cell carcinoma patients who met the inclusion criteria were randomly assigned (1:1) into either the EP-NP setting (group A) or the EP setting (group B). The primary endpoint was progression-free survival in patients who received at least one dose of treatment. Results: Eighty-two patients entered into this trial, 42 in group A and 40 in group B. The objective response rates in group A and group B were 42.9% and 32.5%, respectively (p=0.334). Survival analysis showed that median progression-free survival was 6.1 months in group A, which was significantly longer than the 4.1 months in group B (p=0.041). However, as to overall survival, no significant difference was found between the two groups (11.0 vs 10.1 months in groups A and B, respectively, p=0.545). No unexpected side effects were observed in either group. Conclusions: The EP-NP regimen for combined small cell carcinomas prolonged progressio-nfree survival compared with the EP regimen. Further clinical investigations are warranted.