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      • KCI등재

        Nonlinear Hybrid Controller Design for Perturbed Quadrotor Robot by Uncertainties

        Ju-Qian Zhang,Yu-Ru Shi,Yong Wu,Bang-chun Wen 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.11

        In this paper, a novel nonlinear hybrid observers (HOB) based dynamic surface control (DSC) system, which integrates nominal and compensation controller, is designed for autonomous quadrotor robot perturbed by the uncertainties, e.g., external disturbances and measurement-delay. In this hybrid control system, the nominal controller based on dynamic surface control superior to the backstepping technique is the main controller, and the disturbance observer (DOB) is incorporated as the compensation controller to eliminate the effect of uncertainties caused by model mismatch and external disturbances. In addition, in order to relax the impact of measurement-delay induced by sensors of poor quality and heavy computation burden, the measurement-delay observer (MOB) is derived. Next, stability of the closed-loop control system is analytically proved based on Lyapunov theorem. Finally, comparative controllers are evaluated on simulation and experimental environments to demonstrate the effectiveness and merits of the proposed controller for quadrotor robot against the uncertainties.

      • KCI등재

        A simple unstructured model-based control for efficient expression of recombinant porcine insulin precursor by Pichia pastoris

        Siliang Zhang,Hai-feng Hang,Wen Chen,Mei-jin Guo,Ju Chu,Ying-ping Zhuang 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.5

        Based on the fact that Pichia cell growth follows a Monod equation under the condition of methanol concentration limitation, a kinetics model of recombinant methylotrophic yeast Pichia pastoris expressing porcine insulin precursor (PIP) was developed in the quasi-steady state in the induction phase. The model revealed that the relationship between specific growth rate (μ) and substrate methanol concentration was in accord with the Monod equation. The fermentation kinetic parameters maximum specific growth rate (μmax), saturation constant (Ks) and maintenance coefficient (M) were estimated to be 0.101 h−1, 0.252 g l−1, and 0.011 g MeOH g−1 DCW h−1, respectively. The unstructured model was validated in methanol induction phase with different initial cell densities. Results showed that the maximum specific protein production rate (qp.max) of 0.098 mg g−1 DCW h−1 was achieved when μ was kept at 0.016 h−1, and the maximum yield of PIP reached 0.97 g l−1, which was 1.5-fold as that of the control. Therefore, the simple Monod model proposed has proven to be a robust control system for recombinant porcine insulin precursor production by P. pastoris on pilot scale, which would be further applied on production scale.

      • KCI등재

        Epsilon-Fe₂O₃ is a novel intermediate for magnetite biosynthesis in magnetotactic bacteria

        Tong Wen,Yunpeng Zhang,Yuanyuan Geng,Junquan Liu,Abdul Basit,Jiesheng Tian,Ying Li,Ji-Lun Li,Jing Ju,Wei Jiang 한국생체재료학회 2019 생체재료학회지 Vol.23 No.3

        Background: Natural biological magnetite nanoparticles are widely distributed from microorganisms to humans. It is found to be very important in organisms, especially in navigation. Moreover, purified magnetite nanoparticles also have potential applications in bioengineering and biomedicine. Magnetotactic bacteria (MTB) is considered one of the most abundant species around the world which can form intracellular membrane enveloped magnetic nanoparticles, referred to as magnetosomes. To our knowledge, the biomineralization of magnetosome in MTB involves a serious of genes located on a large unstable genomic region named magnetosome island, which specially exists in MTB. The magnetite core of magnetosome formed via a Fe (III) ion intermediates, for instance, α-Fe2O3 and ferrihydrite. Though the biosynthesis of magnetosome represents a general biomineralization mechanism of biogenic magnetite, knowledge of magnetosome biosynthesis and biomineralization remains very limited. Method: Cells used in this study were cultured in a 7.5-L bioreactor, samples for intermediate capture were taken each certain time interval after the generation of magnetosome biosynthesis condition. High-resolution transmission electron microscopy were used to analyze the detailed structure of magnetosomes. The parameters of the crystal structures were obtained by Fast Fourier Transform analyses. Results: In this study, we identified a novel intermediate phase, ε-Fe2O3, during the magnetite maturation process in MTB via kinetic analysis. Unlike α-Fe2O3, which has been reported as a precursor during magnetosome biosynthesis in MTB before, ε-Fe2O3, due to its thermal instability, is a rare phase with scarce natural abundance. This finding confirmed that ε-Fe2O3 is an important novel intermediate during the biomineralization of magnetosome in MTB, and shed new light on the magnetosome biosynthesis pathway.

      • Evaluation of Several Screening Approaches for Detection of Cervical Lesions in Rural Shandong, China

        Zong, Li-Ju,Zhang, You-Zhong,Yang, Xing-sheng,Jiang, Jie,Cui, Bao-Xia,Qiao, Yun-Bo,Li, Li,Jiang, Kan,Zhang, Wen-Jing,Kong, Bei-Hua,Shen, Keng Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

        Purpose: The study was designed to: (1) investigate the prevalence of high-risk human papillomavirus (HR-HPV) infection and cervical neoplasia; and (2) evaluate clinical performance of visual inspection with acetic acid/ Lugol's iodine (VIA /VILI), Pap smear, high-risk human papillomavirus (HR-HPV) DNA test for detecting cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and (3) explore appropriate screening approach in rural areas of Shandong Province. Materials and Methods: A total of 3,763 eligible women from Yiyuan County in Yimeng mountainous areas of rural Shandong, China, were enrolled and underwent Pap smear, HR-HPV DNA testing by Hybrid Capture 2 (HC2), and VIA /VILI tests. Women positive in any test were referred to colposcopy and biopsy as indicated. Results: The prevalence of HR-HPV infection among all enrolled women was 11.1% and that in healthy women was 9.9%. In total 33 cases of CIN1, 16 cases of CIN2, 6 cases of CIN3 but none of cervical cancer were detected and the crude prevalence of CIN2+ was 0.58%. For detecting CIN2+, the sensitivity of HR-HPV DNA testing, VIA/VILI, Pap smear was 90.9%, 77.3%, 81.8%, respectively. Pap smear had the best specificity of 98.2%, followed by HR-HPV DNA testing with specificity of 89.4%, VIA/VILI had the lowest specificity of 81.2%. Colposcopy referral rate of HR-HPV DNA testing, VIA/VILI, Pap smear was 11.1%, 18.5%, 2.3%, respectively. Conclusions: Our results suggest that HR-HPV DNA testing alone might be appropriate for primary cervical cancer screening in rural low-resource areas of Shandong Province, China.

      • KCI등재

        Antiviral effects of Bovine antimicrobial peptide against TGEV in vivo and in vitro

        Xiuli Liang,Xiaojun Zhang,Kaiqi Lian,Xiuhua Tian,Mingliang Zhang,Shiqiong Wang,Cheng Chen,Cunxi Nie,Yun Pan,Fangfang Han,Zhanyong Wei,Wen-Ju Zhang 대한수의학회 2020 Journal of Veterinary Science Vol.21 No.5

        Background: In suckling piglets, transmissible gastroenteritis virus (TGEV) causes lethal diarrhea accompanied by high infection and mortality rates, leading to considerable economic losses. This study explored methods of preventing or inhibiting their production. Bovine antimicrobial peptide-13 (APB-13) has antibacterial, antiviral, and immune functions. Objectives: This study analyzed the efficacy of APB-13 against TGEV through in vivo and in vitro experiments. Methods: The effects of APB-13 toxicity and virus inhibition rate on swine testicular (ST) cells were detected using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT). The impact of APB-13 on virus replication was examined through the 50% tissue culture infective dose (TCID50). The mRNA and protein levels were investigated by real-time quantitative polymerase chain reaction and western blot (WB). Tissue sections were used to detect intestinal morphological development. Results: The safe and effective concentration range of APB-13 on ST cells ranged from 0 to 62.5 μg/mL, and the highest viral inhibitory rate of APB-13 was 74.1%. The log10TCID50 of 62.5 μg/mL APB-13 was 3.63 lower than that of the virus control. The mRNA and protein expression at 62.5 μg/mL APB-13 was significantly lower than that of the virus control at 24 hpi. Piglets in the APB-13 group showed significantly lower viral shedding than that in the virus control group, and the pathological tissue sections of the jejunum morphology revealed significant differences between the groups. Conclusions: APB-13 exhibited good antiviral effects on TGEV in vivo and in vitro.

      • SCIESCOPUSKCI등재

        Model to Predict Absorbed Amino Acid Supply at the Proximal Duodenum in Growing Beef Cattle

        Yan, Xianghua,Xu, Zirong,Zhang, Wen-ju,Wang, Jiaqi Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.3

        Five crossbred beef cattle (Simmental${\times}$yellow cattle, Shantung Province) fitted with permanent cannulae in the rumen and T-type cannulae at the proximal duodenum and terminal ileum, were fed five different diets containing corn, cotton meal or soybean meal and ammoniated straw to determine the dry matter, crude protein and amino acid flows in duodenal and ileum digesta, and to calculate the regression equations between theoretical and experimental concentration of AA in duodenal digesta. The results showed that there was a strong correlation between experimental (g/d, y) and theoretical CP flows (g/d, x) at the proximal duodenum, the $R^2$-value regression equation of crude protein is very high (0.9636). The $R^2$-value regression equation of the limiting amino acid (such as Met or Lys) is high (0.7573 or 0.9252 respectively). This results indicated that we can formulate better diets fed to beef cattle according to the theoretical amino acid concentration. A mathematical model has been successfully constructed for predicting the supply of absorbed amino acids at the proximal duodenum in growing beef cattle.

      • KCI등재

        Nonlinear dynamics analysis of multi-cutting wire electrode in WEDM-HS subjected to working fluid considering the effect of debris

        Sheng-Yao Fan,Qiu-Ju Zhang,Hai-Wei Chen,Wen-xuan Zeng 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.12

        A reasonable dielectric fluid velocity and better exclusion of debris are very important to obtain a stable machining performance in multi-cutting of WEDM-HS. We investigated the dynamic characteristics of multi-cutting wire electrode in WEDM-HS subjected to working fluid considering the effect of debris. First, a fluid-solid coupling nonlinear vibration model is derived by analyzing the forces acting on the multi-cutting wire which locate in the dielectric fluid. The additional axial force arising from the transverse vibration of the multi-cutting wire is considered as a nonlinear term in the model. Considering that the debris accumulation in discharge gap severely influences the stability of multi-cutting wire electrode, the relationship between the debris volume concentration and debris-working fluid two-phase flow drag coefficient is obtained using the Einstein two-phase flow viscosity theory. Finally, the influences of several parameters on the multi-cutting wire displacement are discussed in detail.

      • SCIESCOPUSKCI등재

        Analysis of the Relationship between MHC-DRB1 Gene Polymorphism and Hydatidosis in Kazakh Sheep

        Li, Ren-Yan,Jia, Bin,Zhang, Wen-Ju,Zhao, Zong-Sheng,Shi, Guo-Qing,Shen, Hong,Peng, Qiang,Lv, Li-Min,Zhou, Qi-Wei,Du, Ying-Chun Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.9

        The objective of this work was to analyze the relationship between ovine major histocompatibility complex (MHC) DRB1 gene polymorphism and genetic resistance to hydatidosis in Kazakh sheep. The Ovar (ovine MHC) class II DRB1 second exon was amplified by polymerase chain reaction (PCR) from DNA samples of 702 Kazakh sheep, including 302 sheep with hydatidosis and 400 health controls. PCR products were characterized by the restriction fragment length polymorphism (RFLP) technique using five restriction enzymes, i.e., MvaI, HaeIII, SacI, SacII and Hin1I, yielding 14 alleles and 28 genotypes. Comparing the frequency of genotypes in hydatidosis sheep with the control group, it was found that the genotype frequencies of MvaIbc, Hin1Iab, SacIIab, HaeIIIde, HaeIIIdf and HaeIIIdd in control sheep were significantly (p<0.01) higher than in hydatidosis sheep, indicating that a significant correlation existed between these genotypes and resistance to hydatidosis. Genotype frequencies of MvaIbb, SacIIaa, Hin1Ibb and HaeIIIef in sheep with hydatidosis were extremely significantly (p<0.01) higher than in the control group, and the genotype frequency of HaeIIIab was significantly higher (p<0.05), indicating that a marked correlation existed between these genotypes and susceptibility to hydatidosis. By way of analyzing haplotype with these resistant genotypes, the hydatidosis resistant haplotype MvaIbc-SacIIab-Hin1Iab of Kazakh sheep was screened out, and then verified through artificial hydatid infection in sheep. The results indicated that the infection rate of sheep with the resistant haplotype of hydatidosis was significantly lower (p<0.01) than without this resistant haplotype. It showed that the genic haplotype MvaIbc-SacIIab-Hin1Iab of Ovar-DRB1 exon 2 was the resistant haplotype of hydatidosis in Kazakh sheep.

      • SCIEKCI등재

        Prognostic value of hyponatremia in heart failure patients: an analysis of the Clinical Characteristics and Outcomes in the Relation with Serum Sodium Level in Asian Patients Hospitalized for Heart Failure (COAST) study

        ( Byung Su Yoo ),( Jin Joo Park ),( Dong Ju Choi ),( Seok Min Kang ),( Juey Jen Hwang ),( Shing Jong Lin ),( Ming Shien Wen ),( Jian Zhang ),( Junbo Ge ) 대한내과학회 2015 The Korean Journal of Internal Medicine Vol.30 No.4

        Background/Aims: Hyponatremia is a well-known risk factor for poor outcomes in Western studies of heart failure (HF) patients. We evaluated the predictive value of hyponatremia in hospitalized Asian HF patients. Methods: The Clinical Characteristics and Outcomes in the Relation with Serum Sodium Level in Asian Patients Hospitalized for Heart Failure (the COAST) study enrolled hospitalized patients with systolic HF (ejection fraction < 45%) at eight centers in South Korea, Taiwan, and China. The relationship between admissionsodium level and clinical outcomes was analyzed in 1,470 patients. Results: The mean admission sodium level was 138 ± 4.7 mmol/L, and 247 patients (16.8%) had hyponatremia defined as Na+ < 135 mmol/L. The 12-month mortality was higher in hyponatremic patients (27.9% vs. 14.6%, p < 0.001), and hyponatremia was an independent predictor of 12-month mortality (hazard ratio, 1.72; 95% confidence interval, 1.12 to 2.65). During hospital admission, 57% of hyponatremic patients showed improvement without improvement in their clinical outcomes (p = 0.620). The proportion of patients with optimal medical treatment was only 26.5% and 44.2% at admission and discharge, respectively, defined as thecombined use of angiotensin-converting-enzyme inhibitor/angiotensin receptor blocker and β-blocker. Underuse of optimal medical treatment was more pronounced in hyponatremic patients. Conclusions: In hospitalized Asian HF patients, hyponatremia at admission is common and is an independent predictor of poor clinical outcome. Furthermore, hyponatremic patients receive less optimal medical treatment than their counterparts.

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