Design of Micro Biopsy Device for Wireless Autonomous Endoscope

Wen-Wen Chen,Guo-Zheng Yan,Hua Liu,Ping-Ping Jiang,Zhi-Wu Wang 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Well-established technology that provides assistance from outside the patient may soon give way to alternative approaches that bythe wireless robotic mechanisms inside the patient through natural orifices. For this study, two kinds of micro biopsy mechanisms weredeveloped for capsule endoscope which could traverse the gut environment automatically. This mobility allows the biopsy device tomove to the area of interest to sample specific tissues. Based on the medical and mechanism considerations, we concerned on designprecise biopsy jaw with sufficient cutting force, and the biopsy process should be safe, repeatable and visible. The lead-screw linkagesystem that actuated jaw of biopsy allowing for large force production. Using one micro-motor, the biopsy process was carried outquickly by three motions: stretching to sampling point; bite and cutting off; withdrawing into capsule body with the sample. With thecontrol and vision system, the biopsy process could compete automatically. The robot was capable of traversing in the gut environmentwirelessly and had been successfully used to biopsy gut tissue in vitro. In addition, experimental analysis of the biopsy mechanismshowed good results towards more elaborate tissue manipulation in the future.

An Improved Active Damping Method with Capacitor Current Feedback

Yi-Wen Geng,Ya-Wen Qi,Hai-Wei Liu,Fei Guo,Peng-Fei Zheng,Yong-Gang Li,Wen-Ming Dong 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Proportional capacitor current feedback active damping (CCFAD) has a limited valid damping region in the discrete time domain as (0, fs/6). However, the resonance frequency (fr) of an LCL-type filter is usually designed to be less than half the sampling frequency (fs) with the symmetry regular sampling method. Therefore, (fs/6, fs/2) becomes an invalid damping region. This paper proposes an improved CCFAD method to extend the valid damping region from (0, fs/6) to (0, fs/2), which covers all of the possible resonance frequencies in the design procedure. The full-valid damping region is obtained and the stability margin of the system is analyzed in the discrete time domain with the Nyquist criterion. Results show that the system can operate stably with the proposed CCFAD method when the resonance frequency is in the region (0, fs/2). The performances at the steady and dynamic state are enhanced by the selected feedback coefficient H and controller gain Kp. Finally, the feasibility and effectiveness of the proposed CCFAD method are verified by simulation and experimental results.

An Improved Active Damping Method with Capacitor Current Feedback

Geng, Yi-Wen,Qi, Ya-Wen,Liu, Hai-Wei,Guo, Fei,Zheng, Peng-Fei,Li, Yong-Gang,Dong, Wen-Ming The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Proportional capacitor current feedback active damping (CCFAD) has a limited valid damping region in the discrete time domain as (0, $f_s/6$. However, the resonance frequency ($f_r$) of an LCL-type filter is usually designed to be less than half the sampling frequency ($f_s$) with the symmetry regular sampling method. Therefore, ($f_s/6$, $f_s/2$) becomes an invalid damping region. This paper proposes an improved CCFAD method to extend the valid damping region from (0, $f_s/6$ to (0, $f_s/2$), which covers all of the possible resonance frequencies in the design procedure. The full-valid damping region is obtained and the stability margin of the system is analyzed in the discrete time domain with the Nyquist criterion. Results show that the system can operate stably with the proposed CCFAD method when the resonance frequency is in the region (0, $f_s/2$). The performances at the steady and dynamic state are enhanced by the selected feedback coefficient H and controller gain $K_p$. Finally, the feasibility and effectiveness of the proposed CCFAD method are verified by simulation and experimental results.

Capacity design of boundary elements of beam-connected buckling restrained steel plate shear wall

Wen-Yang Liu,Guo-Qiang Li,Jian Jiang 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.29 No.2

As a lateral load resisting component, buckling restrained steel plate shear walls (BRW) have excellent energy dissipating capacity. Similar to thin steel plate shear walls, the mechanical behavior of BRWs depends on the boundary elements (adjacent beams and columns) which need adequate strength and stiffness to ensure the complete yielding of BRWs and the emergence of expected plastic collapse mechanism of frame. This paper presents a theoretical approach to estimate the design forces for boundary elements of beam-connected BRW (i.e., The BRW is only connected to beams at its top and bottom, without connections to columns) using a fundamental plastic collapse mechanism of frame, a force transferring model of beamconnected BRW and linear beam and column analysis. Furthermore, the design method of boundary beams and columns is presented. The proposed approach does not involve nonlinear analyses, which can be easily and efficiently used to estimate the design forces of beams and columns in a frame with BRWs. The predicted design forces of boundary elements are compared with those from nonlinear finite element analyses, and a good agreement is achieved.

An Empirical Analysis of Sino-Russia Foreign Trade Turnover Time Series: Based on EMD-LSTM Model

GUO, Jian,WU, Kai Kun,YE, Lyu,CHENG, Shi Chao,LIU, Wen Jing,YANG, Jing Ying Korea Distribution Science Association 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.10

The time series of foreign trade turnover is complex and variable and contains linear and nonlinear information. This paper proposes preprocessing the dataset by the EMD algorithm and combining the linear prediction advantage of the SARIMA model with the nonlinear prediction advantage of the EMD-LSTM model to construct the SARIMA-EMD-LSTM hybrid model by the weight assignment method. The forecast performance of the single models is compared with that of the hybrid models by using MAPE and RMSE metrics. Furthermore, it is confirmed that the weight assignment approach can benefit from the hybrid models. The results show that the SARIMA model can capture the fluctuation pattern of the time series, but it cannot effectively predict the sudden drop in foreign trade turnover caused by special reasons and has the lowest accuracy in long-term forecasting. The EMD-LSTM model successfully resolves the hysteresis phenomenon and has the highest forecast accuracy of all models, with a MAPE of 7.4304%. Therefore, it can be effectively used to forecast the Sino-Russia foreign trade turnover time series post-epidemic. Hybrid models cannot take advantage of SARIMA linear and LSTM nonlinear forecasting, so weight assignment is not the best method to construct hybrid models.

Associations Between RASSF1A Promoter Methylation and NSCLC: A Meta-analysis of Published Data

Liu, Wen-Jian,Tan, Xiao-Hong,Guo, Bao-Ping,Ke, Qing,Sun, Jie,Cen, Hong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Background: RASSF1A has been reported to be a candidate tumor suppressor in non-small cell lung cancer (NSCLC). However, the association between RASSF1A promoter methylation and NSCLC remains unclear, particularly in regarding links to clinicopathologic features. Methods: Eligible studies were identified through searching PubMed, EMBASE, Cochrane Library and China National Knowledge Infrastructure (CNKI) databases. Studies were pooled and odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated. Funnel plots were also performed to evaluate publication bias. Results: Nineteen studies involving 2,063 cases of NSCLC and 1,184 controls were included in this meta-analysis. A significant association was observed between RASSF1A methylation and NSCLC in the complete data set (OR = 19.42, 95% CI: 14.04-26.85, P < 0.001). Pooling the control tissue subgroups (heterogeneous/autologous) gave pooled ORs of 32.4 (95% CI, 12.4-84.5) and 17.7 (95% CI, 12.5-25.0) respectively. Racial subgroup (Caucasian/Asian) analysis gave pooled ORs of 26.6 (95% CI, 10.9-64.9) and 20.9 (95% CI, 14.4-30.4) respectively. The OR for RASSF1A methylation in poorly-differentiated vs. moderately/well-differentiated NSCLC tissues was 1.88 (95% CI, 1.32-2.68, P<0.001), whereas there were no significant differences in RASSF1A methylation in relation to gender, pathology, TNM stage and smoking behavior among NSCLC cases. Conclusion: This meta-analysis suggests a significant association between RASSF1A methylation and NSCLC, confirming the role of RASSF1A as a tumor suppressor gene. Large-scale and well-designed case-control studies are needed to validate the associations identified in the present meta-analysis.

Drug Resistance Effects of Ribosomal Protein L24 Overexpression in Hepatocellular Carcinoma HepG2 Cells

Guo, Yong-Li,Kong, Qing-Sheng,Liu, Hong-Sheng,Tan, Wen-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.22

Background: The morbidity and mortality rate of liver cancer continues to rise in China and advanced cases respond poorly to chemotherapy. Ribosomal protein L24 has been reported to be a potential therapeutic target whose depletion or acetylation inhibits polysome assembly and cell growth of cancer. Materials and Methods: Total RNA of cultured amycin-resistant and susceptible HepG2 cells was isolated, and real time quantitative RT-PCR were used to indicate differences between amycin-resistant and susceptible strains of HepG2 cells. Viability assays were used to determine amycin resistance in RPL24 transfected and control vector and null-transfected HepG2 cell lines. Results: The ribosomal protein L24 transcription level was 7.7 times higher in the drug-resistant HepG2 cells as compared to susceptible cells on quantitative RT-PCR analysis. This was associated with enhanced drug resistance as determined by methyl tritiated thymidine (3H-TdR) incorporation. Conclusions: The ribosomal protein L24 gene may have effects on drug resistance mechanisms in hepatocellular carcinoma HepG2 cells.

Actinorugispora endophytica gen. nov., sp. nov., an actinomycete isolated from Daucus carota.

Liu, Min-Jiao,Zhu, Wen-Yong,Li, Jie,Zhao, Guo-Zhen,Xiong, Zhi,Park, Dong-Jin,Hozzein, Wael N,Kim, Chang-Jin,Li, Wen-Jun Society for General Microbiology 2015 International journal of systematic and evolutiona Vol.65 No.8

<P>An actinomycete strain, designated YIM 690008T, was isolated from Daucus carota collected from South Korea and its taxonomic position was investigated by using a polyphasic approach. The strain grew well on most media tested and no diffusible pigment was produced. The aerial mycelium formed wrinkled single spores and short spore chains, some of which were branched. The whole-cell hydrolysates contained meso-diaminopimelic acid, glucose, mannose, ribose, galactose and rhamnose. The predominant menaquinones were MK-10(H4), MK-10(H6), MK-10(H8) and MK-10(H2). The polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannosides, some unknown phospholipids, glycolipids and polar lipids. The major fatty acids were i-C16?:?0, ai-C17?:?0 and C18?:?1ω9c. The DNA G+C content of the genomic DNA was 63.1?mol%. Phylogenetic analysis indicated that the isolate belongs to the family Nocardiopsaceae. However, based on phenotypic, chemotaxonomic and genotypic data, it was concluded that strain YIM 690008T represents a novel genus and novel species of the family Nocardiopsaceae, for which the name Actinorugispora endophytica gen. nov., sp. nov. (type strain YIM 690008T?=?DSM 46770T?=?JCM 30099T?=?KCTC 29480T) is proposed.</P>

Impact performance for high frequency hydraulic rock drill drifter with sleeve valve

Guo, Yong,Yang, Shu Yi,Liu, De Shun,Zhang, Long Yan,Chen, Jian Wen Korean Society for Fluid machinery 2016 International journal of fluid machinery and syste Vol.9 No.1

A high frequency hydraulic rock drill drifter with sleeve valve is developed to use on arm of excavator. In order to ensure optimal working parameters of impact system for the new hydraulic rock drill drifter controlled by sleeve valve, the performance test system is built using the arm and the hydraulic source of excavator. The evaluation indexes are gained through measurement of working pressure, supply oil flow and stress wave. The relations of working parameters to impact system performance are analyzed. The result demonstrates that the maximum impact energy of the drill drifter is 98.34J with impact frequency of 71HZ. Optimal pressure of YZ45 rock drill is 12.8 MPa-13.6MPa, in which the energy efficiency reaches above 58.6%, and feature moment of energy distribution is more than 0.650.

The Data Processing Method for Small Samples and Multi-variates Series in GPS Deformation Monitoring

Liu Guo-lin,Zheng Wen-Hua,Wang Xin-zhou,Zhang Lian-Peng 한국항해항만학회 2006 한국항해항만학회 학술대회논문집 Vol.1 No.-

Time series analysis is a frequently effective method of constructing model and prediction in data processing of deformation monitoring. The monitoring data sample must to be as more as possible and time intervals are equal roughly so as to construct time series model accurately and achieve reliable prediction. But in the project practice of GPS deformation monitoring, the monitoring data sample can’t be obtained too much and time intervals are not equal because of being restricted by all kinds of factors, and it contains many variates in the deformation model moreover. It is very important to study the data processing method for small samples and multi-variates time series in GPS deformation monitoring. A new method of establishing small samples and multi-variates deformation model and prediction model are put forward so as to resolve contradiction of small samples and multi-variates encountered in constructing deformation model and improve formerly data processing method of deformation monitoring. Based on the system theory, a deformation body is regarded as a whole organism; a time-dependence linear system model and a time-dependence bilinear system model are established. The dynamic parameters estimation is derived by means of prediction fit and least information distribution criteria. The final example demonstrates the validity and practice of this method.