Dynamic characteristics and test analysis of a new drilling downhole tool with anti-stick-slip features

Jia-lin Tian,Tangjia Zhang,Liming Dai,Wenming Cheng,Lin Yang,Chang-fu Yuan 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

A key problem in drill string dynamics is the stick–slip in deep and large displacement horizontal wells that may lead to the decline in drilling performance or cause tool failure, which may eventually cause underground accidents. Therefore, the research on the production safety, ROP, and increased efficiency in relation to stick–slip theory and practical stick–slip reduction is highly relevant, especially in complex drilling conditions. On this basis, this study takes the new constant torque tool as the engineering background and establishes the working mechanism analytical model of stick–slip reduction and torque constant. A helical dynamic model is established to solve the core problem of the constant torque tool. Then, the differential equation of the helical spline drive motion is deduced. The motion of the helical spline mandrel is calculated, and its analytical results are compared with simulation results. Findings show that the laws of angular displacement, angular velocity, axial displacement, and axial velocity are consistent with the simulation results when the helical spline mandrel moves up or down. The established theoretical model can promote the development of drill string dynamics in new drilling conditions. Moreover, the proposed designing methods can provide new ideas for the development of a stick–slip reduction tool. The results can be further used as reference for key parameter determination and stick–slip reduction technology optimization.

An Enhanced Reversible Data Hiding Scheme based on Histogram Modification

Lin Jia(지아린),Gil-Je Lee(이길제),Kee-Young Yoo(유기영) 대한전자공학회 2010 대한전자공학회 학술대회 Vol.2010 No.6

In 2008, Lin et al. proposed the multilevel reversible data hiding scheme based on the histogram modification but many distortions are created due to the histogram shifting method which is used in the embedding phase. In this paper, the proposed scheme combines the peak point bin with the adjacent bin of the histogram to decrease the above distortions. The expermential results show that the proposed scheme achieves the better performance than Lin et al.’s scheme in both the stego image quality and the hiding capacity.

Three Dimensional Nylon Cushioning Composite Fabrics: Manufacturing Technique and Property Evaluations

Jia-Ci Jhang,Ting Ru Lin,Yu-Chun Chuang,Ching-Wen Lou,Jia-Horng Lin 한국섬유공학회 2020 Fibers and polymers Vol.21 No.3

It is trendy to use polymers with different forms in a diversity of fields. This study uses nylon fibers and lowmelting-point polyester (LMPET) fibers or low melting point polylactic acid (LMPLA) fibers to fabricate three-dimensionalnylon/LMPET and nylon/LMPLA cushioning composite fabrics employing the nonwoven manufacturing. The employmentof needle punching process and thermal treatment reinforce the cushioning composite fabrics, and the subsequent thermalbonding points strengthen the mechanical properties effectively. In comparison to pure nylon nonwoven fabrics, the nyloncushioning composite fabrics exhibit higher tensile strength by 2.3 times regardless of whether it is a nylon/LMPET or nylon/LMPLA cushioning composite fabric. Similarly, based on the hammer rebound rate measurement, when the 3D cushioningcomposite fabrics are composed of 20 wt% of LMPLA fibers or 80 wt% of LMPET fibers, the hammer rebound rate reaches20 %, which is 1.4 times greater than that of the control group. Additionally, the composite fabrics that are composed of80 wt% of LMPLA fibers or 40 wt% of LMPET fibers also demonstrate higher compression recovery than the control group.

Experimental study on component performance in steel plate shear wall with self-centering braces

Jia-Lin Liu,Long-He Xu,Zhong-Xian Li 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.37 No.3

Steel plate shear wall with self-centering energy dissipation braces (SPSW-SCEDB) is a lateral force-resisting system that exhibits flag-shaped hysteretic responses, which consists of two pre-pressed spring self-centering energy dissipation (PS-SCED) braces and a wall plate connected to horizontal boundary elements only. The present study conducted a series of cyclic tests to study the hysteretic performances of braces in SPSW-SCEDB and the effects of braces on the overall hysteretic characteristics of this system. The SPSW-SCEDB with PS-SCED braces only exhibits excellent self-centering capability and the energy loss caused by the large inclination angle of PS-SCED braces can be compensated by appropriately increasing the friction force. Under the combined effect of the two components, the SPSW-SCEDB exhibits a flag-shaped hysteretic response with large lateral resistance, good energy dissipation and self-centering capabilities. In addition, the wall plate is the primary energy dissipation component and the PS-SCED braces provide supplementary energy dissipation for system. The PS-SCED braces can provide up to 90% self-centering capability for the SPSW-SCEDB system. The compressive bearing capacity of the wall plate should be smaller than the horizontal remaining restoring force of the braces to achieve better self-centering effect of the system.

The multidirectional vibration and coupling dynamics of drill string and its influence on the wellbore trajectory

Lin Yang,Jia-lin Tian,Qingyou Liu,Liming Dai,Zhichao Hu,Jurui Li 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.7

For improving the accuracy of wellbore trajectory prediction in complex wellbore structures, especially in the kick-off section, a longitudinal, torsional and radial coupled drill string dynamics model is proposed. At the same time, the coupling dynamics model is solved based on the energy method, and the torque, weight on bit (WOB), the longitudinal displacement and velocity, the torsional angular displacement and angular velocity of the drill bit are obtained during the normal drilling and the stick-slip vibration phase. Combining the numerical example and experimental test, the differences between different models and actual drilling trajectories are compared and analyzed. The research results indicate that the torsional vibration and the longitudinal vibration have a great influence on each other in the coupling model, and the longitudinal vibration displacement increases, which can effectively reduce the torque variation range of the torsional vibration. The operation of the bit stagnation is weakened, maintaining a relatively stable rotational angular velocity of rotation. The calculation results of the wellbore trajectory are more consistent with the experimental results, and can accurately reflect the real situation of the drilling process. The theoretical model has an important reference for predicting the new well structure, especially the judgment of wellbore trajectory of complex wellbore structures such as extended reach wells, horizontal wells, deep wells and high deep wells of coalbed methane, and the prediction of downhole dynamics results.

Courage Store II

( Lin Rui-lin ),( He Xin-hua ),( Chen Guan-ting ),( Chen Jia-ling ),( Jua Wei-ting ),( Lin Yen-chun ),( Yuan Zheng-xing ),( Lin Yi-ru ) 한국기초조형학회 2018 한국기초조형학회 작품집 Vol.2018 No.2

Research and experimental analysis of drill string dynamics characteristics and stick-slip reduction mechanism

Jia-lin Tian,Lai Wei,Lin Yang,Liming Dai,Tangjia Zhang,He Liu 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.3

Stick-slip of the drill string, as one of the critical factors affecting drilling efficiency, has always been a hot topic for experts and scholars in related fields. Serious stickslip vibration affects the well construction efficiency, drilling cost and even lead to a downhole accident. Therefore, based on the current research, this paper takes a new type of composite vibration tool as the research object, studies the working mechanism of the tool and analyzes the effect of stick-slip reduction. After establishing the multi-degree-of-freedom torsional dynamics model, we obtained the results of torsional vibration dynamics by cases analysis based on working conditions and related mechanical parameters. In addition, the results of the examples, compared with the field experimental data, verify that the vibration shock generated by the new composite tool can effectively reduce the torque fluctuation range of the system, avoid the occurrence of stick-slip phenomenon, improve the ROP (rate of penetration), and make drilling process more stable. This paper can provide reference for the optimization and development of stick-slip technology in drilling engineering, and the theoretical methods can also be developed to study the dynamics of drill string.

Lentivirus-mediated microRNA-124 gene-modified bone marrow mesenchymal stem cell transplantation promotes the repair of spinal cord injury in rats

Jia-Lin Song,Wei Zheng,Wei Chen,Yun Qian,Yuan-Ming Ouyang,Cun-Yi Fan 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Our study aims to explore the effects of lentivirus-mediated microRNA-124 (miR-124) gene-modified bone marrow mesenchymal stem cell (BMSC) transplantation on the repair of spinal cord injury (SCI) in rats. BMSCs were isolated from the bone marrow of rats. The target gene miR-124 was identified using a luciferase-reporter gene assay. Seventy-two rats were selected for construction of the SCI model, and the rats were randomly divided into the blank group, sham group, SCI group, negative control (NC) group, overexpressed miR-124 group and si-PDXK group. The mRNA expression of miR-124 and the mRNA and protein expression of pyridoxal kinase (PDXK) were detected by quantitative real-time polymerase chain reaction and western blotting. The locomotor capacity of the rats was evaluated using the Basso, Beattie and Bresnahan (BBB) scale. Brdu, neuron-specific enolase (NSE), neurofilament (NF) and microtubule-associated protein 2 (MAP2) were detected using immunohistochemistry. The expression levels of thyrotropin-releasing hormone (TRH), prostacyclin (PGI2) and gangliosides (GM) were measured using an enzyme-linked immunosorbent assay. PDXK was identified as the target gene of miR-124. The overexpressed miR-124 group exhibited higher miR-124 expression than the SCI, NC and si-PDXK groups. Compared with the SCI and NC groups, the PDXK expression was downregulated in the overexpressed miR-124 and si-PDXK groups, and the BBB scores were significantly increased 7, 21 and 35 days after transplantation. The double-labeled positive cell densities (Brdu+NSE/NF/MAP2) and the expression levels of TRH, PGI2 and GM in the overexpressed miR-124 group were significantly higher than those in the NC and SCI groups. These results indicated that miR-124 targeted PDXK to accelerate the differentiation of BMSCs into neurocytes and promote SCI repair.

Acupuncture for ventilator-dependent patients at a hospital-based respiratory care center: A randomized controlled trial

Jia-Ming Chen,Wan-Li Chiang,Bin-Chuan Ji,Ruei-Jhe Jhang,Pei-Hsin Chen,Ya-Lun Li,Che-Ju Chang,Sung-Yen Huang,Tsung-Chieh Lee,Chia-Yun Chen,Ching-Hsiung Lin,Sheng-Hao Lin 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.4

Background: In intensive care units, mechanical ventilation is an important therapy to help patients with dysp- nea. However, long-term ventilator dependence would consume huge medical resources and increase the risk of morbidity and mortality. The aim of the study was to examine the efficacy of the acupuncture combined with western medical care on ventilator parameters in ventilator-dependent patients. Methods: In this clinical trial, 80 ventilator-dependent patients aged 20 to 80 years old were randomly assigned to acupuncture group and control group in the respiratory care center (RCC) of Changhua Christian Hospital. Besides regular medical care and therapy, participants in the acupuncture group received acupuncture therapy at the same 17 acu-points for 20 minutes once a day, a total of 12 sessions. The ventilator parameters were recorded to evaluate the respiratory efficiency for all participants. The primary outcome was rapid shallow breathing index (RSBI), and secondary outcomes were respiratory rate (RR), tidal volume (TV) and ventilation per minute (MV). Results: Though there was no significant difference in the parameter between the acupuncture group and the control group, we found the trend of decreasing RSBI in the acupuncture group. In subgroup analyses, the mean of RSBI significantly decreased 16.02 (with the SD in 60.84) in acupuncture group, while it increased 17.84 (with the SD in 39.38) in control group (p = 0.036) after 12 sessions. Conclusion: Acupuncture treatment can improve breathing ability of patients with respirator dependence in respiratory care center.

New neo-lignan from Acanthopanax senticosus with protein tyrosine phosphatase 1B inhibitory activity

Jia Lin Li,Na Li,Shan-Shan Xing,Nan Zhang,BanBan Li,JianGuang Chen,안종석,Long Cui 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.11

New neo-lignan, (7S, 8R)-3-hydroxyl-4-methoxyl-balanophonin (1), together with seven known compounds(2–8)were isolated fromthe EtOAc-soluble extract ofAcanthopanax senticosus. The structure of the newneo-lignanwas elucidated with spectroscopic and physico-chemicalanalyses. All the isolates were evaluated for in vitro inhibitoryactivity against PTP1B, VHR and PP1. Among them, the newcompound (1) was found to exhibit selective inhibitoryactivity on PTP1B with IC50 value 15.2 ± 1.4 lM.