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      • KCI등재

        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.

      • KCI등재

        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.

      • KCI등재

        Relationship between Fractional Exhaled Nitric Oxide Level and Efficacy of Inhaled Corticosteroid in Asthma-COPD Overlap Syndrome Patients with Different Disease Severity

        Jia-Xi Feng,Yun Lin,Jian Lin,Su-Su He,Mei-Fang Chen,Xiao-Mai Wu,You-Zu Xu 대한의학회 2017 Journal of Korean medical science Vol.32 No.3

        This study explored the relationship between the fractional exhaled nitric oxide (FeNO) level and the efficacy of inhaled corticosteroid (ICS) in asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) patients with different disease severity. A total of 127 ACOS patients with ACOS (case group) and 131 healthy people (control group) were enrolled in this study. Based on the severity of COPD, the ACOS patients were divided into: mild ACOS; moderate ACOS; severe ACOS; and extremely severe ACOS groups. We compared FeNO levels, pulmonary function parameters including percentage of forced expiratory volume in 1 second (FEV1) to predicted value (FEV1%pred), ratio of FEV1 to forced vital capacity (FEV1/FVC), inspiratory capacity to total lung capacity (IC/TLC) and residual volume to total lung capacity (RV/TLC), arterial blood gas parameters, including PH, arterial partial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2), total serum immunoglobulin E (IgE), induced sputum eosinophil (EOS), plasma surfactant protein A (SP-A), plasma soluble receptor for advanced glycation end products (sRAGE), sputum myeloperoxidase (MPO), sputum neutrophil gelatinase-associated lipocalin (NGAL) and Asthma Control Test (ACT) scores, and COPD Assessment Test (CAT) scores. Compared with pre-treatment parameters, the FeNO levels, RV/TLC, PaCO2, total serum IgE, induced sputum EOS, plasma SP-A, sputum MPO, sputum NGAL, and CAT scores were significantly decreased after 6 months of ICS treatment, while FEV1%pred, FEV1/FVC, IC/TLC, PH, PaO2, plasma sRAGE, and ACT scores were significantly increased in ACOS patients with different disease severity after 6 months of ICS treatment. This finding suggests that the FeNO level may accurately predict the efficacy of ICS in the treatment of ACOS patients.

      • KCI등재

        Optimum control system for earthquake-excited building structures with minimal number of actuators and sensors

        Jia He,You-Lin Xu,Chao-Dong Zhang,Xiao-Hua Zhang 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.16 No.6

        For vibration control of civil structures, especially large civil structures, one of the important issues is how to place a minimal number of actuators and sensors at their respective optimal locations to achieve the predetermined control performance. In this paper, a methodology is presented for the determination of the minimal number and optimal location of actuators and sensors for vibration control of building structures under earthquake excitation. In the proposed methodology, the number and location of the actuators are first determined in terms of the sequence of performance index increments and the predetermined control performance. A multi-scale response reconstruction method is then extended to the controlled building structure for the determination of the minimal number and optimal placement of sensors with the objective that the reconstructed structural responses can be used as feedbacks for the vibration control while the predetermined control performance can be maintained. The feasibility and accuracy of the proposed methodology are finally investigated numerically through a 20-story shear building structure under the El-Centro ground excitation and the Kobe ground excitation. The numerical results show that with the limited number of sensors and actuators at their optimal locations, the predetermined control performance of the building structure can be achieved.

      • Benefit of Post-mastectomy Radiotherapy of the Supra-/infraclavicular Lymphatic Drainage Area in Breast Cancer Patients

        He, Zhen-Yu,Wu, San-Gang,Zhou, Juan,Sun, Jia-Yuan,Li, Feng-Yan,Lin, Qin,Guo, Ling,Lin, Huan-Xin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

        Background: This study investigated the survival benefit of radiotherapy (RT) of the supra- and infraclavicular lymphatic drainage area in Chinese women with T1-2N1M0 breast cancer receiving mastectomy. Methods: A total of 593 cases were retrospectively reviewed from 1998 to 2007. The relationship between supra- or infraclavicular fossa relapse (SCFR) and post-operative RT at the supra-/infraclavicular lymphatic drainage area was evaluated. Results: The majority of patients (532/593; 89. 8%) received no RT while 61 patients received RT. The median follow-up was 85 months. Among patients without RT, 54 (10. 2%) developed recurrence in the chest wall or ipsilateral SCFR. However, none of the 61 patients who underwent RT demonstrated SCFR. One patient who received RT (1. 6%) experienced recurrence in the chest wall. Univariate analysis revealed that age and molecular subtype (both P < 0. 05) were two prognostic factors related to supraclavicular and infraclavicular fossa relapse-free survival (SFRFS). Multivariate analysis revealed that only Her-2 positive status (P = 0. 011) was an independent predictor of SFRFS. RT had no influence on distant metastasis (P = 0. 328) or overall survival (P = 0. 541). SCFR significantly affected probability of distant metastasis (P < 0. 001) and overall survival (P < 0. 001). Conclusion: Although RT was not significantly associated with SFRFS, postoperative RT was significantly associated with a lower locoregional (i. e., supraclavicular/infraclavicular and chest wall) recurrence rate. SCFR significantly influenced distant metastasis-free survival, which significantly influenced the overall survival of T1-2N1M0 breast cancer patients after mastectomy. Thus, prophylactic RT is recommended in T1-2N1M0 breast cancer patients, especially those who have Her-2 positive lesions.

      • KCI등재

        Bamboo Charcoal/Quick-Dry/Metallic Elastic Knits: Manufacturing Techniques and Property Evaluations

        Jia-Horng Lin,Chih Hung He,Mong-Chuan Lee,Yueh-Sheng Chen,Ching-Wen Lou 한국섬유공학회 2019 Fibers and polymers Vol.20 No.7

        Protective clothing with electromagnetic shielding effectiveness (EMSE) is a functional textile, which shieldselectromagnetic waves to protect the human body from the far infrared rays. Traditional EMSE garments primarily usemetallic plates for reflecting electromagnetic interference (EMI). However, they also have disadvantages of a heavy weight,easy corrosion, and high production cost. In this study, three different functional yarns are combined, during which the twistnumber of metallic wires is changed for a better shielding effect. A crochet machine is used to fabricate functional elasticknits with the metallic composite yarns as the warp- and weft-inlaid yarns. The test results show that double (D) functionalelastic knits exhibit EMSE of above 20 dB when the EMI are between 1.0 and 3.0 GHz. In addition, the knit structure canimprove breaking tensile strength by 170 % and increases bursting strength by 58 %, but undermines the tear strength by10 %. Although changing twist number of metallic composite yarns does not affect water absorption rate along the weftdirection, it helps increasing elastic recovery rate by 3.1 %, water absorption rate along the warp direction by 106 %, farinfraredemissivity by 2.3 %, water vapor transmission rate by 20 %, and air permeability by 6 %.

      • SCIESCOPUSKCI등재

        Effects of Ginsenosides Rg1 on Osteoblasts Cultured with Ti Particles

        ( Yu Lin ),( Yin Sheng Wu ),( Jia Cheng He ),( Yun Mei Huang ),( Yan Ping Lin ) 한국응용약물학회 2012 Biomolecules & Therapeutics(구 응용약물학회지) Vol.20 No.1

        The aim of this study was to explore the role and effect of ginsenosides Rg1 on osteoblasts cultured with Ti particles. Osteoblasts from neonatal rats were cultured with particles and different doses of Rg1, the main active ingredient in ginsenosides Rg1. We found that the COX-2, PGE2, TNF-α, IL-1, and IL -6 concentrations in the medium of cells cultured with Ti particles significantly increased as compared with that of the control cells (p<0.05 or p<0.01). In addition, cells cultured with Ti particles alone exhibited the highest concentrations of these molecules. The PGE2, TNF-α, IL-1, and IL-6 levels in the medium of cells cultured with Rg1 were in between those of the control cells and the cells cultured with Ti particles alone. The IL-1ra level in the group cultured with Ti and medium-dose Rg1 was the highest followed by the cells cultured with Ti and high-dose Rg1 and those cultured with Ti and low-dose Rg1 (p<0.05). In conclusion, ginsenosides can reduce the levels of inflammatory cytokines produced by osteoblasts on induction with Ti particles and can prevent prosthesis loosening.

      • SCIEKCI등재

        Atrial fibrillation in critically ill patients who received prolonged mechanical ventilation: a nationwide inpatient report

        ( Zhen Lin ),( Hedong Han ),( Wei Guo ),( Xin Wei ),( Zhijian Guo ),( Shujie Zhai ),( Shuai Li ),( Yiming Ruan ),( Fangyuan Hu ),( Dongdong Li ),( Jia He ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.6

        Background/Aims: To evaluate temporal trends of atrial fibrillation (AF) prevalence in critically ill patients who received prolonged mechanical ventilation (MV) in the United States. Methods: We used the 2008 to 2014 National Inpatient Sample to compute the weighted prevalence of AF among hospitalized adult patients on prolonged MV. We used multivariable-adjusted models to evaluate the association of AF with clinical factors, in-hospital mortality, hospitalization cost, and length of stay (LOS). Results: We identified 2,578,165 patients who received prolonged MV (21.27% of AF patients). The prevalence of AF increased from 14.63% in 2008 to 24.43% in 2014 (p for trend < 0.0001). Amongst different phenotypes of critically ill patients, the prevalence of AF increased in patients with severe sepsis, asthma exacerbation, congestive heart failure exacerbation, acute stroke, and cardiac arrest. Older age, male sex, white race, medicare access, higher income, urban teaching hospital setting, and Western region were associated with a higher prevalence of AF. AF in critical illness was a risk factor for in-hospital death (odds ratio, 1.13; 95% confidence interval, 1.11 to 1.15), but in-hospital mortality in critically ill patients with AF decreased from 11.6% to 8.3%. AF was linked to prolonged LOS (2%, p < 0.0001) and high hospitalization cost (4%, p < 0.0001). LOS (-1%, p < 0.0001) and hospitalization cost (-4%, p < 0.0001) decreased yearly. Conclusions: The prevalence of comorbid AF is increasing, particularly in older patients. AF may lead to poorer prognosis, and high-quality intensive care is imperative for this population.

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