Research on Cold-Formed Steel Stiffened-Web Built-up I-Section Columns with Complex Edge Stiffeners

Zhuangnan Zhang,Yudong Li,Chungang Wang,Yikai Hao,Jianqiao Song,Qinglin Guo 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.1

A series of double-limbs built-up I-section simply supported specimens subjected to compression were examined. The test columns contained 18 concentric compression columns and 12 eccentric compression columns with three section forms respectively. The infl uence of web stiff eners on buckling mode, ultimate bearing capacity and interaction between limbs were studied. It was shown that stiff eners in web eff ectively decreased the element width-to-thickness ratio and increased the bearing capacity of built-up I-section columns. But when larger eccentricity made the moment control the failure of eccentric compression specimens, the bearing capacity of the specimens was not improved obviously by web stiff eners. Distortional buckling could replace local buckling to control the failure modes of columns. Compared with double-limbs channel steel built-up open-sections with complex edge stiff eners under the same steel quantity and eccentricity, the load carrying capacity of double limb Σ-shaped channel built-up sections increased from 4.4% to 20.3%. While for double limb channel with V-type web stiff ener sections, the increment was from 2.2% to 17.4%. Furthermore, parametric study of 90 Σ-shaped built-up section members was investigated to obtain the optimization proportion of the web sub-element and relationship of carrying capacity between single Σ-shaped section and double limb Σ-shaped I-section. Finally, the ultimate load-carrying capacity of built-up columns subjected to axial compression were calculated by two kinds of direct strength method formulas, which were compared with the tests values. The results showed that the method considered the interaction between distortional buckling and fl exural buckling could obtain conservative results.

Wavelength and Waveband Assignment for Ring Networks Based on Parallel Multi-granularity Hierarchical OADMs

Yongmin Qi,Yikai Su,Yaohui Jin,Weisheng Hu,Yi Zhu,Yi Zhang 한국전자통신연구원 2006 ETRI Journal Vol.28 No.5

In this paper we study the optimization issues of ring networks employing novel parallel multi-granularity hierarchical optical add-drop multiplexers (OADMs). In particular, we attempt to minimize the number of control elements for the off-line case. We present an integer linear programming formulation to obtain the lower bound in optimization, and propose an efficient heuristic algorithm called global bandwidth resource assignment that is suitable for the design of large-scale OADM networks.

Elbow flow analysis and optimal exhaust port profile design

Yang Xu,Shuhe Huang,Liwang Su,Xiangyu Zhang,Yikai Li 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.3

In this study, the exhaust port profile of a diesel engine was numerically analyzed and optimized. First, the elbow profile results show that the separation loss of lower profile plays the main role in overall separation loss, it decreases sharply and then slowly with an increase of r lower /d. Within the range of 0 ≤ r lower /d ≤ 5, the total secondary flow loss increases sharply and then slowly with an increase of r lower /d. Under the same condition of relative pressure difference and lower profile, the elbow discharge coefficient increases with an increase of d mid /r upper and remains almost constant when d mid /r upper >1. The maximum discharge coefficient under a certain r lower condition increases with an increase of r lower . Afterwards, the applicability of elbow profile results to exhaust port were verified and an exhaust port profile design method was established based on a circular arc profile. Finally the feasibility of exhaust port profile design method was verified experimentally.

Cycle-Consistent Generative Adversarial Network: Effect on Radiation Dose Reduction and Image Quality Improvement in Ultralow-Dose CT for Evaluation of Pulmonary Tuberculosis

Yan Chenggong,Lin Jie,Li Haixia,Xu Jun,Zhang Tianjing,Chen Hao,Woodruff Henry C.,Wu Guangyao,Zhang Siqi,Xu Yikai,Lambin Philippe 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.6

Objective: To investigate the image quality of ultralow-dose CT (ULDCT) of the chest reconstructed using a cycle-consistent generative adversarial network (CycleGAN)-based deep learning method in the evaluation of pulmonary tuberculosis. Materials and Methods: Between June 2019 and November 2019, 103 patients (mean age, 40.8 ± 13.6 years; 61 men and 42 women) with pulmonary tuberculosis were prospectively enrolled to undergo standard-dose CT (120 kVp with automated exposure control), followed immediately by ULDCT (80 kVp and 10 mAs). The images of the two successive scans were used to train the CycleGAN framework for image-to-image translation. The denoising efficacy of the CycleGAN algorithm was compared with that of hybrid and model-based iterative reconstruction. Repeated-measures analysis of variance and Wilcoxon signedrank test were performed to compare the objective measurements and the subjective image quality scores, respectively. Results: With the optimized CycleGAN denoising model, using the ULDCT images as input, the peak signal-to-noise ratio and structural similarity index improved by 2.0 dB and 0.21, respectively. The CycleGAN-generated denoised ULDCT images typically provided satisfactory image quality for optimal visibility of anatomic structures and pathological findings, with a lower level of image noise (mean ± standard deviation [SD], 19.5 ± 3.0 Hounsfield unit [HU]) than that of the hybrid (66.3 ± 10.5 HU, p < 0.001) and a similar noise level to model-based iterative reconstruction (19.6 ± 2.6 HU, p > 0.908). The CycleGAN-generated images showed the highest contrast-to-noise ratios for the pulmonary lesions, followed by the model-based and hybrid iterative reconstruction. The mean effective radiation dose of ULDCT was 0.12 mSv with a mean 93.9% reduction compared to standard-dose CT. Conclusion: The optimized CycleGAN technique may allow the synthesis of diagnostically acceptable images from ULDCT of the chest for the evaluation of pulmonary tuberculosis.

The role of acupuncture and moxibustion in the treatment, prevention, and rehabilitation of patients with COVID-19: A scoping review

Mengjuan Ren,Yunlan Liu,Xiaojia Ni,Zhuoran Kuang,Xufei Luo,Yikai Zhang,Huishan Li,Yaolong Chen 한국한의학연구원 2022 Integrative Medicine Research Vol.11 No.4

Introduction This study aims to summarize the available evidence and guideline/consensus recommendations for acupuncture and moxibustion in the treatment, prevention and rehabilitation of patients with coronavirus disease 2019 (COVID-19). Methods A scoping review was performed. Eight electronic databases and other related websites were searched. All studies related to acupuncture and moxibustion for COVID-19 were considered. Descriptive analysis was applied to analyze the all included studies and guideline recommendations. Results We ultimately included 131 eligible studies. The main topics of the included studies were the treatment (82.4%) and prevention (38.9%) of COVID-19. The most included studies were literature reviews (65, 49.6%), protocols of systematic reviews (20, 15.3%), and guidelines and consensuses (18, 13.7%). The 18 (13.7%) COVID-19 guidelines and consensuses included 47 recommendations on acupuncture and moxibustion, which focused on the treatment (21/47, 44.7%), rehabilitation (17/47, 36.2%) and prevention (6, 12.8%) of COVID-19 patients. Zusanli (ST36), Feishu (BL13), Guanyuan (RN4) were recommended mostly for the treatment, rehabilitation and prevention respectively. Conclusion Acupuncture and moxibustion are effective in the treatment of COVID-19 patients to some extent. However, more high-quality of clinical trials still needed to determine the feasibility of acupuncture and moxibustion in COVID-19 patients to better guide clinical practice. Study registration Open Science Framework Registries (Registration DOI: 10.17605/OSF.IO/Z35WN; https://osf.io/z35wn). Introduction This study aims to summarize the available evidence and guideline/consensus recommendations for acupuncture and moxibustion in the treatment, prevention and rehabilitation of patients with coronavirus disease 2019 (COVID-19). Methods A scoping review was performed. Eight electronic databases and other related websites were searched. All studies related to acupuncture and moxibustion for COVID-19 were considered. Descriptive analysis was applied to analyze the all included studies and guideline recommendations. Results We ultimately included 131 eligible studies. The main topics of the included studies were the treatment (82.4%) and prevention (38.9%) of COVID-19. The most included studies were literature reviews (65, 49.6%), protocols of systematic reviews (20, 15.3%), and guidelines and consensuses (18, 13.7%). The 18 (13.7%) COVID-19 guidelines and consensuses included 47 recommendations on acupuncture and moxibustion, which focused on the treatment (21/47, 44.7%), rehabilitation (17/47, 36.2%) and prevention (6, 12.8%) of COVID-19 patients. Zusanli (ST36), Feishu (BL13), Guanyuan (RN4) were recommended mostly for the treatment, rehabilitation and prevention respectively. Conclusion Acupuncture and moxibustion are effective in the treatment of COVID-19 patients to some extent. However, more high-quality of clinical trials still needed to determine the feasibility of acupuncture and moxibustion in COVID-19 patients to better guide clinical practice. Study registration Open Science Framework Registries (Registration DOI: 10.17605/OSF.IO/Z35WN; https://osf.io/z35wn).

Efficacy of acupuncture for cardiopulmonary cerebral resuscitation: A systematic review and meta-analysis

Liu Yunlan,Ren Mengjuan,Kuang Zhuoran,Luo Xufei,Li Huishan,Zhang Yikai,Wen Wanxin,Cai Yefeng,Ni Xiaojia,Chen Yaolong 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.1

Background: Cerebral resuscitation is one of the main therapeutic aims in the treatment of cardiac arrest (CA) patients who experience a return of spontaneous circulation (ROSC). However, the therapeutic effects of current treatments are not ideal. The purpose of this study was to evaluate the efficacy of neurological function of acupuncture combined with conventional cardiopulmonary cerebral resuscitationthe (CPCR) for patients after ROSC. Methods: Seven electronic databases and other related websites were searched to identify studies on acupuncture combined with conventional CPCR for patients after ROSC. R software was used to conduct a meta-analysis, and the outcomes that could not be pooled were analyzed using a descriptive analysis. Results: Seven RCTs involving 411 participants who had experienced ROSC were eligible for inclusion. The main acupoints were Neiguan (PC6), Shuigou (DU26), Baihui (DU20), Yongquan (KI1), and Sanyinjiao (SP6). Compared to conventional CPCR, acupuncture combined with conventional CPCR led to signifi- cantly higher Glasgow Coma Scale (GCS) scores on day 3 (mean difference (MD) = 0.89, 95% CI: 0.43, 1.35, I 2 = 0%), day 5 (MD = 1.21, 95% CI: 0.27, 2.15; I 2 = 0%), and day 7 (MD = 1.92, 95% CI: 1.35, 2.50; I 2 = 0%). Conclusion: Acupuncture-assisted conventional CPCR may have a potential role in improving neurologi- cal function in CA patients after ROSC, but the certainty of evidence is very low and more high-quality studies are required.