ABSTRACT
Nowadays, electricity has become an integral part of human lives. Most of our daily appliances, tools, and personal belongings are inseparable from electricity. To ensure a proper electricity distribution with an efficient transfer capability, Extra-High Voltage (EHV) transmission towers are needed. To design such a structure, it is of utmost importance to account for the cost of said tower. However, the process to estimate the cost of EHV transmission towers is both time-consuming and strenuous on human labor since a lot of consideration have to be taken. To overcome this, an imperative requirement exists for a prompt, precise, and automated tool to replace the existing manual cost estimation method. This research endeavor aims to craft a tool using support vector regression (SVR) with the capacity to prognosticate construction expenses for projects involving EHV transmission towers. The exploration of pertinent literature has enabled us to amass historical data and delineate the attributes essential for estimating costs linked to EHV transmission tower construction. The investigation delves into a comprehensive dataset spanning the past decade in Taiwan. Within this timeframe, 317 EHV transmission towers were erected between 2009 and 2019. However, 79 of these instances are excluded due to incomplete information, thereby yielding 238 viable datasets (comprising 75 % of the overall total) to underpin the development of the SVR model. By configuring the parameters to C = 0.2 and γ = 0.1, followed by 5-fold cross-validation, the resultant SVR model attains a remarkable prediction accuracy of 97.91 %, on average. As a result, the proposed SVR-based model can effectively and accurately predict the cost of constructing an EHV transmission tower project and reduce the time spent on estimation, thus contributing to the enhancement of the resilience and robustness of the transmission network system.
ABSTRACT
By adopting the concept of 'factory assembly followed by onsite installation,' construction industrialisation (CI) plays an increasingly important role in sustainable urban development. CI can enhance construction quality and efficiency while reducing environmental impacts. To promote the CI, several policy interventions have been developed and implemented in different countries and regions. This study reviews the global CI promoting regulations and policies to provide a comprehensive insight into its interrelationship and development tendency. The research selects 105 publications related to practical CI policy from widely utilised databases (i.e., Web of Science and Scopus). Based on the annual publication trend analysis, geospatial distribution, and citation analysis, seven interrelated critical CI policy formulation themes are identified and examined: regulatory policies, standardised policies, promotional policies, urban design and planning policies, technological policies, managerial and educational policies, and sustainability policies. In addition, internal correlations and mutual influence among these seven classified policies are explored and discussed, which helps scholars enhance their grasp of current CI policy research and guide future research. This review provides the research community and industrial practitioners with a comprehensive understanding of various CI-promoting policies and a roadmap to CI-promoting policy development and evaluation.
Subject(s)
Industrial Development , Policy , Sustainable DevelopmentABSTRACT
BACKGROUND: Chronic total occlusion (CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival. Although the success rate of CTO percutaneous coronary intervention (CTO-PCI) has improved, CTO-PCI remains technically challenging. The Fielder XT guidewire was designed for CTO lesions. To validate whether the use of the guidewire increases the success rate, we compared the results of CTO-PCI with or without the guidewire. We hypothesized that the use of Fielder XT guidewire can increase the success rate of CTO-PCI. AIM: To investigate whether the use of Fielder XT guidewire increases the final procedural success of CTO-PCI via the anterograde approach. METHODS: Between January 2013 and December 2015, a retrospective study was conducted on 1230 consecutive patients with CTO who received PCI via the anterograde approach at the General Hospital of Northern Theater Command. The patients were divided into an XT Group (n = 686) and a no-XT Group (n = 544) depending on whether Fielder XT guidewire was used. Both groups were compared for clinical parameters, lesion-related characteristics, procedural outcomes and in-hospital complications. The data were statistically analyzed using Pearson's χ 2 test for categorical variables, and Students' t test was used to compare the quantitative data. Significant independent factors and a risk ratio with 95% confidence interval (CI) were assessed by multivariate logistic regression analysis. RESULTS: In total, 1230 patients were recruited; 75.4% of the patients were male, and 55.8% of the patients were in the XT group. The overall success rate was 83.9%, with 87.8% in the XT group. Based on multivariate logistic regression analysis, factors positively associated with procedural success were the use of Fielder XT guidewire (P = 0.005, 95%CI: 1.172-2.380) and systolic blood pressure (P = 0.011, 95%CI: 1.003-1.022), while factors negatively associated with procedural success were blunt stump (P = 0.013, 95%CI: 1.341-11.862), male sex (P = 0.016, 95%CI: 0.363-0.902), New York Heart Association (NYHA) class (P = 0.035, 95%CI: 0.553-0.979), contrast amount (P = 0.018, 95%CI: 0.983-0.998) and occlusion time (P = 0.009, 95%CI: 0.994-0.999). No significant differences were found between the XT group and the no-XT group with respect to clinical parameters, lesion-related characteristics, coronary artery rupture [3 (0.4%) vs 8 (1.5%), P = 0.056], in-hospital death [2 (0.3%) vs 6 (1.1%), P = 0.079] or in-hospital target lesion revascularization [3 (0.4%) vs 7 (1.3%), P < 0.099]. However, there were significant differences between the groups with respect to success rate [602 (87.8%) vs 430 (79.0%), P < 0.001], procedure time [(74 ± 23) vs (83 ± 21), P < 0.001], stent length [(32.0 ± 15.8) vs (37.3 ± 17.6), P < 0.001], contrast amount [(148 ± 46) vs (166 ± 43), P < 0.001], post-PCI myocardial infarction [43 (6.3%) vs 59 (10.8%), P = 0.004], major adverse cardiovascular event [44 (6.4%) vs 57 (10.7%), P = 0.007], side branch loss [31 (4.5%) vs 44 (8.1%), P = 0.009], contrast-induced nephropathy [29 (4.2%) vs 40 (7.4%), P = 0.018] and no reflow [8 (1.2%) vs 14 (2.9%), P = 0.034]. CONCLUSION: The use of Fielder XT guidewire shortens the Procedure and increases the success rate of CTO-PCI, and is also associated with reduced complication rates.
ABSTRACT
OBJECTIVE: To evaluate the clinical outcomes of "one-time" versus staged multivessel stenting in elderly (≥ 60 years) patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and multivessel disease (MVD). METHODS: We analyzed data of consecutive NSTE-ACS patients with multivessel percutaneous coronary intervention (PCI) who were enrolled in General Hospital of Shenyang Military Region between 2008 and 2012. A total of 1090 eligible patients aged ≥ 60 were further categorized into "one-time" group (n = 623) and staged PCI group (n = 467) according to intervention strategy. The primary endpoint was composite outcome of myocardial infarction (MI) or cardiac death during 3-year follow-up. RESULTS: The estimated 3-year composite rate of cardiac death or MI was 7.0% in the staged PCI group and 9.5% in the "one-time" group (P = 0.110). Multivariate analysis confirmed the benefit of staged PCI on the primary events in the elderly (HR: 0.638, 95% CI: 0.408-0.998, P = 0.049). In a propensity score matched cohort, staged PCI was associated with lower rates of primary events (6.1% vs. 10.4%, P = 0.046) and MI (3.4% vs. 7.4%, P = 0.037) at three years. In addition, there were reduced trends in the stent thrombosis at 30 days (0.3% vs. 1.4%, P = 0.177) and at three years (1.1% vs. 2.4%, P = 0.199) in the staged PCI group. There was no significant difference in the 3-year target vessel revascularization (15.5% vs. 14.4%, P = 0.746). CONCLUSIONS: In elderly NSTE-ACS patients with MVD, staged PCI might be an optimal strategy associated with reduced long-term cardiac death or MI compared with "one-time" PCI strategy, which needs further confirmation.
