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1.
Heliyon ; 10(6): e27719, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38509950

ABSTRACT

The research article in hand provides a new mechanism that deals with the investigation of the triangular analytical fuzzy solutions (TAFS) of the two-dimensional fuzzy fractional order wave equation (2-D FFWE) through the Hukuhara conformable fractional derivative (HCFD) along with the concept of [gH] and [gH-p] differentiability. The mechanism consists of a fuzzy traveling wave method coupled with additive operating splitting (AOS). The procedure for the aforesaid mechanism starts with the extension of the HCFD to the fuzzy conformable fractional derivative (FCFD). Furthermore, some properties of FCFD that play a vital role in this study like, ([i-gH],[ii-gH],[i-p],[ii-p])-differentiability, switching point, fuzzy chain rule, and traveling wave method are discussed in detail. Further, fuzzy traveling wave method coupled with the procedure of the additive operating splitting (AOS) method is adopted to investigate the triangular analytical fuzzy solution of the Two-dimensional fuzzy wave equation (2-D FWE). Finally, some examples are provided that support our arguments.

2.
Sci Rep ; 14(1): 4816, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413614

ABSTRACT

Many real-world optimization problems, particularly engineering ones, involve constraints that make finding a feasible solution challenging. Numerous researchers have investigated this challenge for constrained single- and multi-objective optimization problems. In particular, this work extends the boundary update (BU) method proposed by Gandomi and Deb (Comput. Methods Appl. Mech. Eng. 363:112917, 2020) for the constrained optimization problem. BU is an implicit constraint handling technique that aims to cut the infeasible search space over iterations to find the feasible region faster. In doing so, the search space is twisted, which can make the optimization problem more challenging. In response, two switching mechanisms are implemented that transform the landscape along with the variables to the original problem when the feasible region is found. To achieve this objective, two thresholds, representing distinct switching methods, are taken into account. In the first approach, the optimization process transitions to a state without utilizing the BU approach when constraint violations reach zero. In the second method, the optimization process shifts to a BU method-free optimization phase when there is no further change observed in the objective space. To validate, benchmarks and engineering problems are considered to be solved with well-known evolutionary single- and multi-objective optimization algorithms. Herein, the proposed method is benchmarked using with and without BU approaches over the whole search process. The results show that the proposed method can significantly boost the solutions in both convergence speed and finding better solutions for constrained optimization problems.

3.
Int J Chron Obstruct Pulmon Dis ; 17: 2693-2699, 2022.
Article in English | MEDLINE | ID: mdl-36281227

ABSTRACT

Objective: To analyse the guiding value of procalcitonin (PCT) for the selection of ventilation switching points in sequential mechanical ventilation for patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and respiratory failure, and to provide a reference for the optimisation of mechanical ventilation for patients with COPD and respiratory failure. Methods: The study included 160 patients with an acute exacerbation of COPD complicated by respiratory failure who received sequential mechanical ventilation treatment. They were divided into two groups of 80 participants. The critical point of the pulmonary infection observation window (PIC) was used as the switching point for sequential mechanical ventilation treatment in the control group, and PCT clinical node was used as the switching point for sequential mechanical ventilation treatment in the observation group. The invasive ventilation time, non-invasive mechanical ventilation time, total mechanical ventilation time, intensive care unit (ICU) treatment time, complication rate and prognosis were compared for the two groups. Results: (1) There was no significant difference in the respiratory rate, heart rate, arterial systolic pressure, arterial oxygen partial pressure, arterial carbon dioxide partial pressure or pH value between the two groups after 1 day of treatment, and (2) invasive mechanical ventilation time, non-invasive mechanical ventilation time, total mechanical ventilation time, ICU treatment time and the incidence of complications were significantly different in the two groups (P = 0.0001). Conclusion: Detecting PCT can guide the selection of ventilation switching points in sequential mechanical ventilation therapy for patients with COPD with respiratory failure in the acute exacerbation stage, effectively reduce the misevaluation of PIC switching points so that patients can obtain stable criteria for judgement and effectively improve the efficiency and safety of mechanical ventilation treatment for patients in the acute exacerbation stage.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Respiratory Insufficiency , Humans , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/therapy , Procalcitonin , Carbon Dioxide , Respiratory Insufficiency/diagnosis , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy , Respiration, Artificial/adverse effects , Oxygen
4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-480755

ABSTRACT

Objective To investigate the influencing factors of successfully switching to sequential ventilation in patients with prolonged weaning due to acute respiratory failure (ARF) after thoracolaparotomy based on the initial rapid shallow breathing index (RSBI) at 60 min after spontaneous breathing trial (SBT), namely, the f/VT optimal value range of 80-120 times/ (min · L), thus providing the basis for determining the ideal timing of weaning in clinical practice.Methods A prospective observational study of sequential ventilation [RSBI during the initial SBT (60 min), 80-120 breaths/ (min · L)] was carried out in 42 patients on mechanical ventilation (≥ 48 h) due to post-thoracolaparotomy ARF in the ICUs.According to the duration of the mechanical ventilation, the patients were divided into 2 groups : successfully prolonged weaning group (≥ 7 days, n =24) and refractory weaning group (< 7 days, n =18).The patients with cardiac failure, aged less 18 or over 80, with hepatic dysfunction, or those needing gastrointestinal decompression after esophageal surgery or upper abdomen surgery were excluded.The demographics, APACHE Ⅱ scores and duration of mechanical ventilation of both groups were recorded, and the respiratory work and oxygen metabolism variables before the switch to sequential ventilation (within 24 hours after admission to ICU) and at the time of switching (24 hours in the ICU after admission) were recorded, respectively: clinical puhnonary infection score (CPIS), assessment of cough severity, pH, PaO2, PaCO2 and PaO2/FiO2;hemodynamic and microcirculation-related variables: HR, MAP, fluid balance, BNP and Lac;endocrine and metabolism variables : Hb, ALB and random serum cortisol (COR).The clinical features and the changes of the above-mentioned variables before and at the time of switching were compared between both groups.The independent sample t test was used for the single factor comparison and Mann-Whitney U test was applied to the non-normal distributions.The Fisher exact probability test was used for the single factor comparison of ranked data such as categorical variables.Results There were no significant differences in age, gender and severity of disease between two groups (P > 0.05);the successfully prolonged weaning group had longer duration of invasive mechanical ventilation and ICU stay compared with the refractory weaning group (P < 0.05).There were significant differences in cough severity, PaCO2, pH, HR and fluid balance between two groups before switching (P < 0.05).Compared with those before switching, in the refractory weaning group there were marked decrease in Lac (P < 0.05), obvious increase in cough severity, pH, Hb and ALB (P < 0.05), but there was no significant difference in COR (P > 0.05);while in the successfully delayed weaning group, there were significant decrease in CPIS, PaCO2, HR, MAP, BNP, fluid balance and Lac (P < 0.05), and cough severity, pH, ALB and COR showed an upward trend (P < 0.05).Conclusions The key of successful sequential ventilation is within the values of RSBI ranging from 80 to 120 times/ (min · L) during the initial SBT (60 min) selected as the switching point in patients with prolonged weaning after thoracolaparotomy.The major influencing factors for determining the ideal timing of switching include the matching status between respiratory endurance and respiratory work, the balance between myocardial strength and both cardiac preload and afterload, the severe disease associated with adrenal insufficiency, and malnutrition.

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