Optimization Criteria Research Articles

The Impact of Tranexamic Acid on Blood Loss Management in Primary Total Knee Arthroplasty: A Comprehensive Review.

Total knee arthroplasty (TKA) is a widely performed surgical procedure to restore function and relieve pain in patients with advanced knee arthritis. One of the key challenges in TKA is managing perioperative blood loss, which can lead to complications such as postoperative anemia and the need for blood transfusions. Tranexamic acid (TXA), an antifibrinolytic agent, has shown promising results in reducing blood loss and transfusion requirements in various surgical settings, including TKA. This comprehensive review synthesizes current evidence regarding the efficacy and safety profile of TXA in primary TKA. Mechanistically, TXA functions by inhibiting the breakdown of fibrin clots, promoting hemostasis, and minimizing blood loss. Clinical studies evaluating TXA in TKA have consistently demonstrated significant reductions in blood loss parameters, including total blood loss, postoperative drain output, and transfusion rates. Key findings highlight the efficacy of TXA across different dosing regimens and administration routes, with minimal associated risks of thromboembolic events or adverse effects. Comparative analyses with other blood conservation strategies underscore TXA's superiority in reducing transfusion requirements and its cost-effectiveness in clinical practice. The review also discusses current clinical guidelines and recommendations for TXA use in TKA, emphasizing optimal dosing strategies and patient selection criteria. Future research directions include exploring the long-term outcomes of TXA administration and its impact on functional recovery, and refining protocols to enhance its efficacy and safety further. In conclusion, TXA represents a valuable adjunct in blood loss management during primary TKA, offering substantial benefits in patient outcomes, healthcare resource utilization, and cost-effectiveness. Continued research efforts are warranted to optimize its use and expand its applicability in orthopedic surgery.

The American College of Radiology contrast-enhanced ultrasound Liver Imaging Reporting and Data System and its modified version in diagnosing hepatocellular carcinoma via Sonazoid: a meta-analysis.

The American College of Radiology (ACR) developed the contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) for pure blood contrast agents, but Sonazoid was not included. Modifications to LI-RADS have been proposed for Sonazoid. The purpose of this meta-analysis was to identify and compare the diagnostic efficacy of the two LI-RADS algorithms of Sonazoid. We searched the PubMed, MEDLINE, Web of Science, Embase, and Cochrane Library databases from databases inception to August 31, 2023, to find original studies on the ACR LI-RADS and/or modified LI-RADS algorithm with Sonazoid used as the contrast agent in patients with high-risk hepatocellular carcinoma (HCC). A bivariate random-effects model was used. Data pooling, meta-regression, and sensitivity analysis were performed for meta-analysis. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was used to assess the methodological quality, and the Deeks funnel plot asymmetry test was used to evaluate the publication bias. A meta-analysis of 10 studies with 1,611 observations was conducted. The pooled data for ACR LI-RADS category 5 (LR-5) and modified LR-5 were respectively as follows: pooled sensitivity, 0.70 [95% confidence interval (CI): 0.64-0.75] and 0.81 (95% CI: 0.76-0.86) (P<0.05); pooled specificity, 0.90 (95% CI: 0.82-0.94) and 0.87 (95% CI: 0.81-0.91) (P>0.05); and pooled area under the summary receiver operating characteristic curve, 0.84 and 0.91. The diagnostic performance of LI-RADS category M (LR-M) of the two algorithms was comparable. Study heterogeneity was observed. The results indicated that modified LR-5 algorithm demonstrated improved diagnostic sensitivity compared with the ACR LR-5 algorithm of Sonazoid, with differences observed between the different versions. Further research is needed to validate and explore the optimal diagnostic criteria for HCC using Sonazoid. Before the database search was conducted, this study was registered on PROSPERO (International Prospective Register of Systematic Reviews; CRD42023455220).

Histologic analysis of gonadal tissue in patients with Turner syndrome and Y chromosome material

This study investigates gonadal histology in individuals with Turner syndrome assigned female at birth and Y-chromosome material (TS+Y) who underwent prophylactic gonadectomy. Despite case reports suggesting spontaneous menarche and pregnancies in TS+Y, this research reveals the absence of germ cells, indicating low fertility likelihood. Germ cell neoplasia in-situ was present in some patients, emphasizing a non-negligible risk of cancer precursor. As no malignancies were found even in older individuals, the study challenges the immediate need for prophylactic gonadectomy upon TS+Y diagnosis. Limited fertility benefits are suggested, emphasizing the need for further research on optimal timing and criteria for the procedure.

Theoretical framework and inference for fitting extreme data through the modified Weibull distribution in a first-failure censored progressive approach

The importance of biomedical physical data is underscored by its crucial role in advancing our comprehension of human health, unraveling the mechanisms underlying diseases, and facilitating the development of innovative medical treatments and interventions. This data serves as a fundamental resource, empowering researchers, healthcare professionals, and scientists to make informed decisions, pioneer research, and ultimately enhance global healthcare quality and individual well-being. It forms a cornerstone in the ongoing pursuit of medical progress and improved healthcare outcomes. This article aims to tackle challenges in estimating unknown parameters and reliability measures related to the modified Weibull distribution when applied to censored progressive biomedical data from the initial failure occurrence. In this context, the article proposes both classical and Bayesian techniques to derive estimates for unknown parameters, survival, and failure rate functions. Bayesian estimates are computed considering both asymmetric and symmetric loss functions. The Markov chain Monte Carlo method is employed to obtain these Bayesian estimates and their corresponding highest posterior density credible intervals. Due to the inherent complexity of these estimators, which cannot be theoretically compared, a simulation study is conducted to evaluate the performance of various estimation procedures. Additionally, a range of optimization criteria is utilized to identify the most effective progressive control strategies. Lastly, the article presents a medical application to illustrate the effectiveness of the proposed estimators. Numerical findings indicate that Bayesian estimates outperform other estimation methods by achieving minimal root mean square errors and narrower interval lengths.

A mechanism-based optimization strategy with adaptive laser power for laser powder bed fusion

The presence of keyhole-induced porosity significantly limits the application of laser powder bed fusion (L-PBF) in the additive manufacturing industry. Typically, a trial-and-error approach is used to select the best printing strategies for material type, powder bed, and laser beam to optimize the manufacturing process. This paper proposes an optimization strategy that uses adaptive laser power based on key understanding of the physical mechanisms of keyhole fluctuations. We identify and analyze five stages of the keyhole pore formation process, including the "J"-like keyhole formation, keyhole closure, keyhole pore collapse, keyhole pore splitting, and keyhole pore motion. Our simulation results suggest that reducing the laser power at the onset of "J"-like keyhole formation is an appropriate optimization approach. We propose adaptive indices to quantify keyhole fluctuations and predict the onset of "J"-like keyhole formation, which facilitates the use of adaptive laser power for optimization. Two parametric studies are conducted to investigate the impact of the optimization criterion and laser power adjustment on keyhole instability. The results demonstrates that our optimization strategy can effectively stabilize the keyhole and reduce the occurrence of keyhole porosity.

Optimal Sensor Placement with Minimal Predicted Posterior Variance

The performance of each monitoring system critically depends on the sensor layout and typical optimization criteria are based on the accessibility to the structure on site, experience with similar structures, and an optimal signal-to-noise ratio. More advanced criteria aim to optimize the feature extraction process, and this paper aims to develop a sensor placement strategy for optimal damage diagnosis. The approach is based on Bayesian updating and the optimization goal is to find a sensor layout that is the most sensitive to small changes in the examined system parameters. It is shown that such layouts manifest themselves through a minimum variance in the posterior distribution. Using Kalman filters, the posterior variance can be “predicted” based on the measurement error and numerical models, so no data from and no simulations in the damaged state are required. By employing a polynomial chaos expansion (PCE)-based Kalman filter, the method becomes applicable for structures with many measurement channels, multiple examined system parameters, and for a large number of sensor combinations. Gaussian distributions are assumed for both system inputs and outputs. For proof of concept, the sensor placement is optimized on a numerical cantilever beam, demonstrating that the method can efficiently find the optimal sensor layout. Moreover, arbitrary measurement quantities (inclinations, vibrations, etc.) or damage-sensitive features (statistical values, modal parameters, etc.) can be used as observations, and multiple system parameters can be considered at the same time. Among other factors, an optimal sensor layout leads to large measurement responses, a small measurement error, and more advanced statistical quantities that will be elaborated on in detail.

Yacon powder mix: Effects of the composition and the process of microencapsulation by spray drying

Yacon is a tuber known as a healthy food due to its effects as an antidiabetic, anti-inflammatory, anticancer, and prebiotic agent; it is rich in fructooligosaccharides (FOS) and antioxidants, and due to its sweet taste and low-calorie content, it is used as a substitute for ordinary sugar. This research aimed to evaluate the influence of the composition of the feed and the microencapsulation process by spray drying (SD) on the properties of a yacon powder mixture (YP). Response surface methodology with a central composite design with a face-centered composition (α = 1) was used, considering the independent variables: inulin (IN) (3–5% w/w), maltodextrin (MD) (3–5% w/w), air inlet temperature (AIT) (140–160 °C), air outlet temperature (AOT) (75–85 °C) and atomizer disc speed (ADS) (18000–22000 rpm), and the dependent variables: moisture (Xw), water activity (aw), hygroscopicity (Hy), solubility (S), particle size (percentile D10, D50, and D90), total phenols (TP), antioxidant capacity (ABTS and DPPH), color (CIE-Lab*) and yield (Yi). The suspension formulation contained xanthan gum (0.167 %) and a mixture of ascorbic and citric acids (0.3 %). The aw and Xw values of the YP guarantee its microbiological stability; however, the process formulation produces a complex matrix (FOS- sugars- MD - IN) with high affinity for water, which favors adsorption phenomena (hygroscopic material) and high reconstitution (high solubility). The independent variables that best fit the experimental optimization criteria were: IN = 3.0 %, MD = 5.0 %, AIT = 143.7 °C, AOT = 80.1 °C, ADS = 22000 rpm, where Yi = 84.2 %, and the quality of the YP: Xw = 2.4 %, aw = 0.220, Hy = 23.0 %, S = 96.9 %, D10 = 10.6 μm, D50 = 23.4 μm and D90 = 169.3 μm, TP = 1228.2 mg gallic acid equivalent/100 g, ABTS = 2295.9 mg Trolox equivalent (TE)/100 g, DPPH = 5192.3 mg TE/100 g, L* = 80.5, a* = 5.1 and b* = 17.4. SD is an effective technology that positively impacts the development of new food products. In addition, the YP could have multipurpose applications for the industry, generating value in this agri-chain.

Optimizing volumetric modulated arc therapy prostate planning using an automated Fine-Tuning process through dynamic adjustment of optimization parameters

In radiotherapy treatment planning, optimization is essential for achieving the most favorable plan by adjusting optimization criteria. This study introduced an innovative approach to automatically fine-tune optimization parameters for volumetric modulated arc therapy prostate planning, ensuring all constraints were met. A knowledge-based planning model was invoked, and the fine-tuning process was applied through an in-house developed script. Among 25 prostate plans, this fine-tuning increased the number of plans meeting all constraints from 10/25 to 22/25, with a reduction in mean monitor units per gray without increasing plan’s complexity. This automation improved efficiency by saving time and resources in treatment planning.

Метод оценки критериев оптимизации системы электробезопасности в инфраструктуре села

The article provides an analysis of the state of energy availability and equipment of electric installations for infrastructure facilities in rural settlements. The main type of technogenic hazards is marked – the electrical hazard that occurs in emergency modes of operation of electrical installations. The conditions for solving the safety problem and choosing the optimal variant of the electrical safety system are given. The indicators of the technical efficiency of the electrical safety system are determined, characterized by the likelihood of electrical injury to a person and the likelihood of a fire in electrical installations at facilities. The choice of the most appropriate options for the use of electrical protection equipment, providing for the joint use of automatic switches and protective shutdown devices, was made as a result of comparing the likelihood of electrical injury and fire with a normalized risk level of electrical and fire safety. A method for optimizing the electrical safety system is considered according to two particular criteria representing the average values of the probabilities of electrical injury and fire with the equivalence of their values. The task of optimizing the security system is indicated, which consists in constructing a vector criterion of optimality and converting it into a scalar criterion using the "assignment" method to obtain a normalized partial criterion. The normalized private criteria of electrical and fire safety are determined using a scalar criterion for the selection of electrical protection options for an agricultural facility. An algorithm for evaluating the effectiveness of the electrical safety system in dangerous situations of electrical injuries has been built. The description of the construction of an algorithm for modeling the state of fire safety of the system in the event of fires in electrical installations is given. A comprehensive assessment of the normalized criterion for optimizing the electrical safety system was obtained according to two normalized criteria for electrical and fire safety and the choice of optimal electrical protection options at the studied facility. Keywords: TECHNOGENIC HAZARD, ELECTRICAL INSTALLATION, ACCIDENT, ELECTRICAL INJURY, TECHNICAL EFFICIENCY, EVALUATION CRITERIA, OPTIMIZATION OF ELECTRICAL SAFETY SYSTEM, ELECTRICAL PROTECTION

COMPARATIVE ANALYSIS OF THE EFFICIENCY OF PARABOLIC AND TRAPEZOIDAL SECTIONS IN IRRIGATIONCANALS

One of the current scientific directions in hydraulic engineering is to give irrigation canals a hydraulically and statically stable cross-sectional shape in the form of the most advantageous parabolic profile. This approach allows maximizing the sediment transport capacity of the flow and significantly reducing the time and costs of construction and maintenance works, using optimization criteria for next-generation machinery and mechanisms. The significance of this research lies in developing a new concept for designing, constructing, and operating irrigation canals in hydraulic engineering systems with cross-sectional shapes that are both hydraulically and statically stable. These shapes aim to maximize sediment transport capacity, ensure ecological sustainability of natural-technical basin systems, and contribute to national food security. The objects of study are hydraulic engineering structures, specifically the inter-farm canals of irrigation systems within the Syr Darya river basin in the southern region of the Republic of Kazakhstan. For the study, methods were used including stability analysis of earth slopes using circular-cylindrical sliding surfaces, methods based on analogy between shear curves and slopes, and methods based on the theory of limit equilibrium. Calculations have demonstrated the advantages, including increased resistance to cross-section deformation, reduced earthwork volumes during irrigation canal construction and cleaning by 20-25%, decreased materials and work volume for possible lining by 13-18%, narrower canal top width and land acquisition zones by 11-17%, lower labor costs by 13-16%, reduced construction costs by 14-18%, and decreased specific adjusted costs by 15-18%.

SCIENTIFIC APPROACH TO REDUCING THE ENERGY OF THE PARKING RETARDER POSITION OF A SORTING DEVICE WITH TARGET GRAVITY BRAKING OF CUTS

The main disadvantage of a sorting device with target gravity braking of cuts is the necessity to use a powerful parking retarder position. In order to reduce the energy of this position, it is proposed to install an auxiliary brake position on the descending part of the device to transfer there part of the work on regulating the rolling speed of cuts of a certain mass. For the given operating conditions, the required energy of these positions and the optimal design parameters of the sorting device were determined, and recommendations were developed for braking the cuts at the auxiliary brake position based on the results of simulation modeling of the rolling of the design runners. The structural parameters were optimized using the developed mathematical model, where the height of the sorting device is the optimization criterion. The optimization calculations were performed both for favorable and unfavorable conditions of the runners rolling. The results of the simulation modeling of the rolling of the design runners proved that the maximum braking value at the auxiliary brake position (0.74 m e. h.) for the specified operating conditions is provided when braking the cuts weighing more than 34.8 tons. To simplify the process of braking such cuts at the auxiliary braking position, it is proposed to use low-energy retarders whose rated energy is less than the maximum possible braking value at this position. The reason of it is that when more powerful retarders are used at the auxiliary braking position, not only the degree of braking of each cut should be determined, but also the duration of their braking, which to some extent complicates the process of speed control and may require automation of operation of this position. If low-energy retarders UVSK-11 with the rated energy of 0.6 m e. h. are used at the auxiliary brake position, the required energy of the park brake position is reduced by 0.57 m e. h. At the same time, all cuts weighing more than 30.8 tons should be braked at the auxiliary brake position. Based on the studies, it was concluded that the installation of an auxiliary brake position on the descending part of the sorting device with target gravity braking of cuts would reduce capital investments in construction and mechanization, as well as the costs associated with the operation of this device.

ОПТИМИЗАЦИЯ ПОСЛЕДОВАТЕЛЬНОСТИ ВЫПОЛНЕНИЯ ЗАКАЗОВ ПРЕДПРИЯТИЯ ЭВРИСТИЧЕСКИМИ АЛГОРИТМАМИ

The production process of fulfilling orders with parameters that require equipment readjustment is considered. The problem of determining the optimal strategy for the production equipment changeover is an optimization problem, which is formulated as a travelling salesman problem. When solving such a task, the graph nodes are orders, the arcs are changeovers with a known cost when moving from one order to another. The optimization criterion is the minimum total cost of equipment changeovers. Based on the cost matrix of equipment changeovers when executing orders with the known parameters, research is carried out to solve the problem using the 2-opt local search algorithm and the genetic algorithm. Examples are given for estimating the total cost of changeovers for orders that have several parameters with different levels. The steps for implementing heuristic algorithms to solve the problem are presented, and the results of experiments are shown.

Application of Sensory Methods to Evaluate the Effectiveness of Solutions to Reduce the Exposure to Odour Nuisance and Ammonia Emissions from the Compost Heaps.

Exposure to high concentrations of odours can result in health effects associated with direct health risks and irritation from nuisance. This investigation aimed to correlate aspects of the waste composting process with the emission levels of malodourous compounds. An essential optimisation criterion is the reduction of negative environmental impacts, particularly odour emissions. This study characterises odour concentration variations across various technological variants over different weeks of the composting process. A secondary objective is evaluating the efficacy of these variants, which differ in inoculation substances and compost heap composition. Olfactometric analyses were conducted using portable field olfactometers, enabling precise dilutions by mixing contaminated and purified air. The primary aim was to examine the correlation between selected odour parameters, determined via sensory analysis, and ammonia concentration during different composting weeks. Ammonia levels were measured using an RAE electrochemical sensor. Research shows that odour concentration is a significant indicator of compost maturity. In situ, olfactometric testing can effectively monitor the aerobic stabilisation process alone or with other methods. The most effective technological solution was identified by combining olfactometric and ammonia measurements and monitoring composting parameters, ensuring minimal odour emissions and the safety of employees and nearby residents.

Highly birefringent anti-resonant hollow-core fiber with meniscoid nested structure

We propose a meniscoid nested anti-resonant hollow-core fiber (MAF), wherein the fourfold rotational symmetry structure enables high birefringence and low loss in dual-wavelength range. Numerical investigation and simulation for variations in wall thickness along orthogonal directions are conducted, through which a formulated optimization criterion revealing the relationship between minimum difference in wall thickness and birefringence of 10−5 is obtained. A parameter of beat length to loss ratio η is defined to evaluate MAF performance with respect to birefringence and confinement loss (CL). With optimized MAF structure, the birefringence and CL are improved to 3.62 × 10−5 and 8.5 dB/km at 1.06 µm, 9.83 × 10−5 and 204.1 dB/km at 1.55 µm, respectively. Meanwhile, the bandwidths extend to 172 nm at 1.06 µm and 216 nm at 1.55 µm, and the superior bending resistance characteristics are validated. Our work offers valuable guidance for designing and optimizing highly birefringent anti-resonant hollow-core fiber (ARF), and the proposed MAF has great potential in polarization-dependent transmission and interferometric fiber gyroscopes.

On the faecal detection of Halicephalobus gingivalis in equines in Iran.

The life-cycle of the parasitic forms of Halicephalobus gingivalis is yet to be fully understood. In cases where there is evidence to support the presence of eggs from this parasite or its DNA in the faeces of equines, a thorough investigation of the clinical status and gastro-intestinal tract of the affected animals is warranted, as well as detailed descriptions of the employed coprological technique. Since reports of the identification of H. gingivalis eggs in faeces are sparse, objective measurements and high-quality images must be provided, in order to ensure optimal criteria for classification. Regarding research concerning H. gingivalis, no piece of information should be regarded as superfluous.

Alcohol-associated liver disease: Emerging therapeutic strategies.

The large and growing burden of alcohol-associated liver disease-and the considerable burden of morbidity and mortality associated with it-has been a drive toward ongoing research into novel strategies for its treatment, with a particular focus upon alcohol-associated hepatitis (AH). Management of alcohol-use disorder forms the central pillar of alcohol-associated liver disease care, with evidence-based psychological and pharmacological approaches being well established, and certain models demonstrating improved clinical outcomes when hepatology and addiction services are co-located. Corticosteroids have previously been used somewhat indiscriminately in patients with severe AH, but effective tools now exist to assess early response (and limit futile ongoing exposure). Techniques to predict risk of corticosteroid-related infection are also available, although current clinical strategies to mitigate this risk are limited. A variety of novel therapeutic approaches to AH are at different phases of trials and evidence gathering, with some of the most promising signals related to cytokine manipulation, epigenetic modulation, and targeting of the gut microbiota (ie, by means of fecal microbiota transplant). While remaining an ongoing source of debate, early liver transplant in severe AH has grown in interest and acceptability over the past decade as evidence supporting its efficacy builds, in the process challenging paradigms about mandatory pretransplant sobriety periods. However, uncertainty remains regarding the optimal selection criteria, and whether liver transplant has a role for only a highly limited proportion of patients with AH or more widespread application. This review aims to provide an overview of this fast-moving field.

New specific primer matK and rbcL region for DNA barcode pitcher plant Nepenthes spathulata

Abstract. Utama MN, Etikawati N, Sugiyarto, Susilowati A. 2024. New specific primer matK and rbcL region for DNA barcode pitcher plant Nepenthes spathulata. Biodiversitas 25: 2515-2523. The matK and rbcL genes were proposed as the preferred plant barcoding loci by The Consortium for the Barcode of Life (CBOL). DNA barcoding efficiently identifies samples at the species level using short standard DNA sequences. The identification disclosure needs is an important basis given the confusion in systematics in Nepenthes spathulata. Therefore, this study aims to design matK and rbcL region-specific primers for DNA barcoding pitcher plants. The primary design uses Primer3Plus with a blueprint from the GenBank KDQ007081.1 for matK and MH346374.1 for rbcL. Following testing primary candidates with Oligo Analyzer and Primer-BLAST, the primers MkNs1, and RbNs4 were selected as the optimal criteria based on the values of ?G and primer specificity. Optimization of annealing temperature with PCR gradient shows that the temperature range 52-57°C produces a good band for both regions and corresponds to the matK and rbcL region with product sizes of 800-900 bp from seven samples, which could be observed from the gel electrophoresis. Sequence similarity using blast-N, the matK sequence has similarity to the N. spathulata matK gene of 99.64% and 99.63% for the rbcL gene of N. ventricosa x N. alata. This MkNs1 and RbNs4 primer can be used to discover the identity of N. spathulata and the Nepenthes genus.

Stereo visual-inertial localization algorithm for orchard robots based on point-line features

The vision-based localization of orchard mobile robots is an indispensable component of orchard intelligent management, applicable to scenarios such as navigation and harvesting. Due to the rugged terrain and lack of texture features in orchard environments, the accuracy of Visual-Inertial Odometry (VIO) based on feature point is compromised, making it challenging to meet practical application requirements. Addressing these issues, this paper proposes an algorithm for stereo visual-inertial localization based on point-line features, by enhancing VINS-Fusion. The algorithm incorporates the line feature detector algorithm (LSD) into the odometry front-end to detect line features, addressing the insufficient effective feature points and low-quality feature matching issues in orchard environments. Simultaneously, strategies for length filtering and feature matching are introduced for line features, eliminating poor-quality line features and matches caused by rugged terrain, thereby reducing adverse impacts on localization accuracy. To prevent keyframe redundancy due to a scarcity of stable feature points in areas with missing textures, such as tree trunks and leaves, a keyframe criteria optimization method based on point-line features is designed. Back-end optimization minimizes the cost function containing residuals of point-line features, prior information, and IMU, ultimately improving the localization accuracy of mobile robots. To validate the effectiveness and practicality of the proposed algorithm, a self-built dataset was created in real orchard environments, including scenes from banana plantation, mango orchard, and wampee orchard. Localization experiments were conducted using Rosario, EuRoC public datasets and self-built orchard dataset. Results indicate that the proposed algorithm consistently achieves lower ATE-RMSE than VINS-Fusion, with a maximum reduction of 79.2 % in the Rosario dataset sequence, 23.3 % in the EuRoC dataset sequence, and ATE-RMSE values of 0.091 m, 0.107 m, and 0.093 m in banana plantation, mango orchard, and wampee orchard, respectively. These represent reductions of 22.9 %, 7.6 %, and 27.3 % compared to VINS-Fusion. In the self-built orchard dataset, the average frame processing times for the algorithm front-end is 56.3 ms, while for the back-end is 31 ms, meeting the practical localization requirements. The proposed algorithm effectively enhances the localization accuracy of orchard mobile robots, offering a viable solution for autonomous navigation in orchard robot systems.

Flow and heat transfer mechanism and optimization design of spirally corrugated tubes

Abstract Spirally corrugated tubes are widely used as high-efficiency heat transfer tubes in various industrial production fields due to their simple manufacturing, low cost, and bi-directional enhanced heat transfer ability. In this study, numerical simulations were conducted on the flow in multi-start spirally corrugated tubes with an equivalent inner diameter of Di=20 mm. The effects of starts value of 1-8, pitch ratio p/Di of 1.5-3.0, ripple depth ratio e/Di of 0.05-0.20, and Reynolds number Re of 5000-3000 on the heat transfer and resistance characteristics of the multi-start spirally corrugated tubes were studied, and the mechanism of heat transfer enhancement was demonstrated by field synergy theory. In addition, through the performance evaluation standard PEC, the optimization design of the multi-start spirally corrugated tube was achieved. The research results indicate that increasing the start value and ripple depth improves heat transfer performance, despite higher flow resistance. As the pitch increases, the heat transfer performance decreases, and the flow resistance correspondingly decreases. When the start value is 8, p/Di=1.5, e/Di=0.20, and Re=20000, it is the optimal performance evaluation criteria (PEC) value, equal to 1.764. This will be of great significance for the design, manufacturing, and practical application of spirally corrugated tubes.

Алгоритмы построения дискретных приближенно Q-оптимальных планов эксперимента при активной идентификации регрессионных моделей многофакторных систем

In the theory of optimal experiment, there is a group of optimality criteria, for example, such as D-, A-, E-criteria, reflecting the accuracy of estimating model parameters. There is also a group of criteria related to the accuracy of the forecast based on the model, which can be characterized by the variance of estimates of mathematical expectations of responses. For example, using the G-optimality criterion allows you to obtain designs on which the constructed models will minimize the maximum variance of the forecast. Among these is the Q-optimality criterion, which assumes minimizing the average variance of the forecast for the regression model over the planning area. Most of the theoretical and applied research is related to the use of the D-optimality criterion. This is also explained by the fact that the criteria of D- and G-optimality are interconnected. At the same time, it should be noted that minimizing the maximum variance in the general case may not lead to a decrease in the average variance of the forecast area. In this regard, the use of Q-optimal designs in practical regression modeling tasks is relevant. For the widespread introduction into practice of the active identification of regression models of the concept of Q-optimality of experimental designs, an arsenal of effective algorithms for their construction is needed. The paper proposes and describes algorithms for constructing discrete approximate Q-optimal designs. The proposed algorithms are based on the developed approach of consistently increasing the number of points in the designs, as well as procedures for replacing points in the design. The designs obtained by such algorithms are recommended for use in practice when, on average, good prediction accuracy is required for the model over the entire range of input factors.