Total Number Of Operations Research Articles

Comparison of the Damage Results of Bullet and Pellet Ammunition in Firearm Injuries Causing Bone Fractures in the Extremities

Objective
 The spectrum of firearm injuries (FI) is broad and challenging for physicians in terms of diagnosis and treatment. The bullets and pellet ammunition used in FI exhibit different ballistic patterns and cause quite different damage to the body. The aim of this study was to compare the outcomes of bullet and pellet injuries causing bone fractures in the extremities.
 Methods
 The files of patients who were injured in their extremities due to civilian FI between 2016 and 2020 and who were followed up by the orthopedic clinic due to bone fractures were retrospectively analyzed. Age, gender, injured extremity, presence of infection, presence of vascular injury, presence of nerve injury, total number of operations, length of hospital stay and permanent sequelae were evaluated. Cases with missing files were excluded from the study. Evaluation criteria were compared under two main headings for bullet and pellet ammunition types.
 Results
 There were a total of 40 cases with a mean age of 43.5 years. The mean follow-up period was 41.5(24-61) months. 39 of the cases were male and 1 was female. There were 28 bullet injuries and 12 pellet injuries. Thirty-two of the cases were lower extremity injuries and 8 were upper extremity injuries. There were significant differences between ammunition type and number of operations (p=0.032).The length of hospital stay was significantly higher in the pellet group (p=0.024, p=0.024. Overall, 12.5% infection, 10% vascular damage, 17.5% nerve damage and 30% permanent sequelae occurred as a result of treatments. There were no significant differences between the groups in terms of infection, vascular injury, nerve injury and permanent sequelae.
 Conclusion
 When comparing the clinical outcomes of bullets and pellet ammunition, there were many differences in the severity of the injury and the treatment process.

Cross Entropy in Deep Learning of Classifiers Is Unnecessary-ISBE Error Is All You Need.

In deep learning of classifiers, the cost function usually takes the form of a combination of SoftMax and CrossEntropy functions. The SoftMax unit transforms the scores predicted by the model network into assessments of the degree (probabilities) of an object's membership to a given class. On the other hand, CrossEntropy measures the divergence of this prediction from the distribution of target scores. This work introduces the ISBE functionality, justifying the thesis about the redundancy of cross-entropy computation in deep learning of classifiers. Not only can we omit the calculation of entropy, but also, during back-propagation, there is no need to direct the error to the normalization unit for its backward transformation. Instead, the error is sent directly to the model's network. Using examples of perceptron and convolutional networks as classifiers of images from the MNIST collection, it is observed for ISBE that results are not degraded with SoftMax only but also with other activation functions such as Sigmoid, Tanh, or their hard variants HardSigmoid and HardTanh. Moreover, savings in the total number of operations were observed within the forward and backward stages. The article is addressed to all deep learning enthusiasts but primarily to programmers and students interested in the design of deep models. For example, it illustrates in code snippets possible ways to implement ISBE functionality but also formally proves that the SoftMax trick only applies to the class of dilated SoftMax functions with relocations.

Certification and labeling of organic products in European countries: experience for Ukraine

EU countries are currently one of the leading centers of development of the world market of organic agriculture products. The European countries with the largest sales markets for organic food products are Germany, France (EUR 9.1 billion), Italy (EUR 3.5 billion), Switzerland (EUR 2.7 billion). This activity is regulated in detail by the EU legislation: uniform standards are established in the field of production and processing of organic products, the rules for its marking, and the procedure for certification in this field. As rightly noted in the scientific literature, the detailed legal procedure of organic production is a guarantee of consumer rights protection from unscrupulous producers. In addition, almost every EU country has a fairly extensive system of private certification bodies, as well as its own standards, often stricter than the European ones. All this indicates the prestige of the consumption of organic products by the population and, accordingly, quite significant competition among its producers, who do not just try to comply with EU standards, but constantly improve them by obtaining appropriate national certificates. Unfortunately, in Ukraine, and in pre- war times, such production was not particularly popular. As of December 31, 2021. according to the Ministry of Agrarian Policy and Food of Ukraine (hereinafter referred to as the Ministry of Agrarian Policy), the total area of agricultural land used for organic production and the transition period was 422,299 hectares (1% of the total area of such land in Ukraine), including the area of agricultural land with organic status is 370,110 hectares, the area of the corresponding land in the transition period is 52,189 hectares. The total number of operators was 528, including 418 agricultural producers. But, taking into account the important role of organic farming, especially in the process of greening agriculture, ensuring soil fertility, protecting the environment, its role, especially in the post-war period, should grow. Therefore, the study of the legal regulation of the certification procedure in this area, on the example of the leading European countries, is particularly relevant.

Abstract 13650: Trends in Women Cardiac Operators of Structural and Interventional Procedures in the United States

Background: Women have historically been underrepresented in cardiology workforces. Throughout the United States, there is a major underrepresentation of women in cardiology as operators within structural proceduralists and interventional cardiology (IC). Methods: We extracted data from the Medicare Provider Utilization and Payment Database (MPUPD) from 2013 to 2020. The MPUPD is an administrative database of services rendered to Medicare patients enrolled in a fee-for-service program. We sought operators who performed >10 procedures using procedure codes for percutaneous transcatheter closure of congenital atrial septal defect (ASD) with implant and percutaneous coronary intervention, transcatheter mitral valve replacement via transcutaneous edge to edge repairs (TEER), and percutaneous left atrial appendage closure (PLAAO) using relevant CPT codes. The proportion of women operators was analyzed across the 8-year period. Results: Between 2013 and 2020, women on average represented 3.02% of the 1,260 cardiac operators identified. Despite the number of total structural operators performing 10 or more procedures increasing from 9 to 871 over the 8-year period, the proportion of women remained unchanged at less than 4.5% (P = 0.712) (Figure 1). By procedure, the total ASD, TEER, and PLAAO operators have increased, though the proportion of women operators remained constant over time (P = .913, .725 and .891). Over the studied period, there were no women operators identified with over 10 operations in 28 states (56%) for any structural procedures, 49 states (98%) for ASD procedures, 39 states (78%) for TEER, and 33 states (66%) of PLAAO. Conclusion: Women continue to represent an overwhelming minority of structural cardiac operators. Despite a rapid rise in the total number of operators, the proportion of female operators has not increased. Prospective studies are needed to investigate the underlying factors contributing to these sex-related differences.

THE EFFECT OF THE ECONOMIC CRISES AFTER 2000 ON PRIVATE HOSPITALS IN TURKEY

A local or global economic crisis has serious economic consequences. The severity and duration of crises, which may occur due to more than one factor, may vary depending on these factors. The economic crisis has a negative impact on the health sector as well as all other sectors. The main purpose of the study is to determine the effect of the economic crises after 2000 on private hospitals in Turkey. For this purpose, a total of fourteen parameters such as the number of private hospitals, the number of beds, the total number of imaging, the number of applications to the physician, the number of inpatients, the total number of operations and the number of physicians were examined. Within the scope of the study, document analysis was carried out as a method. Health Statistics Annuals (2020) belonging to the Ministry of Health were taken as a basis in the said document review. When we look at the historical background of Turkey, it is seen that there was an economic crisis in 2001, 2008 and 2016. The 2001 crisis was excluded due to insufficient data. It has been observed that the number of private hospitals in Turkey has increased every year, regardless of the crisis. No effect of the 2008 crisis on the analyzed parameters was observed. When the parameters are evaluated, it was determined that the economic crisis experienced only in 2016 had a negative impact on private hospitals. This crisis had a negative impact on eight of the fourteen parameters examined.

Evaluating and Enhancing the Operational Performance of Public Bus Systems Using GIS-based Data Envelopment Analysis

In this paper, the baseline performance level of Al Ain Public Bus Service is evaluated using Data Envelopment Analysis (DEA) based on some selected input (travel time per round trip, total number of stops, total number of operators, total number of buses) and output (daily ridership and vehicle-kilometer) variables. Two types of scenarios were developed and tested. The first set of scenarios aimed at investigating the possibility of reducing the operating cost while maintaining the same performance levels (efficiency and effectiveness) for the routes. The second set of scenarios was used to demonstrate how the baseline performance levels can be improved by slightly altering the route alignment (and subsequently input and output variables). Sensitivity analysis was then conducted to measure the efficiency and effectiveness of each route. Conclusions on how the transit authority can reduce daily operating hours while maintaining the existing performance level are made. Also, suggestions are presented on how to improve the overall performance level of the bus service by changing some route characteristics.

Surgical Experience Disparity Between Male and Female Surgeons in Japan

Women are vastly underrepresented in surgical leadership and management in Japan. The lack of equal opportunities for surgical training is speculated to be the main reason for this disparity; however, this hypothesis has not been investigated thus far. To examine gender disparity in the number of surgical experiences among Japanese surgeons. This retrospective, multicenter cross-sectional study used data from the National Clinical Database, which contains more than 95% of all surgical procedures in Japan. Participants included male and female gastroenterological surgeons who performed appendectomy, cholecystectomy, right hemicolectomy, distal gastrectomy, low anterior resection, and pancreaticoduodenectomy between January 1, 2013, and December 31, 2017. Differences in the number of surgical experiences between male and female surgeons. The primary outcomes were the total number of operations and number of operations per surgeon by gender and years of experience. Data were analyzed from March 18 to August 31, 2021. Of 1 147 068 total operations, 83 354 (7.27%) were performed by female surgeons and 1 063 714 (92.73%) by male surgeons. Among the 6 operative procedures, the percentage of operations performed by female surgeons were the highest for appendectomy (n = 20 648 [9.83%]) and cholecystectomy (n = 41 271 [7.89%]) and lowest for low anterior resection (n = 4507 [4.57%]) and pancreaticoduodenectomy (n = 1329 [2.64%]). Regarding the number of operations per surgeon, female surgeons had fewer surgical experiences for all 6 types of operations in all years after registration, except for appendectomy and cholecystectomy in the first 2 years after medical registration. The largest gender disparity for each surgical procedure was 3.17 times more procedures for male vs female surgeons for appendectomy (at 15 years after medical registration), 4.93 times for cholecystectomy (at 30-39 years), 3.65 times for right hemicolectomy (at 30-39 years), 3.02 times for distal gastrectomy (at 27-29 years), 6.75 times for low anterior resection (at 27-29 years), and 22.2 times for pancreaticoduodenectomy (at 30-39 years). This cross-sectional study found that female surgeons had less surgical experience than male surgeons in Japan, and this gap tended to widen with an increase in years of experience, especially for medium- and high-difficulty operations. Gender disparity in surgical experience needs to be eliminated, so that female surgeons can advance to leadership positions.

Immediately Sequential Bilateral Cataract Surgery: the Opinion of Russian Ophthalmologists

Purpose. A study of the attitude of Russian ophthalmologists to Immediately Sequential Bilateral Cataract Surgery (ISBCS).Methods. The study was carried out with the participation of 184 ophthalmologists actively performing cataract surgery, who were presented (in personal contact or via the Internet) a questionnaire developed by the authors, based on three main sections (“I use ISBCS in practice”; “I do not use ISBCS in practice”; “I don’t use, but I did ISBCS before”), which includes in each of the sections a number of clarifying questions and possible answers (“Doesn’t matter”; “Matters”; “Important”; “Very important”). At the same time, the analysis of possible answers was carried out by summing up two possible options — “Negative” opinion (“Not important” + “Matters”) and “Positive opinion” (“Important” + “Very important”). The age of the interviewed ranged from 26 to 58 years (mean age 36.2 ± 1.9 years), the experience of surgical activity in performing cataract phacoemulsification was predominantly (76 %) more than 5 years.Results. The data obtained indicate that 36 respondents (19.8 %) use ISBCS in their practice, 114 (61.8 %) do not use ISBCS; 34 (18.4 %) — do not use, but previously used ISBCS. At the same time, the volume of ISBCS performed on the same day is (for 84 % of respondents) no more than 20 % of the total number of operations performed. As part of the assessment of the main factors, in accordance with which (according to the ophthalmic surgeon), the patient is offered to perform ISBCS by the leader (in terms of the ratio of “positive” and “negative” opinions) is less clinic visits, and less time spent for the patient. The leading reasons for refusal to perform ISBCS by ophthalmic surgeons who do not use this technology are the possible occurrence of endophthalmitis, the risk of errors in IOL calculation, and medical and legal problems.Conclusion. The conducted questioning of domestic ophthalmologists testifies to the low prevalence of ISBCS technology, which is mainly associated with the possible risks of postoperative infectious complications, the lack of a standard protocol for surgical intervention, as well as medical and legal aspects. For the wider use of ISBCS, especially in a difficult epidemiological situation, it is necessary to carry out a set of measures of medical, educational and medical and economic orientation.

Emergency Surgery in a Regional Hospital Before and During the COVID 19 Pandemic

Background In extraordinary situations the volume of work of all hospital services changes. The impact of the global COVID 19 pandemic, is classified as an international emergency situation. But, we do not know How did one regional hospital in Bosnia and Herzegovina cope with the COVID-19 pandemic in line with its capacities in terms of emergency surgery. Materials and Methods We used data from our surgical protocols – emergency surgery performed in our department during July and August in 2019 and 2020. We used descriptive statistics. Results: The total number of examinations in the emergency surgical clinic was almost the same. The number of admissions in the period in question in 2020 was 36% lower in relation to the control period. The total number of operations was 17% lower. The number of emergency operations was 39.3% lower. Conclusion: it may be said that emergency surgery functioned on a satisfactory level in our regional hospital, and that the results do not deviate significantly from data from the literature, except regarding emergency amputations and emergency surgery for malignant colorectal stenosis.

603 Timing of autologous spray cell suspension: better early than late

IntroductionAutologous spray cell suspension is associated with multiple beneficial outcomes, however, the optimal timing of use has not been determined. We examined the timing of spay cell application, and hypothesize that early (< 72 hr) use is associated with faster definitive wound coverage, impacting multiple clinical outcomes compared to late ( >72 hr) use of spray cells.MethodsA retrospective review of 28 patients with spray cell application from March 2020 -- May 2021 was conducted. Pediatric patients < 16 yrs (n=1) as well as deaths (n=2--including 1 withdrawal) were excluded, leaving 25 patients. Those that received spray cells early (< 72 hrs, n=14) were compared to late ( >72 hrs, n=11). Time to index operation, time to spray cell application, rate of complete wound coverage, number of OR trips required for wound closure, wound infection rates, LOS / %TBSA, and overall hospital LOS were examined.ResultsThere was no difference in demographics or % TBSA burn (21.4% vs. 23/5%), between early and late spray cell groups. The early group had a significantly faster time to index operation (1.2 dys vs. 2.5 dys P= .05), and faster time to spray cell application (1.6 dys vs. 18.1 dys P=.036) (Table 1). The early group had a greater wound coverage rate at index operation —64.2% complete coverage vs. 18.1% in the late group (p< .03). The total number of OR trips needed for wound coverage was less in the early group (1.5 trips / pt) vs. the late (7.0 trips / pt) P=0.03. The early group had less wound infections, a shorter LOS / % TBSA burn ( 0.83 dys vs. 1.85 dys P=0.005), and shorter overall LOS (16.5 dys vs. 46.9 dys P=0.03).ConclusionsAutologous spray cell use has multiple beneficial outcomes, however, the optimal timing of application has not been determined. We report that early (< 72 hr) application of spray cells is associated with greater rate of complete wound coverage at index operation, decreased total number of operations needed for wound coverage, less wound infections, shorter LOS / %TBSA, and shorter overall LOS. This is likely related to earlier definitive wound coverage and closure, which is afforded by the large expansion ratio of spray cells.

Застосування зовнішнього черезкісткового остеосинтезу в практиці спеціалізованого травматологічного відділення міської лікарні (на прикладі міської лікарні № 3 м. Краматорська)

Актуальність. При лікуванні переломів у деяких випадках з’являється можливість вибору способу остеосинтезу, що відображено в «Клінічних рекомендаціях з лікування переломів», затверджених Пленумом асоціації ортопедів-травматологів України 15.05.2013 р. З урахуванням цього важливо знати, яке місце займає кожен із варіантів остеосинтезу, зокрема зовнішній черезкістковий остеосинтез (ЧКО), у практиці травматологічних відділень. Мета дослідження: встановити частоту застосування ЧКО та його співвідношення з внутрішнім остеосинтезом у практиці травматологічного відділення міської лікарні. Матеріали й методи. Проведено ретроспективне дослідження за матеріалами травматологічного відділення КМУ «Міська лікарня № 3» м. Краматорська (лютий 2015 р. — січень 2017 р.). Здійснено тотальну вибірку операцій ЧКО (72 спостереження), досліджено співвідношення зовнішнього та внутрішнього остеосинтезу. Результати. Як основний варіант остеосинтезу при лікуванні переломів ЧКО застосовано в 53 випадках (73,6 %). При наслідках травм його використано в 11 (15,3 %) спостереженнях, як спосіб тимчасової фіксації — у 8 (11,1 %). ЧКО становив 31,9 % серед втручань на аналогічних сегментах (72 із 226, співвідношення — 1 : 2,14). Він виявився домінуючим при діафізарних переломах кісток гомілки (26 із 47, 1,24 : 1), переважав при переломах дистального епіметафізу променевої кістки (2 : 1) та п’яткової кістки (2,5 : 1). Співвідношення ЧКО та внутрішнього остеосинтезу при пошкодженнях надп’ятково-гомілкового суглоба становило 1 : 2,93 (14 проти 41). При лікуванні наслідків травм найбільш часто ЧКО застосовували при наслідках переломів діафіза стегнової кістки (6 спостережень — 8,3 %). Висновки. Зовнішній черезкістковий остеосинтез становив 31,9 % серед усіх операцій остеосинтезу. Як основний вид остеосинтезу ЧКО застосовано у 88,9 % випадків, в 11,1 % — як спосіб тимчасової фіксації. Найбільш часто ЧКО використовували при діафізарних переломах кісток гомілки, ділянки надп’ятково-гомілкового суглоба, дистального епіметафізу променевої кістки.

Fast Solver for Implicit Continuous Set Model Predictive Control of Electric Drives

This paper proposes a fast and accurate solver for implicit Continuous Set Model Predictive Control for the current control loop of synchronous motor drives with input constraints, allowing for reaching the maximum voltage feasible set. The related control problem requires an iterative solver to find the optimal solution. The real-time certification of the algorithm is of paramount importance to move the technology toward industrial-scale applications. A relevant feature of the proposed solver is that the total number of operations can be computed in the worst-case scenario. Thus, the maximum computational time is known a priori. The solver is deeply illustrated, showing its feasibility for real-time applications in the microseconds range by means of experimental tests. The proposed method outperforms general-purpose algorithms in terms of computation time, while keeping the same accuracy.

The Impact of the COVID-19 Pandemic on the Most Common Diagnoses in Pediatric Surgery: Abdominal Pain, Acute Scrotum, Upper and Lower Extremity Injuries—Tertiary Center Experience

Objective:The coronavirus disease-19 pandemic has brought new patterns of behavior among patients and their parents. The reorganization of the health care system has reduced the number of elective surgical procedures in Croatia. In our study, we were interested in whether the pandemic has caused a statistically significant decrease in the number of examinations of children in the emergency department according to the most common diagnoses in pediatric surgery and whether there was a decrease in the number of emergency surgeries.Materials and Methods:We retrospectively analyzed data from the Hospital Information System. The analysis included 15 months of the pre-coronavirus disease-19 period and 15 months of the coronavirus disease-19 period. The primary outcome of the study was to determine the cumulative number of all examinations and then to determine the number of examinations according to the most common diagnoses and, consequently, to determine whether there was a statistically significant decrease. The secondary outcome was to determine the cumulative number of all operations and then to determine the number of the most common emergency operations and, consequently, to see if there was a statistically significant decrease.Results:In the 15 months of the pre- coronavirus disease-19 period, a total of 33 646 children were examined in the emergency department, while in the coronavirus disease-19 period, 26 831 were examined (P = .010). Although a decrease was recorded in all categories, a statistically significant decrease was recorded for diagnoses of abdominal pain (P = .007) and lower extremity injuries (P = .014). The total number of operations, due to strict measures and reduction of the elective program, decreased statistically significantly in the coronavirus disease-19 period (P < .0001). The number of most common emergency operations did not decrease statistically significantly.Conclusion:This study represents the first longer, 15-month experience of a pandemic in the only and largest children’s hospital in Croatia. There is no doubt that coronavirus disease-19 had the effect of reducing the number of examinations in the emergency department for all the most common diagnoses, but the number of operations did not change significantly.

Evaluation of user interfaces of various flight controllers for UAV

Planning a flight task by a remote pilot is a very important stage in the process of preparing a flight of an unmanned aerial vehicle. The smallest mistakes made at the same time can lead to irreparable consequences for both the UAV and others. The number of remote pilot errors can be reduced by reducing the speed of flight task planning. However, in actual operation, this can slow down flight preparation and, as a result, reduce the efficiency of the process as a whole. Among other things, the speed of flight planning is influenced by the user interface itself, which is a means of communication between the remote pilot and the machine – the on-board flight controller It is known that human-machine communication interfaces are very diverse, but in general they should contribute to the smooth and error-free entry of the input information into the memory of the machine (flight controller), which will later serve as a guide for the machine in its actions. At the same time, there is insufficient evidence to apply quantitative interface assessments (assessments of means, rules and methods and techniques) to already known flight controllers. The paper presents the results of the analysis and research of the user interfaces of two flight controllers according to the criteria of ease of data entry during planning, the total number of operations during the planning of all flight stages, and the amount of work performed within each operation, as well as the level of visualization (display) of information on the monitor of the ground control station of the unmanned aerial vehicle. Relative weighting factors based on rating methods were applied to each of the mentioned criteria. After taking into account the results of the evaluation, the ratings of such dispatchers as Pixhawk and Veronte were established.

The Impact of the COVID-19 Pandemic on the Most Common Diagnoses in Pediatric Surgery: Abdominal Pain, Acute Scrotum, Upper and Lower Extremity Injuries-Tertiary Center Experience.

The coronavirus disease-19 pandemic has brought new patterns of behavior among patients and their parents. The reorganization of the health care system has reduced the number of elective surgical procedures in Croatia. In our study, we were interested in whether the pandemic has caused a statistically significant decrease in the number of examinations of children in the emergency department according to the most common diagnoses in pediatric surgery and whether there was a decrease in the number of emergency surgeries. We retrospectively analyzed data from the Hospital Information System. The analysis included 15 months of the pre-coronavirus disease-19 period and 15 months of the coronavirus disease-19 period. The primary outcome of the study was to determine the cumulative number of all examinations and then to determine the number of examinations according to the most common diagnoses and, consequently, to determine whether there was a statistically significant decrease. The secondary outcome was to determine the cumulative number of all operations and then to determine the number of the most common emergency operations and, consequently, to see if there was a statistically significant decrease. In the 15 months of the pre- coronavirus disease-19 period, a total of 33 646 children were examined in the emergency department, while in the coronavirus disease-19 period, 26 831 were examined (P = .010). Although a decrease was recorded in all categories, a statistically significant decrease was recorded for diagnoses of abdominal pain (P = .007) and lower extremity injuries (P = .014). The total number of operations, due to strict measures and reduction of the elective program, decreased statistically significantly in the coronavirus disease-19 period (P < .0001). The number of most common emergency operations did not decrease statistically significantly. This study represents the first longer, 15-month experience of a pandemic in the only and largest children's hospital in Croatia. There is no doubt that coronavirus disease-19 had the effect of reducing the number of examinations in the emergency department for all the most common diagnoses, but the number of operations did not change significantly.

Towards a software defect proneness model: feature selection

This article is focused on improving static models of software reliability based on using machine learning methods to select the software code metrics that most strongly affect its reliability.The study used a merged dataset from the PROMISE Software Engineering repository, which contained data on testing software modules of fiveprograms and twenty-onecode metrics. For the prepared sampling, the most important features that affect the quality of software code have been selected using the following methods of feature selection: Boruta, Stepwiseselection, Exhaustive Feature Selection, Random Forest Importance, LightGBM Importance, Genetic Algorithms, Principal Component Analysis, Xverse python.Basing on the voting on the results of the work of the methods of feature selection, a static (deterministic) model of software reliability has been built, which establishes the relationship between the probability of a defect in the software module and the metrics of its code. It has been shown that this model includes such code metrics as branch countof a program, McCabe’s lines of codeand cyclomatic complexity, Halstead’s total number of operators and operands, intelligence, volume, andeffort value.A comparison of the effectiveness of different methods of feature selection has been put into practice, in particular, a study of the effectof the method of feature selection on the accuracy of classification using the following classifiers: Random Forest, Support Vector Machine, k-Nearest Neighbors, Decision Tree classifier, AdaBoost classifier, Gradient Boosting for classification. It has been shown that the use of any method of feature selection increases the accuracy of classification by at least ten percentcompared to the original dataset, which confirms the importance of this procedure for predicting software defects based on metric datasets that contain a significant number of highly correlated software code metrics.It has been found that the best accuracy of the forecast for most classifiers was reachedusing a set of features obtained from the proposed static model of software reliability. In addition, it has been shown that it is also possible to use separate methods, such as Autoencoder,Exhaustive Feature Selection and Principal Component Analysis withan insignificant loss of classification and prediction accuracy.

The impact of COVID-19 pandemic on aortic valve surgical service: a single centre experience

BackgroundThe coronavirus-disease 2019 (COVID-19) pandemic imposed an unprecedented burden on the provision of cardiac surgical services. The reallocation of workforce and resources necessitated the postponement of elective operations in this cohort of high-risk patients. We investigated the impact of this outbreak on the aortic valve surgery activity at a single two-site centre in the United Kingdom.MethodsData were extracted from the local surgical database, including the demographics, clinical characteristics, and outcomes of patients operated on from March 2020 to May 2020 with only one of the two sites resuming operative activity and compared with the respective 2019 period. A similar comparison was conducted with the period between June 2020 and August 2020, when operative activity was restored at both institutional sites. The experience of centres world-wide was invoked to assess the efficiency of our services.ResultsThere was an initial 38.2% reduction in the total number of operations with a 70% reduction in elective cases, compared with a 159% increase in urgent and emergency operations. The attendant surgical risk was significantly higher [median Euroscore II was 2.7 [1.9–5.2] in 2020 versus 2.1 [0.9–3.7] in 2019 (p = 0.005)] but neither 30-day survival nor freedom from major post-operative complications (re-sternotomy for bleeding/tamponade, transient ischemic attack/stroke, renal replacement therapy) was compromised (p > 0.05 for all comparisons). Recommencement of activity at both institutional sites conferred a surgical volume within 17% of the pre-COVID-19 era.ConclusionsOur institution managed to offer a considerable volume of aortic valve surgical activity over the first COVID-19 outbreak to a cohort of higher-risk patients, without compromising post-operative outcomes. A backlog of elective cases is expected to develop, the accommodation of which after surgical activity normalisation will be crucial to monitor.

Minimizing the maximum flow time for flexible job shop problem with parallel machines

ABSTRACT This paper studies a flexible job shop problem with parallel machines considering release time. The objective aims to minimize the maximum flow time. Based on the specific characteristics of the problem, we find a property which can reduce the dimension of solution space to dimension, where is the total number of operations. To solve the small-scale problem, a branch-and-bound algorithm is proposed. For the medium-scale problem, a heuristic based on a differential evolution algorithm is proposed. The LSPT-DS heuristic is tried to solve the large-scale problem. Through computational experiments, the proposed algorithms are proved to be both effective and efficient in solving this flexible job shop problem. Besides experiments are also conducted to verify that the objective to minimize the maximum flow time is reasonable.

Совместное использование технологий OpenMP и MPI на узлах вычислительного кластера

This work is devoted to the problem of implementing an efficient parallel program that solves the asigned task using the maximum available amount of computing cluster resources in order to obtain the corresponding gain in performance with respect to the sequential version of the algorithm. The main objective of the work was to study the possibilities of joint use of the parallelization technologies OpenMP and MPI, considering the characteristics and features of the problems being solved, to increase the performance of executing parallel algorithms and programs on a computing cluster. This article provides a brief overview of approaches to calculating the sequential programs complexity functions. To determine the parallel programs complexity, an approach based on operational analysis was used. The features of the sequential programs parallelization technologies OpenMP and MPI are described. The main software and hardware factors affecting the execution speed of parallel programs on the nodes of a computing cluster are presented. The main attention in this paper is paid to the study of the impact on performance of computational and exchange operations number ratio in programs. To implement the research, parallel OpenMP and MPI testing programs were developed, in which the total number of operations and the correlation between computational and exchange operations are set. A computing cluster consisting of several nodes was used as a hardware and software platform. Experimental studies have made it possible to confirm the effectiveness of the hybrid model of a parallel program in multi-node systems with heterogeneous memory using OpenMP in shared memory subsystems, and MPI in a distributed memory subsystems

Incisional hernia after abdominal surgery in infants: A retrospective analysis of incidence and risk factors

PurposeIncisional hernia (IH) is a complication following abdominal surgery extensively studied in adults but less so in infants. This study aimed to identify the incidence, high risk diseases and risk factors of IH following abdominal surgery in infants. MethodsInfants undergoing abdominal surgery before the age of three years in our tertiary centre between 1998 and 2018 were included. Patient demographics, peri‑operative details and the course during follow up were retrospectively extracted from patient records. Multivariate logistic regression was performed to identify risk factors. ResultsThe incidence of incisional hernia was 5.2% (107/2055). Necrotizing enterocolitis (12%), gastroschisis (19%), and omphalocele (17%) had the highest incidences of IH. Wound infection (OR: 5.3, 95%-CI:2.9–9.5), preterm birth (OR: 4.2, 95%-CI:2.6–6.7) and history of stoma (OR 1.7, 95%-CI:1.1–2.8) were significant risk factors for IH. Whilst age at surgery, surgical approach and total number of operations did not significantly influence IH development. The IH resolved in 15% (16/107) without surgery. ConclusionOne in twenty infants experiences IH following abdominal surgery, which is higher than previously described. Understanding the incidence of IH and associated risk factors will allow physicians to identify infants that may be at increased risk for IH and to possibly act pre-emptively.