DEVELOPMENT OF BONOBO ALGORITHM AND ITS APPLICATION FOR OPTIMAL COORDINATION OF DIRECTIONAL OVERCURRENT RELAYS IN POWER SYSTEMS

In this paper, an improved Bonobo optimization algorithm (IBO) is proposed to solve the optimal coordination of directional overcurrent relays (DOCRs) problem. This problem is important for power system protection. It is considered a nonlinear and highly constrained optimization problem. IBO aims to improve the performance of the original Bonobo optimization algorithm (BO) using Levy flight distribution and three leaders selection. Both BO and IBO are utilized to develop two solvers for optimal coordination of DOCRs. The 15-bus and 30-bus test systems are used to validate BO and IBO in minimizing the total operating time of relays with satisfying the operational constraints. The results of the proposed IBO algorithm have been compared with the original BO algorithm and other well-known algorithms. The obtained results confirmed the effectiveness and superiority of the proposed IBO algorithm compared with the other algorithms in minimizing the total operating time of relays for the optimal coordination of DOCRs. Keywords: Directional overcurrent relays; Optimal coordination; Improved Bonobo algorithm; Levy flight distribution; Three leaders selection.

Development of an experimental-estimation method for estimating indices of residual life of a radio technical complex

To implement the operation of a radio technical complex according to its technical condition, it is necessary to jointly evaluate its reliability and residual life indices with required accuracy and reliability and minimization of the scope of special tests. The known methods are focused on separate solutions to the problems of estimating these indices as applied to the regulated strategy. To solve this problem, general provisions have been developed for estimating the indices of residual life of the radio technical complex including the accepted assumptions and limitations for developing the method, the estimated indices, and criteria of limiting state. The developed experiment-calculated method is a set of mathematical models of change of the reliability indices of a radio technical complex depending on calendar duration of operation or total operating time and analytical models of estimating the indices of its residual life. The mathematical models of change of mean time between failures, the probability of failure-free switching, and the parameter of the flow of failures of the radio technical complex depending on calendar duration of operation or the total operating time were presented in a form of regressive dependences. Analytical models of estimating the residual life indices are ratios for calculating the "average residual service life (resource)" according to the technical and economic criterion using regression-time dependences of the reliability indices. The developed experiment-calculated method can be used to estimate the indices of residual life of the radio technical complex with acceptable accuracy (no more than 2 quarters) and reliability (no worse than 0.8). In this case, the duration of the intervals of predicting the reliability indices should be 0.5 to 1 year and the corresponding observation intervals should be more than 1 year

Comparative Evaluation of Intra-Operative Adhesions in Post-Caesarean and Repeat-Caesarean Cases

BACKGROUND Adhesions after Caesarean section often create difficulties in subsequent Caesarean deliveries. Intra-operative adhesions result in delayed entry into the uterine cavity & subsequently baby-delivery, affecting neonatal morbidity; and on the other side – bladder / bowel injury, wound extensions, difficulty in uterine wound repair and uterine atony, affecting maternal morbidity. The study was conducted to comparatively evaluate the extent of intra-operative adhesions in post and repeat Caesarean cases and their impact over maternal and neonatal morbidity. METHODS The present prospective observational study consecutively recruited equal number (102) of post and repeat Caesarean cases, elective or emergency, over 10 months. Primary outcome measure was the presence & nature of intra-operative adhesions, evaluated with a pre-designed adhesion scoring system. Secondary outcome measures included baby delivery time, total operating time, neonatal Apgar-1, incidence of post-partum haemorrhage, bladder / bowel injury and Caesarean wound extension. P < 0.05 was considered significant for comparative evaluation. RESULTS Adhesions were found more significantly in post-Caesarean cases (χ 2 = 23.2385, P < 0.0001), and most were (59.1 %) of filmy type. Adhesion score was significantly higher in repeat-Caesarean group (P = 0.00694) because adhesions were mainly dense-type (59.5 %). In either group, however, adhesions between uterus and bladder were found predominant. In cases with adhesions, postCaesarean group shows significantly lesser Apgar-1 score (P < 0.0001), although median baby-delivery time was found comparable (P = 0.74896). Median total operating time was more in repeat Caesarean group, though not statistically significant (P = 0.11876); yet causing significantly more complications (P = 0.0252). CONCLUSIONS Intra-operative adhesions were more common in post-Caesarean cases, significantly affecting neonatal morbidity. Adhesions in repeat-Caesarean cases were mostly dense, significantly increasing total operating time and thereby maternal morbidity. KEYWORDS Intra-Operative Adhesions, Maternal and Neonatal Morbidity

Tubeless Supine Percutaneous Nephrolithotomy in Calyceal Diverticular Stone

Percutaneous Nephrolithotomy (PCNL) has routinely been performed in prone position as a treatment for calyceal diverticular stone. PCNL is performed supine as an alternate modality for calyceal diverticular stones. The objective of the procedure is to reduce operative time and anaesthetic morbidity during supine tubeless PCNL in calyceal diverticular stone. The series is about three patients with calyceal diverticular stones. These patients underwent supine tubeless PCNL in Galdakao modified supine Valdivia position. There was no intraoperative, postoperative or on follow-up complications in any of the the patients. In all the patients stones were cleared completely in single sitting. Supine PCNL in calyceal diverticular stone could be an alternative with similar outcomes to the standard prone PCNL. It provides an additional benefit of performing the procedure in a single position, which is known to reduce total operating time and also reduces anaesthesia complications.

Economically acceptable service life of mtz-80/82 tractors

Recently, the scientific and technical literature increasingly discusses the service life of agricultural machinery. Economically acceptable lifetimes of tractors and agricultural machines could exceed the amortization ones by 10-15 years. There is a correlation between the life of agricultural machinery and its annual output, which significantly affects the life and effectiveness of its use.(Research purpose). The research purpose is in studying the dependence of the annual running hours, the total cost of eliminating failures, and the cost of running time from the operating life in the range from 1 to 32 years. (Materials and methods) The study was conducted according to the reporting data of SCA "Malalla" and "Pervomaisk" of Batyrevsky district of the Chuvash Republic during 1998-2019. During the study, there were monitored 20 MTZ tractors for 20 years, and archived accounting data were also used. (Results and discussion) An analysis of the consumption of spare parts showed that the largest number of total spare parts falls on the interval of the service life of 17-19 years and operating time of 32-35 thousand of conventional hectares. The largest number of spare parts are spent on 14, 16 and 19 years of operation. For the first three years of operation, until the total operating time of 5850 conventional hectares, the total consumption of spare parts is of 15,410 rubles, which is 2.2 percent of the cost of a new tractor. (Conclusions) A study of the consumption of spare parts, tractor operating hours and the cost of operating hours by years of operation allows us to conclude that from 27 to 32 years of operation, with a total operating time of 46784 conventional hectares, despite the annual increase in the consumption of spare parts, its operating time begins to decrease, and the cost of an operating time unit increases sharply and reaches the operating time during the depreciation period and the total consumption of spare parts reaches the cost of a new tractor. Just at this time, it is necessary to stop the operation of the tractor. The results allow us to create recommendations to improve the efficiency of the operation and use of the machine and tractor fleet in agricultural organizations.

A Comparative Study of Hysteroscopic Morcellation or Resection of Uterine Polyps

Summary The aim of the study was to analyse the intraoperative parameters of hysteroscopic morcellation (HM) and conventional resectoscopy in the treatment of uterine polyps (UP). A total of 177 patients with ultrasound imaging of UP were included in a prospective study from February 2015 to February 2017. Out of them, 98 (55.4%) underwent HM and 79 (44.6%) had hysteroscopic resection (HR). We analyzed the following intraoperative parameters: total duration of the procedure, total operating time, time for dilation, actual operating time for HM/HR, the total amount of fluid distension media and fluid deficit. The mean operating time, measured as a total duration of the procedure, total operating time and actual operating time, was significantly shorter in the HM group, as compared to HR group, 8.27 and 19.48 minutes (min) – p<0.001, 6.15 and 16.33 min (p<0.001), 3.28 and 11.70 min (p<0.001), respectively. The total amount of fluid distension media was trustworthy lower in the HM group compared to HR, 446.02 ml and 2225.57 millilitres (ml) – p<0.001, respectively, as well as for the fluid deficit parameter – respectively 83.78 ml and 413.48 ml (p<0.001). This warrants the assumption that HM is an effective alternative to conventional resectoscopy for removal of UP with a favorable perioperative outcome.

REDESAIN KOMPOR BIOMASSA TIPE DOWNDRAFT SYSTEM CONTINUE DENGAN MENGGUNAKAN BAHAN SEKAM PADI

Kompor gasifikasi adalah salah satu teknologi pemanfaatan biomassa untuk keperluan memasak pada sektor rumah tangga. Gasifikasi biomassa merupakan suatu proses dekomposisi termal dari bahan-bahan organik melalui pemberian sejumlah panas dengan suplai oksigen terbatas untuk menghasilkan synthesis gases yang terdiri dari CO, H2, CH4 (selanjutnya disebut dengan syn-gas) sebagai produk utama dan sejumlah kecil arang karbon dan abu sebagai produk ikutan. Tujuan utama saya dalam menciptakan inovasi teknologi yang sedang berkembang saat ini supaya hasil yang didapat lebih efektif dan berkualitas. Metode penelitian yang digunakan dalam penelitian adalah metode eksperimen, diawali pengamatan dilapangan (observasi) kemudian dari sumber studi pustaka selanjutnya diaplikasikan dalam satu model dimensi dengan perencanaaan yang diwujudkan dalam satu bentuk nyata berupa prototipe kompor biomassa tipe downdraft system continue. Komsumsi bahan bakar berturut-turut didapat sebesar 0.00012 ; 0.00028 ; dan 0.00050 kg/hr. Total operating time dari kompor masing-masing sebesar 14; 16 dan 18 menit Power input berdasarkan hasil analisis masing-masing sebesar 0.00037 ; 0.00088 ; dan 0.00154 kW. Berdasarkan hasil analisis didapatkan power output terendah sebesar 7.3 ; 17.1 dan 30.5 kW. Efesiensi kompor biomassa tipe downdraft system continue pada penelitian adalah sebesar 23,6%.