A Procedure for the Fatigue Life Prediction of Straight Fibers Pneumatic Muscles

Different from the McKibben pneumatic muscle actuator, the straight fibers one is made of an elastomeric tube closed at the two ends by two heads that ensure a mechanical and pneumatic seal. High stiffness threads are placed longitudinally into the wall of the tube while external rings are placed at some sections of it to limit the radial expansion of the tube. The inner pressure in the tube causes shortening of the actuator. The working mode of the muscle actuator requires a series of critical repeated contractions and extensions that cause it to rupture. The fatigue life duration of a pneumatic muscle is often lower than traditional pneumatic actuators. The paper presents a procedure for the fatigue life prediction of a straight-fibers muscle based on experimental tests directly carried out with the muscles instead of with specimens of the silicone rubber material which the muscle is made of. The proposed procedure was experimentally validated. Although the procedure is based on fatigue life duration data for silicone rubber, it can be extended to all straight-fibers muscles once the fatigue life duration data of any material considered for the muscles is known.

DAMPAK TEKNIK SADAP SPIRAL TERHADAP PENERIMAAN PETANI KARET DI KABUPATEN TANJUNG JABUNG TIMUR

One of the way to increase rubber productivity and its production, is by focusing to recommended tapping techniques. In East Tanjung Jabung Regency although the recommended rubber tapping technique (i.e. spiral tapping technique) had been socialized, but there were still many rubber farmers who done a non-spiral tapping techniques. This will certainly affect the amount of latex production and the rubber plants life duration. The low amount of rubber production will lead to a low number of sales, so it will have an impact on the low revenue of rubber farmers. The purpose of this study was to find out the impact of the application of spiral tapping techniques on rubber crops toward farmer. The results showed that simultaneously the independent variables had a Significant effect on the Farmer revenues. Partially, rubber production and rubber prices had showed a significant effect on farmer’s revenues, while the age of crops and tapping techniques, had no significant effect on the farmer’s revenues. Although the variables of tapping techniques did not significantly effect to the farmer revenue but it gave the higher revenue than the other tapping techniques.

Lethal and sub-lethal toxicity of Verticillium lecanii on the biology of Mealybug (Pseudococcidae; Homoptera) under laboratory conditions

The Mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae) is a polyphagous pest of Citrus, grapevine, coffee and ornamental plants. The entomopathogenic fungus Beauveria bassiana, Metarhizium anisopliae, Verticillium lecanii and Isaria fumosorosea are very effective and commonly used as a biopesticide against various insect pests of different crops. The present study was conducted to check the lethal and sub-lethal effects of V. lecanii on mortality and life period of adult mealybug. Firstly LC50 value for nymph and adult was calculated by applying four different concentrations 1×105 , 1×106 , 1×107 and 1×108 CFU/ml. For nymphs, the median lethal concentration was 5.57×106 CFU/ ml, and for adults, 2.66×107 CFU/ml. After this, two lethal, 3.99×107 and 2.66×107 CFU/ml, and two sub-lethal concentrations, 1.33×107 and 6.65×106 CFU/ml, was prepared and tested against adult mealybug. Dose-dependent mortality was observed, and the highest mortality was due to the highest concentration of V. lecanii. The percentage mortality was 72.23, 52.78, 27.78 and 19.45% due to 3.99×107 , 2.66×107 , 1.33×107 and 6.65×106 CFU/ml, respectively, after 10 days of application. The weight of adult females was highest in the control treatment while lowest in high concentration, and it was gradually decreased after every day in the first three concentrations. The fecundity of mealybug also had an inverse relation with concentrations of V. lecanii, and the numbers of eggs were more in the control treatment than the other four treatments. The fecundity in lethal concentrations was reduced after the 8 th day of application. The life duration was most extended due to control treatment, 27 days, while the lowest period was due to the highest concentration, 13 days. Keywords: Verticillium lecanii, mealybug, mortality, weight, fecundity, life duration

Fuzzy mamdani logic inference model in the loading of distribution substation transformer SCADA system

<span id="docs-internal-guid-152e332e-7fff-7073-a541-1d420decb47b"><span>The research objective of supervisory control and data acquisition (SCADA), with fuzzy Mamdani logic simulation on the loading section of distribution transformer substations. Data acquisition is available when saving SAIFI SAIDI data and storing the results of monitoring equipment. The method used is Mamdani fuzzy logic, there are two input variables, namely current and voltage devices. The membership function in Mamdani fuzzy logic has been created based on the input current and voltage variables. Currently: parameter {0, 600} low is created {0, 350, 450, 600}, normal {400-650} parameter is created {400, 500, 550, 650}, parameter high {≥600} is created {600, 650, 750, 1000}, when determining the voltage: low {≤10.5} parameters {0 4 7 10.5}, normal {9-14} parameters {9, 10, 13, 14} and high {≥13} - parameters {13, 14, 15, 16}. Based on the results of the Mamdani logic rule test on the output current containing a transformer and a voltage sensor, the results obtained are IF (normal current; (630) AND voltage (high); (13.2) (high load transformer). The components in the simulation tool include miniature substations made with the 1A travel substation model, 3A substation as the main substation, the relay as distribution substation as the monitoring application. Telestatus and Telecontrol use a microcontroller. Initial scenario. After substation is resumed, data is stored after downtime, service life, duration, and data period. Initial scenario After substation is resumed, data is stored after downtime, service life, duration, and data period.</span></span>

The survival rate of tuberculosis patients in HIV-treated cohort of 2008-2018 in Almaty, Kazakhstan

Introduction: HIV/TB comorbidity is responsible for 1.6 million deaths worldwide. HIV/TB control and patients’ survival are still among priorities of the national HIV and TB programs. We aimed to evaluate the HIV/TB survival in connection with TB treatment outcomes and factors influencing life duration of the cohort 2008-2018 in Almaty, Kazakhstan. Methodology: This retrospective cohort study extracted data for all HIV and pulmonary TB adults coinfected during 2008-2018 in Almaty from national registries to apply descriptive, Kaplan-Meier estimation, and Cox proportional hazards regression model. Survival function for the TB treatment outcomes and factors predicting the probability of survival were tested and described. Results: The cohort population (n = 521) mean age was 37.4 years with 405 (77.7%) males and 210 (40.3%) marrieds. More than one TB treatment had 181 (34.7%) patients, 291 (55.9%) were smear-positive (SS+), and 423 (81.2%) were on antiretroviral therapy with mean CD4 count 254.22cells/µL. Probability to live longer was higher (128 versus 37 months, p = 0.003; 95% confidence interval (CI) 71.65, 184.35) for those who succeeded in TB treatment compared to “lost to follow-up” and “failed” treatment outcomes. Adjusted Cox regression model death hazard showed association with missing ART treatment (HR: 1.699, 95%CI 1.164, 2.481, p = 0.006) and having CD4 count < 499 (HR 2.398, 95%CI 1.191, 4.830, p < 0.014). Conclusion: TB treatment outcomes, ART treatment, and the CD4 count of HIV/TB coinfected population substantially influence their life duration. The medical decision- and policy-makers should take this into consideration when implementing targeted improvements in the national HIV and TB programs.

Goalkeepers Live Longer than Field Players: A Retrospective Cohort Analysis Based on World-Class Football Players

The purpose of this article is to study whether the position occupied by footballers on the pitch influences their life duration. It is known that various types of sporting activity (endurance, resistance, or mixed) may influence lifespan in different ways. However, there is a paucity of data regarding the role of different positions played in team sports such as football. Our research was based on elite international football players born before 1923 who took part in the first three football World Cups (n = 443) or played in the 1946/1947 season in the leading clubs of the main European leagues (n = 280). Goalkeepers were characterized by a 5–8-year longer life duration compared to their colleagues playing in other positions (World Cup: 82.0 ± 7.0 vs. 74.0 ± 8.0, p = 0.0047; European leagues: 83.0 ± 7.5 vs. 78.0 ± 8.0, p = 0.0023), with an absence of differences between defenders, midfielders, and forwards. Moreover, in both of the analyzed subgroups, the rate of survival until the 85th birthday was significantly higher among goalkeepers than among field players (p = 0.0102 and p = 0.0048, for both studied groups, respectively).

Browning of Early and Late-Harvested ‘Empire’ Apples Affected by Cold Storage and 1-MCP

The effects of harvest time, 1-methylcyclopropene (1-MCP) and air storage time on the susceptibility of flesh browning in ‘Empire’ apples were studied during a seven-day shelf life period after air storage at 0.5 °C for seven months. Early- or late-harvested ‘Empire’ apples without 1-MCP increased production of ethylene, respiration rates and internal ethylene concentration during the shelf life. Respiration rates increased in the late-harvested fruit for the shelf life period with/without 1-MCP treatment. The 1-MCP-treated fruit was approximately 10 N firmer than fruit not treated with 1-MCP at an early harvest for the entire shelf life duration. Peroxidase activity and percent change in electrical conductivity in the flesh were elevated in late-harvested fruit for the shelf life duration, whereas polyphenol oxidase activities were found to be stimulated by 1-MCP treatment, regardless of harvest time. Late-harvested fruit treated with 1-MCP exhibited increased susceptibility to flesh browning during shelf life, mostly due to reduction of the antioxidant defense mechanism of the fruits to stress in extending storage life, increasing polyphenol oxidase (PPO) activity and electrolyte leakage rate.