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Knowing the characteristics of wastewater and its interaction with the channel is crucial to finding a suitable model and maintenance method to solve the closed channel problem. The purpose of this study is to find the relationship and how much it influences the characteristics of wastewater in closed channels and analyze the limit deposit velocity (LDV) of wastewater so that there is no deposition. The parameters used to analyze wastewater characteristics are density, oil and fat, specific gravity, total suspended solids, total dissolved solids, and kinematic viscosity. The parameters used to analyze the flow characteristics in closed channels are velocity, discharge, Reynolds number, friction coefficient, energy loss, and hydraulic gradient. The method used is experimental research by simulating a closed-channel model prototype. The closed channel model is made from an acrylic pipe with a length of 6 m and a pipe diameter of 0.064 m. Simulations on each wastewater sample and the discharge variations used were 0.005, 0.004, 0.003, and 0.0015 m3/s. Velocity measurements at a 0.5 pipe water level height and distances of 0, 2, 4, and 6 m. The results showed that the nature and composition of the wastewater the flow velocity. The large value of wastewater parameters shows that the flow velocity is small. The wastewater content is considered a load that must be transported to the end of the closed channel. When the discharge increases, the velocity will increase, Reynolds number will increase, and the energy loss will be large, while the friction coefficient is inversely proportional to Reynolds number. The velocities of clean water samples are 2.90 - 1.07 m/s, tofu - making is 2.83 - 1.07 m/s, household is 2.74 - 0.85 m/s, laundry is 2.84 - 1.03 m/s, and the workshop is 2.54 - 0.66 m/s. The limit deposit velocity (LDV) for household wastewater is 1.49 m/s to prevent deposition in closed channels. Doi: 10.28991/CEJ-2023-09-01-03 Full Text: PDF

Improvement of hollow brick models demands profound analysis in terms of their behavior on mechanical properties as some shape variations provide different characteristics on stress concentration. Additional waste filler i.e. sago husk and utilization of bottom ash are expected to deliver better results based on strength, weight and economic factor. This paper aims to analyze experimentally and analytically those 7 shapes variations of modified hollow bricks design with additional admixtures which consists 1,1% of sago husk and 4 composition of bottom ash i.e. 0%; 10%; 20%; and 25%. Some works were conducted in laboratory, and followed by mathematical stress analysis of hollow shape characteristics. The results show that 10 – 20% bottom ash composition share maximum value of compressive strength, with model 1 is the greatest (17.8 Mpa). Mathematical analysis provides similar results as well, where the stress concentration of model 1 was not amplified with subsequent hollow position. In conclusion, all model still appropriate to be utilized for housing, especially in element selection for lightweight bricks that meet the requirements for strength.

Leprosy, also known as Hansen’s disease, is caused by the bacterium Mycobacterium leprae. This disease attacks the skin, peripheral nerves, upper respiratory tract mucosa and eyes. This bacterium undergoes a long division process between 2-3 weeks. The survival of leprosy bacteria is 9 days outside the human body. Leprosy germs have an incubation period of 2-5 years. The World Health Organization reported that in 2019, 202,256 new cases of leprosy were detected in 118 countries, and that 79% of these were in India and Brazil. This study obtained data on leprosy from the Kendari City Health Office for 2017 to 2020. According to the findings, in 2018, the prevalence of leprosy in Kendari was 0.73%. The span was found to be 15 years with multi-bacillary type/wet leprosy with level 0 defects. Males were found to be the most susceptible to infection. There was a decrease in 2020 in the number of new cases of leprosy. Keywords: leprosy, Southeast Sulawesi, Indonesia