The Specific Length of an Underground Tunnel and the Effects of Rock Block Characteristics on the Inflow Rate

The specific length of a tunnel (STL) and a new analytical model for calculating the block surface area of the rock mass are introduced. First, a method for determining the appropriate length of a tunnel for a numerical simulation is described. The length is then used to examine the correlation between the inflow rate to the tunnel and the block volume, the block surface area, and the fracture intensity (P32) through analytical and numerical modeling. The results indicate that the length of the tunnel should at least be equal to the least common multiple (LCM) of the apparent spacings of the joint sets at the wall of the tunnel to obtain the more reliable and immediate results for the inflow rate to a tunnel that is excavated in a fractured rock mass. A new analytical model was developed to calculate the block surface area and determine the essential joint set parameters, which include the dip, dip direction, and spacing. The determination of the rock block characteristics through numerical modeling requires considering the intact block for calculations. The results indicated that the inflow rate to the tunnel increased with an increase in fracture intensity and a decrease in block volume and surface area. The STL and the analytical model used for calculating the block surface area are validated through numerical simulations with 3DEC software version 7.0.

Water Level Monitoring and Dam Valve Control over IOT

This project gives an outline for the development of an information system based on the existing systems with the utilization of some sensors and IOT. The cradle of this project is based on methodology of IOT. Water level in a dam needs to be maintained effectively to avoid complications. The quantity of water released is hardly ever correct resulting in wastage of water and it is impossible for a man to precisely control the gates without knowledge of exact water level and water inflow rate. We have developed a mechatronics based system. We have designed a system in which real time things are interconnected to web. Water level contactless Ultrasonic sensor is placed in tub connected through Arduino UNO to serve the same purpose automatically and forward the status to it. This system detects the level of water and estimate the water inflow rate in a tub and thereby control the Solenoid valve using IOT in a real-time basis. The water level is analysed using this sensor and updated in the web server using IOT module connected to the Arduino UNO. Arduino unit checks that input and upload the status of water level on web. Keywords: IOT (Internet of Things), Mechatronics, Ultrasonic sensor, Arduino UNO, Solenoid valve.

Predicting Inflow Rate of the Soyang River Dam Using Deep Learning Techniques

The Soyang Dam, the largest multipurpose dam in Korea, faces water resource management challenges due to global warming. Global warming increases the duration and frequency of days with high temperatures and extreme precipitation events. Therefore, it is crucial to accurately predict the inflow rate for water resource management because it helps plan for flood, drought, and power generation in the Seoul metropolitan area. However, the lack of hydrological data for the Soyang River Dam causes a physical-based model to predict the inflow rate inaccurately. This study uses nearly 15 years of meteorological, dam, and weather warning data to overcome the lack of hydrological data and predict the inflow rate over two days. In addition, a sequence-to-sequence (Seq2Seq) mechanism combined with a bidirectional long short-term memory (LSTM) is developed to predict the inflow rate. The proposed model exhibits state-of-the-art prediction accuracy with root mean square error (RMSE) of 44.17 m3/s and 58.59 m3/s, mean absolute error (MAE) of 14.94 m3/s and 17.11 m3/s, and Nash–Sutcliffe efficiency (NSE) of 0.96 and 0.94, for forecasting first and second day, respectively.

Investigating the effect of different slip zone locations on the lubrication performance of textured journal bearings

Purpose This study aims to purpose the suitable location of slip boundary condition and microscale surface textures to enhance the tribological performance of the hydrodynamic journal bearings. Design/methodology/approach Mass conserving Elrod cavitation algorithm with considering slip boundary condition has been used for predicting the static performance characteristics (load carrying capacity, coefficient of friction and volumetric inflow rate) of finite cylindrical shape textured journal bearings. Findings It has been observed that the full textured bearing with slip boundary condition in between 0°–180° circumferential region gives a significant reduction in the lubricant rupture zone. However, the introduction of textures up to the interface of slip and the no-slip region is increasing the load-carrying capacity and reduces the shear stress. This reduction in shear stress with combined slip and surface textures is effective in increasing the volumetric inflow rate of the lubricant. Practical implications The combined effect of slip boundary condition and surface texturing is increasing the scope of liquid lubricants in hydrodynamic journal bearings and further contributing toward the development of small-scale rotating machines. Originality/value The study related to the use of mass conserving Elrod cavitation algorithm for finding the optimum location of slip and surface texture zones has been found rare in the literature. Previous studies show that the mass conserving Elrod cavitation algorithm gives realistic results for textured bearings and its findings show good agreement with the experimental observations.

Produksi Bersih Pengolahan Limbah Cair Menggunakan Decanter pada PT Aetra Air Jakarta

ABSTRACT Clean water process production by PT Aetra Air Jakarta (AAJ) emits a lot of wastewater. All this time, a sludge drying bed is used for its production activities, where the sludge produced is not proportional to the area and length of drying time, so the unsatisfied sludge is eventually dumped into the water body. In line with the need to improve the quality of operational activities, clean water service providers are trying to create zero waste. They are environmentally friendly through the use of a decanter. The research objective was to determine the amount of sludge treated in the wastewater treatment process and measure water removal efficiency in sludge using a decanter. Methods of data collection through observation and testing of wastewater treatment using a decanter. The decanter treatment process starts from taking the sludge sample before it is processed; the sludge treatment process begins entering the decanter until the sludge is finished processing. The results showed that the average volume of sludge was 24.84 m3, and the water removal efficiency was between 89–91%. The conclusion is that the set inflow rate is directly proportional to TSS while the efficiency of TSS water removal in the sludge is smaller so that the use of a decanter is greater. It recommended that the residual processing sludge be used as raw material for fertilizer production. The Pb and Zn content in the sludge does not exceed the quality standard. Keywords: decanter, clean production, TSS, sludge volume ABSTRAK Air bersih yang diproduksi oleh PT Aetra Air Jakarta (AAJ) mengeluarkan banyak limbah cair. Selama ini, kegiatan produksinya digunakan sludge drying bed, dimana lumpur yang dihasilkan tidak sebanding dengan luas dan lamanya waktu pengeringan, sehingga lumpur yang tidak tertampung akhirnya terbuang ke badan air. Seiring kebutuhan perbaikan kualitas kegiatan operasional, penyedia layanan air bersih berupaya menciptakan zero waste dan ramah lingkungan melalui penggunaan decanter. Tujuan penelitian menentukan jumlah lumpur yang diolah pada proses pengolahan limbah cair dan mengukur efisiensi penyisihan air pada limbah lumpur menggunakan alat decanter. Metode pengumpulan data melalui pengamatan dan pengujian pengolahan limbah cair menggunakan decanter. Proses pengolahan decanter dimulai dari pengambilan sampel lumpur sebelum diolah, proses pengolahan lumpur dari awal masuk ke decanter sampai lumpur selesai diolah. Hasil penelitian menunjukkan rata-rata volume lumpur sebesar 24,84 m3, dan efisiensi penyisihan air antara 89–91%. Kesimpulannya adalah set inflow rate berbanding lurus dengan TSS sedangkan efisiensi penyisihan air TSS pada limbah lumpur semakin kecil sehingga penggunaan decanter menjadi lebih besar. Direkomendasikan agar lumpur sisa pengolahan dimanfaatkan sebagai bahan baku untuk pembuatan pupuk dengan syarat kandungan Pb dan Zn dalam lumpur tidak melebihi baku mutu. Kata kunci: decanter, produksi bersih, TSS, volume lumpur

Enhancement of water productivity with surge irrigation

Surge irrigation is the intermittent application of water to surface irrigated furrows or borders in a series of relatively short on and off time periods during the irrigation which may be between 20 minutes to two hours. In this technique, water is usually applied intermittently rather than with a continuous stream, as in conventional surface irrigation..Water productivity and water saving of six crops viz. wheat, cotton, maize, capsicum, onion and fennel under surge irrigation were compared with traditional method for the crops grown in different environmental conditions at different location of the world.It is concluded that surge flow irrigation performs better than continuous flow irrigation in terms of water saving and yield resulting in enhancement of water productivity. In case of wheat crop, surge irrigation saved and decreased irrigation water by 27, 33.4 and 37.4 % and increased yield by 15.1, 17.7 and 12.7 % under slope of 0.0, 0.1 and 0.2 % respectively compared with continuous flow irrigation for the same discharge. It had the maximum water use efficiency values of 1.39, 1.56 and 1.59 kg/m3 for surge flow irrigation under slopes of 0.0, 0.1 and 0.2 %, respectively.Surge irrigation system for maize obtained the highest value of WUE (1.63 kg/m3) with 40 m furrow length under 12.24 l/min inflow rate, while the lowest value of WUE obtained by continuous irrigation system, with 20 m furrow length under 44.4 l/min inflow rate (1.05 kg/m3). It can be applied by farmers in areas where irrigation water is limiting factor in crop production and farmers cannot afford costly micro-irrigation system.

Forensic Investigation of Four Monitored Green Infrastructure Inlets

Green infrastructure (GI) is viewed as a sustainable approach to stormwater management that is being rapidly implemented, outpacing the ability of researchers to compare the effectiveness of alternate design configurations. This paper investigated inflow data collected at four GI inlets. The performance of these four GI inlets, all of which were engineered with the same inlet lengths and shapes, was evaluated through field monitoring. A forensic interpretation of the observed inlet performance was conducted using conclusions regarding the role of inlet clogging and inflow rate as described in the previously published work. The mean inlet efficiency (meanPE), which represents the percentage of tributary area runoff that enters the inlet was 65% for the Nashville inlet, while at Happyland the NW inlet averaged 30%, the SW inlet 25%, and the SE inlet 10%, considering all recorded events during the monitoring periods. The analysis suggests that inlet clogging was the main reason for lower inlet efficiency at the SW and NW inlets, while for the SE inlet, performance was compromised by a reverse cross slope of the street. Spatial variability of rainfall, measurement uncertainty, uncertain tributary catchment area, and inlet depression characteristics are also correlated with inlet PE. The research suggests that placement of monitoring sensors should consider low flow conditions and a strategy to measure them. Additional research on the role of various maintenance protocols in inlet hydraulics is recommended.

Morphological and Kinematical Analysis of the Double-barred Galaxy NGC 3504 Using ALMA CO (2–1) Data

We present results obtained from ALMA CO (2–1) data of the double-barred galaxy NGC 3504. With three times higher angular resolution (∼ 0.″8) than previous studies, our observations reveal an inner molecular gas bar, a nuclear ring, and four inner spiral arm-like structures in the central 1 kpc region. Furthermore, the CO emission is clearly aligned with the two dust lanes in the outer bar region, with differences in shape and intensity between them. The total molecular gas mass in the observed region (50″ × 57″) is estimated to be ∼3.1 × 109 M⊙, which is 17 per cent of the stellar mass. We used the Kinemetry package to fit the velocity field and found that circular motion strongly dominates at R = 0.3 − 0.8 kpc, but radial motion becomes important at R < 0.3 kpc and R = 1.0 − 2.5 kpc, which is expected due to the presence of the inner and outer bars. Finally, assuming that the gas moves along the dust lanes in the bar rotating frame, we derived the pattern speed of the outer bar to be 18 ± 5 km s−1 kpc−1, the average streaming velocities on each of the two dust lanes to be 165 and 221 km s−1, and the total mass inflow rate along the dust lanes to be 12 M⊙ yr−1. Our results give a new example of an inner gas bar within a gas-rich double-barred galaxy and suggest that the formation of double-barred galaxies could be associated with the existence of such gas structures.

Effects of Different Inflow Rate Patterns and Distributions of Grass Strips on Runoff and Sediment in an Engineering Accumulation Body

Engineering accumulation bodies are critical sources of artificial soil and water loss. The objectives of this study were to evaluate the effects of different inflow rate patterns and distributions of grass strips on runoff and sediment in engineering accumulation bodies. A field runoff plot (20 m long, 1 m wide, and 0.5 m deep) was used for inflow simulation experiments under four inflow rate patterns (even, rising, falling, and rising-falling) and five grass strip patterns (patterns Ⅰ-Ⅴ). The results showed that the changing trends of runoff rate and sediment yield increased with increasing inflow rate and decreased with reduction for the same grass strip pattern. Although the inflow rate pattern affected runoff and sediment yield, it had no significant effect on the total runoff and sediment. The influence of the grass strip pattern on runoff and sediment was significantly higher than that of the inflow rate pattern. The runoff reduction and sediment reduction effects of grass strip patterns were 12.23 to 49.62% and 12.92 to 80.54%, respectively. When grass strips were distributed on a slope in bands (pattern Ⅴ), the soil and water conservation effects were ideal, reducing the average runoff and sediment by 44.98% and 58.09%, respectively. Sediment reduction caused by decreasing runoff (SRR) was the main factor controlling erosion and sediment yield. This study can guide the configuration of vegetation control measures for soil and water loss in engineering accumulation bodies.