Analysis of Water Quality Characteristics in Unit Watersheds in the Hangang Basin with Respect to TMDL Implementation

Spatiotemporal water quality tendencies before and after total maximum daily load (TMDL) implementation in the Hangang basin were analyzed to determine the water quality improvement resulting from the TMDL policy. The periodicities of water quality indicators were also analyzed and water quality characteristics corresponding to different unit watershed units were identified in terms of pollution source. Considering five water quality indicators, including biochemical oxygen demand and total phosphorus, it was observed that water quality indicator concentrations were low in the upstream areas of the Bukhangang and Namhangang watersheds. However, they were high between the downstream areas of the Namhangang watershed and the Imjingang watershed and in the Hangang downstream and Jinwicheon watersheds. Additionally, the concentrations of water quality indicators in most of the unit watersheds where TMDL had been implemented decreased after TMDL implementation. However, increasing tendencies in the concentrations of water quality indicators continued to be observed in some of the watershed units in the upstream areas of the Bukhangang and Namhangang watersheds, possibly because these watersheds are affected by nonpoint source pollution owing to rainfall. Therefore, in the future, it would be necessary to implement policies that take these findings into consideration.

Bootstrapping the Boundary between Research and Environmental Management: The TMDL as a Point of Engagement between Science and Governance

Knowledge produced by environmental scientists is often inaccessible, intractable, or otherwise in need of reconfiguration for use in environmental regulation. Similarly, policy knowledge undergoes decontextualization in its address to the community of researchers and data curators whose findings are fundamental to its operation. This paper addresses the development of the total maximum daily load (TMDL) measurement as a means of decontextualizing both scientific and regulatory processes to render the practical results of those processes available as a means of collaboration, coordination, and development of watershed management and regulation. The TMDL measurement serves as a specific type of boundary object, a provisional boundary figure. A provisional boundary figure is a complex, model-derived system that is not fixed but rather an object of ongoing work that enables coordination between policy and research. Thus, the TMDL is deployed to explore the relationship between environmental management and the knowledge workers that enable and support it.

Analysis of the Carrying Capacity and the Total Maximum Daily Loads of the Karang Mumus Sub-watershed in Samarinda City Using the WASP Method

Watershed is a multi-aspect ecological system, which functions as a source of water resources, in order to meet daily needs. It also motivates both economical and life matters, as well as serve as a sanitary channel for the surrounding community. Watershed also generates pollutants, which are known to potentially cause a decrease in river water quality. The degradation of river habitats that are caused by high pollutants penetration into the water body, decreases the capacity to carry out self-purification of toxic loads. The water pollutant load-carrying capacity is then calculated through various methods, one of which is the use of a computerized numerical modeling simulation called WASP (Water Quality Analysis Simulation Program). This method was developed by the ES-EPA, in order to process TMDLs (Total Maximum Daily Loads) data on river bodies, as well as examine each part of the water quality, based on spatial and temporal inputs. This study was conducted at the Karang Mumus Sub-watershed flowing through the centre of Samarinda City, with aims to determine the pollutants' carrying capacity, existing load, and toxic waste allocation, via the use of the BOD (Biological Oxygen Demand) technique as a parameter of water quality. The calculation was carried out by segmenting the river into five parts, based on the number of districts it passes through, during pollutant loads inventory. The WASP modeling simulation showed that the total pollutant load-carrying capacity of the whole segments was 5,670 kg/day. It also showed the existing loads of about 3,605 kg/day, with the margin having the ability to receive pollutants at 2,065 kg/day. Moreover, the allocation of pollutant loads varies for each segment, with 2, 3, and 4 observed to reduce the pollutant by 390, 220, and 10 kg/day, respectively. However, segments 1 and 5 were still allowed to receive pollutant loads up to 1,740 and 945 kg/day, respectively.

Radiological urban threat due to special protective actions from security forces

The neutralization of suspicious objects by a conventional explosion in public places seems to be an option often considered by security forces. A radiological dispersive device (RDD) uses a radioactive material coupled to an amount of conventional explosive in order to contaminate an area. Extremist groups may take advantage of such protocol by leaving the radioactive material in public places to provoke suspicion, thus leading to the neutralization by an explosion, which in turn creates a RDD event. This work aims to discuss the influence of such a protocol in the radiological threat by means of computational simulation. The total maximum effective dose equivalent (TEDE Max), the Pasquill–Gifford atmospheric stability classes (PG classes), and the potentially affected population size were evaluated. The results consider two radionuclides Cs-137 and Sr-90. The findings allow us to infer that TEDE Max and surface contamination are strongly dependent on the PG classes. In addition, the affected population size depends on the plume size, which seems to be independent of the radionuclide, but not of the PG classes. Therefore, PG classes play a key role in the radiological threat. The findings may be of value to support decisions when facing an event.

Analisis Tingkat Kreativitas Wirausaha Mahasiswa Melalui Program Komunitas Entrepreneur

This research is motivated by the Entrepreneur Community Program's existence as support for entrepreneurship courses in the Islamic Banking Department, Faculty of Economics, UIN Maulana Malik Ibrahim Malang to produce graduates who have high selling value, entrepreneurship, and creativity to be able to compete. The learning approach in the program is Project-Based Learning. This study aimed to analyze the level of student creativity before and after participating in the Entrepreneur Community Program. The number of participants was 75 students from the concentration of entrepreneurs in the observation year. Data analysis used nonparametric statistics with Paired-Samples T-Test in testing the creativity of the respondent level before and after treatment and assessing the creativity level of students based on the results of the creativity score generated from the total score filled by respondents divided by the total maximum score of each statement and outlined in the form proportion. The breakthrough research results showed that there were differences in the level of students before and after treatment. The treatment here means that students take part in the entrepreneurial community program with Project-Based Learning. They increased student creativity from 70% to 83%. The level of student creativity before treatment was in the medium category. Moreover, after getting the treatment is in the high category. Thus, project-based learning through the Entrepreneur Community Program in Islamic Banking Department, Faculty of Economics can increase student entrepreneurial creativity.

Power dissipation analysis of PV module under partial shading

Photovoltaic (PV) generation has been growing dramatically over the last years and it ranges from small, rooftop-mounted or building integrated systems, to large utility scale power stations. Especially for rooftop-mounted PV system, PV modules are serially connected to match with PV inverter input voltage specification. For serially connected PV system, shading is a problem since the shaded PV module reduces the output whole string of PV modules. The excess power from the unshaded PV module is dissipated in the shaded PV module. In this paper, power dissipation of PV module under partial shading is analyzed with circuit analysis for series connected PV modules. The specific current and voltage operating point of the shaded PV module are analyzed under shading. PSIM simulation tool is used to verify the power dissipation analysis. When there is no bypass diode and three solar modules are connected in series, upto 39.1% of the total maximum PV power is dissipated in the shaded PV module. On the other hand, when the bypass is attached, 0.3% of the total maximum power is generated as a loss in the shaded PV module. The proposed analysis technique of shaded PV module could be used in PV system performance analysis, especially for maximum power point tracking (MPPT) performance.

Lower drive of continuous action unit to form underlying layer of road

Introduction. A continuous action unit for the formation of an underlying layer is designed to increase productivity in the construction of roads and other facilities, for which it is necessary to remove the top layer of soil. In the bucket of the continuous action unit to form an underlying layer of roads provides the use of working bodies, cutting the ground with blades of knives. The cut-off soil enters the buckets. The forces attached to the bucket are considered. Theoretically reasonable total energy costs for ground cutting of one cubic meter by buckets of continuous action unit to form an underlying layer of roads requires 109 kilojoules. Based on the calculations carried out, it is possible to determine the torque, the power required for the lower drive, the transmission ratio from the hydraulic motor to the stars, to develop the design of many elements of the continuous action unit to form the underlying layer of the road.The method of research. To determine the torque, the power required for the lower drive, the transmission ratio from the hydraulic motor to the asterisks, to the projection of the bucket on the horizontal plane attached all forces are applied directed along the bucket. As a result of their addition, the total maximum traction force of moving all the boilers during their filling with soil was revealed. On the basis of this, the method of calculating the parameters of the required is given. There is a danger of the ground being poured out of the bucket when it is rotated on the leading stars of the lower drive. To check the parameters received, the bucket is rotated by 90 degrees on the leading stars of the lower drive. The forces acting on the ground, located in the bucket, at the moment of the beginning of the turn of the bucket were revealed. A system of equations has been created, on the basis of which the condition of inadmissibility of the dumping of soil from the bucket at its turn on the leading stars has been established.Results. As a result of the addition of forces directed in the course of the bucket, the total maximum traction force of moving all the boilers during their filling with the ground, traction force on the right chain and left chain is defined. Traction chains are chosen by destructive load. The torque of the lower drive, the angular speed of the drive stars, the power required for the lower drive, the transmission ratio from the hydraulic motor to the asterisk are calculated. Based on the transferable power, a gerotor motor is chosen for the lower drive of the unit. On the basis of the calculations the design of chains, support rink, chain suspension have been developed.Conclusion. Based on the calculations made, the maximum traction force of all the buckets during the period when they are filled with soil is 11,870 newtons, the torque of the lower drive is 2,362 newtonometers, the speed of the chains is 1,686 meters per second, the angular velocity of the drive stars is 8,47 radians per second, power required for lower drive is 20 kilowatts. Based on the transferable power, it is advisable to use MT-160 gerotor motor and a single-stage planetary gearbox with a transmission ratio from the hydraulic motor to the stars 7,674. The calculations made it possible to develop the design of many elements of the continuous action unit to form an underlying layer of roads.

Coulomb stress analysis for several filling and operational scenarios at the Grand Ethiopian Renaissance Dam impoundment

Increased demand for power generation coupled with changing seasonal water uncertainty has caused a worldwide increase in the construction of large hydrologic engineering structures. That said, the soon-to-be-completed Grand Ethiopian Renaissance Dam (GERD) will impound the Blue Nile River in Western Ethiopia and its reservoir will encompass ~ 1763 km2 and store ~ 67 Gt (km3) of surface water. The impoundment will undergo maximum seasonal load changes of ~ 28 to ~ 36 Gt during projected seasonal hydroelectric operations. The GERD impoundment will cause significant subsurficial stresses, and could possibly trigger seismicity in the region. This study examines Coulomb stress and hydrologic load centroid movements for several GERD impoundment and operational scenarios. The maximum subsurficial Coulomb stress applied on optimally oriented fault planes from the full impoundment is ~ 186 kPa and over 30% of our model domain incurs Coulomb stresses ≥ 10 kPa, regardless of the impoundment period length. The main driver behind Coulomb stress and load centroid motion during impoundment is the annual, accumulated daily reservoir storage change. The maximum Coulomb stresses from the highest amplitude season of five long-term operational scenarios are around 36, 33, 29, 41, and 24% of the total maximum stresses from the entire GERD impoundment. Variations in annual Coulomb stresses during modeled GERD operations are attributed to the seasonal load per unit area, and partially to the initial seasonal water level. The spatial patterns and amplitudes of these stress tensors are closely linked to both the size and timing of GERD inflow/outflow rates, and an improved understanding of the magnitude and extent of these stresses provides useful information to water managers to better understand potential reservoir triggered seismic events from several different operational and impoundment strategies.