Power Distribution Planning Reference Book (Power Engineering, Vol 1)
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It presents an integrated look at the three largest changes affecting distribution planners, and how they can deal with their combined impact. These changes are the increasing emphasis on reliability and achieving reliability targets, an increasingly business-basis in all spending and resource decisions, and far less emphasis on long-range system planning.
Reliability is important because in the 21st century it has become and will remain an explicitly measured and tracked aspect of utility performance, something the utility and its planners must engineer and manage well. The increasing business basis is due to a host of factors discussed in various parts of this book, but its net impact on planners is to change the context within which their recommendations are made: modern utilities make all spending decisions on a business-case basis.
The shift to more short-range and less long-range focus is not, as often thought, due to a narrow "profit now" business focus by utilities. Instead, it reflects a shift in the importance of both engineering and business considerations. The higher utilization ratios and the greater emphasis on reliability faced by modern utilities mean that planning mistakes are more costly and may take longer to fix. Chapter 26 begins by looking at the distribution planning process itself.
Despite all the changes, the core of the planning process is much as it always was, even if the metrics used and context within which it works have changed dramatically. Planning still involves setting goals, identifying and evaluating options, and selecting the best option. Each of these planning steps is examined in detail, along with its common pitfalls. Short- and longrange planning are defined and their different purposes and procedures studied.
Chapter 27 looks at how the forecasting tools covered in Chapter 25 are used, and how planners organize themselves and their forecast-translated-to-capability-need methodology so that they can efficiently accommodate their company's requirements. In a modern highutilization ratio, just-in-time utility, correctly anticipating future needs could be said to be the critical part of planning. Fully half of all recent large-scale outages and blackouts have been due, at least in part, to deficiencies that started with poor recognition or anticipation of future system capability needs.
Chapter 28 looks at balancing reliability against spending. Many power engineers buying this book will consider this its key chapter. It presents the basics of reliability-based distribution planning including processes and procedures aimed at achieving specific reliability targets. But at most electric delivery utilities there is more involved than just a reliability-based approach and an explicit focus on attaining reliability targets.
To be successful, reliability-based planning must be interfaced into the "business" framework of an electric utility. When successfully integrated into a utility's investment, system, and operational planning functions, this is often called asset Copyright by Marcel Dekker, Inc. Since these concepts are new, and represent a considerable step change to most utilities, the chapter also includes a simple but effective "cookbook" on CERI CostEffective Reliability Improvement projects used to bootstrap a utility's move toward explicit cost- or spending-based management of reliability.
Chapter 29 is a considerable departure from previous chapters and sure to be somewhat controversial and discomforting to some planners. It discusses objectivity and accuracy in distribution planning, frankly and explicitly addressing the fact that some planning studies are deliberately biased in both their analysis and their reporting, so that they do not present a truly balanced representation and comparison of alternatives based on their merits.
As shown, there is a legitimate, and in fact critical, need for such reports in the power industry, and there is nothing unethical about a planning study that declares its intent to "make a case" for a particular option with an advantageous set of assumptions and analysis. But the sad truth is that some planning studies contain hidden bias, because of unintended mistakes, or deliberate efforts to misrepresent a truthful evaluation.
Part of this chapter is a "tutorial on cheating" - giving rules and examples of how to disguise a very biased analysis so that it gives the appearance of objectivity and balance. This is then used to show how planners can review a report for both accuracy and objectivity, and how to detect both unintended mistakes as well as bias that has been carefully hidden.
Journal of Physics: Conference Series, Volume 1,, - IOPscience
Chapter 30 concludes with a summary and integrating perspective on the book's key points as well as a set of guidelines and recommendations for modern distribution planners. This book, along with a companion volume Spatial Electric Load Forecasting, Marcel Dekker, , took more than a decade to complete. Most of all, I wish to thank my wife, Lorrin Philipson, for the many hours of review and editorial work she unselfishly gave in support of this book, and for her constant, loving support, without which this book would never have been completed.
Power Delivery Systems 1. Consumer Demand and Electric Load 2. Electric Load, Coincidence, and Behavior 3. Power System Reliability 4. Economics and Evaluation of Cost 5. Evaluation, Prioritization, and Approval 6. Equipment Ratings, Loadings, Lifetime, and Failure 7. Equipment Failures and System Performance 8. Whether marketed by a local utility, load aggregator, or direct power retailer, this electric power must flow through a power delivery system on its way from power production to customer.
For those unfamiliar with power delivery, it provides an outline of the most important concepts. For this reason experienced planners are advised to scan this chapter, or at least its conclusions, so that they understand the perspective upon which the rest of the book builds. In a traditional electric system, power production is concentrated at only a few large, usually isolated, power stations.
In some cases, cost can be lowered and reliability enhanced through the use of distributed generation - numerous smaller generators placed at strategically selected points throughout the power system in proximity to the customers. This and other distributed resources - so named because they are distributed throughout the system in close proximity to customers - including storage systems and demand-side management, often provide great benefit.
These systems represent an investment of billions of dollars, require care and precision in their operation, and provide one of the most basic building blocks of our society - widely available, economical, and reliable energy. Section 1. The typical hierarchical system structure that results and the costs of its equipment are summarized in sections 1.
In section 1. The chapter ends with a look at the "systems approach" perhaps the single most important concept in the design of retail delivery systems which are both inexpensive and reliable. The system must deliver power to the customers, which means it must be dispersed throughout the utility service territory in rough proportion to customer locations and demand Figure 1.
That electrical path must be reliable, too, so that it provides an uninterrupted flow of stable power to the utility's customers. Reliable power delivery means delivering all of the power demanded, not just some of the power needed, and doing so all of the time. Anything less than near perfection in meeting this goal is considered unacceptable - Lines show major roads and highways.
Figure 1. Degree of shading indicates electric load distribution. Power Delivery Systems Table 1. Cover the utility's service territory, reaching all consumers who wish to be connected and purchase power. Have sufficient capability to meet the peak demands of those energy consumers. Provide satisfactory continuity of service reliability to the connected energy consumers. Provide stable voltage quality regardless of load level or conditions. Most electrical equipment in the United States is designed to operate properly when supplied with 60 cycle alternating current at between and volts, a plus or minus five percent range centered on the nominal utilization voltage of volts RMS average of the alternating voltage.
In many other countries, utilization standards vary from to slightly over volts, at either 50 or 60 cycles AC. A ten percent range of delivery voltage throughout a utility's service area may be acceptable, but a ten percent range of fluctuation in the voltage supplied to any one customer is not. An instantaneous shift of even three percent in voltage causes a perceptible, and to some people disturbing, flicker in electric lighting.
More important, voltage fluctuations can cause erratic and undesirable behavior of some electrical equipment. Thus, whether high or low within the allowed range, the delivery voltage of any one customer must be maintained at about the same level all the time - normally within a range of three to six percent - and any fluctuation must occur slowly. If this range of load fluctuation is too great, or if it happens too often, the customers may consider it poor service.
This provides volts of power to any appliance that needs it, but for purposes of distribution engineering and performance acts like only volt power. Industry studies of outages and interruptions during this period were almost entirely based around the "loss of revenue" that the utility would experience from poor reliability, and reliability was managed from that perspective.
To some extent, the view of utilities then was the same as a cable or broadcast TV network might have today: when we aren't distributing, we aren't earning. Just as a TV network knows that when its broadcast is interrupted its revenues from advertising are cut, so electric utilities in the first third of the 20th century knew that when equipment was out, they weren't earning money. Resources and actions to avoid outages were justified and managed from the standpoint that, to an extent, they were profitable because they kept the revenue stream coming into the utility's coffers.
During the s through the s, electric power came to be viewed as an essential and needed service, and reliability came to be viewed as an obligation the utility had to its customers. Most utilities, including their upper management, adopted a "public stewardship" attitude in which they viewed themselves and their company as having an obligation to maintain power flow to their customers.
However, the computer and data collection technologies needed to collect and manage quantitative data on customer-level reliability were not available at that time as they are today. A widespread outage overnight might be reported to management the next morning as "we had a lot of customers, maybe as many as 40,, out for quite a while, and had about sixteen crews on it all night. Several changes occurred during the period through that led to more quantitative emphasis on reliability.
First, electric power increasingly became "mission critical" to more and more businesses and homes. Equally important, it became possible to measure and track reliability of service in detail. Modern SCAD A, system monitoring, outage management, and customer information systems permit utilities to determine which customer is out of service, and when, and why. Reports see footnote 2, below can be prepared on individual outages and the reliability problems they cause, and on the aggregate performance of the whole system over any period of time. Managerial study of past performance, and problems, could be done in detail, "slicing and dicing" the data in any number of ways and studying it for root causes and improved ways of improving service.
Thus, the growing capability to quantitatively measure and study reliability of service enabled the industry to adopt much more specific and detailed managerial approaches to reliability. Simultaneously, during the s and s, first-world nations adopted increasing amounts of digital equipment. Similarly, digital systems became the staple of "efficient" manufacturing and processing industries, without which factories could not compete on the basis of cost or quality.
This dependence on digital systems raised the cost of short power interruptions. For example, into the mid s, utilities routinely performed switching transfer of groups of between and homes in the very early morning hours, using "cold switching"; a 2. By contrast, today management, and regulators, would receive a report more like "a series of weatherrelated events between and interrupted service to 36, customers, for an average of 3 hours and 12 minutes each, with 22, of them being out for more than four hours.
Seven crews responded to outage restoration and put in a total of hours restoring service. Fifteen corrective maintenance tickets for permanent completion of temporary repairs made to restore service remain to be completed as of 9 AM this morning. In most distribution systems, every distribution equipment outage causes service interruptions because there is only one electrical path to every consumer. Reliability measures are based on two characteristics: Frequency - how often power interruptions occur Duration - how long they last Equity of reliability - assuring that all customers receive nearly the same level of reliability - is often an important part of managing reliability performance.
Drops in voltage sags often have the same impact as complete cessation of power. Energy consumers who even noticed the events were rare; analog electric clocks would fall a few seconds behind, that was all. Like the clocks, devices in "pre-digital" homes would immediately take up service again when power was restored. But today, a similar "cold switching" event would disable digital clocks, computers, and electronic equipment throughout the house, leaving the homeowners to wake up often late because alarms have not gone off to a house full of blinking digital displays.
Surveys have shown homeowners consider even a "blink" interruption to cause them between seven and fifteen minutes of inconvenience, resetting clocks, etc.
Table of contents
To accommodate this need, utilities must use "hot switching" in which a switch to the new source is closed first, and the tie to the old source is opened. This avoids creating any service interruption, but can create operating problems by leading to circulating loop currents that occasionally overload equipment. This gradual change in the impact of brief interruptions has had even a more profound impact on business and industry than on homeowners. In the s, the outage of power to a furniture factory meant that power saws and tools could not be used until power was restored. The employees had to work with ambient light through windows.
Productivity would decrease, but not cease. And it returned to normal quickly once power was restored. Today, interruption of power for even a second to most furniture factories would immediately shut down their five-axis milling machines and CAM-assembly robots. Work in progress would often be damaged and lost. And after power is restored the CAM assembly systems may take up to an hour to re-boot, re-initialize, and re-start: in most businesses and industries that rely on digital equipment, production is almost always interrupted for a longer period than the electrical service interruption itself.
Thus, by the s, consumers and thus regulators paid somewhat more attention to service interruptions, particularly short duration interruptions. But it would be far too simplistic to attribute the increasing societal emphasis on power reliability only to the use of digital equipment. The "digital society" merely brought about an increasing sensitivity to very short interruptions.
In the bigger sense, the need for reliable electric power grew because society as a whole came to rely much more on electric power, period. Had digital equipment never been invented, if the world were entirely analog, there would still be the. Specific attention to "blinks" and short-term interruptions might receive somewhat less attention, and longer duration interruptions a bit more, than what actually occurs today. But overall, reliability of power would be just as crucial for businesses and private individuals. For these reasons, the power industry began to move toward quantitative, pro-active management of power system reliability: set targets, plan to achieve them, monitor progress, and take corrective actions as needed.
The most salient points about power system reliability are summarized in Table 1. Chapters 4,7, 8, 14, 21, 23, and 28 will discuss reliability and its planning and management in much further detail. It is more economical to move power at high voltage. The higher the voltage, the lower the cost per kilowatt to move power any distance. The higher the voltage, the greater the capacity and the greater the cost of otherwise similar equipment. Thus, high voltage lines, while potentially economical, cost a great deal more than low voltage lines, but have a much greater capacity.
They are only economical in practice if they can be used to move a lot of power in one block - they are the giant economy size, but while always giant, they are only economical if one truly needs the giant size. Utilization voltage is useless for the transmission of power. The application of these lower voltages for anything more than very local distribution at the neighborhood level results in unacceptably high electrical losses, severe voltage drops, and astronomical equipment cost. It is costly to change voltage level - not prohibitively so, for it is done throughout a power system that's what transformers do - but voltage transformation is a major expense which does nothing to move the power any distance in and of itself.
Power is more economical to produce in very large amounts. Claims by the advocates of modern distributed generators notwithstanding, there is a significant economy of scale in generation - large generators produce power more economically than small ones. Thus, it is most efficient to produce power at a few locations utilizing large generators.
The issue is more complicated than just a comparison of the cost of big versus small generation. Power Delivery Systems 6. Power must be delivered in relatively small quantities at a low to volt voltage level.
It must "pick up" power at a few, large sites generating plants and deliver it to many, many more small sites customers. It must somehow achieve economy by using high voltage, but only when power flow can be arranged so that large quantities are moved simultaneously along a common path line. Ultimately, power must be subdivided into "house-sized" amounts, reduced to utilization voltage, and routed to each business and home via equipment whose compatibility with individual customer needs means it will be relatively quite inefficient compared to the system as a whole.
Hierarchical Voltage Levels The overall concept of a power delivery system layout that has evolved to best handle these needs and "truths" is one of hierarchical voltage levels as shown in Figure 1. As power is moved from generation large bulk sources to customer small demand amounts it is first moved in bulk quantity at high voltage - this makes particular sense since there is usually a large bulk amount of power to be moved out of a large generating plant.
As power is dispersed throughout the service territory, it is gradually moved down to lower voltage levels, where it is moved in ever smaller amounts along more separate paths on lower capacity equipment until it reaches the customers. The key element is a "lower voltage and split" concept.
Thus, the 5 kW used by a particular customer - Mrs. Rose at Oak Street in Metropolis City - might be produced at a MW power plant more than three hundred miles to the north. Her power is moved as part of a MW block from plant to city on a kV transmission line to a switching substation. Here, the voltage is lowered to kV through a to kV transformer, and immediately after that the MW block is. A key concept is "lower voltage and split" which is done from three to five times during the course of power flow from generation to customer. Now part of a smaller block of power, Mrs.
Rose's electricity is routed to her side of Metropolis on a kV transmission line that snakes 20 miles through the northern part of the city, ultimately connecting to another switching substation. This kV transmission line feeds power to several distribution substations along its route,4 among which it feeds 40 MW into the substation that serves a number of neighborhoods, including Mrs. As it emerges from the low side of the substation distribution transformer at Rose's power flows along one particular feeder for two miles, until it gets to within a few hundred feet of her home.
Here, a much smaller amount of power, 50 kVA sufficient for perhaps ten homes , is routed to a service transformer, one of several hundred scattered up and down the length of the feeder. As Mrs. The secondary wiring splits the 50 kVA into small blocks of power, each about 5 kVA, and routes one of these to Mrs. Rose's home along a secondary conductor to her service drops - the wires leading directly to her house.
Over the past one hundred years, this hierarchical system structure has proven a most effective way to move and distribute power from a few large generating plants to a widely dispersed customer base. The key element in this structure is the "reduce voltage and split" function - a splitting of the power flow being done essentially simultaneously with a reduction in voltage.
Usually, this happens between three and five times as power makes its way from generator to customers. Each level consists of many units of fundamentally similar equipment, doing roughly the same job, but located in different parts of the system so as to "cover" the entire utility service territory. For example, all of the distribution substations are planned and laid out in approximately the same manner and do roughly the same job. All are composed of roughly similar equipment doing the same job. Some substations might be "larger" than others in both physical and capability terms - one could have four 50 MVA transformers and associated equipment, another only one 7 MVA transformer.
But both perform the same function for their area of the system, taking incoming power from sub-transmission, lowering voltage, splitting the power flow, and routing it onto distribution feeders for delivery in the neighborhoods around them. These constitute a "level" of the system, because all the power delivered everywhere flows through one such substation; in every part of the utility system, there is a "local" substation whose function is to provide the power for the neighborhoods around it.
Together, these substations constitute the "substation level" of the system. Their service areas fit together in a mosaic, each covering its piece of the service territory. Transmission lines whose sole or major function is to feed power to distribution substations are often referred to as "sub-transmission" lines. Likewise, the feeders the substations route power into are all similar in equipment type, layout, and mission, and all service transformers to which those feeders route power are similarly serving the same basic mission and are designed with similar planning goals and to similar engineering standards.
Thus, power can be thought of as flowing "down" through these various levels, on its way from power production and the wholesale grid to the energy consumers. As it moves from the generation plants system level to the energy consumers, the power travels through the transmission level, to the sub-transmission level, to the substation level, onto and through the primary feeder level, and onto the secondary service level, where it finally reaches the customer. Each level takes power from the next higher level in the system and delivers it to the next lower level in the system.
In almost all cases each flow of power is split into several paths at or shortly after the transition down to the next level. While each level varies in the types of equipment it has, its characteristics, mission, and manner of design and planning all share several common characteristics: Each level is fed power by the one above it, in the sense that the next higher level is electrically closer to the generation. Both the nominal voltage level and the average capacity of equipment drops from level to level, as one moves from generation to customer. Transmission lines operate at voltages of between 69 kV and 1, kV and have capacities between 50 and 2, MW.
By contrast, distribution feeders operate between 2. Each level has many more pieces of equipment in it than the one above. A system with several hundred thousand customers might have fifty transmission lines, one hundred substations, six hundred feeders, and forty thousand service transformers. As a result, the net capacity of each level number of units times average size increases as one moves toward the customer. A majority of service interruptions are a result of failure either due to aging or to damage from severe weather of transformers, connectors, or conductors very close to the customer, as shown in Figure 1.
Table 1. The net effect of the changes in average size and number of units is that each level contains a greater total capacity than the level above it - the service transformer level in any utility system has considerably more installed capacity number of units times average capacity than the feeder system or the substation system. Total capacity increases as one heads toward the customer because of noncoincidence of peak load which will be discussed in Chapter 3 and for reliability purposes.
This greater-capacity-at-every-lower-level characteristic is a deliberate design feature of most power systems, and required both for reliability reasons and to accommodate coincidence of load, which will be discussed in Chapter 3. Interruptions due to generation and transmission often receive the most attention because they usually involve a large number of customers simultaneously. However, such events are rare whereas failures and interruptions at the distribution level create a constant background level of interruptions.
The Transmission Level The transmission system is a network of three-phase lines operating at voltages generally between kV and kV. The term "network" means that there is more than one electrical path between any two points in the system Figure 1. Networks are laid out in this manner for reasons of reliability and operating flow - if any one element line fails, there is an alternate route and power flow is hopefully not interrupted.
In addition to their function in moving power, portions of the transmission system - the largest elements, namely its major power delivery lines - are designed, at least in part, for stability needs. The transmission grid provides a strong electrical tie between generators, so that each can stay synchronized with the system and with the other generators. This arrangement allows the system to operate and to function evenly as the load fluctuates and to pick up load smoothly if any generator fails - what is called stability of operation. A good deal of the equipment put into transmission system design, and much of its cost, is for these stability reasons, not solely or even mainly for moving power.
The Sub-Transmission Level The sub-transmission lines in a system take power from the transmission switching stations or generation plants and deliver it to substations along their routes. A typical subtransmission line may feed power to three or more substations. Often, portions of the transmission system - bulk power delivery lines, lines designed at least in part for stability as well as power delivery needs - do this too, and the distinction between transmission and sub-transmission lines becomes rather blurred.
Normally, sub-transmission lines are in the range of capacity of 30 MVA up to perhaps MVA, operating at voltages from With occasional exceptions, sub-transmission lines are part of a network grid - they are part of a system in which there is more than one route between any two points. Usually, at least two subtransmission routes flow into any one substation, so that feed can be maintained if one fails. The transmission and sub-transmission systems above the substation level usually form a network, as discussed above, with more than one power flow path between any two parts.
But from the substation on to the customer, arranging a network configuration would simply be prohibitively expensive. Thus, most distribution systems are radial - there is only one path through the other levels of the system. Typically, a substation occupies an acre or more of land, on which the various necessary substation equipment is located. Substation equipment consists of high and low voltage racks and busses for the power flow, circuit breakers for both the transmission and distribution level, metering equipment, and the "control house," where the relaying, measurement, and control equipment is located.
They are often equipped with tap-changing mechanisms and control equipment to vary their windings ratio so that they maintain the distribution voltage within a very narrow range, regardless of larger fluctuations on the transmission side. Very often, a substation will have more than one transformer. Two is a common number, four is not uncommon, and occasionally six or more are located at one site.
Having more than one transformer increases reliability - in an emergency, a transformer can handle a load much over its rated load for a brief period e. Equipped with from one to six transformers, substations range in "size" or capacity from as little as five MVA for a small, single-transformer substation, serving a sparsely populated rural area, to more than MVA for a truly large six-transformer station, serving a very dense area within a large city.
Since that equipment is needed in direct proportion to the transformer's capacity and voltage, and since it is needed only because a transformer is being added, it is normal to associate it with the transformer as a single planning unit - add the transformer, add the other equipment along with it. Substations consist of more equipment, and involve more costs, than just the electrical equipment. The land the site has to be purchased and prepared. Preparation is non-trivial. The site must be excavated, a grounding mat wires running under the substation to protect against an inadvertent flow during emergencies laid down, and foundations and control ducting for equipment must be installed.
Transmission towers to terminate incoming transmission must be built. Feeder getaways - ducts or lines to bring power out to the distribution system - must be added. The Feeder Level Feeders, typically either overhead distribution lines mounted on wooden poles or underground buried or ducted cable sets, route the power from the substation throughout its service area.
Feeders operate at the primary distribution voltage.
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The most common primary distribution voltage in use throughout North America is Worldwide, there are primary distribution voltages as low as 1. Some distribution systems use several primary voltages for example A feeder is a small transmission system in its own right, distributing between 2 MVA to more than 30 MVA, depending on the conductor size and the distribution voltage level. Normally between two and 12 feeders emanate from any one substation, in what has been called a dendritic configuration repeated branching into smaller branches as the feeder moves out from the substation toward the customers.
In combination, all the feeders in a. An average substation has between two and eight feeders, and can vary between one and forty. The main, three-phase trunk of a feeder is called the primary trunk and may branch into several main routes, as shown in the diagram. These main branches end at open points where the feeder meets the ends of other feeders - points at which a normally open switch serves as an emergency tie between two feeders.
In addition, each feeder will be divided, by normally closed switches, into several switchable elements. During emergencies, segments can be re-switched to isolate damaged sections and route power around outaged equipment to customers who would otherwise have to remain out of service until repairs were made. By definition, the feeder consists of all primary voltage level segments between the substations and an open point switch. Any part of the distribution level voltage lines three-phase, two-phase, or single-phase - that is switchable is considered part of the primary feeder.
The primary trunks and switchable segments are usually built using three phases, with the largest size of distribution conductor typically this is about MCM conductor, but conductor over 1, MCM is not uncommon, and the author has designed and built feeders for special situations with up to 2, MCM conductor justified for reasons other than maximum capacity e.
Often a feeder has excess capacity because it needs to provide back-up for other feeders during emergencies. The vast majority of distribution feeders worldwide and within the United States are overhead construction, wooden pole with wooden crossarm or post insulator. Only in dense urban areas, or in situations where esthetics are particularly important, can the higher cost of underground construction be justified.
In this case, the primary feeder is built from insulated cable, which is pulled through concrete ducts that are first buried in the ground. Underground feeder costs from three to ten times what overhead does. Many times, however, the first several hundred yards of an overhead primary feeder are built underground even if the system is overhead. Condition: Good.
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Previous issue Next issue. View all abstracts. All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.
Physical fitness is very important for athletes. It is because by knowing the physical fitness, an athlete can do excellent physical exercise, such as running exercises that can lead to physiological changes in athletes and physical fitness. However, based on observations made by the research team to the GSC, tools for monitoring athlete's fitness, especially heartbeat are not available in the GSC.
Based on discussions with GSC administrator, the need to develop a tool for monitoring the heartbeats of athletes, so that trainers can monitor athletes' condition, especially the athlete's heart condition. Based on this, it is deemed necessary to conduct research on the development of a tool to measure the heartbeats of athletes in the GSC. This research is an applied research in Science and Technology field to support sports facilities in GSC which is a business unit and also a lecture facility at Faculty of Sport and Health, Universitas Pendidikan Ganesha.
Based on the result of Blackbox testing that has been carried out, the heartbeats measurement prototype development based on IoT can be declared successful and feasible to be implemented. Beside using blackbox testing, the prototype was also tested by measuring the sensor voltage requirements in measuring heart rate and temperature. From that test, it can be concluded that any increase in temperature or heart rate requires a greater voltage, and vice versa.
This is because the sensor requires more power when the temperature or heart rate increases. Currently only few people are able to write with Balinese script. FSA algorithm is using six syllables that exist in the Balinese language structure and generates by font Bali simbar-b. In this test, the use of the Application has advantages a the characters generated can be copied and pasted in another document b completeness of Balinese script can be written c applications run on Linux OS, Windows, Mac OS.
Some of the drawback in this transliteration using a local database technology are some rule from Balinese Script not applied in algorithms. RA Division is responsible for data collection of the branches that affected by natural disasters to know the state of the branch after the disaster. But this time, the business process is running ineffective and inefficient. Therefore, RA Division requires an application that can predict the branches affected by natural disaster, namely Risk Dashboard.
This application is developed by waterfall methodology, ASP. This application makes the time needed to find a branch to be only a few seconds from the previous one which took almost a day. Tourism is a mainstay of Bali's original source of income. The object of tourist attraction in Bali is nature, culture, and a combination of nature and culture.
Buleleng is located in the north of Bali. Besides being famous for its stunning underwater scenery, it also has cultural richness in the form of shadow puppet craft. The purpose of this study was to create an Augmented Reality AR -based application of shadow puppet characters which were the handicrafts from Nagasepaha village, Buleleng. This AR application uses smartphones as shadow puppet recognition media for children or young generation virtually. So, the process of introducing shadow puppet becomes more interesting and easy to use.
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Users can run the application, then the application performs marker tracking. If the marker matches the reference data contained in the application, the application displays the shadow puppets in 3D on the smartphone screen. The information displayed is the name of the shadow puppet character along with the accompanying attributes, animated shadow puppet, the voice of the puppeteer who describes the puppet character.
The presence of AR, it is expected to increase the love of the younger generation for shadow puppet artwork from the village of Nagesepaha which is an icon of cultural heritage from North Bali. It's mean the program is running well and ready to use by end user. This paper presents a smart system prototype, which is on an Arduino platform, to managing solar panels and batteries installed on grid in a household. The batteries here are as storage of surplus power produced by solar panels in supplying loads. The aim of employing a smart system is to reduce use of power consumption from grid maximally and to increase the lifetime of batteries.
In the lab project experiment, we used some lamps with a 40 watt of the total of power to representing electric loads in a household and three power sources that are a power grid using PLN, a solar panel with a watt power output, and a Ah Battery. All of the power sources and the load connect in parallel, and operate in DC circuits with 12 Volt of operational voltage.
One of some testing, which was done about ten testing cases, showed that when the battery was in full charging, and the panel produced a maximum power, there was no power coming out from the grid to supply the loads instead the panel was solely supplying the loads.
Employing a smart system to manage solar panels on grid gives a highly significant advantage because the system programmed can do complex controls. This study aims to provide knowledge in order to save electricity consumption. The use of electrical energy is recorded at KWH meters.
Saving electricity means limiting the use of electrical energy according to need. The use of electrical energy is based on the use of electrical power. Technically, this dimmer serves to regulate the use of electrical power. Some electrical equipment has been equipped with dimmers to regulate the operation of the equipment in accordance with the user's want, yet there are still many electrical equipment that is not equipped with dimmers.
This is a problem in the efforts to save electricity. The method used in this study is applying passive components in electricity such as inductors, capacitors and resistors. These passive components are arranged to be used as filter circuits. With a 21 mH inductor with an air core, Farad's In the future, this research can be continued to improve the efficiency of electricity consumption by modifying passive filters. Internship program is important to be implemented as it can increase the competence of the university students. In fact, the program gives significant impact to the success of the students in industry.
Students freely choose their suitable place for the internship because suitable place will make students feel motivated and as a result they will be more competent. Industrial internship program is learning at the relevant industry, aimed to increase the competence of the students by introducing them with real working condition. Students are still find difficulty in deciding the suitable place for internship because of their low confidence or competence with related issue.
Now, students only need to fill the questionnaire and take the test. The result was that system can execute the process well and provide accurate recommendation for informatics students to determine suitable place for their internship program. Neural Network in the system is using the recurrent architecture to produce accurate optimal training. Interoperability is a component that contains information systems integration.
It provides an interface from multiple data sources to support data and information integrity between various information systems. This research is expected to provide the solution to the data integration architecture between systems that is running on HTTP protocol over internet. The integration model uses messaging services schemes and improve it with customization end-to-end encryption messages. It will provide any robust workflows to each step of development and management resources during design architecture and develop Datacenter ECR prototype. For the testing process, three 3 test process stages are performed: 1 White-box and 2 Black-box testing 3 Performance consistency testing.
One of the important variables in developing software is users' satisfaction of the software. Hence, there is a need to measure users' satisfaction of the software's that have been developed. The measurement of the users' reactions covers some aspects such as users' satisfaction, ease of use, efficiency, and whether the systems that have been developed can meet the users' needs.
This measurement is often called usability testing. It can be done using various instruments that have been developed by experts and communities in the field of computer.