26 research outputs found
Low thrust orbit transfer trajectory optimization
No full textPresented to the 11th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Heskett Center, Wichita State University, April 24, 2015.Research completed at Department of Aerospace Engineering, College of EngineeringIn recent years, all electric satellites have had a growing presence in the space industry. The 702-
SP family developed by Boeing is to be used for telecommunication satellites. This spawns the
need for analyzing mission scenarios in order to achieve the most efficient way of deploying
such satellites.
The purpose of this poster is to analyze the different approaches to Low Thrust Spacecraft
Trajectory optimization. One of the methods, developed by the author uses a feedback control
law which allows the user to minimize an arbitrary objective set by mission designers. It also
allows for a combination of objectives like minimum fuel and minimum time transfers.
Minimizing radiation damage is another objective that is of importance in these kind of scenarios
due to the long transfer times. The second method is a direct optimization routine. While this
method has been around longer, convergence to a solution is not guaranteed and depends on
initial guesses provided by the user. The third method is a combination of the first two methods
and allows for multi-objective optimization. Extensive research of existing literature has shown
that such a trajectory optimization method does not exist. The advantage of this method is that it
will be able to overcome the shortcomings of the individual components and provide a
comprehensive framework for mission designers to work with. The author will go over the
merits and drawbacks of the different methods as well as compare the performance of all the
methods for multiple scenarios. Some of these metrics will include rate of change of inclination,
radius and fuel mass.
In addition to this, the author will also introduce new performance objectives that could be of
interest to mission designers and will discuss the method of implementing them into all of the
mentioned methods.Graduate School, Academic Affairs, University Librarie
Evaluation of Digital Terrain Model (DTM) Accuracy Using Terrestrial Laser Scanning (TLS) in Flat and Steep Topographies
No full textThe advancement of geospatial technology has enabled various methods to produce high-accuracy Digital Terrain Models (DTMs), including Terrestrial Laser Scanning (TLS). This study evaluates the accuracy of TLS-derived DTMs in areas with varying topography at Universitas Diponegoro, Semarang. Data collection involved TLS, Total Station, and Leveling for georeferencing and accuracy assessment. The analysis included DTM visualization, RMSEz and LE90 calculations, and paired t-tests. Results show the TLS-derived DTM meets Class 1 accuracy standards for a 1:1000 map scale. Visualization demonstrated TLS's ability to represent both steep and flat terrain in detail, including contours and breaklines. The statistical test yielded a p-value of 0.710, indicating no significant difference between TLS and terrestrial data. The evaluated accuracy metrics are essential for assessing the reliability of TLS in real-world mapping. The results confirm TLS's capability to produce consistent and detailed terrain models, supporting its use in high-precision spatial applications such as infrastructure planning, environmental monitoring, and disaster mitigation. Therefore, TLS is a reliable method for generating high-quality DTMs across diverse topographic conditions
Migration-aware Network Services with Edge Computing
No full textThe development of Multi-access edge computing (MEC) has resulted from the requirement for supporting next generation mobile services, which need high capacity, high reliability and low latency. The key issue in such MEC architectures is to decide which edge nodes will be employed for serving the needs of the different end users. Here, we take a fresh look into this problem by focusing on the minimization of migration events rather than focusing on maximizing usage of resources. This is important because service migrations can create significant service downtime to applications that need low latency and high reliability, in addition to increasing traffic congestion in the underlying network. This paper introduces a priority induced service migration minimization (PrISMM) algorithm, which aims at minimizing service migration for both high and low priority services, through the use of Markov decision process, learning automata and combinatorial optimization. We carry out extensive simulations and produce results showing its effectiveness in reducing the mean service downtime of lower priority services and the mean admission time of the higher priority services.Embedded System
Strategi Kepolisian Dalam Meminimalisir Perdagangan Minuman Beralkohol yang Dilakukan Pedagang Gerobak Motor Di Jalan Juanda Melalui Pendekatan Penal dan Non Penal (studi Kasus Polrestas Pekanbaru)
No full textSales is a concrete or carried out to move a product, both in the form of goods and services, from producers to consumers as a target for profit. As for in this paper the author explains about the rampant phenomenon of the trade in alcoholic beverages and how the strategy of the Pekanbaru Police Resort in minimizing the trade in alcoholic beverages, especially on Jalan Juanda, Pekanbaru City. On the other hand this phenomenon can cause a big problem for people who consume alcoholic beverages too much so that this can disturb and disrupt security and order in the community itself. The type of this study is descriptive with a combined qualitative method and criminological visualization. Where research that describes the picture of the actual situation in the form of photos and videos that the author obtained from the field. Then, there are two strategies to minimize this crime by using the Penal and Non Penal approaches. However, based on the results of the research that the author did in its implementation, it was still unstable because there were still many sales of alcoholic beverages freely circulating in the market without a permit. Furthermore, the conclusion that the author obtained in this study is that Pekanbaru Polretsa Members have worked hard in following up the trade in alcoholic beverages, especially in Juanda, but only sanctions and their application are still weak, so they do not give a deterrent effect to traders selling alcoholic beverages
Two altars from Užice
No full textThere are two altars in Užice with dedications L(ibero) p(atri) Cap() and Lib(ero) p(atri) C(). They have been for a very long time used as an argument for existence of Celtic settlement, later Roman municipium by the name Capedunum. Since such supposes are in a later time rejected, the author discusses about to what relate to shortened epithets C() and Cap(). Several other monuments founded in the course of the Drina and upper Lim point to the connections between Liber and Jupiter, and Liber's identification with Jupiter. The same shortened epithets has Jupiter on the altars from Karan Miljevina and Sikirici. Also, the number of founded Liber's altars in Užice and further on maybe the existence of Roman municipium on the area of nowdays Užice, but not with the name Capedunum
Le dimensioni dello spazio pictum negli affreschi di Andrea Delitio
No full textIl contributo si pone l’obiettivo di verificare le dimensioni congetturali, metriche e qualitative, degli affreschi rinascimentali realizzati da Andrea Delitio nella Cattedrale di Atri. La lettura dei dipinti da un punto di vista diverso rispetto a quello più consueto della critica d’arte, attraverso gli strumenti della rappresentazione grafica, hanno permesso di indagare lo spazio architettonico reale e dipinto, rivelan- do regole e incongruenze contenute nel disegno, nell’impianto prospettico degli affreschi.
Analizzare lo spazio scenico di un ciclo pittorico non è solo una questione di misura, di proporzioni, di rilevamento delle superfici che esso avvolge, benché questi dati siano importanti per comprendere l’organizzazione e il percorso visuale pensato dall’autore, entrano in gioco una serie di fattori da considerare per cogliere il superamento della dimensione fisica tracciata nel disegno, nella narrazione prospettica. Le sinopie celate nell’opera svelano i percorsi culturali, i tracciati visivi, gli espedienti pro- spettici che permettono di percepire la costruzione dell’immagine e i suoi significati, la trasposizione delle superfici dipinte in estensioni tridimensionali che oltrepassano lo spazio fisico delle pareti. Le illusioni dello spazio scenico, le tante dismisure riscontrate non compromettono le valenze del ciclo pittorico e del suo autore che è cosciente delle regole della prospettiva e della percezione, ma le adotta con un linguaggio fantasioso ibridato tra tradizione medioevale e nuovo gusto rinascimentale.
The contribution aims to verify the conjectural, metric and qualitative dimensions of the Renaissance frescoes painted by Andrea Delitio in the Cathedral of Atri. The reading of the paintings from a different point of view than the more usual one of art criticism, through the tools of graphic representation, allowed to investigate the real and painted architectural space, revealing rules and inconsistencies contained in the design, perspective layout of the frescoes. Analyzing the scenic space of a pictorial cycle is not only a matter of measurement, proportions, sur- veying the surfaces it envelops, although these data are important to understand the organization and visual path conceived by the author, a number of factors come into play that must be considered in or- der to grasp the overcoming of the physical dimension traced in the drawing, in the perspective narra- tive. The sinopites concealed in the work reveal the cultural paths, the visual tracings, the perspectival devices that allow us to perceive the construction of the image and its meanings, the transposition of the painted surfaces into three-dimensional extensions that transcend the physical space of the walls. The illusions of the scenic space, the many disproportions found do not compromise the values of the pictorial cycle and its author who is aware of the rules of perspective and perception, but adopts them with an imaginative language hybridized between medieval tradition and new Renaissance taste
PERAN PELATIH DALAM MENUMBUHKAN MOTIVASI ATLET PETANQUE PEMULA DI KABUPATEN BATANG HARI
No full textIn Batang Hari Regency, the sport of Petanque has shown positive development with the coaching of novice athletes by local clubs and sports federations. However, in practice, several problems have been identified, such as low athlete attendance at training sessions, a lack of seriousness in following the programme that has been drawn up, and a decline in enthusiasm when experiencing failure in competitions. This condition indicates that there are challenges in fostering the motivation of novice athletes that must be overcome by coaches by playing their role to the fullest. The purpose of this study is to determine the role of coaches in fostering the motivation of novice Petanque athletes in Batang Hari Regency. This study uses qualitative research because qualitative research methods allow researchers to gain a deep understanding of the issues being studied and answer research questions. In this study, the author took the coach as the key informant and the assistant coach and Batanghari Regency petanque athletes as supporting informants. The results of the study indicate that the role of coaches in fostering motivation among novice petanque athletes in Batang Hari Regency is very good in the intrinsic category for 7 people with a percentage of 7%, good in the category for 11 people with a percentage of 73%, and moderate in the category for 3 people with a percentage of 20%. The Role of Coaches in Fostering Motivation Among Beginner Petanque Athletes in Batanghari Regency Extrinsic indicators: 3 people in the excellent category with a percentage of 20%, 10 people in the good category with a percentage of 67%, and 2 people in the moderate category with a percentage of 13%. The role of coaches in fostering motivation among novice petanque athletes in Batang Hari Regency as a whole: 1 person in the excellent category with a percentage of 7%, 13 people in the good category with a percentage of 86%, and 1 person in the moderate category with a percentage of 7%. The conclusion of this study is that the role of coaches in fostering motivation among beginner petanque athletes in Batang Hari Regency is good for 13 people with a percentage of 86%
Nilai Sosial Dalam Novel Selembar Itu Berarti Karya Suryaman Amipriono
No full textSocial value is something that becomes a measure, and an appropriate assessment is not an attitude aimed at in the life of society. Social values serve as a reference to behavior in interacting with others so that their existence can be accepted in society. The problem that is studied in this study is (1) How is the social value related to the value of loves in the sheet is means the work of Suryaman Amipriono?, (2) How does the social values related to responsibility in the sheet is means the works of Suryan Amipryono?, (3) How is social value associated with the values of life harmony in the sheet is means novel work of Suryaman Amipriono?. The aim of this study is to collect, describe, analyze, and interpret data on social values related to the intention of compassion, the value of responsibility, and the values of compatibility of life in the novel sheet is means the work of Suryaman Amipriono. The main theory used by the author is the Zubaedi theory (2012). The approach used is a qualitative approach to the type of library research. The method used is descriptive. The data collection technique used is hermeneutic. The data analysis techniques used by the authors are content analysis techniques. The result of the research of social value in the novel sheet is means the work of Suryaman Amipriono there are 47 data consisting of 23 data of value of loves by the characters of Ibu Hera, Putri, Bu Imah, Arya, Nisa, Bu Reni, Pak Wildan, and Atri; 15 data of the value of responsibility demonstrated by the figures of Putri, Ibu Hera, Pak Lingga, Diaz, Arya, Nisa, Atri, Bu Imah, and Bu Lina; and 9 data of life harmony shown by characters Diaz, Putri, Pak Lingga, Bu Imah, Nisa, Pak Azwar, and Pak Wildan. Suryaman Amipriono's work describes an attitude and action in social life that is seen from the values of loves consisting of devotion, help, family, loyalty, and care; the value of responsibility consists of a sense of possession, discipline, and empathy: and the worth life harmony consisting on justice, tolerance, cooperation, and democracy. Social values that are more dominant in this study are social values related to the value of affection. The value of affection consists of five aspects, namely devotion, helping, kinship, loyalty, and caring. Aspects of devotion found 5 data, aspects of mutual assistance found 4 data, aspects of kinship found 8 data, aspects of loyalty found 2 data, and aspects of caring found 4 data
STUDY OF BIFURCATION ANALYSIS FOR DYNAMIC VOLTAGE STABILITY IN POWER SYSTEM
No full text N . Amjady1, * , M . R . Ansari Shahreza2    1 . Professor , Electrical & Computer Engineering Faculty , Semnan University , Semnan, Iran  2 . M . Sc. Student , Electrical & Computer Engineering Faculty, Semnan University, Semnan, Iran  * Corresponding Author: [email protected]   Abstract  Voltage collapse is an inherently nonlinear phenomenon and it is suitable to use nonlinear analysis techniques such as bifurcation theory to study voltage collapse and to devise ways of avoiding it. For a power system, there are three different kinds of bifurcation points: the singularity induced bifurcation, saddle-node and hopf bifurcation.These three bifurcation sets are the boundary of the feasible region of the power system stability. When one equilibrium point passes through the boundary, the system will lose its stability. This paper focuses on bifurcation analysis for dynamic voltage stability. It also studies the eigenvalues behavior of the power system close to bifurcation points. This paper considers both unreduced Jacobian matrix eigenvalues and reduced ones, and it compares their results, too. MATLAB software has been used in this paper.    Keywords: Voltage C ollapse, Voltage S tability, Bifurcation A nalysis, Unreduced Jacobian M atrix, Reduced Jacobian M atri
