scholarly journals Autonomous Recovery from Spacecraft Plan Failures by Regulatory Repair While Retaining Operability

Aerospace ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 40
Author(s):  
Rui Xu ◽  
Chao Chen ◽  
Siyao Lu ◽  
Zhaoyu Li
Keyword(s):  
Causal Analysis ◽  
Space Environment ◽  
Ground Control ◽  
Search Process ◽  
Execution Plan ◽  
Factors Associated ◽  
Failure State ◽  
Long Time ◽  
Autonomous Recovery ◽  
Partial Execution

Pre-designed spacecraft plans suffer from failure due to the uncertain space environment. In this case, instead of spending a long time waiting for ground control to upload a feasible plan in order to achieve the mission goals, the spacecraft could repair the failed plan while executing another part of the plan. This paper proposes a method called Isolation and Repair Plan Failures (IRPF) for a spaceship with durable, concurrent, and resource-dependent actions. To enable the spacecraft to perform some actions when a plan fails, IRPF separates all defective actions from executable actions in the pre-designed plan according to causal analysis between the failure state and the established plan. Then, to address the competition between operation and repair during the partial execution of the plan, IRPF sets up several regulatory factors associated with the search process for a solution, and then repairs the broken plan within the limits of these factors. Experiments were carried out in simulations of a satellite and a multi-rover system. The results demonstrate that, compared with replanning and other plan-repair methods, IRPF creates an execution plan more quickly and searches for a recovery plan with fewer explored state nodes in a shorter period of time.

scholarly journals PENGARUH GANGGUAN LINGKUNGAN ANTARIKSA PADA SISTEM ELEKTRONIK LAPAN-TUBSAT (EFFECT OF SPACE ENVIRONMENT DISTURBANCE IN LAPAN-TUBSAT SATELLITE)

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Nayla Najati
Keyword(s):  
Real Time ◽  
South Atlantic ◽  
Space Environment ◽  
Normal Operation ◽  
Single Event ◽  
South Atlantic Anomaly ◽  
Long Time ◽  
Latch Up

LAPAN-TUBSAT has been operated more than five years. During the operation, LAPAN-TUBSAT faces several anomaly. It could be observed by using real time telemetry and long time telemetry. When and where an anomaly appeared can be detected with long time telemetry. Anomaly event on LAPAN-TUBSAT’s PCDH is caused by Single Event Latch-Up (SEL) that happen in scale of weeks.These conditions required LAPAN-TUBSAT operators to take action in order to make LAPAN-TUBSAT back to normal operation. This paper describes statistic of SEL that occur in LAPAN-TUBSAT. Almost 70% of SEL event take place at South Atlantic Anomaly (SAA) and the rest at polar. Keywords: SEL, LAPAN-TUBSAT, Real time telemetry, Long time telemetry, PCDH

scholarly journals Nanosatellites for Biology in Space: In Situ Measurement of Bacillus subtilis Spore Germination and Growth after 6 Months in Low Earth Orbit on the O/OREOS Mission

Life ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 1 ◽  
Author(s):  
Wayne L. Nicholson ◽  
Antonio J. Ricco
Keyword(s):  
Bacillus Subtilis ◽  
Optical Density ◽  
Spore Germination ◽  
Space Environment ◽  
Ground Control ◽  
Earth Orbit ◽  
Growth Responses ◽  
Germination And Growth ◽  
Control Samples

We report here complete 6-month results from the orbiting Space Environment Survivability of Living Organisms (SESLO) experiment. The world’s first and only long-duration live-biology cubesat experiment, SESLO was executed by one of two 10-cm cube-format payloads aboard the 5.5-kg O/OREOS (Organism/Organic Exposure to Orbital Stresses) free-flying nanosatellite, which launched to a 72°-inclination, 650-km Earth orbit in 2010. The SESLO experiment measured the long-term survival, germination, metabolic, and growth responses of Bacillus subtilis spores exposed to microgravity and ionizing radiation including heavy-ion bombardment. A pair of radiation dosimeters (RadFETs, i.e., radiation-sensitive field-effect transistors) within the SESLO payload provided an in-situ dose rate estimate of 6–7.6 mGy/day throughout the mission. Microwells containing samples of dried spores of a wild-type B. subtilis strain and a radiation-sensitive mutant deficient in Non-Homologoous End Joining (NHEJ) were rehydrated after 14, 91, and 181 days in space with nutrient medium containing with the redox dye alamarBlue (aB), which changes color upon reaction with cellular metabolites. Three-color transmitted light intensity measurements of all microwells were telemetered to Earth within days of each 24-hour growth experiment. At 14 and 91 days, spaceflight samples germinated, grew, and metabolized significantly more slowly than matching ground-control samples, as measured both by aB reduction and optical density changes; these rate differences notwithstanding, the final optical density attained was the same in both flight and ground samples. After 181 days in space, spore germination and growth appeared hindered and abnormal. We attribute the differences not to an effect of the space environment per se, as both spaceflight and ground-control samples exhibited the same behavior, but to a pair of ~15-day thermal excursions, after the 91-day measurement and before the 181-day experiment, that peaked above 46 °C in the SESLO payload. Because the payload hardware operated nominally at 181 days, the growth issues point to heat damage, most likely to component(s) of the growth medium (RPMI 1640 containing aB) or to biocompatibility issues caused by heat-accelerated outgassing or leaching of harmful compounds from components of the SESLO hardware and electronics.

Borrowing Decision of Households: An Examination of the Information Search Process

2017 ◽  
Vol 28 (1) ◽  
pp. 95-106 ◽  
Author(s):  
Lu Fan ◽  
Swarn Chatterjee
Keyword(s):  
Educational Attainment ◽  
Information Search ◽  
Financial Literacy ◽  
Search Behavior ◽  
Financial Knowledge ◽  
Search Process ◽  
Financial Capability ◽  
Factors Associated ◽  
Information Search Behavior ◽  
Underserved Groups

This study uses the 2009 National Financial Capability Study dataset to examine the factors associated with information search behavior by consumers when applying for a loan. The results indicate that financial literacy, perceived financial knowledge, educational attainment, and engaging the services of a financial professional are positively associated with the likelihood of information search among consumers. The results also indicate that consumers from the traditionally underserved groups, who would benefit most from better information search, were the least likely to use it. The results of this study are important to consumers, educators, and financial practitioners. A discussion of the implications addressing the association between financial literacy, information search behavior, and household financial capability within the population is also included in this study.

Techniques Used by Elite Women Gymnasts Performing the Handspring Vault at the 1987 Pan American Games

1990 ◽  
Vol 6 (1) ◽  
pp. 29-55 ◽  
Author(s):  
Yoshiaki Takei
Keyword(s):  
Vertical Velocity ◽  
Large Change ◽  
Great Distance ◽  
Successful Performance ◽  
Factors Associated ◽  
Long Time ◽  
Mechanical Factors ◽  
Pan American ◽  
Female Gymnasts ◽  
Short Time

The purposes of this study were (a) to determine the mechanical factors associated with successful performance of women’s handspring vault and (b) to contrast the findings to those of men to gain insight for improvement of performance. The subjects were 24 female gymnasts in the 1987 Pan American Games. Significant correlations indicated that the following were important determinants for successful results: (a) large horizontal velocity (VH) and distance of hurdle; (b) large vertical velocity (Vv) at touchdown (TD) on board, a large change of Vv on board, and a short time of board contact; (c) large VH and Vv at takeoff (TO) from board; (d) short time of horse contact; (e) large VH and Vv at TO from horse; (f) high body CG at TO from horse; and (g) great distance and height and a long time of postflight. Comparisons revealed that women had significantly smaller VH and Vv at TD on horse and departed from it with significantly smaller VH and Vv than men. This resulted in significantly less height and distance as well as a shorter time of postflight for women even after adjusting for horse height and subject physique.

scholarly journals Performance Analysis of Hashing Methods on the Employment of App

2018 ◽  
Vol 8 (5) ◽  
pp. 3512
Author(s):  
Anton Yudhana ◽  
Abdul Fadlil ◽  
Eko Prianto
Keyword(s):  
Performance Analysis ◽  
Large Data ◽  
Search Process ◽  
Administrative Process ◽  
Know How ◽  
Average Value ◽  
Long Time ◽  
Access Data

The administrative process carried out continuously produces large data. So the search process takes a long time. The search process by hashing methods can save time faster. Hashing is methods that directly access data in a table by making references to the key that hashing becomes the address in the table. The performance analysis of the hashing method is done by the number of 18 digit character values. The process of analysis is done on applications that have been implemented in the application. The algorithm of hashing method analyzed is progressive overflow (PO) and linear quotient (LQ). The main purpose of performance analysis of hashing method is to know how gig the performance of each method. The results analyzed showed the average value of collision with 15 keys in the analysis of 53.3% yield the same value, while 46.7% showed the linear quotient has better performance.

scholarly journals Pemetaan Industri di Kota Batam Menggunakan Mobile GIS Berbasis Android

2017 ◽  
Vol 1 (1) ◽  
pp. 1-4
Author(s):  
Zaki A Agha ◽  
Andy Triwinarko ◽  
Baigo Hamuna
Keyword(s):  
Research And Development ◽  
Search Process ◽  
Gis Application ◽  
Mobile Gis ◽  
Digital Maps ◽  
Gis Applications ◽  
Long Time

Android-based mobile GIS application is a service that combines digital maps in vector and smartphone media to search industry in Batam. This application is online. Currently, the information presented only provide location of region, users who are not familiar with the location will be difficult or take a long time to find the location of industry. Therefore it is necessary to design an application that is able to provide information on the location of industries in Batam. This thesis did research and development of Android-based mobile GIS applications to provide information on the location of industry in Batam. These applications have been built with the ability to show a map of Batam are taken from GeoServer, handle the search process, displays information and maps location of industry as desired user.

scholarly journals Penerapan Algoritma Horspool pada Aplikasi Katalog Buku Perpustakaan

2019 ◽  
Vol 1 ◽  
pp. 881
Author(s):  
Fince Tinus Waruwu ◽  
Rivalri Kristianto Hondro
Keyword(s):  
Reference Material ◽  
General Public ◽  
Search Algorithm ◽  
String Matching ◽  
Search Algorithms ◽  
Library Services ◽  
Search Process ◽  
Library Book ◽  
Long Time ◽  
Time And Energy

The library is a place that provides various types of reading books as reference material for students, students, educators and the general public. The library certainly provides various types of books that are different according to their needs. Finding books that are needed in a library with a large number of books certainly takes a long time and energy. In supporting library services and providing convenience for visitors, an application is built that helps visitors find the books they need to not need a long time and effort. In the book catalog application it is necessary to apply a search algorithm (string matching). Search algorithms help enders in finding the books they need. The search algorithm applied to the library book catalog application is the Horspool algorithm. Horspool algorithm is one algorithm that is widely used in the search process. By applying the Horspool algorithm in the library book catalog application can be faster and facilitate the process of finding the title of the book.

scholarly journals Analysis of Factors Related to The Documentation of Nursing Care

2020 ◽  
Vol 9 (2) ◽  
pp. 503-514
Author(s):  
Fitra Mayenti ◽  
Yulastri Arif ◽  
Vetty Priscilla
Keyword(s):  
Nursing Care ◽  
Individual Factors ◽  
High Educational Level ◽  
Nursing Documentation ◽  
Head Nurse ◽  
Cross Sectional ◽  
Level Of Education ◽  
Factors Associated ◽  
Long Time ◽  
High Educational

Nursing documentation is written evidence of the implementation of nursing care, but in some hospitals documenting nursing care is still  problem and  far from the Indonesian Ministry of Health, Which is 80%.  This study aimed to determine the factors associated with Nursing documentation of inpatient care at the Ibnu Sina Islamic Hospital Pekanbaru. The design of this study was observational cross sectional. A sample of 82 nurses used a proportional random sampling technique.The results showed that there individual factors 72 % were  early adult nurses, 51,2 % were old nurse with long time, 95,1% were high educational level. Organization factors showed that there 70,7 % were head nurse good category, 75,5% were employee available category, 52, 4% were nursing care good category.There were significant differences of length of work and level of education with documentation of nursing care.

scholarly journals Magnitude and factors associated with anti-malarial self-medication practice among residents of Kasulu Town Council, Kigoma-Tanzania

2019 ◽  
Vol 19 (3) ◽  
pp. 2457-2461
Author(s):  
Stanley Mwita ◽  
Omary Meja ◽  
Deogratias Katabalo ◽  
Catherine Richard
Keyword(s):  
Health Care Services ◽  
Cross Sectional Study ◽  
P Value ◽  
Self Medication ◽  
Cross Sectional ◽  
Medication Practice ◽  
Factors Associated ◽  
Care Services ◽  
Long Time ◽  
The Cost

Background: Anti- malarial self-medication practice in Africa is very common. It is considered as an alternative way for people who cannot afford the cost of health care services. This study was conducted to assess the magnitude and factors associated with anti-malarial self-medication practice among residents of Kasulu Town Council.Materials and methods: The study was a descriptive cross sectional study. Two hundred and eighty consenting respondents were selected by systematic random sampling and interviewed with the aid of a semi structured questionnaire to assess anti-malarial self- medication practice. A p value of less than 0.05 was considered statistically significant, at 95% confidence interval.Results: Prevalence of anti-malarial self-medication was (69.6%). Majority of the respondents (83.1%) reported that, they did not get better after self- medication. About 36% of the respondents metioned time taken in health facilities as the main factor for self- medication.Conclusion: This study revealed that, self-medication practice is very common among community members in Kasulu district. The main reasons identified for self-medication was long time taken to get treatment in health facilities.Keywords: Anti-malarial, Self- medication, Practice, Kasulu, Tanzania.

scholarly journals ATLAS Global Shares implementation in PanDA

2019 ◽  
Vol 214 ◽  
pp. 03025 ◽  
Author(s):  
Fernando Barreiro Megino ◽  
Alessandro Di Girolamo ◽  
Kaushik De ◽  
Tadashi Maeno ◽  
Rodney Walker
Keyword(s):  
Data Locality ◽  
Workload Management ◽  
Execution Plan ◽  
Batch Systems ◽  
Long Time ◽  
Stream Control ◽  
Computing Grid ◽  
Definition Of ◽  
Grid Resources ◽  
Distributed Analysis

PanDA (Production and Distributed Analysis) is the workload management system for ATLAS across the Worldwide LHC Computing Grid. While analysis tasks are submitted to PanDA by over a thousand users following personal schedules (e.g. PhD or conference deadlines), production campaigns are scheduled by a central Physics Coordination group based on the organization’s calendar. The Physics Coordination group needs to allocate the amount of Grid resources dedicated to each activity, in order to manage sharing of CPU resources among various parallel campaigns and to make sure that results can be achieved in time for important deadlines. While dynamic and static shares on batch systems have been around for a long time, we are trying to move away from local resource partitioning and manage shares at a global level in the PanDA system. The global solution is not straightforward, given different requirements of the activities (number of cores, memory, I/O and CPU intensity), the heterogeneity of Grid resources (site/HW capabilities, batch configuration and queue setup) and constraints on data locality. We have therefore started the Global Shares project that follows a requirements-driven multi-step execution plan, starting from definition of nestable shares, implementing share-aware job dispatch, aligning internal processes with global shares and finally implementing a pilot stream control for controlling the batch slots that keeps late binding. This contribution will explain the development work and architectural changes in PanDA to implement Global Shares, and describe how the Global Shares project has enabled the central control of resources and significantly reduced manual operations.

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