2,780 research outputs found
Regional validation of retracked sea levels from SARAL/Altika over the South China sea and adjacent seas
This paper focuses on assessing the quality of sea level anomaly (SLA) data from the new generation of Ka-band SARAL/AltiKa satellite altimetry over the continental shelf of the South China Sea. The region consists of peninsulas, shallow seas, and small islands that produce complicated altimetric waveform patterns. The improved-accuracy of SLAs data from the MLE4, Ice1 and Ice2 retrackers which are provided in the AVISO-Sensor Geophysical Data Records (SGDR) were optimized in this study. The quality of retracked SLAs is assessed by making comparison with tide gauge data from six stations. In general, the percentage of data availability of Ice-1 retracker is superior ( > 68%) to those of MLE- 4 and Ice-2 retrackers. The improvement of percentage (IMP) also shows that Ice-1 retracker improves the standard deviation > 12% better than those of Ice-2 retracker. Over complex areas of Lubang and Ko Taphao Noi, the temporal correlation of Ice-1 retracker is superior (r > 0.80) to those of MLE4 and Ice-2 retrackers (r 5.8) and lower RMS error ( < 34 cm) than those of Ice-1 retracker. It can be concluded that the Ice-1 and Ice-2 retrackers were superior for the coastal region of Maritime Continent
Microstructure development, mechanical and tribological properties of a semisolid A356/xSiCp composite
This paper presents the results of experimental investigation on microstructure (size and morphology of eutectic Si), impact toughness and sliding wear properties of A356 Al-Si alloy and composites containing 10, 20 and 25 wt% of SiCp reinforcement produced by semisolid stirring technique. The results revealed that an increase in SiCp content leads to a reduction in the size of eutectic Si and also changes its morphology from plate-like to equiaxed. Furthermore, addition of 10 and 20 wt% silicon carbide reinforcement decreased the impact toughness by 6 and 18%, respectively. A356/25wt%SiCp composite registered the lowest impact toughness with reduction of 33% due to debonding and agglomeration of SiCp in the matrix. The sliding wear results showed that the wear resistance of the composites was significantly higher than that of the matrix alloy due to the increase in hardness as well as reduction in the size and also morphology transformation of eutectic silicon with increase in SiCp content. However, the existence of particle-porosity clustering with increasing the SiCp content to 25 wt% played a significant role in deteriorating the wear behavior of the composite
Impact of Arrivals on Departure Taxi Operations at Airports
Aircraft taxi operations are a major source of fuel burn and emissions on the ground. Given rising fuel prices and growing concerns about the contributions of aviation to air pollution and greenhouse gas emissions, recent research aims to develop strategies to reduce fuel burn at airports. In order to develop such strategies, an understanding of taxi operations and the factors that affect taxi-out times is required. This paper describes an analysis of taxi-out times at two major U.S. airports in order to identify the primary causal factors affecting the duration of taxi-out operations. Through an analysis of departures out of John F. Kennedy International Airport and Boston Logan International Airport, several variables affecting taxi-out times were identified, including primarily the number of arrivals and number of departures during the taxi-out operation of an aircraft. Previous literature suggests that the number of arrivals on the surface has limited influence on taxi-out times; however, this analysis demonstrates that the number of arrivals is in fact significantly correlated with taxi-out times. Furthermore, we find that arrivals have a greater impact on taxi-out times under runway configurations where there is increased interaction between arrivals and departures
CAWRES: A waveform retracking fuzzy expert system for optimizing coastal sea levels from Jason-1 and Jason-2 satellite altimetry data
This paper presents the Coastal Altimetry Waveform Retracking Expert System (CAWRES), a novel method to optimise the Jason satellite altimetric sea levels from multiple retracking solutions. CAWRES' aim is to achieve the highest possible accuracy of coastal sea levels, thus bringing measurement of radar altimetry data closer to the coast. The principles of CAWRES are twofold. The first is to reprocess altimeter waveforms using the optimal retracker, which is sought based on the analysis from a fuzzy expert system. The second is to minimise the relative offset in the retrieved sea levels caused by switching from one retracker to another using a neural network. The innovative system is validated against geoid height and tide gauges in the Great Barrier Reef, Australia for Jason-1 and Jason-2 satellite missions. The regional investigations have demonstrated that the CAWRES can effectively enhance the quality of 20 Hz sea level data and recover up to 16% more data than the standard MLE4 retracker over the tested region. Comparison against tide gauge indicates that the CAWRES sea levels are more reliable than those of Sensor Geophysical Data Records (SGDR) products, because the former has a higher (≥0.77) temporal correlation and smaller (≤19 cm) root mean square errors. The results demonstrate that the CAWRES can be applied to coastal regions elsewhere as well as other satellite altimeter missions
Implementasi Kurikulum Tingkat Satuan Pendidikan Bidang Studi IPS Pada Madrasah Tsanawiyah Swasta Al-furqan Bambi Kabupaten Pidie
Unit Level Education Curriculum (KTSP) curriculum constitutes one of constituent in teaching and learning process. This research intent to inspect, observe and describe the implementation Unit Level Education Curriculum in particular area Social study at MTs Swasta Al Furqan Bambi Pidie Regency, as follows: (1) Program developmental activities syllabi, RPP and SKL; (2) Material preparations for teaching; (3) Learning performings; and (4) Estimation perfor-ming/evaluations. This research utilizes qualitative descriptive method. Data collecting tech that is utilized is observation, interview and documents study. Subjects in this observational were principal, vice principal, and social study teachers. Result observational to point out that KTSP's implementation on that social study can be seen of: (1) Syllabus makings performing and RPP which made by Social study teacher done by personaland groups in MGMP, but they experience interference in determine indicator in point; (2) Material preparations teach that did by Social study teacher as LKS and module, really help student in completes each competences; (3) Learning performing that did by teacher utilizing close to get center on child (child centered) through active learning, creative, effective, and rejoicing by use of infrastucture media and medium whatever available; (4) Evaluate learningthat did by Social study teacher in forms process estimation as dry run of daily, common dry run or final examination, and task estimation as application of task that performed by individual or group
Practical Database Design for Industrial Maintenance System
This paper describes how a database design can play
an important role for developing practical industrial
maintenance system. The good database design will in return give a better information sharing and good system in term of data accessibility. The design of the database are presented and illustrated by a case. The preliminary result presented to show that is possible to access a more correct view of the situation in the system development and thereby obtain a better base for making maintenance decisions. The database supports the development of applications e.g. for monitoring the performance of a maintenance in the production, for deciding the most appropriate maintenance policy or for simulating possible maintenance solutions
Self-efficacy of catering students of Faculty Technical and Vocational Education, University Tun Hussein Onn Malaysia in the Field of Career to be pursued
The increasing rate of unemployed graduates in Malaysia has received alarming attention in recents years. One of the factors that contribute to the unemployment problem is the lack of self-efficacy among graduates in making career choices. Therefore, this study was conducted to identify the self-efficacy of catering students to make decision on career field options to be pursued either as a teacher, hospitality employee or entrepreneur. The design of this study is a quantitative descriptive study through survey and questionnaire is used as research instruments. A total of 66 catering students of year 3 and 4 from Faculty of Technical and Vocational Education (FPTV) were selected as the study sample. The data obtained were analyzed using Statistical Package for Social Science (SPSS) version 22.00 software involving mean, standard deviation, and ANOVA. The results showed that the mean scores of self-efficacy of catering students were high to become teachers (M= 4.11, SD=0.617) and followed by hospitality employee (M= 3.87, SD= 0.574) and entrepreneurs (M= 3.93, SD=0.514). However, there was no significant difference between the three career fields with a value of p = 0.052. In conclusion, catering students have high self-efficacy in venturing into the field of career when graduating from university. Graduates need to see the importance of enhancing self-efficacy because it opens paths for career opportunities and advancement
Pengetahuan, Sikap dan Perilaku Kaitannya dengan Masalah Demam Berdarah Dengue di Daerah Pamulang, Kabupaten Tangerang, Propinsi Banten
Dengue Hemorrhagic Fever (DHF) is a disease thai still cause health problems in Indonesia. Dengue cases are still high to the understanding of a phenomenon that is not only seen from the health aspect alone, but associated with other symptoms that exist in this society means the emergence of DHF can not be separated from the low environmental quality, because public awareness to preserve the environment for mosquito vector transmission DBD does not have the opportunity to breed relatively less. Mobility is also supported by the higher population and settlements which the spread of increasingly dense and more widespread transmission of dengue. Therefore research has been done on the dynamics of dengue transmission in the area Pamulang Tangerang District, Banten Province. Research using quantitative and qualitative approaches. Kuantatif approach to collecting data through interviews using a questionnaire. The number of samples of600 people and as a respondent is the head of the family. Approach was qualitative data collection through in-depth interviews of a number of informants consisting of community leaders, religious leaders, youth, and the head of PKK health center. The results showed the public's knowledge about dengue hemorrhagic fever is good enough. Generally the respondents knew about the cause of DHF is due to Aedes aegypti mosquitoes. Symptoms and modes of transmission of DHF also well known by most respondents. They claimed that the symptoms first dengue fever, red spots dikulit, first and appetite is less. Nevertheless behavior towards the prevention of dengue transmission is still less reiatih. Most respondents claimed not implement the principle of 3M. They only carry out service projects that are less focused on the extraction of regular water and shelter is always closed, burn or bury the old stuff can be suspected of developing a mosquito biuknya dengue infection. Supported high population mobility due to frequent traveling and staying in other regions. This enables the transmission and spread of DHF in the community will take place
A review of gelatin: properties, sources, process, applications, and commercialisation
This review begins with a discussion of the general properties of gelatin and its sources, particularly in
the food and health industries, and then briefly address the status quo of gelatin in today’s market.
Apart from the basic chemical compounds and gelatin types, this paper also discussed the commercialisation
of gelatin. This study also highlights the production of conventional gelatin and its current method
of processing, i.e. enzymatic hydrolysis. In addition, the variety of raw materials of collagen is outlined
and briefly broached the plant hydrocolloids which have been labeled as ’veggie-gelatin’. With regard
to the potential and market stability of gelatin, its recent studies are summarised in this paper.
Accordingly, this paper focuses on assessing the general utilities of the various sources of collagen as gelatin
derivatives. At that basis, the aim of this review is to provide an insight into gelatin in current applications,
market value and progress in gelatin extraction
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