Structure Design of the Database in the INS/Database Matching Navigation System

2013 ◽  
Vol 760-762 ◽  
pp. 1930-1935
Author(s):  
Fan Ming Liu ◽  
Xing Wei ◽  
Fang Ming Li

Using the geophysical field data matching navigation could improve the concealment of the underwater vehicle, and it is also an important navigation technology in the future. Using the database to save the navigation data not only could overcome the drawbacks when using the files to storage the data but also integrated the different database together. The QNX Database is used to be the database management system (DBMS) of the INS/Database matching navigation system. According to the needs of the INS/Database matching navigation system and the relationship of the geophysical field data, the structure of geophysical field data database is designed and implemented. The result shows that the DBMS has well real-time performance, reliability and scalability. It meets the requirements of the DBMS.

2011 ◽  
Vol 48 (1) ◽  
Author(s):  
Dina Ribbink ◽  
Christian Hofer ◽  
Martin Dresner

An investigation is conducted on the effect of financial distress on customer service levels in the U.S. airline industry. Using data from the first quarter of 1998 to the third quarter of 2006, we employ a seemingly unrelated regressions (SUR) model to analyze the impact of financial distress on three measures of customer service. We find that higher financial distress is associated with better on-time performance of airlines and fewer lost bags. The relationship of airline financial distress to the number of bumped customers, however, is insignificant.


2012 ◽  
Vol 479-481 ◽  
pp. 2529-2532
Author(s):  
Ying Zhang ◽  
Zhen Wei Zhang

This paper mainly focuses on the numerical simulation of flow velocity aiming to obtain the velocity distribution of flow in the cyclone. The authors took advantage of RSM turbulence model of software FLUENT to calculate the velocity distribution. Relationship between particles separation and double-layer rotating flow can be obtained based on the simulation results, which can also provide basis for the improvement of structure design and separation performance.


2021 ◽  
Vol 11 ◽  
Author(s):  
Liang He ◽  
Weiwei Sun ◽  
Xiang Chen ◽  
Liqi Han ◽  
Jincai Li ◽  
...  

Increased plant density markedly affects canopy morphophysiological activities and crop productivity. This study aims to model maize canopy final morphology under increased interplant competition by revising a functional–structural plant model, i.e., ADEL-Maize. A 2-year field experiment was conducted at Mengcheng, Anhui Province, China, in 2016 and 2018. A randomized complete block design of five plant densities (PDs), i.e., 4.5, 6, 7.5, 9, and 15 plants m–2, with three replications was applied using a hybrid, i.e., Zhengdan 958. Canopy morphology at different PDs was measured with destructive samplings when maize canopy was fully expanded. The relationship of changes of organ morphology in relation to increased plant density was analyzed based on 2016 data. The ADEL-Maize was first calibrated for the hybrid at 4.5 plants m–2 and then revised by introducing relationships identified from 2016 data, followed by independent validation with 2018 field data. A heatmap visualization was shown to clearly illustrate the effects of increased plant density on final morphology of laminae, sheaths, and internodes. The logarithmic + linear equations were found to fit changes for the organ size versus increased plant density for phytomers excluding ear position or linear equations for the phytomer at ear position based on 2016 field data. The revision was then further tested independently by having achieved satisfactory agreements between the simulations and observations in canopy size under different PDs with 2018 field data. In conclusion, this study has characterized the relationship between canopy morphology and increased interplant competition for use in the ADEL-Maize and realized the simulations of final size of laminae, sheaths, and internodes, as affected by increased plant density, laying a foundation to test an ideotype for maize withstanding high interplant competition.


2021 ◽  
Vol 30 (1) ◽  
Author(s):  
Tuan Minh Tran ◽  
Quang Huy Nguyen

In recent years, experimental and numerical researches on the effect of blasting pressure on the stability of existing tunnels was widely obtained. However, the effect of the blasting pressure during excavation a new tunnel or expansion old tunnels on an existing tunnel has disadvantages and still unclear. Some researches were carried out to study the relationship of the observed Peak Particle Velocity (PPV) on the lining areas along the existing tunnel direction, due to either the lack of in situ test data or the difficulty in conducting field tests, particularly for tunnels that are usually old and vulnerable after several decades of service. This paper introduces using numerical methods with the field data investigations on the effect of the blasting in a new tunnel on the surrounding rock mass and on the existing tunnel. The research results show that not only predicting the tunnel lining damage zone under the impact of blast loads but also determination peak maximum of explosion at the same time at the surface of tunnel working.


1964 ◽  
Vol 17 (1) ◽  
pp. 57-65 ◽  
Author(s):  
V. H. King ◽  
W. E. J. Groves

This paper first considers the characteristics of the supersonic transport aircraft (S.S.T.) as established by various international authorities and, on the basis of these characteristics, endeavours to deduce the operational requirements for a navigation system. An indication is then given of the extent to which low frequency radio aids (such as Decca and Harco) can meet these requirements in the subsonic, transition and supersonic flight regimes, whilst discussing the relationship of these ground-based systems to self-contained aids. The paper was presented, in a fuller version, at the meeting of the Deutsche Gesselschaft fiir Ortung und Navigation held in Berlin, 22–7 April 1963.


1993 ◽  
Vol 39 (132) ◽  
pp. 323-326 ◽  
Author(s):  
D. M. McClung ◽  
Richard L. Armstrong

AbstractThe relationship of glacier response due to mass-balance changes is of fundamental importance when climate variations are to be understood. In this paper, two aspects of the problem are analyzed from field data: (1) advance/retreat of the glacier terminus due to changes in mass balance, and (2) cross-correlation of mass-balance data from two glaciers in the same climate zone. The results show: (1) the terminus can respond quickly in accordance with expected minimum time-scale, and (2) two glaciers in the same general climate zone may have very different yearly mass balance and advance/retreat behaviour. This latter result indicates the importance of local climate variations.


1993 ◽  
Vol 39 (132) ◽  
pp. 323-326 ◽  
Author(s):  
D. M. McClung ◽  
Richard L. Armstrong

AbstractThe relationship of glacier response due to mass-balance changes is of fundamental importance when climate variations are to be understood. In this paper, two aspects of the problem are analyzed from field data: (1) advance/retreat of the glacier terminus due to changes in mass balance, and (2) cross-correlation of mass-balance data from two glaciers in the same climate zone. The results show: (1) the terminus can respond quickly in accordance with expected minimum time-scale, and (2) two glaciers in the same general climate zone may have very different yearly mass balance and advance/retreat behaviour. This latter result indicates the importance of local climate variations.


2021 ◽  
Vol 11 (20) ◽  
pp. 9572
Author(s):  
Yongjian Zhang ◽  
Lin Wang ◽  
Guo Wei ◽  
Chunfeng Gao

Aircraft flying the trans-arctic routes usually apply inertial navigation mechanization in two different navigation frames, e.g., the local geographic frame and the grid frame. However, this change of navigation frame will cause filter overshoot and error discontinuity. To solve this problem, taking the inertial navigation system/global navigation satellite system (INS/GNSS) integrated navigation system as an example, an integrated navigation method based on covariance transformation is proposed. The relationship of the system error state between different navigation frames is deduced as a means to accurately convert the Kalman filter’s covariance matrix. The experiment and semi-physical simulation results show that the presented covariance transformation algorithm can effectively solve the filter overshoot and error discontinuity caused by the change of navigation frame. Compared with non-covariance transformation, the system state error is thereby reduced significantly.


2021 ◽  
pp. 144078332110442
Author(s):  
Val Colic-Peisker ◽  
Andy Peisker

This article explores the relationship of residential concentrations of non-Anglophone migrants with socio-economic disadvantage at the suburb (SA2) level. We look at two main Australian gateway cities, Sydney and Melbourne. We use the ‘person-counts’ of the latest available (2016) Australian Census data, matching them with the socio-economic data provided by the Australian Bureau of Statistics ‘socio-economic indexes for areas’ (SEIFA). Our analysis shows that despite decades of careful filtering of migrants for skills and language, socio-economic disadvantage in migrant concentrations persists in the main gateway cities, being more pronounced in Melbourne than in Sydney. The article employs an original quantitative analysis in order to advance the understanding of relationship between ethnicity, socio-economic position and residential location. We seek to contribute to the ongoing scholarly and policy debate about migrant concentration areas in large immigrant-receiving cities.


The relationship of rain flow is needed to get an accurate peak discharge and volume value. This value is require so that the analysis of hydrological problems produces an approach that is closer to reality in the watershed. Calibration and validation have been carried out in the form of statistical steps. The reliability of calibration with statistics in certain sections provides less accurate results. HSS snyder calculation uses the parameters Cp and Ct. These two parameters cannot be determined with certainty. Therefore, the parameters Cp and Ct need to be optimized to get a more reliable value. Calculation of the relationship of rain flow using the Snyder synthetic hydrograph method was chosen because it was able to be used if the watershed characteristics data were limited. Hydrograph calibration is commonly used with standard deviation statistics between the two data. Ant colony optimization was performed so that the calculation results are even better so that it gives a true picture of the hydrological phenomenon in an area. Field data calibration with the optimization of the Snyder hydrograph provides better R and SD values than the HSS Snyder without optimization. The optimization result of the Snyder hydrograph is Q p = 0.44 . A / t p .


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