Influence of hydro-meteorological conditions on operational parameters of panamax size vessels

2016 ◽  
Vol 31 ◽  
pp. 130-137
Author(s):  
Tadeusz Pastusiak
2013 ◽  
Vol 6 (1) ◽  
pp. 43-68
Author(s):  
K. Du ◽  
K. Wang ◽  
P. Shi ◽  
Y. Wang

Abstract. A digital optical method "DOM-Vis" was developed to measure atmospheric visibility. In this method, two digital pictures were taken of the same target at two different distances along the same straight line. The pictures were analyzed to determine the optical contrasts between the target and its sky background, and subsequently, visibility is calculated. A light transfer scheme for DOM-Vis was delineated, based upon which, algorithms were developed for both daytime and nighttime scenarios. A series of field tests were carried out under different weather and meteorological conditions to study the impacts of such operational parameters as exposure, optical zoom, distance between the two camera locations, and distance of the target. This method was validated by comparing the DOM-Vis results with those measured using a co-located Vaisala® visibility meter. The visibility under which this study was carried out ranged from to 1 km to 20 km. This digital photography based method possesses a number of advantages compared with traditional methods. Pre-calibration of the detector with a visibility meter is not required. In addition, the application of DOM-Vis is independent of several factors like the exact distance of the target and several camera setting parameters. These features make DOM-Vis more adaptive under a variety of field conditions.


2013 ◽  
Vol 6 (8) ◽  
pp. 2121-2130 ◽  
Author(s):  
K. Du ◽  
K. Wang ◽  
P. Shi ◽  
Y. Wang

Abstract. A digital optical method "DOM-Vis" was developed to measure atmospheric visibility. In this method, two digital pictures were taken of the same target at two different distances along the same straight line. The pictures were analyzed to determine the optical contrasts between the target and its sky background and, subsequently, visibility is calculated. A light transfer scheme for DOM-Vis was delineated, based upon which algorithms were developed for both daytime and nighttime scenarios. A series of field tests were carried out under different weather and meteorological conditions to study the impacts of such operational parameters as exposure, optical zoom, distance between the two camera locations, and distance of the target. This method was validated by comparing the DOM-Vis results with those measured using a co-located Vaisala® visibility meter. The visibility under which this study was carried out ranged from 1 to 20 km. This digital-photography-based method possesses a number of advantages compared with traditional methods. Pre-calibration of the detector with a visibility meter is not required. In addition, the application of DOM-Vis is independent of several factors like the exact distance of the target and several camera setting parameters. These features make DOM-Vis more adaptive under a variety of field conditions.


Author(s):  
David C Joy

The electron source is the most important component of the Scanning electron microscope (SEM) since it is this which will determine the overall performance of the machine. The gun performance can be described in terms of quantities such as its brightness, its source size, its energy spread, and its stability and, depending on the chosen application, any of these factors may be the most significant one. The task of the electron gun in an SEM is, in fact, particularly difficult because of the very wide range of operational parameters that may be required e.g a variation in probe size of from a few angstroms to a few microns, and a probe current which may go from less than a pico-amp to more than a microamp. This wide range of operating parameters makes the choice of the optimum source for scanning microscopy a difficult decision.Historically, the first step up from the sealed glass tube ‘cathode ray generator’ was the simple, diode, tungsten thermionic emitter.


Author(s):  
A.I. Belenkov ◽  
◽  
S.V. Zhelezova ◽  
D.V. Bereza

The article considers the issues of the influence of the main tillage on the yield of crops of grain-tilled crop rotation: vetch-oat mixture - winter wheat - potatoes - barley. It was found that in addition to the reception of soil cultivation, the productivity of agrocenoses was also influenced by meteorological conditions.


2010 ◽  
Vol 9 (10) ◽  
pp. 1451-1457 ◽  
Author(s):  
Corina-Petronela Musteret ◽  
Daniela Cailean ◽  
George Barjoveanu ◽  
Carmen Teodosiu

Author(s):  
А. Yu. Izmaylov ◽  
Ya. P. Lobachevskiy ◽  
V. К. Khoroshenkov ◽  
N. Т. Goncharov ◽  
S. E. Lonin ◽  
...  

The introduction of information and digital technologies that support and support all technological processes in the field is an urgent need for the development and implementation of such technology. An organisationally complex and financially intensive project is necessary because of the wide variety of economic entities that differ in the size of production, forms of ownership and socio-economic conditions of production. Automated information control system for mobile units agricultural enterprise provides those-Niko-economic performance, optimum capacity utilization through the use of timely and reliable information on technology. Machine and tractor aggregates are appertained as control objects with variable structure, which is explained by possibility of the system formation from tractor or field machines mobile units with various purposes: tillable, cultivatable, sowing, harvesting and etc. This MTA feature was determined creation of digital control systems of two groups of automatic control and management of the basic energy and operational parameters: tractors, machines and vehicles as part of MTA. To the first group are appertained the automatic control system of tractor motor component loading, motion speed, frictional sliding. To the second group – automatic regulation system of operating depth, seed rate, treatment of liquid combined fertilizers and crop protection agents, filling and driving of various MTA. Novelty of researches consists in methodology of the organization of the centralized control and management of various technological processes at carrying out field works.


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