bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of polyphenolics in extracts of Potentilla species by high‐performance thin‐layer chromatography photodensitometry method
Authors: Tomczyk Michał , Bazylko Agnieszka , Staszewska Anna
Published: October 2009

Introduction – Separation of polyphenolics in different plant materials using high‐performance thin‐layer chromatography (HPTLC) represents an effective method for their detection and quantification.

Objective – To develop a simple, specific, precise, sensitive and accurate method for the simultaneous quantification of tiliroside (TRS), methyl brevifolincarboxylate (MBR) and ellagic acid (EA) in a plant extract using the HPTLC‐photodensitometry method.

Methodology – Aerial parts of the selected Potentilla species, P. anserina, P. erecta, P. grandiflora and P. nepalensis var. ‘Miss Willmott’, were extracted with methanol. After solvent evaporation, the methanolic extracts were diluted with water and successively partitioned between chloroform and then diethyl ether. The diethyl ether extracts from each sample were used for quantification. The analyses were performed on HPTLC precoated silica gel 60F254 plates with toluene–ethyl formate–formic acid (6 : 4 : 1 v/v/v) as the mobile phase (distance of 7.5 cm). Densitometric detections of TRS, MBR and EA were performed at 320, 287 and 280 nm, respectively. The amounts of these compounds were calculated using the regression equations of the calibration curves, which were linear within a range of 0.05–0.5 μg/spot (R2 = 0.9957) for TRS, 0.05–0.525 μg/spot (R2 = 0.9965) for MBR and 0.0525–0.5 μg/spot (R2 = 0.9998) for EA.

Results – The amounts of marker compounds measured by the method developed are expressed in mg/g of dry extracts. TRS ranged from 20.3 ± 0.3 mg/g for P. erecta herbs to 197.7 ± 2.9 mg/g for P. grandiflora herbs; MBR ranged from 5.0 ± 0.6 mg/g for P. erecta herbs to 68.5 ± 3.4 mg/g for P. nepalensis flowers; and EA ranged from 24.0 ± 0.6 mg/g for P. erecta herbs to 216.2 ± 3.2 mg/g for P. anserina leaves.

Conclusion – The proposed method was found to be relatively simple, specific, precise, sensitive and accurate and may be used for the routine assay of simultaneous determination of TRS, MBR and EA in other extracts and phytomedicines containing Potentilla species. Copyright © 2009 John Wiley & Sons, Ltd.
Types and treatment of pediatric sleep disturbances
Authors: Hamilton Gloria J.
Published: October 2009

This article provides an overview of pediatric sleep disturbances with emphases on types and treatments. Relationships between sleep disorders and comorbid conditions function to exacerbate and maintain both disorders. An estimated 20% of teenagers experience chronic partial sleep deprivation, resulting in problems with memory, attention, and behavior control. Treatment of choice for chronic partial sleep deprivation involves a comprehensive approach to regularizing the adolescent's sleep–wake schedule. The American Academy of Pediatrics (AAP) calls into question the validity of upward trends in prescribing for children and adolescents who report sleep problems. The AAP has issued a consensus statement on prescribing hypnotics to children and adolescents, arguing that further clinical trials are necessary to determine appropriate pediatric dosages. The AAP recommends that pediatricians educate families about good sleep practices and behavioral interventions. © 2009 Wiley Periodicals, Inc.
Mn configuration in III‐V semiconductors and its influence on electric transport and semiconductor magnetism
Authors: Wolos Agnieszka , Piersa Miroslaw , Strzelecka Grazyna , Korona Krzysztof P. , Hruban Andrzej , Kaminska Maria
Published: October 2009

GaAs and GaP doped with Mn at wide range of concentrations were studied and compared to literature data of InP and nitrides, GaN and AlN, in aim to understand the mechanism of ferromagnetism observed in some of them. Doping with a moderate Mn concentrations resulted in similar features of electric transport in these compounds, that is p‐type conductivity in host crystal valence band activated with energy related to the ionization energy of Mn acceptor at high temperature and hopping conductance in Mn impurity band dominating at low temperatures. From the magnitude of hopping conductance it was possible to determine Mn configuration, which occurred to be Mn2+(d5) with a bound hole on it, with different localization radius decreasing systematically in a series from GaAs through InP down to GaP and achieving full localization resulting in Mn3+(d4) configuration in wide band gap nitrides, GaN and AlN. A critical concentration of Mn for metal‐insulator transition related to full overlap of Mn‐bound hole wave functions could be calculated as equal to 3.6 × 1020 cm–3 in GaAs, 2.5 × 1021 cm–3 in InP and 3.7 × 1022 cm–3 in GaP, where the latter one corresponds to above 100 at.%. Similarly to GaP, metal‐insulator transition for GaN and AlN doped with Mn cannot be achieved even for 100% of Mn concentration. In GaAs doped with Mn on the level of about 2.8 × 1019 cm–3 split Mn impurity band is formed. Conductivity in the band at this Mn concentration is characterized by high mobility, comparable in magnitude to the mobility in GaAs valence band. Ferromagnetism of GaAs with high Mn concentration (> 1.1 ‐ 1.6 at.%) occurs in samples being on the metallic side of metal‐insulator transition what means that a mediating center in ferromagnetic ordering of Mn centers is totally unlocalized hole. This mechanism is difficult to realize in other studied III‐V compounds because of higher localization of Mn‐bound holes. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Distribution of relaxation times of relaxors: comparison with dipolar glasses
Authors: Banys Juras , Grigalaitis Robertas , Mikonis Andrejus , Macutkevic Jan , Keburis Povilas
Published: October 2009

In the present publication we report the results of dielectric spectroscopy investigations of two classes of materials – relaxor and dipolar glasses. As model relaxor was chosen (Pb1–xLax)(ZryTi1–y)O3 (PLZT 100(x/y/1–y)). The real distribution function of the relaxation times f (τ) of the relaxor ferroelectric ceramics PLZT 8/65/35 and 9.5/65/35 was calculated from the dielectric measurements results in the wide frequency range (101–1012 Hz). Below the Burns temperature TB ≅ 620 K, when the clusters begin to appear on cooling, the distribution function of the relaxation times is symmetrically shaped. On cooling the dispersion and loss spectra strongly broaden and slow down, the f (τ) function becomes asymmetrically shaped and the second maximum appears. The width of the f (τ) function was calculated at different temperatures. The longest relaxation times diverge according to the Vogel‐Fulcher law with the freezing temperature 299 K and 252 K for the 8/65/35 and 9.5/65/35 samples, respectively. The shortest relaxation time is about 10–12 s and it remains almost temperature independent. Similar behaviour was observed in dipolar glasses betaine phosphate betaine phosphite (BP/BPI). Much more information was obtained from two dimensional distribution of the relaxation times. This confirmed Meyer–Neldel law in relaxors and dipolar glasses. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computational insights into halogen bonding between PCl contact and several electron donors
Authors: Xu Lin , Zou Jian‐Wei , Yu Qing‐Sen , Sang Peng
Published: October 2009

In this work, computations of density functional theory (DFT) have been carried out to investigate the interactions between the PCl unit of hexachlorocyclotriphosphazene and several common electron donors. Such small systems are selected to explore the potential P‐bound halogen bonding interactions within polymeric structure and supramolecules. In all cases, the intermolecular distances are shown to be equal to or below sums of van der Waals radii of the atoms involved. Halogen bonding energies, calculated at B971/6‐311+G(d,p), span over a relatively lager range, from −0.95 to −95.30 kcal/mol, which intimate that the interactions are comparable to, or even partly prevail over, the conventional hydrogen bonding. For the charge‐assisted systems, calculations show that these systems can result in much stronger halogen bonding than the corresponding neutral ones. The results agree well with those of natural population analysis (NPA). Finally, the theory of atoms in molecules (AIM) was applied to provide more insight into the nature of these interactions. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Neighbourhood density and social sustainability in cities of developing countries
Authors: Dave Seema
Published: October 2009

Within the concept of sustainable development, there is very little known about social impacts and levels of acceptability of compact urban form in the context of cities of developing countries. Social sustainability of these cities in developing countries might have a huge impact on the overall global sustainability, considering their large population size and high economic growth. This paper provides new empirical evidence from 11 case study neighbourhoods of different densities and built forms within the Mumbai Metropolitan Region to evaluate the relationship between social sustainability and urban densities. In doing so, impacts of both physical and perceived density on selected aspects of social sustainability in the context of Mumbai were examined. The findings suggest that, on social aspects of sustainability, higher household density and population density have no negative impacts. However, importantly, most of the negative associations of density were related to the perceptions of density, and therefore the built form, layout, design and amount of mix of uses as well as socio‐demographic variables such as family income and location were found to have an important role in achieving social sustainability. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Basic concepts and performance measures in prediction of collapse of buildings under earthquake ground motions
Authors: Zareian Farzin , Krawinkler Helmut , Ibarra Luis , Lignos Dimitrios
Published: October 2009

This paper summarizes collapse performance measures and the probabilistic basis for their development to assist in understanding of collapse behaviour of buildings and implementation of performance objectives in design and evaluation of buildings for collapse safety. Collapse in this context is defined as the loss of lateral load‐resisting capability of a building's structural system caused by ground shaking. Estimation of collapse performance requires the relation between a ground motion intensity measure (IM) and the probability of collapse, denoted as collapse fragility curve, and the relation between the same ground motion IM and the seismic hazard for the building, denoted as seismic hazard curve. Two methods for estimating the collapse fragility curve of a building are discussed: the EDP‐based approach and the IM‐based approach. In both approaches, collapse is associated with a scalar ground motion IM and is obtained by utilizing Incremental Dynamic Analysis. The collapse performance criteria presented in this paper are compared with the collapse performance criteria recommended in the SAC/Federal Emergency Management Agency guidelines. An eight‐storey moment‐resisting frame case study is used to compare the estimates of collapse performance of various approaches discussed in this paper. Copyright © 2009 John Wiley & Sons, Ltd.
Discrete‐time ${\cal H}_{\rm 2}$ output tracking control of wireless networked control systems with Markov communication models
Authors: Yu Bo , Shi Yang , Lin Yang
Published: October 2009

This paper considers the discrete‐time${\cal H}_2$output tracking control of wireless networked control systems (NCSs) where the time delays are modeled as Markov chains. Output tracking control can find many applications in industry. In order to reduce the conservativeness and achieve better performance, the designed state feedback controller is dependent on available sensor‐to‐controller and controller‐to‐actuator delays. Then, the formulated closed‐loop system is a special jump linear system governed by interdependent parameters of Markov chains and the condition for stochastic stability is proposed. By generalization of the${\cal H}_2$norm definition, new relation of the${\cal H}_2$norm for the special system is derived in terms of state space form. The condition of a set of linear matrix inequalities (LMIs) with nonconvex constraints is given to solve the${\cal H}_2$output tracking control problem. Simulation examples are provided to illustrate the effectiveness of the method. Copyright © 2009 John Wiley & Sons, Ltd.
A novel communication infrastructure for emergency management: the In.Sy.Eme. vision
Authors: Fantacci Romano , Marabissi Dania , Tarchi Daniele
Published: October 2009

Wireless communications have achieved a great attention during the last decades due to the easy implementation, possibility of delivering multimedia services to rural communities, suitability for public safety and emergency communications. In particular, a wireless network designed for an emergency scenario seems to be the best solution to manage all the phases of an emergency situation, from the prevention to the post‐emergency management. This paper discusses the main features of a such wireless network aiming to interconnect several heterogeneous systems and providing multimedia access to groups of people involved in emergency operations as foreseen by the In.Sy.Eme. (Integrated System for Emergency) project. In particular, the focus here will be on a communication infrastructure able to efficiently support a pervasive high performance distributed elaboration structure based on the Next Generation Grid principle. Main scope of the proposed system is that of allowing functional integration of new technologies with actual or off‐the‐shelf technologies to provide fast responses to any emergency situations and efficient use of all available resources. Copyright © 2009 John Wiley & Sons, Ltd.
Differential Expression of Lipid Metabolism Related Genes in Porcine Muscle Tissue Leading to Different Intramuscular Fat Deposition
Authors: Zhao S. M. , Ren L. J. , Chen L. , Zhang X. , Cheng M. L. , Li W. Z. , Zhang Y. Y. , Gao S. Z.
Published: October 2009

Intramuscular fat (IMF) content affects meat quality and varies in different pig breeds. However, the underlying mechanisms of different IMF depositions in different genetic backgrounds of pigs have not been fully elucidated as yet. Lipid metabolism theoretically contributes to the variation of IMF content. The expression levels of genes and proteins as well as enzyme activities implicated in muscle lipid metabolism were investigated, which included lipogenetic genes (SREBP‐1c and FAS), fatty acid transporting genes (H‐FABP and A‐FABP), fatty acid oxidative gene (CPT‐1B) and lipolytic genes (ATGL and HSL) as well as the desaturated fatty acid gene (SCD). Longissimus muscle samples were collected from fatty Wujin pigs and lean Landrace pigs. Results showed that the average daily gain of Wujin pigs was lower than that of Landrace pigs. Wujin pigs had greater adipocyte diameter, IMF content and PUFA percentage than that of Landrace pigs. Compared with Landrace pigs, Wujin pigs exhibited higher expression levels, both in mRNA and protein, of FAS, SREBP‐1c, SCD, A‐FABP and H‐FABP genes and lower expression levels of CPT‐1B, HSL and ATGL genes. Overall, Wujin pigs possessed higher mRNA abundance, protein expression or enzyme activities of anabolism, fatty acid transportation and desaturation, and lower catabolism. Therefore, the mechanism of higher IMF content in fatty pigs may be due to the higher capacity of lipogenesis and fatty acid transportation and the lower capacity of lipolysis.
ER exit sites – Localization and control of COPII vesicle formation
Authors: Budnik Annika , Stephens David J.
Published: October 2009

The first membrane trafficking step in the biosynthetic secretory pathway, the export of proteins and lipids from the endoplasmic reticulum (ER), is mediated by COPII‐coated vesicles. In mammalian cells, COPII vesicle budding occurs at specialized sites on the ER, the so‐called transitional ER (tER). Here, we discuss aspects of the formation and maintenance of these sites, the mechanisms by which cargo becomes segregated within them, and the propagation of ER exit sites (ERES) during cell division. All of these features are inherently linked to the formation, maintenance and function of the Golgi apparatus underlining the importance of ERES to Golgi function and more widely in terms of intracellular organization and cellular function.
Genomic analysis of a novel integrative conjugative element in Vibrio cholerae
Authors: Taviani Elisa , Grim Christopher J. , Chun Jongsik , Huq Anwar , Colwell R.R.
Published: October 2009

Integrative conjugative elements (ICEs) are a class of self‐transmissible mobile elements that mediate horizontal gene transfer in bacteria, and play an important role in bacterial evolution. Since 1992, ICEs of the SXT/R391 family have been found to be widely distributed among Vibrio cholerae strains isolated in Asian countries. Here we describe ICEVchB33, an ICE found in the genomes of two V. cholerae O1 Eltor strains, one isolated in India, 1994, and the other from Mozambique, 2004. ICEVchB33 revealed a new genetic organization, different from other ICEs of the SXT/R391 family, demonstrating the genomic plasticity of these elements.
Inhibition of aldose reductase by dietary antioxidant curcumin: Mechanism of inhibition, specificity and significance
Authors: Muthenna P. , Suryanarayana P. , Gunda Shravan K. , Petrash J. Mark , Reddy G. Bhanuprakash
Published: October 2009

Accumulation of intracellular sorbitol due to increased aldose reductase (ALR2) activity has been implicated in the development of various secondary complications of diabetes. In this study we show that curcumin inhibits ALR2 with an IC50 of 10 μM in a non‐competitive manner, but is a poor inhibitor of closely‐related members of the aldo‐keto reductase superfamily, particularly aldehyde reductase. Results from molecular docking studies are consistent with the pattern of inhibition of ALR2 by curcumin and its specificity. Moreover, curcumin is able to suppress sorbitol accumulation in human erythrocytes under high glucose conditions, demonstrating an in vivo potential of curcumin to prevent sorbitol accumulation. These results suggest that curcumin holds promise as an agent to prevent or treat diabetic complications.
Catagenesis of organic matter at the top and base of the Jurassic complex in the West Siberian megabasin
Authors: Kontorovich A.E. , Fomin A.N. , Krasavchikov V.O. , Istomin A.V.
Published: October 2009

Thermal maturation for the top and base of the Jurassic in the West Siberian megabasin was modeled on the basis of the vitrinite reflectance (Rvt0) data using mathematical modeling and computer simulations. The values of thermal maturation are found to vary within substages PC3–MC32 for the top (or being equivalent to PC3-MC12 on the periphery and southern part of the basin, or to MC2-MC32 in the north) and PC3-AC3 for the base of the Jurassic (or being equivalent to PC3-MC2 on the periphery and southern part of the basin or MC31-AC3 in the north). Thermal maturity levels of the Jurassic in West Siberia are controlled by depths of burial and peak temperatures which the source rocks were subjected to during this period. The situation is further complicated by high heat flows superimposed on the regional background, which are observed in deep fault zones and in the proximity of numerous igneous bodies.
REAL HYPERSURFACES WITH CYCLIC-PARALLEL STRUCTURE JACOBI OPERATORS IN A NONFLAT COMPLEX SPACE FORM
Authors: KI U-HANG , KURIHARA HIROYUKI
Published: October 2009

It is known that there are no real hypersurfaces with parallel structure Jacobi operators in a nonflat complex space form. In this paper, we classify real hypersurfaces in a nonflat complex space form whose structure Jacobi operator is cyclic-parallel.
RE-CONCEPTUALIZING THE RIGHT OF SILENCE AS AN EFFECTIVE FAIR TRIAL STANDARD
Authors: Jackson John
Published: October 2009

As the European Court of Human Rights has come to qualify the privilege against self-incrimination and the right of silence in recent decisions, this article argues that the Court has failed to provide a convincing rationale for these rights. It is claimed that within the criminal process the right of silence should be distinguished from the privilege against self-incrimination and given enhanced effect in order to uphold the protective and participatory rights of the defence which come into play when a suspect is called upon to answer criminal allegations.
Laser Airborne Depth Sounding in Australia
Authors: Penny M. F. , Abbot R. H. , Phillips D. M. , Billard B. , Rees D. , Faulkner D. W. , Cartwright D. G. , Woodcock B. , Perry G. J. , Wilsen P. J. , Richards J.
Published: October 2009

Australia, with its large continental shelf, requires faster and more economic methods of conducting hydrographic survey. Backed by the Royal Australian Navy an experimental programme to investigate airborne laser methods was commenced in the mid 1970s and completed in 1984. This programme demonstrated that airborne laser depth sounding can be used effectively in Australian coastal waters. This paper reviews the achievements of the experimental programme and describes some features of LADS, a ‘Laser Airborne Depth Sounder’ planned for operational use by the RAN Hydrographic Service. The paper was presented at the Congress of the International Association of Institutes of Navigation, Tokyo, 1–5 October 1985.
The Backstaff and the Determination of Latitude at Sea in the Seventeenth Century
Authors: Forty Gerald
Published: October 2009

In a previous paper the writer considered the problems of establishing latitude at sea in the sixteenth century and in part based his conclusions on the results of experiments made with modern replicas of the quadrant, the mariner's astrolabe and in particular the cross-staff, these being the instruments in use at the time. Reference was made to the backstaff or Davis quadrant which, though first described by John Davis in its simplest form in 1595 was not in effective use in its final version until well into the seventeenth century. It remained, together with the cross-staff, the principal altitude-measuring instrument in use at sea until the introduction of instruments of reflection in the eighteenth century and indeed continued in use long after that time, no doubt because it was cheaper than the new instruments, but perhaps also in part because of the ingrained conservatism of seafarers. The name ‘backstaff’ can be used generically to refer to all those instruments with which the observer turns his back on the Sun (e.g. the Gunter's bow), but they all post-dated and derived in concept from the Davis quadrant, which remained the most common in England and elsewhere. (The French knew it as le quartier anglais.) It is in this sense that the term is used here.
Digital Colour Map Units for Land Navigation
Authors: Halliwell D.
Published: October 2009

Large numbers of land vehicles, ranging from complex and expensive military vehicles to private cars, are fitted with, or are considering fitting, navigation systems from the range of systems available. Common requirements for all applications are that the navigation system should contribute to increased operational performance and, at the same time, reduce the crew's workload. A most important element of the system is the operator's display.
Colour Dependence and Surplus Information in Airport Visual Aids During VFR Operations
Authors: McKelvey Robert K.
Published: October 2009

Airport visual aids are examined for failure of transfer from chromatic (i.e. normal) to achromatic viewing situations which would suggest a non-redundant use of colour, and for their information value during VFR (visual flight rule) operations as a function of the airport operating classification for which they were designed. From photographs taken under visual meteorological conditions at night, slide sequences representing the visual presentations associated with aircraft movements during taxi-out, take-off, approach and landing operations were prepared and shown to experienced pilots in a time-stressed forced-choice procedure. The results suggest that among displays in current use only the signal light from the control tower is completely colour-dependent. Also, the information value of some taxi-way and approach lighting components might be questioned. An argument is presented for a ‘building-blocks’ review of the airport visual-aids system that could in some cases result in improved relationships between economy of display content and information value.
The Automatic Detection of Real-Life Ship Encounters
Authors: Curtis Robert G. , Goodwin Elisabeth M. , Konyn Mark
Published: October 2009

There are now radar installations which track ships automatically, and these radars can provide the researcher with statistics on collision-avoidance manoeuvres. The extraction, by hand, is laborious and time consuming. This paper describes a mathematical model which automatically detects collision-avoidance manoeuvres. The model operates on an adaption of the Range to Domain Over Range Rate (RDRR) principle, which enables ships to be identified for analysis shortly before they are expected to initiate a collision-avoidance manoeuvre. The model has been computerized and results presented.
Factors Affecting Shipping Losses by Collision and Wreck
Authors: Cockcroft A. N.
Published: October 2009

The annual total losses of trading ships as a result of collision and wreck were considered in a previous paper for the purposes of comparing the safety records of different flag groups. Losses up to the year 1979 were included in the tables. In order to assess whether there has been an improvement, the losses for the 5-year period 1980–4 will now be considered and compared with losses in previous years.
The Use of Differential Navstar GPS to Aid the Visually Impaired
Authors: Nolan Thomas P. , Carpenter Max H.
Published: October 2009

The ability of visually impaired individuals, especially when blind, to locate themselves in an urban or rural environment with respect to road intersections, prominent landmarks, etc. has always been a serious problem. In addition, and of equal importance, is the inability to communicate their location to a central control facility in the event of their needing any additional assistance.

With the advent of high accuracy global positioning many applications, which heretofore had been considered highly futuristic and discussed only in the most tentative terms, are now being researched. One such application is the use of differential Navstar GPS and its capability as an aid to the visually impaired. The concept envisions a small device that can be worn by the user. This device will have the means for providing Navstar GPS phase information accurate enough to be converted to a specific street location. Inherent in the concept is means by which the users can be instantly apprised of their location and/or can communicate with a central location for other purposes.

To establish feasibility of such an application, it was necessary to understand the limitations of Navstar GPS. In particular those that may result from its use in an urban environment. Accuracies of the Navstar GPS system tend to depend on the sophistication of the receiver to be used. At the time there was some question as to future developments of a small enough package for the intended use. Along with this was the question of the suitability of differential positioning for increased accuracy. This article deals with the initial field tests that were run and the conclusions drawn from this work.

Similar work was previously accomplished in 1985 by the US Department of Transportation, Transportation Systems Center. The referenced effort included both the use of Navstar GPS as well as Loran-C which our effort did not but did confirm a number of our findings relating to the limitations of Navstar GPS in an urban environment and attenuation in the presence of foliage, it did not centre on differential Navstar GPS as did our work.
Navigation and International Cooperation
Authors: Prunieras Jean
Published: October 2009

The content of this paper is based on my own experience of international cooperation in the field of navigation. For this reason, the presentation is divided into three parts and these are related to the International Association of Lighthouse Authorities (IALA) and to the International Association of Institutes of Navigation (IAIN).
The Global Maritime Distress and Safety System: Basic Concept and Functions
Authors: Kent P. E.
Published: October 2009

Safety of life at sea and assistance to persons in distress are matters of great importance to seafarers, shipowners and maritime administrations and have been addressed by the International Maritime Organization (IMO) since its foundation.
The European ATC System: Constraints and Traffic Management
Authors: Brooker Peter
Published: October 2009

This, and the following three papers were presented at the Royal Institute of Navigation meeting ‘Management of Air Traffic Flow in Europe' on 15 November 1989.

One of the growth industries in Europe is the production of articles in newspapers and programmes on radio and television which deal with European air traffic control. They usually have titles like, ‘The Crisis in ATC’, or ‘European Air Traffic Meltdown’. Jane's Airport Review, in October 1989, had an article entitled ‘Wanted: One ATC System for Europe’.
Do Humans Possess a Latent Sense of Orientation?
Authors: Campion Mary
Published: October 2009

For a long time it has been accepted as fact that at least certain animals, such as birds and honey bees, have an in-built sense of orientation which enables them to find their way home. Less well-known examples occur among the molluscs and amphibians.
An Analysis of Visual Watchkeeping
Authors: Taylor Donald H.
Published: October 2009

Ships' bridge watchkeeping, although the prime task of the officer of the watch, makes very low task demands in terms of information processing and required speed of response compared to most other vigilance tasks. Consequently, performance of the visual lookout task is difficult to describe and evaluate systematically. Results from an on-board observational study show that lookout lapse periods can be economically described by simple mathematical models, which assist in comparison and evaluation of task performance.
A Fully Automatic Berthing Test Using the Training Ship Shioji Maru
Authors: Ohtsu Kohei , Takai Tadao , Yoshihisa Hideaki
Published: October 2009

In this paper, the authors discuss a fully automatic berthing system and actual tests using a small training ship, Shioji Maru. The ship is about 440 gross tonnage and furnished with a controllable pitch propeller, a bow thruster and a stern thruster to which a computer can easily be linked. The system developed is composed of an electro-optical position measuring system and the computer software necessary for manoeuvring the ship.

The electro-optical position measuring system can measure a distance between the ship and a target on a berth within 4 cm accuracy and cover an area out to about 100 m range. The manoeuvring is divided into two stages. The first one is from a start line to a transition point off the final berth. At this point, the ship must be stopped in an alongside attitude to the berth. In the second stage, the ship is pushed by the thrusters in an athwartships direction towards the berth and the final speed at the berth must be limited to within 0.5 ms. The computer software generates an appropriate strategy following an approach line which has been determined in advance.

According to the actual tests under slightly rough sea conditions, the system could manoeuvre the ship along the approach line by a direct path and maintain her final speed within the predetermined limit.
Air Navigation Systems Chapter 4. Hyperbolic Airborne Radio Navigation Aids – A Navigator's View of their History and Development
Authors: Blanchard W. F.
Published: October 2009

This paper is the fourth chapter of a series on Air Navigation Systems during theperiod from the early oceanic flights and the inception of commercial aviation to the introduction of INS in civil aircraft. Comments on the content of the paper would be welcomed by the author and the editor.
Loran-C System Trials
Authors: Ward N.
Published: October 2009

In 1987 a special meeting of IALA held at Trinity House in London expressed a common purpose to enhance and expand existing Loran-C coverage in North-West Europe and the North Atlantic. After two years of negotiation, agreement was finally reached in January of this year to proceed with the project. The countries involved are Canada, France, Germany, Iceland, Ireland, Netherlands, Norway and the United Kingdom, with cooperation from the United States and Denmark. They will re-equip six existing United States Coast Guard stations and use two French stations together with four new transmitters to provide four chains, covering the whole of NW Europe and most of the North Atlantic.
Safe Vertical Separation of Aircraft
Authors: Ratcliffe Stanley
Published: October 2009

A recent paper by Cox, ten Have and Forrester is planned to be the first of a series describing the work of the European Vertical Studies Sub Group (VSSG) set up under the ICAO panel for review of the general concept of separation. The present paper has no connection with the VSSG work.
Spectrum Management and the Impact of the GLONASS and GPS Satellite Systems on Radioastronomy
Authors: Ponsonby J. E. B.
Published: October 2009

This paper was presented at the West German-Soviet Workshop on Scientific and Industrial Cooperation in the use of GLONASS, held in Leningrad, USSR, September 1990. At this meeting, the author represented the Inter-Union Commission on the Allocation of Frequencies for radioastronomy and space research (IUCAF).
In the Wake of Columbus
Authors: Knox-Johnston Robin
Published: October 2009

This paper is based on the Eva G. R. Taylor lecture given by the author at the Royal Geographical Society on 28 November 1990. The precise landfall of Columbus in the New World has been the subject of discussion for many years owing to various interpretations of the information given by copies of his log and his own statement that his San Salvador lay about 28° north. The twofold aims of the author's 1989 voyage were: first, to experiment with fifteenth-century methods and instruments to find out by practical experimentation how accurate the navigation at the time might have been and so cast light on this 4° error in latitude; and secondly, to follow the navigation information given by Columbus as closely as possible to assess the effect of the currents on his dead reckoning as clues as to his landfall.
Collision and Grounding Risk Analysis for Ships Navigating in Confined Waters
Authors: Wennink Cornells J.
Published: October 2009

The present-day emphasis on the need to analyse and identify risk situations in ports is hardly a new phenomenon. In fact, port managements have, as a matter of course, been very conscious of this need but over the years, with the ever-increasing transport by sea of hazardous hydrocarbon, chemical as well as nuclear-related products, this need has simply become much more pronounced. Moreover, present-day public awareness and concern about the possible incident impact on the environment in the form of pollution or personal injury has even further increased the awareness of the corporate responsibility and the need to assess the operational risk levels of ports. Of equal importance, of course, is the need and the capability to predict operational risk levels for new port developments or modification projects or of the possible risks associated with the introduction of hazardous cargo-handling facilities at existing or new port terminals.
European Studies to Investigate the Feasibility of using 1000 ft Vertical Separation Minima above FL 290. Part II. Precision Radar Data Analysis and Collision Risk Assessment
Authors: Harrison D. , Moek G.
Published: October 2009

This paper is the second of a series of three papers, documenting the European studies into the feasibility of 1000 ft vertical separation minima above FL290. The paper discusses the vertical collision risk estimation methodology and an assessment of the collision risk against a target level of safety.

The analysis indicates the technical feasibility of a reduced vertical separation minima in the North Atlantic Region. However, for current operations and technical performance within European continental airspace, the risk estimation indicates that a 1000 ft minima is not technically feasible.

The contents of this paper reflect the views of the authors concerned; they do not necessarily reflect the official views or policy of the CAA or NLR.
Optimal Position Estimate from a Stars Fix with Correlated Errors
Authors: de Wit C.
Published: October 2009

This paper concerns the estimate of a ship's position from a sequence of measurements of 3, 4 or 5 altitudes of stars or planets. The measurement errors are assumed to be mutually correlated. This correlation is mainly caused by the appearance of so-called systematic errors. It is the main intention of this paper to dispense with the policy of pre-separation of these systematic errors. Instead, the equal contribution of some partial errors to the total measuring errors is fully accounted for by the formation of the covariance matrix, which corresponds with the vector of measurement errors. The algorithm produces a position estimate with a bias-free estimation error, meaning that the estimate and the error are stochastically independent. The resulting covariance matrix of the position error has a minimal trace.
Recent Progress in Weather Routeing for Merchant Vessels
Authors: Hopkins J. S.
Published: October 2009

The weather is rarely out of the news. Weather can be hazardous at times almost anywhere on Earth, and the media are always keen to report dramatic events. On the global scene, weather, climate and the environment are issues of great international public concern at present because of the likely implications of increases of greenhouse gases in the atmosphere. The contributions of the meteorologist to the understanding of this global problem are increasingly recognized, as is the progress which has been made in the accuracy of day-to-day forecasts. This paper provides a brief résumé of our present ability to model and forecast the behaviour of the global atmosphere and the ocean surface, and also demonstrates how these models are applied to the practical problems of operational ship-routeing by the UK Meteorological Office. It is worth remembering that it was the very high incidence of losses at sea in the 1850s which brought about the establishment of the UK's first meteorological service.
Quantitative Determination of Port VTMS Levels
Authors: Zhixiong Qiu
Published: October 2009

In this paper, a quantitative study is made of the determination of the level of a vessel traffic management system (VTMS) in a port. Also established is a mathematical model, which conforms to the actual situation in Chinese ports and which takes account of the ideas contributed by experts in relevant fields. With the help of the model, the port needs for VTMS are evaluated in a comprehensive and objective way, the overall levels of VTMS are determined and their corresponding standards set. A computer simulation verification has proven the effectiveness of the model.
Safer Navigation in the '90s — Integrated Bridge Systems
Authors: Hederström Hans , Gyldén Sven
Published: October 2009

This paper was presented at the SASMEX 92 Conference in London, April 7–9 1992. Permission to reproduce it is gratefully acknowledged.
The Eva G. R. Taylor Lecture: Navigators and Mathematical Practitioners in Samuel Pepys's Day
Authors: Wallis Helen
Published: October 2009

I am honoured that the Royal Institute of Navigation has invited me to give the E. G. R. Taylor lecture for 1992. These lectures, held annually, were funded by well-wishes in various societies to celebrate Professor Eva Taylor's 80th birthday. As a scholar, Professor Taylor moved in many spheres. I have chosen a subject which seems appropriate to her pioneering work in the history of navigation and the marine sciences.
The Air Traffic Capacity of Two-Dimensional Airspace
Authors: Ratcliffe S.
Published: October 2009

At the present day European ATC is exercised by a multiplicity of more-or-less autonomous control centres. ‘Flow Regulation’ is used roughly to match traffic demand to the capacity of the en-route ATC and of the destination airport. The ATC authority at the point of departure for a remote destination cannot however give any guarantee that the pilot will be able to follow his chosen trajectory. The filed flight plan and the departure clearance have been described as a ‘licence to get into the sky and see what happens’.
Navigation and Survey Techniques for the Development of North Sea Satellite Hydrocarbon Fields
Authors: Green Robert
Published: October 2009

The North Sea is at the leading edge of offshore hydrocarbon technology due to its hostile environment and deep water. This paper gives an overview of the role of the offshore surveyor in the North Sea by discussing the survey aspects, tools and techniques used in the development of a contemporary oil/gas field. Particular attention is paid to some of the more unusual techniques being developed today.
The Coast Guard's Differential GPS Programme
Authors: Alsip D. H. , Butler J. M. , Radice J. T.
Published: October 2009

The US Coast Guard has a project to provide a differential global positioning system service for harbour and harbour approach (HHA) areas of the coastal United States. The Great Lakes, Puerto Rico and most of Alaska and Hawaii will also be covered by the service. The Coast Guard's DGPS system will fulfil the 8–20 metre navigation accuracy requirement for HHA with an availability of up to 999 percent. The Coast Guard intends to provide this service to the general public and other government agencies, as well as use the system for its own missions. This capability is expected to enhance maritime safety in keeping with the National Transportation Policy by providing an all-weather radionavigation service to supplement existing radar and visual techniques, as well as a highly accurate position sensor for future electronic chart displays. This paper describes the Coast Guard's programme. Background and historical information on the development of pseudorange differential GPS is presented first, followed by a description of currently available technology. Various aspects of the Coast Guard's plan for implementing DGPS are then described, concluding with a rough project time line and a statement concerning Federal DGPS policy.
Navigation in Birds and Other Animals
Authors: Wiltschko Wolfgang , Wiltschko Roswitha
Published: October 2009

Many animals have some kind of ‘home’ –a nest, a burrow, etc. This applies to insects that build nests and provide their larvae with food just as much as to numerous species of vertebrates. Rodents and moles are known to dig burrows; most other mammals, reptiles, amphibians and even many fresh-water fish do not roam around randomly either, but have well-defined home ranges with favourite resting places in particular cavities, under rocks or in dense thickets. Birds build nests for their young and fly out searching for food. All these animals permanently face orientation problems: they have to move swiftly and efficiently within their home range, and they must be capable of returning home when they have left their familiar area while exploring, fleeing, etc.
The Use of Digital Map Data to Provide Enhanced Navigation and Displays for Poor Weather Penetration and Recovery
Authors: Bennett Peter J.
Published: October 2009

A GEC Marconi Avionics/MoD joint–funded integrated, digital terrain system called ' PENETRATE ' (passive enhanced navigation with terrain referenced avionics) is in its fourth year of flight trials on a Hunter fast–jet aircraft at the Defence Research Agency, Farnborough. Although originally designed to enable military aircraft to penetrate enemy defences at low level in poor weather conditions and at night, the system also has a direct read across to civil air transport operations. The heart of the PENETRATE system is a digital data–store housing a three–dimensional model of the terrain including cultural details, obstructions and tactical intelligence information.

PENETRATE incorporates terrain-referenced navigation to provide accurate position information relative to the ground contours. A sophisticated digital map displays navigation information and includes intelligence and intervisibility overlays. Head-up visual enhancement options are provided which can be tailored to the outside visibility. These comprise monochrome skeletal perspective displays which are superimposed on the outside world view and also on the forward-looking infra-red (FUR) scene. The display enhancements range from obstruction cues through ridge line overlays to skeletal perspective terrain presentations.

This paper covers the philosophy and architecture of PENETRATE together with details of the demonstration system. It also discusses the capability of this digital terrain system to enhance the safety of civil aircraft approaches into difficult airports such as Kathmandu and Hong Kong.
European Studies to Investigate the Feasibility of using 1000 ft Vertical Separation Minima above FL290 Part III Further Results and Overall Conclusions
Authors: Moek G. , Have J. M. Ten , Harrison D. , Cox M. E.
Published: October 2009

This is the concluding part of a series of three papers for this Journal, documenting the European studies into the feasibility of 1000 ft vertical separation minima above FL290. This paper outlines the results from European data collections other than the main precision radar data collection and expands upon the factors affecting height-keeping performance. The development of a Minimum Altimetry System Performance Specification (MASPS), necessary for a reduced vertical separation minimum above FL29O, is presented. A number of implementation issues, in particular monitoring, are also discussed.

The contents of this paper reflect the views of the authors; they do not necessarily reflect the official views or policy of the NLR, CAA or EUROCONTROL.
A Model Avian Compass Based upon a Magnetite Null Detector
Authors: Edmonds D. T.
Published: October 2009

A model avian compass is formed if magnetite crystals are included among the statoconia loading some of the hair cells in the vestibular system. The magnetite is used as a null detector to detect the direction in which the magnetic couple acting on the magnetic crystal is zero. The location of the north/south plane and the angle between the directions of the gravitational and the magnetic fields are detected at a single site.
Marine Navigation in the 21st Century: A Shift to Precision Navigation
Authors: Nijjer R. I. S.
Published: October 2009

This paper is based on one presented by the author at the Maritime Technology 21st Century Conference held at the University of Melbourne in November 1992.