bluuebunny/crossref_metadata_2025 huggingface dataset:
American Orthopaedic Association’s (AOA) Council of Orthopaedic Residency Directors (CORD) Summer 2017 Conference: Top Abstracts
Authors: Harrington Melvyn ,   on behalf of the CORD/Academics Committee
Published: May 2018

This article is the first in a collaboration between the American Orthopaedic Association’s (AOA) Council of Orthopaedic Residency Directors (CORD) and JBJS to highlight selected abstracts presented at the Summer CORD Conference. These abstracts all serve to support the purpose and mission of CORD:

“The American Orthopaedic Association’s Council of Orthopaedic Residency Directors (CORD) program strives to recognize best practices in orthopaedic residency education and fellowship education based on ACGME [Accreditation Council for Graduate Medical Education]-defined essential knowledge and skills in each of the residency education competency areas. CORD provides a forum for academic orthopaedic leaders to exchange ideas, discuss solutions to challenges, and find ways to effectively teach residents in orthopaedic programs.”

The following abstracts were presented at the Summer 2017 CORD Conference in Charlotte, North Carolina. They are excellent examples of education-related research and will hopefully inspire more investigation into this much-needed area.
Student’s Descriptive Text Writing In SFL Perspectives
Authors: Noprianto Eko
Published: May 2018

Descriptive text is one of genres which is demanded be mastered by high school students in Indonesia. This requires teachers to be able to deliver it well in the classroom. However, research discovered that many teachers still have limited knowledge of how to effectively teach genres in the classroom. This qualitative case study was intended to diagnose a student’s descriptive text writing through SFL perspectives to find out what problems encountered in her text writing. It is expected that after finding the problems, the teacher could design a pedagogical plan to deal with them. The results showed that the student’s major problems in writing descriptive text lied on three aspects: the inability in adjusting the social function of the text, difficulty in writing the descriptive text with a chronological schematic structures, and the difficulty in filling the text with appropriate language features such as the use of unspecific participant. Therefore, taking everything into consideration, the researcher proposed Discovery Learning model to be used in teaching descriptive text in the classroom due to its strengths.
La compensación en los procesos concursales. Su regulación en el derecho argentino.
Authors: Gerbaudo Germán E.
Published: May 2018

La compensación es un modo extintivo de las obligaciones que presenta especiales controversias en los procesos concursales. Así sucede también en el derecho argerntino.
Serum concentrations of some acute phase proteins in cats with anaemia
Authors: TUNA GÜLTEN EMEK , DINLER CEREN , AŞICI GAMZE SEVRI EKREN , ULUTAŞ BÜLENT
Published: May 2018

Serum concentrations of acute phase proteins can provide valuable diagnostic information in the detection and monitoring of disease. The available information on the acute phase response in cats with anaemia is limited. The aim of this study was to retrospectively evaluate serum concentrations of haptoglobin, serum amyloid A, α1 acid glycoprotein and their clinical importance in cats with anaemia. Thirty-four anaemic cats and ten healthy cats were enrolled this study. After individual diagnoses had been established, the cats were divided into three groups (healthy group, haemolytic group and non-haemolytic group). Serum acute phase protein concentrations were analysed using specific commercially available test kits in an ELISA reader device. Serum amyloid A and serum α1 acid glycoprotein concentrations were significantly higher in the anaemic groups compared with the healthy group. Haptoglobin concentrations were significantly higher in cats from the non-haemolytic anaemia group than they were in healthy animals and those from the haemolytic anaemia group. Although serum haptoglobin concentrations were lower than in the healthy group, there was no significant difference between the haemolytic anaemia group and the healthy group. The results of this study suggest that serum amyloid A and α1 acid glycoprotein could be useful in the diagnosis and determination of inflammation in cats with anaemia. Serum haptoglobin depletion may be used for diagnosis of haemolysis in cats with haemolytic anaemia. In addition, this study has contributed to the limited data available on acute phase protein concentrations in cats with anaemia..
Coagulation system in horses in the aspect of comparative pathology
Authors: ABRAMOWICZ BEATA , MILCZAK ANDRZEJ , KACZMAREK BEATA , KUREK ŁUKASZ , RIHA TOMASZ , LUTNICKI KRZYSZTOF
Published: May 2018

The coagulation system, which is responsible for maintaining an organism’s hemostasis, is present in all mammals; nevertheless, there are differences in the dynamics of processes of coagulation activation and fibrinolysis in individual species. In horses, the development of hemostasis processes is different at all stages in comparison to humans. Primary hemostasis is maintained at a relatively low number of thrombocytes with coexisting differences in the structure and morphology of blood platelets. For many years, primary hemostasis has been determined solely on the basis of coagulation time; currently, lumiagregometry or impedance aggregation is used. New techniques and technologies allow an ever broader view of the pathogenesis of many diseases in terms of the coagulation system’s abnormalities, which either stand for an etiologic factor or only accompany the disease (they are its result). In the course of horse colic, especially in acute and recurrent forms, there are several changes in the parameters of the hemostatic system. It is believed that DIC is the most common coagulopathy. However, there is are no definite life-extending criteria as well as postmortem diagnosis of this syndrome. Changes in blood rheology after exercise are primarily due to an increase in hematocrit. The impact of exercise on the coagulation system in horses was analyzed, and showed a tendency in EPIH horses for the occurrence of hypercoagulability with the prolongation of blood coagulation parameters. The role and the contribution of the coagulation system in the etiopathogenesis of equine laminitis is not clear; in the case of carbohydrate overdosage microtrombosis, reduced platelet survival and their over-aggregation have been reported. Clinical studies in sick animals show that coagulopathy such as DIC and antithrombin deficiency are not primary factors in the etiopathogenesis of laminitis..
Role of C-reactive protein determination to assay the inflammatory process in the course of ovarian cysts in female dogs
Authors: WDOWIAK ANNA , DUDZIAK ADRIANNA , SZCZUBIAŁ MAREK , KUSY ROLAND , BOCHNIARZ MARIOLA , ŚMIECH ANNA , TVARIJONAVICIUTE ASTA , DĄBROWSKI ROMAN
Published: May 2018

Searching for new more accurate biomarkers in order to evaluate the health of bitches with reproductive disorders and disturbances has been a subject of inquiry for many researchers. Biomarkers are measurable indicators, the concentrations of which are dependent on the degree and type of stimulus. Serum C-reactive protein (CRP) has been proven to be a valuable biomarker for health status evaluation of bitches suffering from reproductive disorders, such as pyometra, as well as for treatment monitoring. However, no data are available related to the CRP profile in bitches with ovarian cysts for a better evaluation of their condition and prognosis. Thus, the aim of this study was to determine the possible usefulnessof CRP determination in the serum of bitches with ovarian cysts. Our results suggest that CRP concentrations could be useful indicators of the presence of ovarian cysts, although studies with more animals are needed..
Brucellosis in Mirpur, Azad Kashmir Pakistan: a livestock threat for neighboring zones
Authors: MUBEEN HADIA , KHAN* IAHTASHAM , SALEEM MUHAMMAD HASSAN , AKHTAR RAHEELA , ALI SHAHZAD , SAQIB MUHAMMAD , KHAN AMAN ULLAH , UMAR SAJID
Published: May 2018

The objective of the present study was to determine the prevalence of brucellosis in household animals of Mirpur, Azad Kashmir due to its geographic importance. A total of 360 blood samples of cattle, buffaloes, sheep and goats were initially screened through Rose Bengal Plate test (RBPT) and then positive samples were subjected to Enzyme Linked Immunosorbent Assay (ELISA) for confirmation and quantification of antibody titers. Molecular confirmation of serologically positive samples was performed by real time polymerase chain reaction (PCR). RBPT and ELISA showed a total of 8.6% and 6.87% positive samples respectively. The species wise seropositivity by RBPT was greater in cattle followed by buffaloes, goats and sheep. Similarly ELISA showed more seropositivity in cattle than buffaloes, while sheep and goats were negative for brucellosis by ELISA. RT-PCR revealed 100% samples positive for Brucella abortus by species specific PCR. This study revealed the presence of Brucella abortus in Mirpur for the first time. Since brucellosis is listed in transboundary diseases, its presence in this geographically important region could be a potential threat for neighboring countries..
First evaluation of new design concepts for self-cleaning distribution networks
Authors: van den Boomen M. , van Mazijk A. , Beuken R. H. S.
Published: May 2018

Ten years of joint research on the nature and causes of discoloured water has resulted in guidelines for the implementation of self-cleaning distribution networks. These were first introduced in the Netherlands in 1999. The self-cleaning concept has been monitored right from its beginnings. Based on this evaluation, significant observations were found on the contribution of changes in flow velocity to the self-cleaning characteristics of pipes. These observations will be further investigated and will form the basis for the concept of dynamic sediment transportation modelling.
Hydroinformatics and its applications at Delft Hydraulics
Authors: Mynett Arthur E.
Published: May 2018

Hydroinformatics concerns applications of advanced information technologies in the fields indeed the very success of hydroinformatics is directly associated with these applications. The aim of this paper is to provide an overview of some recent advances and to illustrate the practical implications of hydroinformatics technologies. A selection of characteristic examples on various topics is presented here, demonstrating the practical use at Delft Hydraulics. Most surely they will be elaborated upon in a more detailed way in forthcoming issues of this Journal. First, a very brief historical background is outlined to characterise the emergence and evolution of hydroinformatics in hydraulic and environmental engineering practice. Recent advances in computational hydraulics are discussed next. Numerical methods are outlined whose main advantages lie in their efficiency and applicability to a very wide range of practical problems. The numerical scheme has to adhere only to the velocity Courant number and is based upon a staggered grid arrangement. Therefore the method is efficient for most free surface flows, including complex networks of rivers and canals, as well as overland flows. Examples are presented for dam break problems and inundation of polders. The latter results are presented within the setting of a Geographical Information System. In general, computational modelling can be viewed as a class of techniques very much based on, and indeed quite well described by, mathematical equations. These equations often symbolically represent underlying physical phenomena, like conservation of mass, momentum and energy. Diversification to application areas where no clear mathematical formulation may (yet) be present but where adequate data sets are available is illustrated by several practical examples. Again, using computer based technologies, various applications of so-called sub-symbolic techniques like Artificial Neural Networks (ANNs) are discussed and presented. Finally, some reflections on forthcoming developments and likely implications for engineering practice as well as education are outlined.
Fides et Ratio: a critical appraisal
Authors: Abbot Michael B.
Published: May 2018

Book review: Faith and Reason: Evangelical letter Fides et Ratio of the supreme pontiff John Paul II to the bishops of the Catholic Church on the relation between faith and reason, 1998, Libreria Editrice Vaticana/Veritas, Dublin.
Rainfall and runoff forecasting with SSA–SVM approach
Authors: Sivapragasam C. , Liong Shie-Yui , Pasha M. F. K.
Published: May 2018

Real time operation studies such as reservoir operation, flood forecasting, etc., necessitates good forecasts of the associated hydrologic variable(s). A significant improvement in such forecasting can be obtained by suitable pre-processing. In this study, a simple and efficient prediction technique based on Singular Spectrum Analysis (SSA) coupled with Support Vector Machine (SVM) is proposed. While SSA decomposes original time series into a set of high and low frequency components, SVM helps in efficiently dealing with the computational and generalization performance in a high-dimensional input space. The proposed technique is applied to predict the Tryggevælde catchment runoff data (Denmark) and the Singapore rainfall data as case studies. The results are compared with that of the non-linear prediction (NLP) method. The comparisons show that the proposed technique yields a significantly higher accuracy in the prediction than that of NLP.
Water-quality modelling of the Upper Mersey river system using an object-oriented framework
Authors: Spanou Maria , Chen Daoyi
Published: May 2018

The aim of this paper is to present the recent advances in the development of an object-oriented software system for water-quality management, and discuss the results from its application to the study of the Upper Mersey river system in the United Kingdom. The software has been extended and includes tools for the construction of flow duration and low-flow frequency curves using different methods, the sensitivity analysis and parameter estimation of the water-quality model, and the stochastic simulation of the mass balance at the discharge points of point-source effluents. The application of object-orientation has facilitated the extension of the software, and supported the integration of different models in it. The results of the case study are in general agreement with published values. They also include low flow estimates at the ungauged river sites based on actual data for the artificial sources, and water-quality simulation results, which have not been presented earlier in the literature for the Upper Mersey system.
HydroWeb: ‘WWW based collaborative engineering in hydroscience’—a European education experiment in the Internet
Authors: Molkenthin Frank , Belleudy Phillippe , Holz K.-Peter , Jozsa Janos , Price Roland , van der Veer Peter
Published: May 2018

Modern information and communication technology enables new technical solutions to support collaboration in engineering over distance. The application of Web based project platforms and collaboration methods requires new kinds of soft skills, knowledge and experience—a task for education and training in hydroinformatics. This technical note describes a pan-European education experiment, where students from five European universities have solved a given engineering task in distributed teams in the Internet. The collaboration was based on the principle of ‘information sharing’ using a Web based project platform. In this course the students acquired experience in interdisciplinary teamwork, net based project co-ordination and Web based reporting. They strengthened their social competence to collaborate in heterogeneous teams with different habits, nationalities, ages and educational backgrounds. The described experiment might be the basis for introducing Web based collaborative engineering in the regular course programme of water related curricula.
Verification and application of a mathematical model for the assessment of the effect of guiding walls on the hydraulic efficiency of chlorination tanks
Authors: Stamou Anastasios I.
Published: May 2018

A mathematical model is applied to the tank of Kipseli in Athens, Greece, which is used for storage, balancing and emergency chlorination. A Flow-Through Curve (FTC) experiment is performed for the initial geometry of the tank. The shape and the characteristics of the FTC show a very poor hydraulic efficiency, with extensive short-circuiting, intense mixing and low detention times. To improve the hydraulic efficiency of the tank the use of four alternative arrangements of guiding walls is examined by the model. Prior to its application, the model is verified by comparing the predicted FTC with the experimental. A satisfactory agreement is observed between the calculated and the experimental curves. Then the model is applied to calculate the flow field and the FTC for the four arrangements. Calculations are compared and the arrangement which shows the highest hydraulic efficiency is proposed for construction.
Generalized Boltzmann equation for shallow water flows
Authors: Ghidaoui Mohamed S. , Li Nanzhou
Published: May 2018

This invited review paper introduces the Boltzmann-based approach for the numerical modelling of surface water flows to hydroinformaticians. The paper draws upon earlier work by our group as well as others. This review formulates the generalized Boltzmann equation for 1D and 2D shallow water flows and shows that the statistical moments of these generalized equations provide the classical continuity and momentum equations in shallow waters. The connection between the generalized Boltzmann equation and classical shallow water equations provides a framework for formulating new computational approaches to surface water flows. To illustrate, a first-order explicit scheme based on the generalized Boltzmann equation for 1D shallow waters in frictionless and horizontal channels is formulated. The resulting scheme is applied to the classical dam break problem. Comparison with the analytical solution shows that the Boltzmann-based scheme is highly accurate and free of spurious oscillations, illustrating the potential of the method for surface water problems and other applications.
Uncertainty and risk in water quality modelling and management
Authors: McIntyre Neil R. , Wagener Thorsten , Wheater Howard S. , Yu Zeng Si
Published: May 2018

The case is presented for increasing attention to the evaluation of uncertainty in water quality modelling practice, and for this evaluation to be extended to risk management applications. A framework for risk-based modelling of water quality is outlined and presented as a potentially valuable component of a broader risk assessment methodology. Technical considerations for the successful implementation of the modelling framework are discussed. The primary arguments presented are as follows. (1) For a large number of practical applications, deterministic use of complex water quality models is not supported by the available data and/or human resources, and is not warranted by the limited information contained in the results. Modelling tools should be flexible enough to be employed at levels of complexities which suit the modelling task, data and available resources. (2) Monte Carlo simulation has largely untapped potential for the evaluation of model performance, estimation of model uncertainty and identification of factors (including pollution sources, environmental influences and ill-defined objectives) contributing to the risk of failing water quality objectives. (3) For practical application of Monte Carlo methods, attention needs to be given to numerical efficiency, and for successful communication of results, effective interfaces are required. A risk-based modelling tool developed by the authors is introduced.
Reliability analysis of water distribution systems
Authors: Ostfeld Avi
Published: May 2018

Reliability is an integral part of all decisions regarding water distribution system layout, design, operation and maintenance. Providing reliability for water distribution systems is complicated due to the many factors that affect reliability, the inherent nonlinear behavior of the system and its consumers, and due to the different conflicting objectives facing a water distribution system utility. Although the reliability of water distribution systems has received considerable attention over the last two decades, there is still no common, acceptable, reliability measure or reliability assessment methodology. This paper describes the classification and reliability analysis methodologies of water distribution systems and compares two previously published algorithms for reliability evaluation of water distribution systems: a tailor-made ‘lumped supply–lumped demand’ approach used most commonly in regional water distribution systems and a general stochastic (Monte Carlo) framework suitable for any generic network.
NUMERICAL ANALYSIS OF FINITE DEPTH PROBLEMS IN SOIL-WATER HYDROLOGY
Authors: WATSON K. K.
Published: May 2018

The types of initial and boundary conditions which may be involved in the flow of water through an unsaturated profile to a water table are discussed. A numerical solution of the flow equation is then outlined and its use in the one-dimensional drainage of a homogeneous profile and in ponded infiltration into a draining profile detailed. Several characteristics of the drainage of deep profiles are discussed together with numerical solutions for the drainage of a stratified profile and infiltration into a draining profile.
COMPARISON OF DIMENSIONLESS UNIT HYDROGRAPHS IN THAILAND AND TAIWAN
Authors: SCHULZ EDMUND F. , PINKAYAN SUBIN , KOMSARTRA CHUMPORN
Published: May 2018

The characteristics of dimensionless unit hydrographs were derived from floods from watersheds smaller than 1000 square kilometers located in Thailand. The dimensionless unit hydrographs were expressed as ratios of q/qq as a function of t/tp. These dimensionless unit hydrographs were compared with similar unit hydrographs derived from floods on Taiwan and with the unit hydrographs derived from a mathematical model developed from the two parameter gamma function developed from the theory of the instantaneous unit hydrograph. It was found that the unit hydrographs derived from the Thai watersheds had much longer base length and much longer time to peak than similar unit hydrographs derived from floods on Taiwan. This increase in length of response time is attributed to a larger component of subsurface runoff believed to be present in the floods from tropical watersheds.
IN SITU DETERMINATIONS OF pH IN SOME LAKES
Authors: GRÖTERUD OLAV
Published: May 2018

pH has been determined in some lakes by using an in situ technique. pH has also been measured in the usual way in the field and in the laboratory. These measurements, together with the determinations in situ, made it possible to get information about changes of pH in the water samples during sampling, measuring, and storage. The microstratification of pH has also been investigated by means of in situ determinations.
DETERMINISTIC APPROACH TO WATERSHED MODELING
Authors: WOOLHISER DAVID A.
Published: May 2018

Physically-based, deterministic models, are considered in this paper. Physically-based, in that the models have a theoretical structure based primarily on the laws of conservation of mass, energy, or momentum; deterministic in the sense that when initial and boundary conditions and inputs are specified, the output is known with certainty. This type of model attempts to describe the structure of a particular hydrologic process and is therefore helpful in predicting what will happen when some change occurs in the system.
POLE-TO-POLE WATER BALANCE FOR THE IGY FROM AEROLOGICAL DATA
Authors: PEIXOTO JOSE P.
Published: May 2018

The present study gives a discussion of the water balance on a planetary scale during the IGY covering the mean and the seasonal conditions for the calendar year 1958. The study includes analyses of the amount of precipitable water, of the vertically integrated transport vector field and of the divergence of water vapor flux for all the globe. Some implications of the water vapor distribution in the atmosphere, its transport, and divergence fields are deduced which bear some importance for hydrology. The water balance based upon the various water vapor fields is examined and the inferred values obtained from the analysis of the water vapor divergence field are compared with estimates of evaporation and precipitation obtained from independent climatological sources.
GROUND WATER IN GRANITE ROCKS AND TECTONIC MODELS
Authors: LARSSON INGEMAR
Published: May 2018

A systematic study has been carried out concerning ground water in faults and fractures in a granite rock and the results are compared with those of uniaxial testing of granite specimens in rock mechanic laboratories. Dikes of diabase intersect the granite and indicate the plane of deformation syntectonic to the dikes. A collection of the tectonic data from the granite is statistically treated and the tectonic picture of the area fits very well into the deformation plane, indicated by the intrusion (Jotnian).

The faults and fractures of the granite are, according to their position in relation to the plane of deformation, hypothetically interpreted as tension and shear faults. The faults in shear position are supposed to be tight and have very little ground water. The tension faults, on the other hand, are supposed to be open and to be capable of a high yield of ground water. This hypothesis is tested by core-drillings, percussion drillings and test pumping.
SNOW-WATER EQUIVALENT MEASUREMENT USING NATURAL GAMMA EMISSION
Authors: GRASTY R. L.
Published: May 2018

The natural gamma radiation emitted by potassium, uranium and thorium is attenuated by snow. This attenuation depends on the water-equivalent of the snow layer. Air absorption coefficients were determined by flying at different altitudes over a uniform test strip and used to calculate the absorption coefficients for water. Results using the Geological Survey of Canada high sensitivity airborne gamma-ray spectrometer showed that snow water-equivalents up to 18 cm could be measured to an accuracy of 2 cm over suitable terrain. The importance of temperature and soil moisture corrections are discussed, together with statistical, instrumental and navigational errors.
EVAPOTRANSPIRATION AND PLANT PRODUCTION DIRECTLY RELATED TO GLOBAL RADIATION
Authors: ASLYNG H. C.
Published: May 2018

This article is based on the thesis, that when sun radiation is not in excess and advected energy supply can be neglected, then for periods of plant cover and growth, both evapotranspiration and plant production are linearly and strongly related to global radiation.

The regression coefficients will depend also on plant, soil and other climatic factors, but global radiation will be the dominating factor for potential evapotranspiration and potential plant production in given regions.
SEASONAL VARIATIONS AND STATIONARITY
Authors: GUDMUNDSSON G.
Published: May 2018

The paper presents a method for testing second order stationarity against the alternative that seasonal variations take place in the autocovariance function. This is a modification of a test suggested by Priestley & Rao (1969) based on the concept of “evolutionary spectra”. The method was applied to actual series of monthly data of discharge, temperature and precipitation. Seasonal variations in mean and variance were eliminated before the test was applied, but highly significant seasonal variation was still present in some series.
STOCHASTIC TIME DISTRIBUTION OF STORM RAINFALL
Authors: KNISEL W. G. , SNYDER W. M.
Published: May 2018

Increments of rainfall during a storm event were treated as stochastic variates. Statistical distributions of accumulated rain were developed at 2-hour intervals. Three-parameter lognormal distributions were then fitted simultaneously to the twelve 2-hour histograms by making two of the three parameters continuous functions of elapsed time from beginning of rainfall. After evaluation of the parametric functions by nonlinear least squares, stochastic patterns of storm rainfall can be simulated.
Seasonal Variability in the Pole-to-Pole Water Vapor Balance During the IGY
Authors: Peixoto Jose P. , Rosen Richard D. , Wu Mao-Fou
Published: May 2018

A study of the vertically integrated fields of water vapor and its transport on a planetary scale derived from aerological data taken during the IGY (International Geophysical Year) is presented. The focus is upon the seasonal variability in these fields, with maps of the total zonal and the total meridional flux of water vapor given for each of two semester seasons. The analyses are discussed in the light of various climatological and hydrological considerations. Results from the analysis of our aerological data are used to study the balance of water on zonal and planetary scales, and comparisons are made with evidence provided from climatological sources. The aerological approach to the study of the hydrological cycle is seen to be a valuable one.
A Sediment Transport Model for Straight Alluvial Channels
Authors: Engelund Frank , Fredsøe Jørgen
Published: May 2018

The paper presents a simple mathematical model for sediment transport in straight alluvial channels. The model, which is based on physical ideas related to those introduced by Bagnold (1954), was originally developed in two steps, the first describing the bed load transport (Engelund 1975) and the second accounting for the suspended load (Fredsøe and Engelund 1976). The model is assumed to have two advantages as compared with empirical models, first it is based on a description of physical processes, secondly it gives some information about the quantity and size of the sand particles in suspension and the bed particles.
Experiences with the Use of the Aerological Method in Evaporation Studies in Northwestern Europe
Authors: Alestalo Mikko , Savijärvi Hannu
Published: May 2018

Two different approaches of the aerological method were used for estimating evaporation in northwestern Europe in the period 1969-1970.

Daily operational aerological observations (»the synoptic approach«) gave better results for homogeneous areas (e.g. the Baltic Sea) than for a nonhomogeneous surface. One drawback in this approach was the non-uniform station network due to a lack of observations and resulting in scattered values even for monthly means.

Based on annual mean moisture fluxes at the aerological stations (»the statistical approach«) the evaporation from the Bothnian Sea was estimated to be about 300 mm/year. The main convergence of the water vapor flux occurred below the 900 mb level and was largely due to the mean part of the flux. The results appeared to be quite dependent on the homogeneity of the data sample.

In both approaches the main source of error is the lack and low quality of data, because divergence calculations are sensitive to errors in wind data. The linearity approximation used may also fail in low levels. Careful data checking and the use of complete data samples are needed when the aerological method is applied.
Measurement of Vertical Recharge to Groundwater in Haryana State (India) Using Tritium Tracer
Authors: Goel P.S. , Datta P.S. , Tanwar B.S.
Published: May 2018

Downward movement of soil moisture due to rainfall and supplemental irrigation in the unsaturated zone has been followed by tagging a layer of soil with tritiated water at a number of sites in the state of Haryana. The activity apparently moves by a piston type flow. The average recharge for 15 sites during the interval July - November, 1973 has been equivalent to 9 cm of water which is 14% of the irrigation plus rainfall. For 18 sites sampled after two monsoons (July 1973 to December 1974) the average recharge is 19 cm and the fractional recharge is 0.15. Wide variations in recharge values are noted. The most significant factor affecting the fractional recharge is the clay content of the soil.
Groundwater Recharge in Panjab State (India) Using Tritium Tracer
Authors: Datta P.S. , Goel P.S.
Published: May 2018

Vertical recharge to groundwater due to the 1972 monsoon plus supplemental irrigation has been measured at 21 sites in the state of Panjab (India) using tritium tracer. Average recharge is found to be equivalent to 8.5 cm of water. This is about 18% of the average rainfall and 12% of the total watering.
Crossings and Extremes in Dependent Annual Series
Authors: Rosbjerg Dan
Published: May 2018

Crossing characteristics of a discrete stationary process with Markov properties are re-examined. A new extreme value distribution is developed and compared with extreme values obtained from long-term annual streamflow records.
Longitudinal Grain Sorting by Current in Alluvial Streams
Authors: Deigaard Rolf , Fredsøe Jørgen
Published: May 2018

The longitudinal current sorting of graded sediment is analysed by use of a sediment transport formula developed recently by Engelund and Fredsøe (1976). The analysis yields that for a given longitudinal profile of a river, the longitudinal variation in mean grain diameter and the grain distribution curve is unique determined by the sediment input and water discharge. No requirement concerning an ultimate equilibrium state of the bed elevation is introduced. The analysis yields that the mean grain size will decrease as the slope of the river decreases and further, that originally logarithmic normally distributed sand will tend to be logarithmic hyperbolic distributed after sorting.
Analysis of Hydrologic Data Using Pearson Type III Distribution
Authors: Shaligram V. M. , Lele V. S.
Published: May 2018

Computation of reliable and precise long term estimates from the available short term hydrologic records is often a challenging task for the design engineers/hydrologists.

Peak flow magnitudes relating to ‘sixteen’ streams were utilised for deriving long term estimates using Maximum likelihood method (Gumbel 1941 and Panchang et al. 1962). The results revealed that most of peak flows were underestimated and their departures from the respective prototype magnitudes were of the order of 10 to 40 per cent.

These peak flow magnitudes were graduated by the Pearson type III distribution with the result that a perfect calibration (departure within 1 per cent only) was achieved for three streams. For remaining streams the departures were reduced and were within 20 per cent.

The precision of the estimates, deduced from the use of the Pearson type III distribution, was ascertained by evaluating the confidence intervals for these estimates. For three cases the confidence intervals (deduced from the latter distribution) were smaller than their counterparts deduced from the Gumbel's distribution. For the remaining streams' data, the confidence intervals were nearly double those obtained with the Gumbel's distribution. Thus to achieve conformity between prototype and model (using the Pearson type III distribution), one has to be content with even slightly less precise estimates, but which are, otherwise, realistic.
Modelling of Water Exchange in an Estuary
Authors: Sarkkula Juha , Virtanen Markku
Published: May 2018

A two-dimensional horizontal hydrodynamical model has been used to estimate the changes that a harbour road will cause in the water exchange of an estuary. The research area has been the Kokemäenjoki river estuary on the coast of the Gulf of Bothnia in western Finland.

The numerical model has been verified on the basis of a regression model describing the water exchange of the estuary at present with a multiple correlation squared of 0.9. The factors having an influence on the water exchange are the wind, the sea level fluctuation and the river discharge.

The changes in the water exchange have been considered during a dry spell, a flood period and an average year with three different cross-section areas of the road line. The accuracy and reliability of the estimation are found to be very satisfactory.
Wind Induced Circulation in Lakes
Authors: Bengtsson Lars
Published: May 2018

In most lakes the wind is the most important flow generating mechanism. In this paper the problem of wind generated circulation - directly wind induced currents and seiches - in small lakes is reviewed. Many field observations are presented and discussed. In the thermocline and the hypolimnion forced seiche currents are shown to dominate the directly induced wind currents. Different kind of non-convective mathematical lake models are discussed and applied to different small lakes. Comparisons of observed and calculated currents show that lake models can be used to reproduce the currents of the upper 3–4 metres in a lake. The interaction between large-scale flow and turbulent flow is yet unknown, and therefore it is not possible to explain the physical current pattern and density anomalies at greater depth. In respect to the limited knowledge on turbulent processes in lakes, it is acceptable to apply a quadric relationship between wind stress and wind speed with a drag coefficient of about 1.0.10−3..
Examination of the Summer Stratification
Authors: Svensson Urban
Published: May 2018

The seasonal stratification in lakes is examined by a qualitative evaluation of important physical processes and with the aid of a mathematical model. From the description of the physical processes it is realized that the observed vertical temperature distribution is the synthesis of a number of complicated and inter-dependent phenomena. The mathematical model is employed for a quantitative estimate of the importance of lake morphometry and transparency. It is found that the vertical variation of horizontal area and variations in transparency strongly influence the thermal structure of a lake. Measurements of the temperature distribution in Lake Velen are compared to predictions obtained by the mathematical model. The agreement is found to be satisfactory and it is concluded that the mathematical model provides a realistic way of studying and predicting the summer stratification.
An Approach to Calculating Evaporation Rates at Remote Sites
Authors: Ovadia D. , Pegg R. K.
Published: May 2018

This paper describes work which has been undertaken to assess the feasibility of calculating evaporation rates for remote sites in North Wales from the recordings taken at a central site. In the course of the work it was found that data derived from radiosonde ascents and published in the Daily Aerological Records proved to be beneficial in the analysis.
A Comparison of Some Methods for Estimation of Potential Evaporation
Authors: Kristensen K. J.
Published: May 2018

In most of the important agricultural regions of the world, evaporation in the growing season exceeds the precipitation, and also often the sum of precipitation and plant available water in the root zone. This causes a need of supplemental irrigation for effective agricultural use. Information about the greatest possible water consumption in given periods, therefore, is important for the water policy of a given region.

Several methods for estimation of the maximum (potential) evaporation have been suggested, and many methods have been compared earlier (W.M.O. 1966, Heldal 1969, Kristensen 1971, Iruthayaraj and Marachan 1978).

In Denmark a screened sunk iron pan has been used as a standard since 1956 (Aslyng and Hansen 1960). This standard pan and other methods for estimating potential evaporation have been compared during a 15-year period. The results are reported and discussed.
Critical Examination of the Muskingum Method
Authors: Gill Mohammad Akram
Published: May 2018

The Muskingum method of flood routing is critically reviewed. The kinematic wave approach is used to compare and contrast the conclusions deducible from the conventional hydrological approach. The importance of the time lag concept is emphasised.
Sediment Transport by Wind and Water
Authors: Bagnold R.A.
Published: May 2018

In connection with the 50th anniversary of Aarhus University, 11 September, 1978, brigadier R.A. Bagnold, F.R.S., was conferred the honorary degree of Doctor of Science. The present paper is the manuscript of the lecture R.A. Bagnold was giving at the faculty of science. In the lecture R.A. Bagnold expreses his views on several aspects of sediment transport in air and water. Among the most famous works by R.A Bagnold are the monograph The Physics of Blown Sands and Desert Dunes, 1941 (Chapman & Hall, London) and the paper Flow of Cohesionless Grains in Fluids, 1956 (Royal Soc.London, Phil.trans.A.249, 235–297). Many of the thoughts presented in the present paper have their roots in these two works.
Elemental Composition of Norwegian Rivers
Authors: Salbu B. , Pappas A. C. , Steinnes E.
Published: May 2018

Instrumental neutron activation analysis has been applied for the determination of up to 40 elements in waters from eleven Norwegian rivers. In order to represent the composition of an average river in the region of Norway and possibly the greater part of the Scandinavian peninsula, weighted mean values are calculated on the basis of geometric mean values and discharge of the individual rivers. Factor analysis shows that Cambro-Silurian sedimentary and vulcanic rocks influence the water composition considerably compared to Precambrian gneisses and granites. An influence of airborne supply is evident in coastal areas. In addition ore deposits are important for Zn and associated elements.

Comparison with literature data from Sweden shows good agreement for the elements concerned. The present values concerning alkalies, alkaline earths and halogens are, however, significantly lower than the estimated “world averages”. This is probably due to a low abundance of marine deposits and sedimentary rocks in Scandinavia. Low values are also found for elements which are often associated with particulate matter (Fe, Al, V, Mo, As, Sb, Th, U), while the values obtained for rare earths (La, Ce, Sm) and some additional elements (Sc, Mn, Au) are significantly higher than the estimated “world averages”.
Hydrochemistry in Geothermal Investigations in Iceland Techniques and Applications
Authors: Arnórsson Stefán
Published: May 2018

The role of hydrochemistry in geothermal exploration and development is described. During the surface exploration phase hydrochemistry is particularly useful in delineating regional ground-water movement, in estimating underground temperatures, and in mapping the areal extent of geothermal systems. From data obtained through exploratory and investigation, drilling hydrochemistry yields information on the direction of underground geothermal water flow, mixing processes, boiling in the aquifer, and distribution of underground temperatures. It also contributes significantly in defining and solving scaling and corrosion problems and is relevant for environmental aspects of fluid disposal and constructional design.
Penetration and Distribution of Tritiated Water in Soils of a Lysimeter
Authors: Fodor-Csányi Piroska , Takala Stina , Alhonen-Hongisto Leena , Miettinen Jorma K. , Horváth Gábor L. , Vakkilainen Pertti , Soveri Jouko
Published: May 2018

A lysimeter experiment was carried out to determine the penetration and distribution of a water pulse applied on the soil surface as a tritium labelled simulated precipitation (30-60 mm). Three plots of soil (each 10 m2, 1.5 m deep) were used, one filled with gravel, the others with fine sand. In gravel the pulse penetrated ca. 50 cm in the first week, in the fine sand plots less than 15 cm. In gravel the tritium maximum penetrated the lysimeter in 150 days, in fine sand much later. The results were compared with theoretically calculated values.
Relationships between Precipitation Chemistry, Hydrology, and Runoff Acidity.
Authors: Skartveit Arvid
Published: May 2018

High precipitation amounts of strongly varying ionic composition make the western parts of southern Norway well-suited for studies of certain relationships between precipitation chemistry, hydrology, and runoff acidity. Ions from sea-spray are the predominant ions in precipitation in these areas. The remaining ions are almost exclusively acidifying compounds (H+, NH4+, SO42−, NO3−), negatively correlated to the sea-spray ions.

Hydrochemical observations during 5 years confirm that Cl− and, to a considerable extent, also SO42− move rather easily through the catchments, while NO3− is strongly adsorbed. The acid top soil tends to lead to acid surface runoff, while water penetrating deeper mineral soils becomes enriched in Ca2+ and depleted in H+, resulting in a high correlation between runoff acidity and runoff rate. The short-term variations in runoff acidity are thus governed largely by runoff rate and by atmospheric deposits of Cl− and SO42−. In this particular precipitation climate this yields in fact a negative short-term correlation between precipitation acidity and runoff acidity.

A long-term acidification, indicated by declining fish populations, does probably arise from a SO42− -increase in runoff (caused by increased atmopheric deposition), and from a change in soil properties (caused by acid precipitation, and possibly also by changed vegetation).
Measurement and Mapping of Potential Evapotranspiration in a Small Mountainous Watershed
Authors: Najjar G. , Ambroise B. , Mercier J.L.
Published: May 2018

The potential evapotranspiration ETP can be estimated by using Brochet and Gerbier's formula (1972), which is derived from Penman's equation

ETP ≡ mRg + n Ep (mm/day),

where m and n are tabulated coefficients depending on season, latitude and shelter type, and where the variables are the global solar radiation Rg and the Piche evaporation under shelter Ep.

In the small Ringelbach watershed (36 ha), in the Vosges Mountains (France), maps of daily ETP have been calculated with this formula, by mapping these two variables

- maps of daily global radiation have been computed for sunny days from horizontally measured Rg, by taking into account slopes, aspects and orographic masks.

- small and cheap Piche shelters, specially designed and calibrated, have been implanted over the whole watershed with Ep measured twice a day.

The results obtained for Rg, Ep and thus ETP reveal important differences within the watershed. Their spatial patterns depend on weather type, topographic structure, and soil surface humidity.

This mapping procedure, which gives a good estimation of ETP, enables us to better understand the hydrologic behaviour of any mountainous watershed.
Measuring and Modelling Snowmelt in Dyrdalen, Western Norway, 1979 and 1980
Authors: Harstveit Knut
Published: May 2018

During spring snowmelt 1979 and 1980 the runoff from the snowpack was recorded by lysimetry from a 9 m2 area. Wind speed, air temperature, air humidity, radiation, and precipitation data were also recorded. When the melting rate (= snowpack runoff-rainfall) and the net radiation were measured, the turbulent heat exchange between the snowpack and the atmosphere was computed as a residual from the energy balance equation of the snowpack. These computed values were used to find “optimal” empirical constants in aerodynamical equations expressing the turbulent fluxes as functions of the wind speed and the temperature/vapour pressure differences between the measurements 2 m above the ground (0.6-1.5 m above the snow surface) and the values at the surface. These empirical constants agree reasonably well with constants found by other investigators.

Averaged over the two melting seasons, sensible heat flux represents 65%, and net radiation represents 35% of the energy consumed in melting, while 13% was gained from condensation, and 13% was lost by evaporation. When the weather conditions varied during the melting season, the energy balance model yields better results than does the degree-day-model. Residual errors were 7.3 mm (42%) and 13.2 mm (76%), respectively. The maximum melting observed in 24 hours was 110 mm, and the snowmelt rate in overcast days was about 3 times the rate when the cloudiness was light, provided the same wind and temperature conditions and albedo ~ 70%.