bluuebunny/crossref_metadata_2025 huggingface dataset:
Which Emerges First: Bone Marrow Edema or Nidus in Osteoid Osteoma?
Authors: Uygur Esat , Poyanlı Oguz , Kılıçoğlu Onder
Published: February 2019

This case report describes a well-documented birth and evolution of an osteoid osteoma at the talus. Although initial radiologic images indicate mild bone marrow edema at first (without nidus), subsequent magnetic resonance imaging and computed tomographic images reveal pathognomonic nidus at the talus. During the evolution of the lesion, typical night pain was coincident with the occurrence of the nidus, as seen on magnetic resonance imaging. This may be interpreted that nidus formation may be related to the night pain. In this report, the first finding was bone marrow edema. Although our classic knowledge was that the edema follows the lesion, this report makes a difference. The relationship between bone marrow edema and osteoid osteoma has not been questioned in the literature before. We speculate that this report brings to mind, the question of which comes first? A bone marrow edema or nidus? Another question is: Does osteoid osteoma always start with such a dust cloud in the bone as we presented herein?
Methicillin-Resistant Staphylococcus aureus Endocarditis from a Diabetic Foot Ulcer
Authors: Hale Andrew J. , Vicks Emily , LaSalvia Mary T. , Giurini John M. , Karchmer Adolf W.
Published: February 2019

Diabetic foot infections are a common cause of morbidity and mortality in the United States, and successful treatment often requires an aggressive and prolonged approach. Recent work has elucidated the importance of appropriate therapy for a given severity of diabetic foot infection, and highlighted the ongoing risk such patients have for subsequent invasive life-threatening infection should diabetic foot ulcers fail to heal. The authors describe the case of a man with diabetes who had prolonged, delayed healing of a diabetic foot ulcer. The ulcer subsequently became infected by methicillin-resistant Staphylococcus aureus (MRSA). The infection was treated conservatively with oral therapy and minimal debridement. Several months later, he experienced MRSA bloodstream infection and complicating endocarditis. The case highlights the ongoing risk faced by patients when diabetic foot ulcers do not heal promptly, and emphasizes the need for aggressive therapy to promote rapid healing and eradication of MRSA.
Interprofessionalism
Authors: Joseph Robert , Robinson Richmond , Fleischer Adam , Jaffe Leland , Joseph Alison , Baker Isabel , Truong Jacqueline , Nouvong Aksone , Parsley Nancy L. , Becker John H.
Published: February 2019

In 1912, the Illinois College of Chiropody and Orthopedics was founded, and is today known as the Dr. William M. Scholl College of Podiatric Medicine. It has been an integral part of Rosalind Franklin University of Medicine and Science in North Chicago, Illinois since 2001. Through the ensuing decades, Scholl College alumni have been instrumental in moving the profession forward.
Humans strategically shift decision bias by flexibly adjusting sensory evidence accumulation
Authors: Kloosterman Niels A , de Gee Jan Willem , Werkle-Bergner Markus , Lindenberger Ulman , Garrett Douglas D , Fahrenfort Johannes Jacobus
Published: February 2019

Decision bias is traditionally conceptualized as an internal reference against which sensory evidence is compared. Instead, we show that individuals implement decision bias by shifting the rate of sensory evidence accumulation toward a decision bound. Participants performed a target detection task while we recorded EEG. We experimentally manipulated participants’ decision criterion for reporting targets using different stimulus-response reward contingencies, inducing either a liberal or a conservative bias. Drift diffusion modeling revealed that a liberal strategy biased sensory evidence accumulation toward target-present choices. Moreover, a liberal bias resulted in stronger midfrontal pre-stimulus 2—6 Hz (theta) power and suppression of pre-stimulus 8—12 Hz (alpha) power in posterior cortex. Alpha suppression in turn was linked to the output activity in visual cortex, as expressed through 59—100 Hz (gamma) power. These findings show that observers can intentionally control cortical excitability to strategically bias evidence accumulation toward the decision bound that maximizes reward.
Structure of a bacterial ATP synthase
Authors: Guo Hui , Suzuki Toshiharu , Rubinstein John L
Published: February 2019

ATP synthases produce ATP from ADP and inorganic phosphate with energy from a transmembrane proton motive force. Bacterial ATP synthases have been studied extensively because they are the simplest form of the enzyme and because of the relative ease of genetic manipulation of these complexes. We expressed the Bacillus PS3 ATP synthase in Eschericia coli, purified it, and imaged it by cryo-EM, allowing us to build atomic models of the complex in three rotational states. The position of subunit ε shows how it is able to inhibit ATP hydrolysis while allowing ATP synthesis. The architecture of the membrane region shows how the simple bacterial ATP synthase is able to perform the same core functions as the equivalent, but more complicated, mitochondrial complex. The structures reveal the path of transmembrane proton translocation and provide a model for understanding decades of biochemical analysis interrogating the roles of specific residues in the enzyme.
Rapid task-dependent tuning of the mouse olfactory bulb
Authors: Koldaeva Anzhelika , Schaefer Andreas T , Fukunaga Izumi
Published: February 2019

Adapting neural representation to rapidly changing behavioural demands is a key challenge for the nervous system. Here, we demonstrate that the output of the primary olfactory area of the mouse, the olfactory bulb, is already a target of dynamic and reproducible modulation. The modulation depends on the stimulus tuning of a given neuron, making olfactory responses more discriminable through selective amplification in a demand-specific way.
Integrating gross morphology and bone histology to assess skeletal maturity in early dinosauromorphs: new insights fromDromomeron(Archosauria: Dinosauromorpha)
Authors: Griffin Christopher T. , Bano Lauren S. , Turner Alan H. , Smith Nathan D. , Irmis Randall B. , Nesbitt Sterling J.
Published: February 2019

Understanding growth patterns is central to properly interpreting paleobiological signals in tetrapods, but assessing skeletal maturity in some extinct clades may be difficult when growth patterns are poorly constrained by a lack of ontogenetic series. To overcome this difficulty in assessing the maturity of extinct archosaurian reptiles—crocodylians, birds and their extinct relatives—many studies employ bone histology to observe indicators of the developmental stage reached by a given individual. However, the relationship between gross morphological and histological indicators of maturity has not been examined in most archosaurian groups. In this study, we examined the gross morphology of a hypothesized growth series ofDromomeron romerifemora (96.6–144.4 mm long), the first series of a non-dinosauriform dinosauromorph available for such a study. We also histologically sampled several individuals in this growth series. Previous studies reported thatD. romerilacks well-developed rugose muscle scars that appear during ontogeny in closely related dinosauromorph taxa, so integrating gross morphology and histological signal is needed to determine reliable maturity indicators for early bird-line archosaurs. We found that, although there are small, linear scars indicating muscle attachment sites across the femur, the only rugose muscle scar that appears during ontogeny is the attachment of theM. caudofemoralis longus, and only in the largest-sampled individual. This individual is also the only femur with histological indicators that asymptotic size had been reached, although smaller individuals possess some signal of decreasing growth rates (e.g., decreasing vascular density). The overall femoral bone histology ofD. romeriis similar to that of other early bird-line archosaurs (e.g., woven-bone tissue, moderately to well-vascularized, longitudinal vascular canals). All these data indicate that the lack of well-developed femoral scars is autapomorphic for this species, not simply an indication of skeletal immaturity. We found no evidence of the high intraspecific variation present in early dinosaurs and other dinosauriforms, but a limited sample size of other early bird-line archosaur growth series make this tentative. The evolutionary history and phylogenetic signal of gross morphological features must be considered when assessing maturity in extinct archosaurs and their close relatives, and in some groups corroboration with bone histology or with better-known morphological characters is necessary.
The blood parameters and liver function changed inconsistently among children between burns and traumatic injuries
Authors: Nie Chan , Wang Tao , Yu Huiting , Wang Xue , Zeng Xueqin , Wei Zairong , Shi Xiuquan
Published: February 2019

Objective

Burn and traumatic injury are two kinds of injury by modality. They cause acute phase response and lead to a series of pathological and physiological changes. In this study, we explored whether there are differences in routine blood parameters and liver enzyme levels between burned and traumatically injured children.

Methods

Patients under 18 years old with injuries were recruited. Their demographic and clinical data were recorded. Collected clinical data included routine blood parameters (white blood cell count (WBC), red blood cell count (RBC), platelets (PLT), hemoglobin (HB)), serological enzyme levels (alanine aminotransferase (ALT), aspartate transaminase (AST), glutamyltransferase (GGT), alkaline phosphatase (ALP), cholinesterase (CHE)), and total protein (TP) levels (albumin (ALB), globulin (GLB)). A generalized linear model and multivariate analysis of variance were used to conduct comparisons.

Results

A total of 162 children (109 with burns and 53 with traumatic injuries) with a mean age of 4.36 ± 4.29 years were enrolled in the study. Burned children had higher levels of RBC, HB, WBC, AST and lower levels of TP, CHE, ALB than traumatically injured children (P < 0.05). Moreover, the concentration of WBC and HB was higher in males compared to females (P < 0.001). Conversely, the level of AST and TP in males was lower, AST levels were significantly lower in males (P = 0.005). Age positively correlated with the levels of HB, AST and TP (P < 0.001), and negatively correlated with WBC (P < 0.001). With decreasing body mass index (BMI), the levels of WBC, HB, AST and TP significantly increased in both groups of injured children (P < 0.001). In addition, ISS was positively correlated with WBC and HB levels (P < 0.001), but negatively correlated with AST and TP levels (P < 0.001).

Conclusions

Children with burn injuries suffered a greater acute response and liver damage than traumatically injured children. This may in part underlie clinical observations of differences in children morbidity and mortality in response to different injury types.
THE EFFECT OF ROUGHNESS ON THE MASS-TRANSPORT OF PROGRESSIVE GRAVITY WAVES
Authors: Brebner Arthur , Askew J.A. , Law S.W.
Published: February 2019

On the basis of non-viscous small amplitude firstorder theory the maximum value of the horizontal orbital motion at the bed in water of constant depth his given by /U/n yy* »* " r -»** */i where k = /L, H is the wave height crest to trough, T is the period, and L the wave length (L = Sry2jr Arf 2*%/L ). On the basis of finite amplitude wave theory where the particle orbits are not closed ana by the insertion of the viscous laminar boundary layer (the conducti6n solution) the mean drift velocity or mass transport velocity on a perfectly smooth bed is given by Longuet- Higgins (1952) as 7, K H* kcr where
A POSSIBILITY OF GENERATION OF SURF BEATS
Authors: Unoki Sanae , Isozaki Ichiro
Published: February 2019

Indentations of a shoreline or ups and downs of sea bottom form a small oscillating system of water. When the period of natural oscillation in it is near that of advancing sea waves a forced standing oscillation develops there, accompanied by an uneven mean surface level of second order. If the height of the sea waves varies slowly with time, the mean surface fluctuates with the period same as that of the envelope of the sea waves, and such fluctuation will be sent back offshore as a surf beat when it is released by breaking of the original sea waves. The generated long wave seems to be correlated positively or negatively with the envelope of the sea waves, depending on the topography of the basin and the period of the incident sea waves. A possibility of generation of similar long wave in front of a breakwater or a steep beach is also suggested.
THE ECONOMIC VALUE OP A NEW BREAKWATER ARMOUR UNIT 'DOLOS'
Authors: Merrifield E.M. , Zwamborn J.A.
Published: February 2019

The Dolos, a new type of armour unit which closely resembles a normal ship's anchor, was developed and tried out under field conditions on the main breakwater of East London harbour. Since these full-scale Dolosse proved very successful, tests were made in a wave channel to compare the stability of Dolosse with other known types of armour blocks. The test results showed that the Dolos is outstandingly stable, and since manufacture and random placing of Dolosse offers no particular difficulties it is concluded that in many cases the use of Dolosse in armour layers may lead to more economical solutions for rubble mound breakwater and shore protection works.
ROCK MOVEMENT IN LARGE-SCALE TESTS OF RIPRAP STABILITY UNDER WAVE ACTION
Authors: Saville Thorndike
Published: February 2019

There have been several instances in the past four or five years of damage to the riprap protection of some earth dams and embankments in major reservoirs in the middle western portion of the United States. In particular, in small sections of the embankment of the Snake Creek sub-impoundment in the Garrison Reservoir in North Dakota, some riprap was removed by a severe storm in 1964. It was recognized at the time of construction that the riprap protection to be placed on this embankment was considerably lighter than desirable, and was knowingly placed as an experiment to see if lighter graded material might still provide sufficient protection in a reservoir where the water surface elevation changed periodically. High waves can develop over the 32-mile fetch in this area of frequent high wind velocity. Loss of some riprap in this area has led to an investigation of various schemes of upgrading the riprap. As a part of this investigation, tests have been made at the Coastal Engineering Research Center in Washington, D.C. of various types of riprap exposed to wave action. Tests have been made at both small and large scale. As with most wave tank tests of breakwater or embankment structures, the tests must be run as a short series of bursts of waves, followed by periods of calm. This is necessary because when the wave approaches the structure and breaks upon it, a small portion of the wave energy is not absorbed in the breaking process, but is reflected back along the wave tank. This reflected wave, upon reaching the wave generator, is re-reflected and travels again down the tank toward the structure. If mechanical generation of waves continues after the wave is re-reflected from the generator, this re-reflected wave adds to the mechanically generated wave, and gives a higher wave at the structure than is desired for tests. Accordingly, the wave generator must be stopped at the time the wave reflected from the structure has travelled to and reaches the generator. Thus the tests are run in a short burst of perhaps 10 or 1$ waves, followed by a period of time sufficient to allow the tank water level to calm, and then again a burst of 10 or 1'j waves.
THE EFFECT OF TWIT WEIGHTS OF ROCK AND FLUID ON THE STABILITY OF RUBBLE MOUND BREAKWATERS
Authors: Brandtzaeg Anton
Published: February 2019

To study the effect of the specific weights of armour block material and fluid on the stability of rubble mound breakwaters a total of 110 model tests were made, with varying specific weights of armour and fluid, sizes of blocks and slopes of the breakwater face. The tests indicate that in cases where the specific weights deviate much from usual values, the current design formula (Eq. (1)) should be modified by entering a variable quantity,
FULL-SCALE INVESTIGATION OF BERTHING IMPACTS AND EVALUATION OF A HYDRAULIC-PNEUMATIC FLOATING FENDER
Authors: Lee Theodore T.
Published: February 2019

Two experimental hydraulic-pneumatic floating fenders (camels) were in-service tested in protected and exposed harbors. Due to their high energy-absorption characteristics, the fenders were effective in reducing damage to piers, pier-fender systems, and berthing or moored ships. Their performance relative to a number of individual ship-impacts is discussed, conclusion^drawn, and recommendations made. Measurements as a function of time of ship velocity, berthing force, position of point of impact, and energy absorption by fenders are presented and discussed for 35 berthings involving 14 ships of from 1,400 to 17,600 tons displacement. Load-deflection and energy-absorption curves of the hydraulic and pneumatic fender bags are presented and discussed, and results compared with those predicted by theory. Berthing forces and energy-absorption characteristics are analyzed statistically; their relationships with point of impact are compared with those established with a model of a tanker by the Hydraulic Research Station, Wallingford, England. The resistance to ship motion including hydrodynamic effect is analyzed. It is concluded that hydrodynamic effect is an important parameter which requires further investigation. It is recommended that full-scale tests of berthing impact at exposed harbors be continued and that model tests of berthing impact be initiated, particularly tests of the resistance to ship motion, so that hydrodynamic mass can be properly evaluated.
RESISTING TORQUES OR FORCES ACTING OX THE SPUDS OF THE PUMP DREDGER ON THE SURFACE WAVES
Authors: Iwasaki Toshio
Published: February 2019

This paper presents the analysis on the resisting torques and forces acting on the spuds mooring the pump dredger for the surface waves. Torque or force was expressed by the product of the system factor, the statical wave factor and the magnification factor.
Complete Proceedings - Single PDF Download
Authors: O'Brien Morrough P.
Published: February 2019

Coastal engineering is one of the many inter-disciplinary fields of professional study and practice which has appeared in recent years on the periphery of the traditional fields; civil engineers, oceanographers, mathematicians, physicists, statisticians, petroleum production engineers and many others participate to some degree in this field which has as its common denominator the phenomena and the physical design problems of the zone where land and ocean meet. The Coastal Engineering Council, formerly the Council on Wave Research of the Engineering Foundation, was organized to promote research and to provide a medium of communication among workers in the field. It became evident after the first conference at Long Beach in 1950 that research in progress was extensive and reasonably well-supported and that the most effective function of the Council would be to sponsor occasional conferences in countries active in coastal studies. The proceedings of these conferences, ably edited by our Secretary, Professor J. W. Johnson, form an encyclopedia of theory, laboratory studies, field observations, design methods, case histories in coastal morphology, and in the lore and knowledge characteristic of an active phase of engineering practice, in which judgment based upon experience plays as large a role in design as theory. All of us who practice in this area owe Professor Johnson much gratitude for his incisive editorial work and his skillful financial management which has made these proceedings so readily available.
APPLICATION OF FLUORESCENT COATED SAND IN LITTORAL DRIFT AND INLET STUDIES
Authors: Stuiver Minze , Purpura J.A.
Published: February 2019

The use of fluorescent coated sand In tracing the sand movement along beaches and around Inlets is an important tool in the field of Coastal Engineering. As a part of an extensive beach erosion study along the shore of West Palm Beach, Florida, four areas were subjected to such a "tracer study." Each area represented a particular beach configuration either with or without erosion protective structures. In this paper the procedure and results for one area is described. As a second application of sand tracers, the results of a study concerned with the sand migration in and around South Lake Worth Inlet is discussed.
QUANTITATIVE TRACING OF LITTORAL DRIFT
Authors: Bruun Per
Published: February 2019

Tests were run at Fernandina Beach, Florida, using fluorescent tracers and bed load traps with automatic doors and hydraulic lift to determine the thickness of the bed load transport layer on the bottom ("bottom creep") (ref.l). Four special bed load traps with hydraulic remote controlled doors were installed on an ab. 800 ft. long pier. Fig. 1. Tracers of various colours were dumped at various distances from the pier. Two types of bottom profiles, Fig. 2, "berm profile" and Fig. 3, "bar-profile" were tested. As an example Fig. 4 shows test arrangement and wave action for test No. 17 (berm profile). Longshore wave power for this particular test was 1,5 Watts per ft of wave (one Watt is ab. 0,1 kg m/sec or ab. 0,0014- Horse Power), H, ,, was o,45 m, T, ,,, was 4-5 sec.
LITTORAL DRIFT AS FUNCTION OF WAVES AND CURRENT
Authors: Bijker E.W.
Published: February 2019

For the computation of littoral drift due to waves hitting a coast obliquely, most formulae are based upon the assumption that this longshore transport is some function of the energy flux of the waves towards the coast. For the actual computation the component of this flux parallel to the coast is introduced. Most of the available prototype data are incorporated m the formula of the U.S. Army Coastal Engineering Research Center (ref. 4 and 1). In this formula no reference is made to the gram size and the slopes of beach and foreshore. The explanation for the fact that nevertheless reasonable results are obtained is probably owing to the fact that variation of gram size and beach slope for sandy beaches is not so very great. A more serious disadvantage is, however, that it is not possible to take into account the influence of a possible longshore current which is not generated by the wave motion, such as for instance tidal currents. In this paper an attempt is made to compute the littoral drift, starting from the longshore current velocity as it is generated by the waves or as it may originate from other causes (ref. 4). For the actual computation of the bed load transport a normal bed load transport formula is used, in which, however, according to the method developed by the author in earlier studies, the bed shear is increased as a result of the wave motion (ref. 2). From the tests briefly described in the present paper it becomes clear that the transport may be treated indeed as a function of the longshore current, even when this current has a direction opposite to that of the component of the wave propagation parallel to the coast.
THE TERMINAL PROBLEM IN COAST PROTECTION
Authors: Pallett N.
Published: February 2019

This paper introduces the terminal erosion problem which usually occurs down drift of coast protection works, an important aspect of coast protection which is often overlooked. To provide the background to this problem, the formation, replenishment and function of a natural shingle beach is discussed m relation to coast protection. The value of groynes in stabilising the foreshore, the use of artificial beach replenishment, and the effect on the long shore regime following the introduction of a sea wall, are discussed m outline with typical examples. Terminal erosion is described in more detail, with reference to its cause, and illustrated by examples taken around the coast of the British Isles. Suggestions are made for the investigation of the terminal problem, design considerations are discussed, and terminal groynes and various types of terminal works described. Particular reference is made to the permeable type of terminal section. Finally the paper is illustrated by examples of terminal works which have been constructed at two sites m this country. The foreshore conditions and exposure are described, together with the details of the sea wall and groynes, and the details of the terminal works at each site.
RECESSION OF MARINE TERRACES - WITH SPECIAL REFERENCE TO THE COASTAL AREA NORTH OF SANTA CRUZ, CALIFORNIA
Authors: Sorenson Robert M.
Published: February 2019

The concept "wave base" (or "surf base"), i.e. the maximum depth below mean sea level at which shoaling waves will effectively erode the ocean bottom leading to the recession of a shoreline, is discussed. Also, past and present opinions as to the magnitude of wave base in general and specifically in the area near Santa Cruz, California, and the variables controlling this phenomenon are presented. Then, an account of the author's successful and unsuccessful attempts to determine average rates of cliff retreat in the study area is presented along with the specific cliff recession rates obtained. These compare favorably with the recession rates measured by the U. S. Army Corps of Engineers for nearby areas of similar geology and topography and with rates determined for similar coastal areas in various parts of the world. A brief discussion of the spectrum of cliff recession rates found m areas of varying geology and wave climate is also presented. The accepted history of sea level since the last glacial maximum, particularly during the last 7,000 years, is reviewed as well as pertinent information on the geology, topography and wave climate of the study area. It is then shown that average recession rates estimated by relating extrapolated bedrock profiles of the lowest marine terraces with the accepted history of the latest sea level rise compare favorably with the recently measured recession rates. However, a conflict exists between the present wave-cut terrace profiles, the accepted history of sea level and the accepted value of wave base.
STABILITY OF QUADRIPOD COVER LAYERS
Authors: Weymouth Olin F. , Magoon Orville T.
Published: February 2019

The purpose of this paper is to present the results of a four-year study of the stability of a prototype breakwater armor layer composed of 28-ton concrete quadripods The study was conducted by measuring the incident wave height and the quadripod movements during this period. The ultimate goal of this study is the verification of empirical breakwater design equations.
EXPERIMENTAL INVESTIGATION OP SHOCK PRESSURES AGAINST BREAKWATERS
Authors: Richert Gustaf
Published: February 2019

This paper describes an experimental investigation of shock pressures against breakwaters caused by "breaking waves. The study only considers shocks of a compressive type, which occur if the wave front is formed in such a way that an air cushion is entrapped between the wave and the wall. In this case the compression and expansion of the air cushion plays an important role m the pressure variation. Only waves preceded by non-breaking waves were used. For different combinations of bottom geometry and water depth the occurrence of shock pressures of different magnitudes was studied varying the wave height and the wave period. For some interesting combinations of bottom geometry and wave dimensions a series of tests were made to investigate the distribution over the wall of shock pressure and of shock impulse. The results, presented m diagrams and tables, have been commented on and analysed with special respect to the chosen test procedure.
FLEXIBLE POROUS FLOATING BREAKWATERS
Authors: Kennedy R.J. , Marsalek J.
Published: February 2019

Observation of the effect of towed rafts of pulpwood on lake and ocean waves led to a systematic investigation at model scale. An empirical equation compatible with wave theory was devised and lines representing this equation together with points representing experimental results are shown for different conditions. An example of the application of the equation to prototype wave action is given. Four box booms with porous fronts, arranged m series, were substituted for the model pulpwood gam and proved to be effective m damping waves.
DESIGN OF A SMALL TIDAL INLET
Authors: O'Brien Morrough P. , Zeevaert Leonardo
Published: February 2019

Estero Punta Banda on the Pacific Coast of Baja California was to be improved and stabilized as a small boat harbor by the construction of twin jetties. The throat area-tidal prism relationship at this entrance agreed with that of other inlets on sandy coasts in equilibrium. This throat area was retained in the jetty spacing. The major question to be resolved was whether to retain the entrance in its present position at the north end of the lagoon or to cut a new entrance at the south end. The former position was chosen.
RIVER MOUTH TRAINING IN NEW SOUTH WALES, AUST.
Authors: Floyd C.D.
Published: February 2019

A summary is given of the results of training sixteen rivers in an endeavour to increase bar depths for navigation. The bars are of simple crescent formation fed by littoral drift. Whilst the training works have improved conditions for navigation they have not resulted in any appreciable increase in bar depths. Despite the complex mechanisms involved in bar formation a consistent simple correlation is found to exist between channel and bar depths. This correlation seems to apply to all rivers and inlets with simple bar systems and extends over a range from a bar depth of two feet to 60 feet. The correlation holds for rivers elsewhere and-- with varying climates of exposure.
EXPERIENCE WITH SELF-DREDGING HARBOUR ENTRANCES
Authors: Donnelly P. , MacInnis I.
Published: February 2019

About 7 years ago, the Department of Public Works of Canada requested the assistance of the National Research Council to devise a means of reducing sediment deposition in the entrance to a small harbour at Dmgwall, Nova Scotia. Siltation of this harbour entrance, which opens to the Atlantic, was so severe that on occasions it was completely blocked by sand at low tides. The desired objective was to devise a layout of structures which would maintain an entrance depth of 12 feet at low tide. Model studies were carried out and a breakwater configuration was evolved which appeared to have some "selfdredging" characteristics. The recommended structures were built in 1962 and to date have been successful in maintaining minimum depths of 5 feet at low tide which is adequate for the fishing fleet using the harbour. While falling somewhat short of the original objective this performance has been very satisfactory when compared with the conditions which existed before construction. Similar installations have since been built at two other locations in Nova Scotia Which are on the Gulf of St. Lawrence. Indications so far are that similarly satisfactory results have been obtained. This paper describes the installations, makes some tentative suggestions concerning the mechanisms involved m their operation and provides data on their performance.
A SYSTEMS APPROACH TO PETROLEUM PORT SITE SELECTION
Authors: Gaither William S. , Sides J. Patrick
Published: February 2019

Petroleum port site selection is examined in the broad context of the total transportation system from production to consumption area. Basic systems engineering approaches are applied to the problem to formulate a mathematical model which permits all transportation system variables, including capital and operating costs, to be put in quantitative form. An example of the computer solution is given, along with a discussion of the principal calculations involved. Unit transportation cost is selected as the measure of effectiveness of candidate systems. The port site associated with the system yielding the lowest unit transportation cost for the entire range of throughputs is selected.
STUDIES OP PREDICTION OF RECIRCULATION OP COOLING WATER IN A BAI
Authors: Wada Akira
Published: February 2019

In the present report, a few factors of great importance in the determination of the degree of recirculation of cooling water for power station are chosen for theoreti cal analysis First, the problem of flow and thermal diffusion in the &ea caused by outfall of warmed cooling water is considered. Numerical solution of the equation of thermal diffusion with a complete set of Eulerian equations in which the value? of the eddy coefficient of diffusion and viscosity depend upon the relation to the velocity shear and vertical density gradient is presented The Boussinesq approximation LS used throughout The mechanism of development of upwellmg phenomenon is discussed from the numberical experiment taking into account of the interaction between the flow and the thermal distribution. From the result of field survey, the occurrence of the return flow m the bottom layer oi the coastal region is confirmed The numerical solutions give a good representation of all features of flow and thermal profiles. Next, study on cold water intake from bottom layer is presented The numerical experiment of the stratified fluid with a continuous density gradient flowing into the submerged intake is conducted to gain additional insight into the mechanism of density flow in the field of the continuously stratified fluid. The results lead to the conclusion that the flow in the field of the continuous distribution of density differs from that for a two-layer system.
RECTANGULAR RESONATORS FOR HARBOUR ENTRANCES
Authors: James William
Published: February 2019

A complete theoretical analysis of the behaviour of resonators built into the breakwaters of a harbour entrance would be extremely difficult. This paper describes an approximate development for extreme values of resonator geometry and shows how a combination of these cases explains certain observed phenomena for intermediate shapes. The paper also describes comprehensive laboratory tests on resonators and draws attention to certain significant discrepancies from present design practice. In particular, the paper indicates the extent to which optimum resonator geometry depends upon the harbour entrance width and demonstrates that such resonators can be designed to prevent any penetration of waves into harbours, without restricting shipping.
THE MOTIONS OF SMALL BOATS IN STANDING WAVES
Authors: Raichlen Fredric
Published: February 2019

Some dynamical aspects of the surge motions of small boats moored asymmetrically with elastic non-linear restraints are discussed herein. In connection with the theoretical analysis of mooring dynamics, experiments were conducted to determine the periods of the free oscillations of a 26-ft boat moored in various ways in a floating slip. These results are in reasonable agreement with those predicted theoretically. An analytical study of the mooring dynamics of seven small boats indicated that the periods of free oscillation were less than about 10 sec. , hence, for these boats the important wave periods for forced oscillations would be in the range of those of storm waves.
THE CANADIAN WAVE CLIMATE STUDY - THE FORMATIVE YEAR
Authors: Draper Laurence
Published: February 2019

This paper describes the need for, and the factors involved in, the establishment of a Wave Climate Study, illustrated with particular reference to the Canadian Wave Climate Study.
ON THE HYDRODYNAMIC FORCES OF TWIN-HULL VESSELS
Authors: Wang Shen
Published: February 2019

The added mass and damping coefficients for semi- and fully submerged twin cylinders in vertical motion are determined as functions of the oscillation frequency, the cylinder spacing ratio, and the cylinder submergence ratio It has been found that resonance may occur in particular combinations of cylinder spacing and oscillation frequency at which the hydrodynamic mertial and damping characteristics deviate from the trend curves for the case of a single cylinder Justification of using the two-dimensional results to calculate motions of three dimensional twin-hull vessels is discussed It is suggested that, by means of strip theory approach, these results can be used to estimate the hydrodynamic forces for catamaran type vessels in pitch and heave motions.
ENVIRONMENTAL PLANNING OF A BAY AND COASTAL LAGOON SYSTEM
Authors: Gilroy Norman T.
Published: February 2019

The 1970s are, it seems, the beginning of an "age of environmental awareness " Never before has our nation been so conscious of the necessity for protection of the quality of its waters, its air, its aesthetic environment, and the productivity of its earth, and never has it been so aware of the potential, within man's actions for progress for the pollution of his environment or the creation of imbalance within the natural dynamic system The realization is growing that the system of natural dynamics, the ecosystem and the natural aesthetic environment in which we live are, in fact, part of a complete interrelated, interdependent and synergistic "Environmental System " Man made modification of any part of the System carries with it the potential of effects extending throughout the rest of the system, often resulting in major, and at times catastrophic, modification of the natural balance of the physical environment as we know it today Though the principles of environmental sensitivity are only newly being adopted by our media, our community leaders and our elected officials, there are some who have been advocating and practicing the principles of environmental planning for some time It has long seemed logical that major engineering or planning programs, capable of generating extensive modifications to the environment into which they are interposed, should be considered, throughout all their phases in terms of the entire spectrum of environmental factors which make up the site and its surroundings-yet rarely is this the case An area of particular environmental sensitivity lies in our ocean and along our coastline Here nature's forces are at their most dynamic, while her ecological delicacy is often at its most vulnerable The ocean's waters frequently act as a transfer medium, permitting the impact of man's modification at a specific location to be felt over great distances We need only to remember any of numerous examples of the loss of beaches, radical modification of coastline characteristics, extensive changes or virtual annihilation of segments of our coastal ecosystem, and the effects of heated waste water emitted from power plant cooling systems upon adjacent ecosystems, to be aware of the potential effects of man's change upon downcoast areas within the ocean system.
SEDIMENT POLLUTION IN COASTAL WATERS
Authors: Van de Kreeke J.
Published: February 2019

Sediment pollution can be defined as the increase in sediment concentration, due to artificial infusion of sediment, to a level harmful to fish and plant life The coastal engineer may be called upon to evaluate the result of an artificial sediment influx in terms of characteristic parameters like concentration and turbidity and to determine eventual deposition areas of the sediment This paper describes the field investigations carried out to evaluate a case of sediment infusion in one of the estuaries on the U S east coast The sediment was discharged via a pipeline at a rate of approximately 10 lbs/sec Nearly all the released sediment was in the silt range In addition to the results of the field measurements a simple mathematical model is presented, describing the temporal and spatial distribution of the sediment in the resulting sediment plume.
EXPERIMENTAL STUDIES ON THE GENERATION OF WAVES IN SHALLOW WATER
Authors: Kuo C.T. , Tang Frederick L.W.
Published: February 2019

The seas in front of China coast such as Yellow Sea, East China Sea and Taiwan Straits are all located on continental shelf. In consequence, waves approaching these coasts are generated in shallow water area in comparsion with wave length. The authors has developed tangible calculation procedures for evaluating the wave features in such areas in stationary or moving fetches (l). However, the basical formulas of calculation are derived from experimental data of Bretschneider and Thijsse. In order to investigate the generating process of shallow water wind waves and obtain more detailed informations for correcting calculation criteria, a series of experiments have been performed at a wind tunnel of 75 meters in length. Various investigations on the relationships between waves and wind as well as water depth ar4 to be submitted in this paper. In addition, the situation of wind wave coexistance with regular wave is studied from experiments, because it resembles the superposition of refracted and local wind waves on the western coast of Taiwan.
THE MEASUREMENT OF TIDAL WATER TRANSPORT IN CHANNELS
Authors: Klein R.E.
Published: February 2019

For the electromagnetic flow measurement in straits, channels etc use is made of the electric potential difference between two points m the bottom, near the moving water. The potential difference can be put down to natural causes the water is an electric conductor and moves m the magnetic field of the earth There are a number of quantities and variables that are of importance for the measured signal Beside this, the measurement is above all a matter of eliminating some disturbances Information about the two measuring systems as applied m The Netherlands is given m this article.
WAVE FORECASTING FOR THE WEST COAST OF IHDIA
Authors: Dattatri J. , Renukaradhya P.S.
Published: February 2019

The applicability of the general Wave Forecasting procedures like the SMB and the PNJ methods, to the Indian coasts is studied. The study consisted in analysing the bynoptic charts to obtain the necessary wind characteristics. The computed wind characteristics were used in the above Forecasting methods to yield significant wave heights These were compared with the wave characteristics as recorded by a sub-surface pressure type recorder after suitable modifications to account for the attenuation of wave pressure with depth. The predicted wave heights compare well with the recorded wave heights and the SMB method predicts wave heights better for the case studied.
BOTTOM BOUNDARY SHEAR STRESSES ON A MODEL BEACH
Authors: Teleki P.G. , Anderson M.W.
Published: February 2019

The maximum amplitude of shear stress in the bottom boundary layer of water waves was evaluated with a Preston probe inclined on a 1 12 5 slope beach Near bottom velocity profiles were obtained in laminar and developing turbulent flow conditions from which the experimental boundary layer thicknesses were evaluated Agreement between experimental bottom velocities and those calculated from Airy theory deteriorate with decreasing depth on the beach resulting m lower shear stress values than predicted by linear theory The measured boundary layer thickness on the slope exceeds the predicted for horizontal bottom, increasing shoreward to some critical depth outside the breaker zone from where it decreases shoreward The influence of roughness on the shear stress distribution is considerable m the "offshore" region, but becomes negligible near the breaker zone On a smooth bottom the coefficient of friction agrees with Kajiura's expression.
A SYSTEM FOR MEASURING ORBITAL VELOCITIES IN WAVES
Authors: Kolpak M.M. , Eagleson P.S.
Published: February 2019

A single-ended, cylindrical hot-film sensor and a directionvane transducer are studied as instruments for measuring flow fields in laboratory waves Errors in the hot-film measurements are discussed in terms of sensor voltage and water temperature drifts, and directional sensitivity The response of the direction-vane transducer is discussed in terms of the parameter b/r, which is the ratio of the vane chord length to the radius of curvature of the measured orbital flow The instruments are tested in a laboratory wave system, using stationary and traversing measuring techniques The velocity measurements so obtained are compared to those obtained by a photographic technique, to determine instrument error The flow speed comparisons indicate that the maximum hot-film error in flow speed measurements is between + 5 and ±1 0 inches/sec for the range 1 to 11 inches/sec tested The flow direction comparisons indicate that the direction vane response is subject to errors larger than 5° for fo/r>0 1 The study was carried out under the sponsorship of the Coastal Engineering Research Center at the Massachusetts Institute of Technology and is reported in full detail in the M.I T. Hydrodynamics Laboratory Report No 118.
SHOALING OF FINITE-AMPLITUDE WAVES ON PLANE BEACHES
Authors: Chan Robert K-C , Street Robert L.
Published: February 2019

This work focuses on the shoaling of large water waves with particular application to storm-generated waves and tsunamis The specific objective is the exact simulation on a digital computer of finite-amplitude waves advancing on a beach of constant slope The study is based on the simulation technique called SUMMAC (the Stanford-University-Modified Marker-And-Cell Method) The flow field is represented by a rectangular mesh of cells and by a line of hypothetical particles which defines the free surface Based on the Navier-Stokes equations, finite-difference equations were derived so that the entire flow configuration could be advanced through a finite increment of time The pressure and velocity components are used directly as the dependent variables Through extensive analyses and numerical experiments, this scheme was found to be computationally stable if the cell size and the time increment are properly selected As a specific example, the dynamics of a solitary wave passing from a zone of constant depth onto a sloping beach were simulated Primary attention was focused on the details of the water particle motions and the changes in the amplitude and shape of the wave as it climbed the slope The computed results are compared with the experiments with good agreement.
PERIODIC WAVES SHOALING IN WATERS OViR STEEPLY SLOPING BOTTOMS
Authors: Ayyar Harihara Rama
Published: February 2019

The bottom bed slope plays a vital role m the shoaling and breaking of periodic waves. This study aims at the understanding of the effect of steep slopes (range steeper than 1 10) on the breaking point and the breaker trajectory and the point of impact. This range of slope is often met with in. the near-shore structures. Analytical investigations and model studies are outlined. The influence of slope on each of the significant breaker parameters is discussed.
PROBABILITIES OF BREAKING WAVE CHARACTERISTICS
Authors: Collins J. Ian
Published: February 2019

Utilizing the hydrodynamic relationships for shoaling and refraction of waves approaching a shoreline over parallel bottom contours a procedure is developed to transform an arbitrary probability density of wave characteristics in deep water into the corresponding breaking characteristics in shallow Water A number of probability distributions for breaking wave characteristics are derived m terms of assumed deep water probability densities of wave heights wave lengths and angles of approach Some probability densities for wave heights at specific locations in the surf zone are computed for a Rayleigh distribution in deep water The probability computations are used to derive the expectation of energy flux and its distribution.