Kinds Of Pools Research Articles

An approach to optimised control of HVAC systems in indoor swimming pools

Indoor swimming pools are recognised as having a high level of energy consumption and present a great potential for energy saving. The energy is spent in several ways such as evaporation heat loss from the pool, high rates of ventilation required to guarantee the indoor air quality, and ambient temperatures with expressive values (typically 28−30°C) required to maintain conditions of comfort. This paper presents an approach to optimising control of heat ventilation and air conditioning systems that could be implemented in a building energy management system. It is easily adapted to any kind of pool and results in significant energy consumption reduction. The development and validation of the control model were carried out with a building thermal simulation software. The use of this control model in the case study building could reduce the energy efficiency index by 7.14 points (7.4% of total) which adds up to an energy cost saving of 15,609€ (7.5% of total).

Experimental Study on Hydraulic Characteristics of Pool-Type Fishway

Fishway is an effective engineering measure to keep the river longitudinal connectivity and maintain aquatic biodiversity. In this experiment, the pool-type fishway with asymmetric notches and orifices was studied, the ADV was employed to measure the velocity data in the pools, the flow velocity and flow regimes in the pools with the length of 0.5m, 0.6m and 0.7m at different measuring lines were analyzed. The results show that the maximum velocity is 0.35±0.025m/s in the three kinds of pools, and both the backflow region and the backflow velocities are correspondingly increased with the increasing length of the pool.

Development of Steel Folding Type Fishway and its Characteristics

Pool and weir type fishway is a kind of open channel with slope of constant gradient and connects a drop in a river. When this kind of fishway is built at high dam or debris barrier, it must inevitably be long and large, which induces high cost and long construction period. Recently, spiral fishway that is also a kind of pool and weir type but folded like a spiral has been developed to overcome the difficulties and installed to some high dams. It sometimes fail to dissipate energy and often slant its talwag outward, though it succeeds in cut-down of the cost and period according to some reports. Then, the spiral fishway is improved to be successive S shape channel with shallow pools and attached directly on the wall of barrier. At the same time the fishway that consists of several parts made of steel is built in a factory and the parts are assembled on the site, which cut the cost and period remarkably down. In the research its applicability are examined by hydraulic test and fish ascending test in a prototype experimental fishway. Results show that 1) flow is successfully decelerated throughout the fishway and approximately 28% of velocity is reduced at a folding pool, 2) flow at pools is slower than sustained speed of young Ayu (Plecoglossus altivelis) and Amago (Oncorhynchus masou ishikawae) and fastest flow seen at the slit of weir is less than their burst speed, 3) Roughly 90 % of ayu and amago ascend the fishway in 2 days. Consequently, the finshway is exptected to be of help to ascending fish at high dams and debris barriers.

Analysis of power pools in the deregulated energy market through simulation

The electricity market has changed rapidly in the Northern European countries. Harmonisation of the legislation and trading methods widens the market area outside national limits. Vertical integration among electricity companies is changing the traditional structure of the inner market. Successful business in this new, more volatile market requires sophisticated techniques for identifying new market opportunities and managing the increased risks. We study the new market from the perspectives of regional distributors and power pools. We analyse the trading possibilities and profitability of different kinds of power pools, when a spot market and several new contract structures are available along with existing capacity-based long-term contracts. Different policies for allocating the common benefits of a power pool among its members are compared and a new booking algorithm for balance settlement is introduced. To analyse the operation of different kinds of pools, we use simulation and optimisation techniques.

Phenotypic Design, Plasticity, and Ecological Performance in Two Tadpole Species

This study relates community ecology to phenotypic design in two species of hylid tadpole that share larval habitat on the rocky shoreline of Isle Royale, Michigan. The ecological results indicate that the two species partition a competition-predation gradient on the shore. Pseudacris crucifer is mostly high on the shore at low density in persistent pools with predators (dragonfly larvae, Aeshnajuncea); tadpoles have low individual growth rates and metamorphose late at large body size. Pseudacris triseriata is more variable in growth and development but typically grows more rapidly and metamorphoses earlier. All P. crucifer that attain metamorpho- sis emerge from pools with Aeshna, whereas P. triseriata metamorphose from a mixture of pools with and without predators. A reciprocal transplant experiment showed that both species survived poorly in the upper level pools with predators, which indicates that predation is more important there. The experiment did not show strong competition between the two species in either kind of pool. The phenotypes, including plasticity, of the two species are consistent with their ecological differences. Pseudacris triseriata has traits that functional arguments suggest should assist in processing food: in natural populations it hatches at large size, feeds actively and conspicuously, and has a relatively round body and small tail muscle and tail fin. Pseudacris crucifer has the opposite suite of characters, which functional arguments suggest favor predator avoidance. The variation in larval habitat correlated with differences in plasticity. In the trans- plant experiment, P. crucifer showed little change in phenotype, whereas P. triseriata reduced activity and increased tail fin and tail muscle size in the presence of Aeshna. This study illustrates that ecological differences in tadpoles correlate with behavioral and morphological phenotypes and that phenotypic traits can be used to predict ecological performance in manipulative experi- ments in natural settings. One of the underlying theses of ecology asserts that we can understand the control of communities in terms of interactions, notably competition and preda- tion, between the component populations. A rich experimental tradition has tested this proposition, focusing on interactions among populations. The impor- tance of causal factors is judged according to the impact on population dynamics, judged by experimentally excluding or adding member species in the community (Gause 1934; Connell 1961; Wilbur 1972). This experimental approach, termed phenomenological, has established the causal bases for an increasing number of natural patterns in communities, including the differences in habitat among closely related species.

Crisis on the Eastern Front, 1941-42: A Comparative Analysis of German and American Newsreel Coverage

CRISIS ON THE EASTERN FRONT, 1941-42: A COMPARATIVE ANALYSIS OF GERMAN AND AMERICAN NEWSREEL COVERAGE ** by Robert E. Herzstein While Joseph Goebbels and his Propaganda Ministry censors were approving the release of the latest Wochenschau, a different sort of newsreel was being readied for public consumption over four thousand miles away. In an unimposing New York office building at 460 West 54th Street, near the Hudson River dockside, a frantic scene took place on the third floor on Monday and Tuesday. The busy staff of Movietone News was preparing one of two weekly newsreels produced by the Fox organization. The crowded, bustling third floor housed all the editors, commentators, technicians and equipment involved in this mammoth undertaking. The great outburst of interest in foreign news since the late 1930s made their task more challenging, but also more rewarding. Negative prints of footage filmed abroad were often sent to New York by chartered air clipper. From the airport they were transported via armored car to the Fox building. Included in the film canisters were "dope sheets," handwritten reports filed by the cameramen, indicating the subject, contents and length of the footage. Fox kept a daily log, a record of all film received.33 By 1941 Movietone News had acquired the reputation as the best and most popular of American newsreels. Nor was Fox modest about boasting of its primacy as "the mightiest of them all." Fox News had begun production back in 1919, and proudly displayed a congratulatory letter from President Woodrow Wilson. In the light of the interventionist impact of later Movietone productions, this represented an interesting and prophetic bit of symbolism. Fox News released its first soundtracked film in 1927, showing Colonel Lindbergh taking off on his historic flight to Paris from ** ThAA l& pasut two oI a. two-pa/it ojüá.cJL The great Soviet counter-offensive against the Army Group Center began about three days before the Japanese attack on Pearl Harbor. During these months after Pearl Harbor, Americans, shocked but determined to win, directed most of their attention to the Pacific theater of war. They had been following reports of determined Soviet resistance with increasing interest, but for the monent the Axis threat seemed greatest in the Far East and the Pacific. From the viewpoint of American public morale, the Russian offensive was quite promising, however. Soviet Russia , now a de facto ally, had also been attacked without warning, and after stunning early defeats had rallied her forces and taken the offensive . Newsreel producers realized by January 1942 that this analogy might encourage Americans depressed by the dreary news from the Philippines , or apprehensive about further Japanese attacks on Pearl Habor, or even against the West Coast. Movietone News, like other American newsreel firms, faced real dilemmas in depicting the crisis on the Eastern Front. The United States was not permitted to station newsreel film crews in the Soviet Union. Exceptions might sometimes be made for a state visit or a special interview, but not for battle footage—which is what Americans wanted to see. The quality of the Soviet film was uneven; it was subject to severe censorship, and five to ten weeks might elapse between the original filming and presentation on American screens (sometimes ten to twelve weeks). Film was generally shipped to the United States via Great Britain. Because of these problems, the War Department, with the cooperation of 36 companies such as Movietone, Universal, and Paramount, required that the great newsfilm companies assist each other by facilitating the delivery and showing of foreign films. During the Soviet winter offensive, for example, a British Movietone News editorial dope sheet informed Movietone in New York that "Paramount have already shipped this [footage of the Eastern front] and they will service you." Newsreel companies made duplicates of developed footage of the Eastern Front available to one another in a kind of pool. Unlike the Deutsche Wochenschau, which was a state monopoly, American newsreel companies operated in a competitive environment , which at times yielded to mutual assistance.3? Despite the limitations noted above, American newsreel companies managed to produce impressive coverage of the Eastern Front. Two themes dominated Movietone's coverage of the Eastern Front—Allied...

Effect of growth conditions on accumulation of internal nitrate, ammonium, amino acids, and protein in three marine diatoms

The capacity of marine phytoplankton to change their cellular content of nitrate, ammonium, amino acids, and protein in response to different growth conditions was systematically investigated. Cellular concentrations of these compounds were measured in N-starved, N-deficient, and N-sufficient Skeletonema costatum (Grev.) Cleve and in N-deficient Chaetoceros debilis Cleve and Thalassiosira gravida Cleve, both before and after the addition of a pulse of nitrogen. N-sufficient Skeletonema costatum contains high concentrations of protein, large persistent pools of amino acids, and, if it is growing on nitrate, sizeable amounts of nitrate. As it becomes N-starved, the total cellular nitrogen decreases, the internal nitrate and amino acids become entirely depleted, and the protein content is drastically reduced. After nitrogen additions to N-deficient and N-starved cultures, transient pools of unassimilated nitrogen form which can account for a large fraction of newly taken up nitrogen. The size and kind of pool which accumulates is determined by the preconditioning of the cells, the nitrogen compound which is added, and the species identity. The pools which form in S. costatum indicate that nitrate reduction is the slowest step in nitrogen assimilation, the synthesis of protein from amino acids is the next slowest, and the incorporation of ammonium into amino acid is the fastest. However, the rate limiting steps may vary between diatom species. For the first time, measurements of the variation in cellular nitrogen compounds over a wide range of environmental conditions reveal the ability of some phytoplankton to buffer the effects of a changing, and sometimes growth-limiting, nitrogen supply. They accomplish this by utilizing stored internal nitrogen for growth when the external supply is low and by quickly storing unassimilated nitrogen when the external supply is suddenly increased beyond their ability to immediately assimilate it. The accumulation of large pools of unassimilated nitrogen compounds can explain the often observed difference between nitrogen uptake rates and growth rates.

MODIFICATION OF A STREAM BOTTOM AND ITS EFFECT ON THE INSECT FAUNA

Studies of stream bottoms as a factor in the abundance of aquatic insects is usually accomplished by random sampling of different kinds of pools and riffles. Various types of apparatus and methods are used. Ludwig (1922) used the hand-dip method in his studies. The Needham trap (1928) has also been used extensively in the study of rocky riffles. Gersbacher (1937) used the Peterson trap (1911) and the Ekman dredge (1911) for sand and mud bottom pools. At present the United States Bureau of Fisheries one foot trap, described by Surber (1937), is very popular in studying riffles.