4,671 research outputs found

    The igneous geology of the Burntisland district

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    The district examined in the course of the research embodied in this paper is the south -eastern part of the county of Fife, lying between the coast towns of Aberdour and Kirkcaldy, and stretching in- land to a roughly semicircular boundary enclosing Auchtertool, Raith and Chapel. The area contained within these limits is approximately thirty square miles, and was mapped on a scale of six inches to the mile, thus embracing the major portion of Sheet 36 and all of Sheet 37 of the 1864 edition of the maps of the Geological Survey on that scale. The revision of the area lately commenced by the Survey will, on account of an alteration in the numbering of the maps, be indicated on part of Sheets 35 and 39, and all of Sheet 40. The results of the present examination of the igneous geology of the area are reproduced at the end of this paper on a scale of two inches to the mile, thus reducing the map to the minimum size consistent with the distinct indication of the rock types represented.The object of this investigation was to examine the microscopic characters and field relation- ships of the igneous rocks which have made the coastal part of this region for long a classic ground for the study of Carboniferous Puy phenomena. As is indica- ted in the next section, previous investigations had been confined largely to generalised descriptions of field occurrences and characteristics. Apart from the preparation of a detailed record, it was hoped that the great thickness of lava -flows to the north- east of Burntisland might yield to a process of zonin that a thorough acquaintance with their types might make the identification of intrusions more readily possible, and that further information might be gained regarding the relation of the volcanic necks to the general scheme. Finally it was desirable that the position of the South Fife vulcanicity should be shown with regard to the similar outbreaks in adjacent areas.As -a result of this investigation, the following points are considered to be established and to represent an advance in the knowledge of the igneous geology of the area.Necks: Eleven previously known necks have been systematically described and a new one located to the east of Aberdour. From the boulders found in the agglomerate of these necks no evidence has been found that any of them are younger than the Lower Carboniferous. From its inclination to the adjacent lava-flows the pipe at King Alexander's Craig may be of later date than the others.Lava -flows: Earlier generalised descriptions and some scattered petrographical notes have been replaced by a detailed examination. The rocks have been identified as basalts of the Dalmeny and Hillhouse types. A third variety has been located and described under the name "basalt of the Kinghorn Type ". The result of this classification of the rocks of the lava -flows on the coast section has been to establish a series of zones on broad lines, and this has been applied to the inland exposures with success. In the variation of the lavas there is a tendency towards decreasing basicity in the later members. Analcite has been determined as a fairly constant minor accessory. Two . of th south of Seafield previously regarded as lava -flows have beet remapped as intrusions, and a similar alteration has been made in the case of several of the exposures in the Raith Mass as well as the long ridge of Pirniss Plantation.Intrusions: The nature of these rocks has been determined by petrographic examination for the first time. They include basalts of the Dalmeny and Hillhouse types, two varieties of teschenites, olivine dolerites, non-olivine-bearing non-olivine-bearing dolerites and quartz dolerites. A number of new occurrences have been mapped and several old ones interpreted differently. Throughout the larger intrusive masses there has been differentiation into a lower zone rich in olivine, a middle zone with both olivine and augite well represented, and an upper strongly felspathic zone.From their arrangement in the field, the order which the intrusions followed seems to have been basalts first, then dolerites, and finally quartz dolerites. It is suggested that the time of their development may have been confined within the limits of the Carboniferous period

    The geology of the Highland Border from Tayside to Noranside

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    1. The Highland Border Series: The rocks previously mapped as Margie Grits have been examined microscopically and are shown to resemble very closely those from other localities. In the R. Prosen there has been found a new group of fine grits, black shales, and chert,which are devoid of fossils but probably belong to the older Black Shale- Jasper Series.2. The Lower Old Red Sandstone: A petrological examination of the lava - -form rocks has shown them to belong to various sub- -divisions of the andesite and basalt families. The well- known "Lintrathen porphyry" is found to be a dacite and also a lava flow with a wide - spread occur- -ranee at one stratigraphical horizon. An investigation of the conglomerates has shown their reliability as stratigraphical indices, and a definite rhythmic variation in their composition has been demonstrated, upon which an interpretation of the conditions of their accumulation can be based. The tuffs and sandstones show a closely similar varia- -tion in composition.3. The Upper Old Red Sandstone: What may be a remnant of Upper Old Red Sandstone sediments has been found among the Margie Grits near Auchnacree.4. The Serpentine Belt: The rocks of the belt contain the remains of three types of ultrabasic igneous rock, HARZEURGITE, SERPENTINE-PEGMATITE, and 1)UNITE, and probably represent one plutonic intrusion; together with a smaller quantit of highly decomposed tuffs resembling schalsteins.5. Intrusions: Most of the intrusive igneous rocks are N.E. - -S.W. dykes of tholeiitic character, identical with the Salen type tholeiite from Mull. One sill near Bridge of Cally is probably associated with these rocks, re- -presenting a slightly-different phase of the vulcanic- - ity which may be of Carboniferous age. The dyke at Auchnacree is a pyroxene -basalt and may be connected with the igneous activity of Old Red Sandstone times.6. Sequence: A stratigraphic,al sequence of the Lower Old Red Sandstone rocks has been worked out on the field evidence evidence, and it has been found that the order and grouping is similar to that derived from the Kincar- dineshire rocks by R. Campbell. The nomenclature of that author is therefore employed.7. Tectonics: The investigation has revealed the existence' of a major Highland thrust with a minor one to the north, both of them being steeply inclined upthrusts from the north -west. Estimates of their magnitude are given. Beyond is a normal fault with its downthrow to the south -east. The rocks of the serpentine belt are bounded both to the south -east and to the north- west by planes of dislocation, evidence of contact metamorphism by the serpentine on the country rock being absent. The serpentine- schalstein complex is therefore thought to be older than the Lower Old Red Sandstone. There is a second group of dislocations - dip faults - cutting the Highland Boundary area in a direction N.N.E. - S.S.W. The Old Red Sandstone rocks lie in synclines elongated approximately parallel to the major thrust and fault lines, and in the north-westerly area overlie/ 163 . overlie immediately a denuded halradian schist floor. In the middle and more easterly areas anticlinal folds occur in close proximity to the main Highland Boundary Thrust.8. The glaciation of the region has left extensive relics: New striae and roches moutonnées are recorded and various kames are noted. A series of marginal drainage channels has been mapped along the fringes of the Grampians, parallel to the main valley of Strathmore, and the possibility of their inter- communication in some cases discussed. Associated with these are certain lakes, but there are many others,at intervals along the course of the present river systems,of probably later date, when the melting snows followed the shortest route to Strathmore and cut deep gorges through the conglomerate ridges

    Selected variables associated with the writing ability of beginning teacher education students

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    This study focused on the writing ability of beginning teacher education students at Iowa State University. Writing samples of 332 students enrolled in their first education course (Education 204 - Foundations of American Education) were collected during the Fall 1981, Spring 1982, Fall 1982, and Fall 1983 semesters. The writing samples were evaluated by the course instructors and by evaluators in analyzing English compositions. Data regarding student demographic and academic characteristics were also collected. The purposes of the study were to determine the degree to which the students\u27 writing ability evaluations correlated with selected student demographic and academic characteristics; to determine if the Education 204 instructors and the English evaluators differed significantly in their evaluation of the Education 204 student compositions; and to determine if student writing ability could be predicted from selected variables;Significant Pearson correlation and t - test values affirmed the hypotheses that significant relationships existed between selected student demographic and academic variables, and that the Education 204 instructor writing evaluations differed from those of the English evaluators. Multiple regression procedures were also used to develop three models designed to predict student writing ability from selected combinations of student demographic and academic variables

    On detection of OFDM signals for cognitive radio applications

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    As the requirement for wireless telecommunications services continues to grow, it has become increasingly important to ensure that the Radio Frequency (RF) spectrum is managed efficiently. As a result of the current spectrum allocation policy, it has been found that portions of RF spectrum belonging to licensed users are often severely underutilised, at particular times and geographical locations. Awareness of this problem has led to the development of Dynamic Spectrum Access (DSA) and Cognitive Radio (CR) as possible solutions. In one variation of the shared-use model for DSA, it is proposed that the inefficient use of licensed spectrum could be overcome by enabling unlicensed users to opportunistically access the spectrum when the licensed user is not transmitting. In order for an unlicensed device to make decisions, it must be aware of its own RF environment and, therefore, it has been proposed that DSA could been abled using CR. One approach that has be identified to allow the CR to gain information about its operating environment is spectrum sensing. An interesting solution that has been identified for spectrum sensing is cyclostationary detection. This property refers to the inherent periodic nature of the second order statistics of many communications signals. One of the most common modulation formats in use today is Orthogonal Frequency Division Multiplexing (OFDM), which exhibits cyclostationarity due to the addition of a Cyclic Prefix (CP). This thesis examines several statistical tests for cyclostationarity in OFDM signals that may be used for spectrum sensing in DSA and CR. In particular, focus is placed on statistical tests that rely on estimation of the Cyclic Autocorrelation Function (CAF). Based on splitting the CAF into two complex component functions, several new statistical tests are introduced and are shown to lead to an improvement in detection performance when compared to the existing algorithms. The performance of each new algorithm is assessed in Additive White Gaussian Noise (AWGN), impulsive noise and when subjected to impairments such as multipath fading and Carrier Frequency Offset (CFO). Finally, each algorithm is targeted for Field Programmable Gate Array (FPGA) implementation using a Xilinx 7 series device. In order to keep resource costs to a minimum, it is suggested that the new algorithms are implemented on the FPGA using hardware sharing, and a simple mathematical re-arrangement of certain tests statistics is proposed to circumvent a costly division operation.As the requirement for wireless telecommunications services continues to grow, it has become increasingly important to ensure that the Radio Frequency (RF) spectrum is managed efficiently. As a result of the current spectrum allocation policy, it has been found that portions of RF spectrum belonging to licensed users are often severely underutilised, at particular times and geographical locations. Awareness of this problem has led to the development of Dynamic Spectrum Access (DSA) and Cognitive Radio (CR) as possible solutions. In one variation of the shared-use model for DSA, it is proposed that the inefficient use of licensed spectrum could be overcome by enabling unlicensed users to opportunistically access the spectrum when the licensed user is not transmitting. In order for an unlicensed device to make decisions, it must be aware of its own RF environment and, therefore, it has been proposed that DSA could been abled using CR. One approach that has be identified to allow the CR to gain information about its operating environment is spectrum sensing. An interesting solution that has been identified for spectrum sensing is cyclostationary detection. This property refers to the inherent periodic nature of the second order statistics of many communications signals. One of the most common modulation formats in use today is Orthogonal Frequency Division Multiplexing (OFDM), which exhibits cyclostationarity due to the addition of a Cyclic Prefix (CP). This thesis examines several statistical tests for cyclostationarity in OFDM signals that may be used for spectrum sensing in DSA and CR. In particular, focus is placed on statistical tests that rely on estimation of the Cyclic Autocorrelation Function (CAF). Based on splitting the CAF into two complex component functions, several new statistical tests are introduced and are shown to lead to an improvement in detection performance when compared to the existing algorithms. The performance of each new algorithm is assessed in Additive White Gaussian Noise (AWGN), impulsive noise and when subjected to impairments such as multipath fading and Carrier Frequency Offset (CFO). Finally, each algorithm is targeted for Field Programmable Gate Array (FPGA) implementation using a Xilinx 7 series device. In order to keep resource costs to a minimum, it is suggested that the new algorithms are implemented on the FPGA using hardware sharing, and a simple mathematical re-arrangement of certain tests statistics is proposed to circumvent a costly division operation

    Gas Exchange and Water Relations of Two Alpine and Two Arctic Tundra Plant Species

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    Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as -15 bars. Since moisture stress affects a number of important physiological processes in plants and since moisture stress may develop in at least some tundra areas, this study was undertaken to determine whether the sensitivity of plant physiological processes to water stress may be one important contributing factor in determining the microsite distribution of different tundra species. The alpine tundra species examined in this study were Deschampsia caespitosa which is typically found in wet meadow habitats and Geum rossii, a species which ranges from wet meadow to exposed fellfield habitats. The arctic tundra species investigated were Dupontia fischeri which is restricted mainly to wet meadow areas and Carex aquatilis, a species ranging from wet meadows to drier, more exposed areas. For both the arctic and al pine tundra species, though the photosynthetic capacities of the tundra species restricted mainly to wet meadow areas were higher under conditions of low moisture stress, the wider ranging tundra species were able to maintain greater photosynthetic capacity as soil moisture stress increased. Although the depression of photosynthesis with water stress in these tundra species could be partially attributed to reduced stomatal aperture, with decreased soil water potential most of the decline of photosynthesis was due to a greater non-stomatal or residual resistance, indicating a direct impact of water stress on the photosynthetic apparatus. Dark respiration did not increase with enhanced water stress. Thus, although photorespiration may have increased, increased mitochondrial respiration is unlikely involved in the depression of net photosynthesis. The wet site species typically exhibited higher photosynthesis/transpiration ratios for photosynthesis at low soil moisture stress levels; however, as soil moisture stress increased, the wider ranging species generally maintained higher photosynthesis/transpiration ratios. At high soil water potentials stomata of the species restricted typically to wet meadow tundra areas did not appear to undergo a closing response until the bulk leaf water potential decreased; however, reduced stomatal aperture of the tundra species with a wider distribution was noted before leaf water potential dropped. Although the stomatal mechanism of wet site tundra species exhibited lower degrees of occlusion at high soil water potentials, for the more widely distributed tundra species, Carex and especially Geum, stomatal closure was less pronounced as soil water potential decreased. The ability of Geumto maintain a low liquid phase water transfer resistance from the soil to the leaves as well as to experience relatively small reductions in turgor pressure as moisture stress increased may be important factors in maintaining a favorable leaf water balance over a rather broad range of soil moisture regimes. Differences in turgor pressure response with respect to moisture stress may be associated with differences in cell wall elasticity. Calculations of cell wall elasticity suggest that the wider ranging species have more elastic cell walls as compared with the more rigid, inelastic cell walls in the wet site tundra species. The results of this study show that tundra plants have different gas exchange sensitivities and water relation responses with respect to moisture stress and suggest that these at tributes may be important contributing factors in determining the local distribution of these species

    A compressible boundary layer algorithm for use with SINDA '85

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    It is useful to interface a high-speed-flow solution and SINDA to analyze the thermal behavior of systems that include both conduction and high speed flows. When interfacing a high-speed-flow solution to SINDA, it may be necessary to include the viscous effects in the energy equations. Boundary layer effects of interest include heat transfer coefficients (including convection and viscous dissipation) and friction coefficients. To meet this need, a fast, uncoupled, compressible, two-dimensional, boundary layer algorithm was developed that can model flows with and without separation. This algorithm was used as a subroutine with SINDA. Given the core flow properties and the wall heat flux from SINDA, the boundary layer algorithm returns a wall temperature to SINDA and boundary layer algorithm are iterated until they predict the same wall temperature

    Reactions on the bone marrow in anaemia, with special reference to gelatinous degeneration

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    The report comprises:-A. A short account of the Literature on Gelatinous Degeneration with a list of references.B. An account bf the Examination of Human Bone Marrows removed from the post-mortem room.C. An account of the work on the Experimental Production of Gelatinous Degeneration.D. Tentative Conclusions drawn from the above three sources (A.B. and C.
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