scholarly journals Differentiation and Ore-deposits

1920 ◽  
Vol 57 (7) ◽  
pp. 290-299
Author(s):  
R. H. Rastall
Keyword(s):  
Fundamental Problem ◽  
Practical Importance ◽  
Ore Deposits ◽  
Point Of View ◽  
Igneous Rocks ◽  
Theoretical Point ◽  
General Statement ◽  
Blast Furnace Practice ◽  
The Subject ◽  
Genesis Of Ore Deposits

AT the present time most mining geologists appear to be in general agreement on the principle that primary ore-deposits are derived from igneous magmas. Furthermore, it is now almost universally recognized that the segregation and concentration of the metals and their compounds into payable ore-deposits is but part of a larger and more fundamental problem, namely, the differentiation of the igneous rocks, a problem which has exercised the ingenuity of petrologists for many years past and is still by no means solved. Unfortunately most of the speculations and theories put forward in explanation of these phenomena are in the main founded on facts and inferences derived from the study of the silicates; comparatively few petrologists have taken into account the behaviour of the oxidic and sulphidic compounds of the useful metals, which are commonly regarded in the light of rare and accidental constituents of the magma, rather than as having any particular bearing on the point at issue. The most notable exception to this general statement is Vogt, whose work on slags and ore-deposits is of an epoch-making character from the theoretical point of view, as well as of immense practical importance in smelting and blast-furnace practice. However, within the last few years great attention has been devoted by mining geologists to the subject of the genesis of ore-deposits, mainly because of its bearing on the question of persistence in depth or the replacement at lower levels of one ore by another, such as is known to occur in certain cases. It may be suggested, therefore, that the time has now come when it may be possible to attempt to combine the facts hitherto discovered along different lines of research into a coherent whole.

scholarly journals On Kaufmann's theory of the impact of the pianoforte hammer

1920 ◽  
Vol 97 (682) ◽  
pp. 99-110 ◽  
Keyword(s):  
Initial Conditions ◽  
Practical Importance ◽  
Prima Facie ◽  
Point Of View ◽  
Infinite Length ◽  
Modes Of Vibration ◽  
Rigorous Treatment ◽  
The Subject ◽  
Set Up ◽  
The Impact

The theory of the vibrations of the pianoforte string put forward by Kaufmann in a well-known paper has figured prominently in recent discussions on the acoustics of this instrument. It proceeds on lines radically different from those adopted by Helmholtz in his classical treatment of the subject. While recognising that the elasticity of the pianoforte hammer is not a negligible factor, Kaufmann set out to simplify the mathematical analysis by ignoring its effect altogether, and treating the hammer as a particle possessing only inertia without spring. The motion of the string following the impact of the hammer is found from the initial conditions and from the functional solutions of the equation of wave-propagation on the string. On this basis he gave a rigorous treatment of two cases: (1) a particle impinging on a stretched string of infinite length, and (2) a particle impinging on the centre of a finite string, neither of which cases is of much interest from an acoustical point of view. The case of practical importance treated by him is that in which a particle impinges on the string near one end. For this case, he gave only an approximate theory from which the duration of contact, the motion of the point struck, and the form of the vibration-curves for various points of the string could be found. There can be no doubt of the importance of Kaufmann’s work, and it naturally becomes necessary to extend and revise his theory in various directions. In several respects, the theory awaits fuller development, especially as regards the harmonic analysis of the modes of vibration set up by impact, and the detailed discussion of the influence of the elasticity of the hammer and of varying velocities of impact. Apart from these points, the question arises whether the approximate method used by Kaufmann is sufficiently accurate for practical purposes, and whether it may be regarded as applicable when, as in the pianoforte, the point struck is distant one-eighth or one-ninth of the length of the string from one end. Kaufmann’s treatment is practically based on the assumption that the part of the string between the end and the point struck remains straight as long as the hammer and string remain in contact. Primâ facie , it is clear that this assumption would introduce error when the part of the string under reference is an appreciable fraction of the whole. For the effect of the impact would obviously be to excite the vibrations of this portion of the string, which continue so long as the hammer is in contact, and would also influence the mode of vibration of the string as a whole when the hammer loses contact. A mathematical theory which is not subject to this error, and which is applicable for any position of the striking point, thus seems called for.

scholarly journals I.—The Metamorphosis of the Lizard Gabbros

1886 ◽  
Vol 3 (11) ◽  
pp. 481-489 ◽  
Author(s):  
J. J. H. Teall
Keyword(s):  
Mechanical Energy ◽  
Earth Pressure ◽  
Careful Consideration ◽  
Point Of View ◽  
Igneous Rocks ◽  
General Point ◽  
Present Moment ◽  
General View ◽  
Original Rock ◽  
The Subject

If we take a general view of the present position of geological science, we are struck by the fact that, although there is substantial agreement amongst geologists on matters relating to the origin of the rocks usually designated as aqueous and igneous, the greatest diversity of opinion prevails with regard to the circumstances under which the so-called metamorphic rocks have been produced. Every fragment of evidence calculated to throw light on the origin of these rocks, therefore, deserves the most careful consideration. Of recent years special attention has been directed to the effects of mechanical energy in modifying the mineralogical and structural characters of rocks originally formed by aqueous and igneous agencies; and a suspicion has been aroused that it is in this direction that we must look for a solution of many of the problems connected with the origin of the crystalline schists. A visit to the Lizard Peninsula of Cornwall during the present summer has convinced me of the immense importance of this view so far as that district is concerned. That portion of the peninsula which lies south of a line drawn from Porthalla on the east to Polurrian Cove on the west is formed.partly of igneous rocks—such as gabbro, greenstone, serpentine, and granite—and partly of crystalline schists. The igneous rocks, in certain places, become foliated and sohistose and sometimes show a definite banding due to a variation in the relative proportions of the different constituents. In other words they present characters which are usually regarded as distinctive of the crystalline schists. There is, moreover, evidence to show that these characters are mainly the result of a yielding to earth-pressure subsequent to the consolidation of the original rock. At the present moment, having just returned from the district, I am unable to treat the subject from a general point of view with any prospect of success; but it has occurred to me that some details with regard to one of the rocks may not be without interest to members of the Association.

scholarly journals The female characters in Branislav Nušić's and Stefan Kostov's selected comedies

Bastina ◽  
2020 ◽  
pp. 95-109
Author(s):  
Đurđina Isić
Keyword(s):  
Small Town ◽  
Point Of View ◽  
Theoretical Point ◽  
Female Characters ◽  
Modern Age ◽  
The Social ◽  
The World ◽  
The Subject ◽  
Bereaved Family

The paper presents the results of research that included comparative study of the place and role of female characters in selected and representative comedies by Serbian comedigrapher Branislav Nušić (eng. MP, Suspicious person, Mrs Minister, Bereaved family, Dr, Deceased; srb. Narodni poslanik, Sumnjivo lice, Ožalošćena porodica, Dr, Pokojnik, Vlast) and Bulgarian comedigrapher Stefan Kostov (eng. Gold mine, Golemanov, Grasshoppers, Nameless comedy; blg. Zlamnama mina, Golemanov, Skakalci, Komediâ bez ime) in order to find similarities and differences in the process of comedigraphic shaping of female characters in the work of these two authors. The subject of the research was viewed primarily from a literary-theoretical point of view, and the dominant methods of study were comparative and analytical-synthetic. During the research, there was a differentiation of female characters in accordance with their motivational structures, psychological assemblies and the nature of the place and the role they play in the social environment in which they are located. Therefore, we can distinguish female characters who live in the province and who are fully representative of the small-town spirit, female characters who live in the capital and are a symbol of the modern age and female characters who dwell in the capital, but in fact, deeply down still carry a small-town view of the world. The structure of this paper is in line with this distinction. Conclusions made at the end of the study show that the representation of female characters in analyzed comedies of both comedigaphers is highly similar in its nature.

scholarly journals II.—The Fundamental Problems of Petrogenesis, or the Origin of the Igneous Rocks

1911 ◽  
Vol 8 (6) ◽  
pp. 248-257 ◽  
Author(s):  
Franz Lœwinson-Lessing
Keyword(s):  
Physical Chemistry ◽  
Experimental Investigation ◽  
Fundamental Problem ◽  
Genetic Relationships ◽  
Point Of View ◽  
Igneous Rocks ◽  
Detailed Observation

The question of the origin of igneous rocks, their diversity and genetic relationships, represents that fundamental problem of petrography which has been for many years the object of inquiry for petrologists as well as for geologists and chemists. Whilst the amount and scope of detailed observation were growing, the methods of experimental investigation improved, and as the eruptive rocks came to be studied from the point of view of physical chemistry, so the petrogenetical horizon became larger and wider. Thus, on the basis of numerous minute and detailed observations were built broad generalizations that gave rise to new problems.

scholarly journals On the inter-crystalline fracture of metals under prolonged application of stress (Preliminary paper)

1919 ◽  
Vol 96 (674) ◽  
pp. 55-68 ◽  
Keyword(s):  
Practical Importance ◽  
Point Of View ◽  
Exact Nature ◽  
Satisfactory Explanation ◽  
Fundamental Interest ◽  
Crystalline Fracture ◽  
Satisfactory Account ◽  
The Subject ◽  
Cartridge Cases ◽  
Type Of Failure

The authors have recently made a series of observations on some cases of inter-crystalline fracture in various metals, occurring as the result of the prolonged application of stress. In explanation of these phenomena they have formulated an hypothesis which appears to afford a satisfactory account of the present observations and to correlate them with other well-known phenomena whose exact nature has, however, hitherto remained obscure. In putting their observations and hypothesis on record at the present stage, the authors are well aware that much fuller experimental investigation of the whole subject is required, and they hope to carry this forward. The evidence now available, however, appears to them to justify preliminary publication, especially in view of the fundamental interest and great practical importance of the subject. The present paper relates to a group of phenomena some of which have long been known, in the case of brass, as “season cracking.” Brass articles which have been manufactured by a process of alternate cold-working and annealing—such, for instance, as cartridge-cases and other articles made by operations of cupping and drawing—sometimes exhibit a tendency, after a period which may vary from a few hours to several years, to undergo spontaneous cracking. The occurrence of this type of failure of brass has been a serious manufacturing difficulty and much study has been given to the subject; as a result, modifications of both the annealing and the drawing processes have been made, which, to a considerable extent, eliminate the trouble. A satisfactory explanation of “season cracking” has not, however, been put forward so far as the authors are aware. From the present point of view, perhaps the most interesting fact which has been observed about "season cracking” in brass is that the fracture—in those cases where its path can be traced clearly among the micro-constituents of the metal—markedly follows the inter-crystalline boundaries. An example of such a crack is illustrated, under a magnification of 100 diameters, in fig. 1, where the inter-crystalline character of the fracture can be clearly traced (Plate 1).

scholarly journals Evaluación formativa para entornos virtuales en áreas de bases de datos [Formative evaluation for virtual environments in the areas of databases]

2015 ◽  
Author(s):  
Lilia Ana Sandoval Pineda ◽  
Jorge Enrique Quevedo Reyes
Keyword(s):  
Formative Assessment ◽  
Virtual Environments ◽  
Formative Evaluation ◽  
Point Of View ◽  
Theoretical Point ◽  
Review Of The Literature ◽  
The Subject ◽  
Assessment Strategies ◽  
Entornos Virtuales

El artículo tiene como objetivo presentar la actualidad de la evaluación formativa en el tema de diseño bases de datos para entornos virtuales, en donde se mencionan las plataformas virtuales con sus estrategias de evaluación convencional para áreas afines con la ingeniería. Entre los principales aspectos en que se centra la revisión de la literatura esta la taxonomía de Bloom, entornos virtuales, plataformas y evaluación formativa. Desde el punto de vista teórico se centra en el tema de diseño de las bases de datos, las metodologías de evaluación y las diferentes alternativas para ambientes virtuales, enfatizando en los recursos y formas como se afrontan en la actualidad. También se tiene en cuenta el papel del estudiante y del docente en el proceso de evaluación y realimentación del aprendizaje. Luego de experimentar y evaluar desde el punto de vista evaluación formativa, tanto las plataformas estándar, como también los proyectos desarrollados por institutos y universidades, se concluye que las plataformas ni siquiera tienen en cuenta este tipo de evaluación y los resultados obtenidos por proyectos particulares no son suficientes para cubrir un proceso real y completo de este tipo de evaluación.Palabras Clave: Entorno Virtual, Evaluación formativa, Diseño de base datos.This article aims to present the current of formative assessment for the subject of database design for virtual environments where virtual platforms mentioned with conventional assessment strategies for areas related to engineering. Among the main issues focused review of the literature is Bloom's taxonomy, virtual environments, platforms, and educational assessment. From the theoretical point of view focuses on the design theme of the databases, assessment methodologies and the different alternatives for virtual environments, emphasizing resources and forms as encountered today. It also takes into account the role of the student and the teacher in the process of assessment and feedback of learning. After experimenting and evaluating from the point of view formative assessment, both standard platforms, as the projects developed by colleges and universities, it is concluded that the platforms do not even take into account this type of assessment and the results obtained for particular projects, not sufficient to cover actual and complete a process of this type of assessment.Keywords: Virtual Environment, formative evaluation, Designed data base

Conflict management as an organizational capacity: survey of hospital managers in healthcare organizations

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Walter Vesperi ◽  
Marzia Ventura ◽  
Concetta Lucia Cristofaro
Keyword(s):  
Conflict Management ◽  
Organizational Capacity ◽  
Point Of View ◽  
Theoretical Point ◽  
Healthcare Organizations ◽  
Content Type ◽  
Conflict Style ◽  
Hospital Managers ◽  
The Subject ◽  
Study Offer

Purpose The purpose of this paper is twofold. The first objective is to outline the main theoretical framework on the conflict style phenomenon; the second purpose is to understand the conflict style in a sample of Medical Health Manager. Design/methodology/approach The authors based this research on qualitative-quantitative analysis. This study starts with a survey questionnaire as a method to collect quantitative data. Therefore, the authors conducted a survey on the style of conflict management of hospital managers with subordinates. A modified version of the Rahim Organizational Conflict Inventory II (ROCI II) (Rahim, 1983) – Module B is used. This instrument is composed of 28 entries. Findings The results of this study offer a double perspective. From a theoretical point of view, the results highlight the main theoretical references related to conflict management. In particular, the main currents of study and the results of empirical evidence have been identified within organizational theory. The empirical part of this study, instead, offers a survey, carried out through the administration of the ROCI II – module B questionnaire. Originality/value This paper offers interesting food for thought on conflict management. In particular, it offers theoretical references on the subject and on the validation of the ROCI II - Form B model, in health organizations.

Scandinavian pancake constructions as a family of constructions

2014 ◽  
Vol 1 (2) ◽  
pp. 171-196 ◽  
Author(s):  
Tor Arne Haugen ◽  
Hans-Olav Enger
Keyword(s):  
Classical Problem ◽  
Point Of View ◽  
Theoretical Point ◽  
Specific Level ◽  
The Subject ◽  
Corpus Data ◽  
Construction Type ◽  
Empirical Point ◽  
Plural Subject ◽  
First Time

This paper deals with a classical problem in Scandinavian grammar, so-called ‘pancake sentences’, nicknamed after examples like Pannekaker er godt ‘Pancakes are good’ where there seemingly is disagreement between the plural subject and the predicative adjective in the neuter singular. Our aim is twofold. From the theoretical point of view, we shall argue that there are advantages with a construction-based approach, and that such an approach is superior to previous analyses within various generative frameworks.The main reason for this is that the data require generalizations over combinations of subjects and predicative adjectives at a rather specific level. From a more empirical point of view, we shall argue that Scandinavian displays a range of different, but related pancake constructions. For the first time, corpus data are brought into the debate. We show that a construction type that has not received much attention previously is in fact the most frequent type, namely constructions where the subject is a deverbal noun.

scholarly journals Management of Green Intellectual Capital: Evidence-Based Literature Review and Future Directions

2021 ◽  
Vol 13 (15) ◽  
pp. 8349
Author(s):  
Paula Benevene ◽  
Ilaria Buonomo ◽  
Eric Kong ◽  
Martina Pansini ◽  
Maria Luisa Farnese
Keyword(s):  
Literature Review ◽  
Intellectual Capital ◽  
Point Of View ◽  
Evidence Based ◽  
Theoretical Point ◽  
Future Directions ◽  
Increasing Trend ◽  
Management Concept ◽  
The Subject ◽  
Mediation Moderation

This paper presents a systematic, evidence-based review of Green Intellectual Capital (GIC) management, a construct first introduced in 2008 and increasingly recognized as a management concept in recent years. This review covers the literature on GIC from 2008 to 2020 and addresses the role played by intellectual capital as a framework to promote sustainability in organizations. With the aim of clarifying our knowledge on the application of the GIC paradigm, this paper reviews the findings on the outcomes achieved by organizations that adopt the GIC paradigm, the antecedents and possible mediation-moderation factors that enhance this process, and the contexts in which such outcomes emerge. Findings show that GIC offers a significant framework for promoting sustainability in organizations. However, even though this study underlines the increasing trend of GIC, there remains very little reliable data on the subject, particularly addressing the role played by GIC as a framework to promote sustainability in organizations. This literature review is valuable for both researchers and practitioners. From a theoretical point of view, it allows one to synthesize the outcomes of GIC to better delineate how it affects organizations and the environment. From a practical point of view, opening a debate about the actual outcomes of GIC allows one to overcome the theory–practice divide, making the value of GIC more accessible to practitioners and managers and pushing them to opt for a green shift in their organizations.

scholarly journals Autoeficácia e autorregulação acadêmica contribuindo para a previsão da evasão escolar

2014 ◽  
Vol 3 (2) ◽  
Author(s):  
Demerval Rogério Masotti
Keyword(s):  
Self Efficacy ◽  
Self Regulation ◽  
Field Research ◽  
Point Of View ◽  
Economic Consequences ◽  
Educational Institutions ◽  
Theoretical Point ◽  
The People ◽  
The Social ◽  
The Subject

O construto autoeficácia está relacionado às crenças desenvolvidas pelos indivíduos em relação às ações que confiam poder realizar com sucesso em áreas específicas. É também de grande relevância nos processos de autorregulação dos sujeitos, sendo tais conceitos analisados em diferentes contextos, dentre eles o ambiente educacional, com o propósito de avaliar o comportamento dos estudantes diante dos desafios escolares. A evasão escolar é outro importante aspecto que merece destaque nos processos de avaliação institucional na área de educação, em virtude das consequências sociais, acadêmicas e econômicas. Assim, o presente estudo objetivou investigar conceitos referentes à autoeficácia e à autorregulação acadêmica, a fim de verificar se esses fatores contribuem para prever a evasão escolar, e auxiliar no planejamento de intervenções que possibilitem minimizar a evasão dos alunos. As análises indicaram que tanto a autoeficácia quanto a autorregulação acadêmica tratam-se de variáveis significativas, sendo que, do ponto de vista teórico, representam importantes preditores para a evasão dos estudantes. Portanto, o propósito da pesquisa foi alcançado, mas devido às limitações deste estudo que se baseou apenas em fontes bibliográficas, recomenda-se a realização de novas investigações que contemplem pesquisas de campo em diferentes instituições de ensino, a fim de aprofundar a compreensão sobre o assunto. Palavras-chave: Autoeficácia. Autorregulação Acadêmica. Evasão Escolar. SELF-EFFICACY AND ACADEMIC SELF-REGULATION CONTRIBUTING TO PREDICTIONOF THE ESCOLAR EVASION Abstract: The self-efficacy construct is related to beliefs developed by individuals in relation to the actions that trust can perform successfully in specific areas, it is also of great importance in the processes of academic self-regulation of the people, these concepts have been analyzed in different contexts, including the environment educational, in order to evaluate the behavior of students facing school challenges. The school evasion is another important aspect that deserves attention in institutional assessment processes in the education area, because of the social, academic and economic consequences. Thus, the present study aimed to investigate concepts related to self-efficacy and academic self-regulation to verify if these factors contribute to predict school evasion, and assist in planning interventions that enable minimize the evasion of the students. The analysis indicated that both self-efficacy and academic self-regulation are significant variables, and the theoretical point of view is important predictor for school evasion. Therefore, the purpose of the study was achieved, but due to the limitations of this study that was based only on literature sources, it is recommended to conduct further investigations that include field research in different educational institutions, to deepen understanding about the subject. Keywords: Self-Efficacy. Academic Self-Regulation. School Evasion.

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