On the Transient of Pressure Waves in Ducts for Systems Operating in Industrial Automation

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Arcangelo Messina ◽  
Giosué Rollo
Keyword(s):  
System Modeling ◽  
Practical Interest ◽  
Point Of View ◽  
Finite Volumes ◽  
Pressure Waves ◽  
Transient Pressure ◽  
Industrial Automation ◽  
Global Dynamic ◽  
Study Results ◽  
Experimental Validations

Within the frame of industrial automation, the mechanical power related to pneumatic actuator systems involves air flows along with mechanical component, such as valves, connecting tubes, cylinder chambers and possible linkages in order to finally actuate a specific objective. Gas dynamic of the air flowing into connecting ducts plays a fundamental role in the description of the global dynamic phenomena of these systems. Several studies deal with the dynamics of such pneumatic systems but through streamlined analysis where the influence of pressure-waves propagating in ducts is neglected or poorly described. The related models are even more complex when finite volumes are placed at the ends of connecting lines. In this paper, two different mathematical models describing transient pressure-waves propagating through lines closed by finite volumes are presented. The investigation regards pressure and velocity ranges normally operating in industrial pneumatic systems. Besides the value of new system modeling of different complexity, these models are compared from an analytical and numerical point of view; advantages, disadvantages, weakness, abilities, and inabilities are highlighted and, finally, the relevant analysis is corroborated through experimental validations of wave propagating pressure at fixed positions of ducts. This study results both in the presentation of models of practical interest, as well as in an attempt to provide an elucidation on the need to resort to an accurate model rather than a streamlined one with respect to the geometric and/or operative characteristics of industrial pneumatic systems.

scholarly journals Linkages between Energy Delivery and Economic Growth from the Point of View of Sustainable Development and Seaports

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4255
Author(s):  
Elżbieta Szaruga ◽  
Zuzanna Kłos-Adamkiewicz ◽  
Agnieszka Gozdek ◽  
Elżbieta Załoga
Keyword(s):  
Sustainable Development ◽  
Crude Oil ◽  
Cross Correlation ◽  
Point Of View ◽  
Oil Products ◽  
Modern Approach ◽  
Economic Cycles ◽  
Study Results ◽  
The One ◽  
Oil And Oil Products

This paper presents the synchronisation of economic cycles of GDP and crude oil and oil products cargo volumes in major Polish seaports. On the one hand, this issue fits into the concept of sustainable development including decoupling; on the other hand, the synchronisation may be an early warning tool. Crude oil and oil products cargo volumes are a specific barometer that predicts the next economic cycle, especially as they are primary sources of energy production. The research study applies a number of TRAMO/SEATS methods, the Hodrick–Prescott filter, spectral analysis, correlation and cross-correlation function. Noteworthy is the modern approach of using synchronisation of economic cycles as a tool, which was described in the paper. According to the study results, the cyclical components of the cargo traffic and GDP were affected by the leakage of other short-term cycles. However, based on the cross-correlation, it was proved that changes in crude oil and oil products cargo volumes preceded changes in GDP by 1–3 quarters, which may be valuable information for decision-makers and economic development planners.

Social Intelligence and its Relation to School Adaptation among Female Students with Learning Difficulties from Perspective of Instructors and Teachers in Elementary School in Jeddah: الذكاء الاجتماعي وعلاقته بالتكيف المدرسي لدى طالبات صعوبات التعلم من وجهة نظر مرشدات ومعلمات المرحلة الابتدائية بجدة

2020 ◽  
Vol 4 (47) ◽  
Author(s):  
Omniah Dhaif Allah Al-otaibi, Hadeel Abdullah Akram
Keyword(s):  
General Education ◽  
Social Intelligence ◽  
School Adjustment ◽  
Learning Difficulties ◽  
Correlation Method ◽  
Female Students ◽  
Point Of View ◽  
Years Of Experience ◽  
School Adaptation ◽  
Study Results

This study aimed to reveal the correlation between social intelligence and school adjustment concerning female students with learning difficulties from the perspective of female guides and teachers at the primary level in Jeddah, as well as knowing the level of social intelligence and school adjustment in addition to checking for differences between averages of the degrees of social intelligence and school adjustment among female students from the perspective of female guides and teachers due to the variable type of profession, scientific specialization and years of experience. The sample of the study consisted of (152) guides and teachers where the researcher followed the descriptive correlation method, and the scale of social intelligence and school adaptation (2020) was used by the researcher. The findings indicated a positive relationship between social intelligence and school adaptation among female students learning difficulties and they have an average level in both social intelligence and school adaptation. In addition, there are no differences between the average scoring of social intelligence and school adaptation among female students of learning difficulties from the point of view of female counselors and teachers due to the variable of profession, scientific specialization and number of years of experience. As a result of the study results, the researcher reached a number of recommendations addressed to educational institutions and female teachers and guides of general education schools applied to learning disabilities programs, which contributes to the development of social intelligence and school adaptation for female students with learning difficulties.

Gorald Enell. "Stomach ulcers". Library of the Practical Physician, Vol. 30. Giz. 1929, 123 pages, price 1 p.

1929 ◽  
Vol 25 (5) ◽  
pp. 582-583
Author(s):  
R. Luria
Keyword(s):  
Peptic Ulcer ◽  
Central Europe ◽  
Practical Interest ◽  
Living Conditions ◽  
Point Of View ◽  
Made In ◽  
Stomach Ulcers

The author aims to highlight the "peptic ulcer" (Die Magengeschwrkrankheit), its pathology and therapy from the point of view of a therapist. As you know, in addition to very detailed chapters in large manuals, many separate monographs are devoted to this issue (I will name only Yarotsky, Enriquez et Durand, Ruhman, Balint, F. Ramond, Tagepa from recent works), but the enormous practical interest presented by the doctrine of peptic ulcer makes it useful to cover the issue again; especially interesting are the observations made in a country where living conditions are somewhat different than: in central Europe, in Sweden

To the clinic of infected ulcers of the stomach and duodenum

1927 ◽  
Vol 23 (5) ◽  
pp. 516-523
Author(s):  
S. A. Grosman ◽  
M. M. Brailovsky
Keyword(s):  
Clinical Manifestation ◽  
Surgical Intervention ◽  
Secondary Infection ◽  
Practical Interest ◽  
Point Of View ◽  
French School

We will not touch the controversial question of the role of infection in the genesis of ulcers and will adopt the point of view of the French school (Duval, Roux, Montier, Girault), for which the concept of an infected ulcer is only a concept of a pathological-anatomical and clinical nature, related to the concept of the evolution of an already existing ulcer, depending on its secondary infection. This evolution of the ulcer, in the presence of a new ingredient of infection, creates some peculiarities in its clinical manifestation,-peculiarities which, in suitable cases, can and must be taken into account both in the choice of time and in the choice of method of surgical intervention. Thus, the question under consideration by us has not only theoretical character, but, as we will try to state below, acquires also a certain practical interest.

scholarly journals New Understanding of Transient Pressure Response in the Transition Zone of Oil-Water and Gas-Water Systems

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Wenbin Xu ◽  
Zhihui Liu ◽  
Jie Liu ◽  
Yongfei Yang
Keyword(s):  
Transition Zone ◽  
Outer Boundary ◽  
Water System ◽  
Pressure Response ◽  
Transient Pressure ◽  
Type Curves ◽  
Boundary Type ◽  
Study Results ◽  
Effective Mobility ◽  
Oil Water

Well test analysis requires a preselected model, which relies on the context input and the diagnostic result through the pressure logarithmic derivative curve. Transient pressure outer boundary response heavily impacts on the selection of such a model. Traditional boundary-type curves used for such diagnostic purpose are only suitable for single-phase flow in a homogeneous reservoir, while practical situations are often much more complicated. This is particularly true when transient pressure is derived during the field development phase, for example, from permanent down-hole gauge (PDG), where outer boundary condition such as an active aquifer with a transition zone above it plays a big role in dominating the late time pressure response. In this case, capillary pressure and the total mobility in the transition zone have significant effect on the pressure response. This effect is distinctly different for oil-water system and gas water system, which will result in the pressure logarithmic derivatives remarkably different from the traditional boundary-type curves. This paper presents study results derived through theoretical and numerical well testing approaches to solve this problem. The outcome of this study can help in understanding the reservoir behavior and guiding the management of mature field. According to the theoretical development by Thompson, a new approach was derived according to Darcy’s law, which shows that pressure response in the transition zone is a function of total effective mobility. For oil-water system, the total effective mobility increases with an increase in the radius of transition zone, while for gas-water system, the effect is opposite.

scholarly journals Status of the quality of education and accountability unit in the educational process from the point of view of the principals of Kasbah Al Mafraq schools: واقع الاستفادة من وحدة جودة التعليم والمساءلة في العملية التربوية من وجهة نظر مديري مدارس قصبة المفرق بالأردن

2020 ◽  
Vol 4 (7) ◽  
Author(s):  
Muneera Abdalkareem Alshdefat
Keyword(s):  
Evaluation Criteria ◽  
Educational Leaders ◽  
Educational Process ◽  
Point Of View ◽  
Quality Of Education ◽  
Development Methodology ◽  
Low Degree ◽  
Study Results ◽  
The Status

This Present study aimed at finding out the Status of the quality of education and accountability unit in the educational process from the point of view of the principals of Kasbah Al Mafraq schools To achieve the goal of the study, a descriptive development methodology was developed, which was developed in three areas (evaluation criteria, cooperation and coordination, feedback and incentives) (21) items, and verified their validity and stability, and then distributed to the sample of the study consisting of (167) managers and directors in schools Kasbah Mafraq. The study results showed that the degree of appreciation and the reality of Status of the quality of education and accountability unit in the educational process from the point of view of the principals of Kasbah Al Mafraq schools was at low degree The average of the tool as a whole was (2.00) with a standard deviation of (.55) and at the level of domains, All of them were rated low, with feedback and incentives having the highest average (2.09) followed by evaluation criteria (2.00) and cooperation and coordination (1.90), and the results showed that there were no statistically significant differences in The study sample of the Status of the quality of education and accountability unit in the educational process from the point of view of the principals of Kasbah Al Mafraq schools, according to gender, at the macro level of the instrument and on all dimensions. The study recommended in light of those results the necessity for that efforts should be join efforts to support and deepen the concept of quality of education and accountability, cooperation and coordination between the quality unit of education and accountability and educational leaders, and try to provide incentives and thanks to those who deserve it, to achieve the concept of guidance and support.

scholarly journals The Degree of Effectiveness of The Management of Women in Administrative Empowerment and Its Obstacles at The Branches of Hail University from The Point of View of Faculty Members: درجة فاعلية الإدارة النسائية في التمكين الإداري ومعوقاتها لدى فروع جامعة حائل من وجهة نظر عضوات هيئة التدريس

2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Maysaa hasan muflih BaniHani
Keyword(s):  
Point Of View ◽  
Faculty Members ◽  
Work Team ◽  
First Semester ◽  
Delegation Of Authority ◽  
The Social ◽  
Study Results ◽  
General Average ◽  
High Degree ◽  
The Impact

The purpose of this study was to investigate effectiveness of female administration in the Administrative Empowerment at Hail University branches and its impediments, from the point of view of the faculty members. The researcher used the descriptive analytical approach. The questionnaire was the tool of study and the study sample consisted of (53) of female faculty members at Hail University branches during the first semester 2018- 2019. The results of this study found that the overall degree of administrative empowerment was obtained at a general average (3.93) i.e. high degree and at the dimensional level. Indeed, the work team term was in the first rank with an average of 4.09, and then it comes the delegation of authority with an average of (3.89). The communication term comes at the third level with an average of (3.88) and in the last rank, it comes the motivation of the staff with an average of (3.86) and all of them with a rating of (high). As regard the obstacles in the women administration, the administrative impediments obtained the first rank with an average of (3.87) followed by the personal constraints with an average of (3.76), and then the political impediments with an average of (3.47), and finally the social obstacles with an average of (2.61). For instance, the study showed that there were no significant differences due to the impact of experience years and the impact of scientific qualification. There were some recommendations according to the study results, which were to increase the effectiveness of faculty members and remove obstacles facing them.

scholarly journals Effect of alcohol on bards agrochemical soil properties

2017 ◽  
Vol 19 (74) ◽  
Author(s):  
N. M. Glovyn
Keyword(s):  
Practical Interest ◽  
Integrated Approach ◽  
Ecological Condition ◽  
Modern Technology ◽  
Point Of View ◽  
Nature Protection ◽  
Waste Products ◽  
Economic Point ◽  
Protection Legislation ◽  
Cattle Breeders

The influence of distillery stillage doses on the yield of wheatgrass hay on agrochemical properties of soils in general is considered in the article. The most effective dose of distillery stillage under existing conditions is revealed. Nitrogen is the decisive factor for the yield of the crops. Widespread deficiency of nitrogen represents scientific and practical interest for the agro-chemistry studying transformation of nitrogen in soil-fertilizer-plant system for the purpose of increase in efficiency of crops quality in the biological relation. Increase in the main production of distilleries and conse-quently in waste products of the spirit industry, low demand from cattle breeders on the distillery stillage (feeding of cattle with distillery stillage is precisely connected with seasons, i.e. it is fed, mainly, during the stall period) has led to the fact that nearly 50% of it could not be sold. Development and deployment of new waste-free technologies of production of alcohol will demand a lot of time and expenses, and the unused stil-lage comes to ponds stores daily which are gradually overflowed that endangers the ecological condition of croplands and open reservoirs, adjacent to distilleries. Moreover, long storage in ponds leads it to spoiling, stratification and formation of a ground deposit. Therefore the problem of stillage utilization is very actual now and demands an integrated approach to its consideration as it has to be considered in the economic point of view, and from compliance to requirements of the nature protection legislation. One of the solutions of the problem stillage utilization is its application in agriculture as fertilizer. In Ukraine, the grain bards resources are quite significant, given the volume of alcohol SE Ukrspirt. The volume pislyaspyrtovoyi bards on modern technology is per 1 dm3 alcohol 11 ... 13 dm3 bards. However, it can be stored quickly sour, costly transportation to the consumer. Reset distillery bards in the river leads to significant environmental degradation. It solids accumulate in water pipes and riverbeds, decompose and pollute the environment. To build bards were repositories (filtration fields), which naturally occurs mechanical, chemical and biological treatment of waste. In bioshari formed in a layer of filtration load, the sewage draining into the ground, organic matter biodegradable. This mechanism is similar to the process of composting cut vegetation, household food waste and so on.

Inhibitors of proteolysis and plasminogen of blood serum in parturient women with an uncomplicated course of the postpartum period

1998 ◽  
Vol 79 (2) ◽  
pp. 135-136
Author(s):  
N. N. Semenkov ◽  
V. S. Gorin ◽  
S. G. Zhabin ◽  
L. V. Renge ◽  
N. G. Potekhin
Keyword(s):  
Blood Serum ◽  
Postpartum Period ◽  
Practical Interest ◽  
Point Of View ◽  
Markers Of Inflammation

Recent studies have shown that proteolysis inhibitors can be regarded as markers of inflammation with immunoregulatory properties. From this point of view, the study of inhibitors of proteinases in blood serum of puerperas with an uncomplicated course of the postpartum period is of great scientific and practical interest.

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