Consolidation of dredged sludge, measured by an acoustic densitometer

1995 ◽  
Vol 46 (1) ◽  
pp. 179 ◽  
Author(s):  
H Verbeek ◽  
JM Cornelisse
Keyword(s):  
Field Study ◽  
Open Water ◽  
Dry Weight ◽  
Theoretical Models ◽  
Sound Waves ◽  
Dump Site ◽  
Side Scan Sonar ◽  
Field Samples ◽  
Maintenance Dredging ◽  
The Impact

A field study was conducted on the Cromstrijen dump site in the Rhine-Meuse estuary to find the risks of open-water dumping by estimating the impact effects and spreading of freshly deposited sludge and the consolidation of dumped material. The site is used to dump sludge of acceptable quality from maintenance dredging of waterways and local harbours. The investigated sludge came from a navigation channel and was dredged and transported by a hopper dredge. On the dump site, a small section was marked in which the dump took place. A field version of an existing laboratory acoustic densitometer was used to take a profile of the dry-weight concentration of the sediment bed as measured by the attenuation of high-frequency sound waves. The instrument was calibrated with the aid of homogenized field samples. The acoustic densitometer was useful for obtaining a profile of the bed density. With an echo-sounder, an attempt was made to evaluate the consolidation of the dumped sludge. The use of side-scan sonar at the dump site showed a crater with steep banks, surrounded by a thin layer of excess sediment extending over 8400 m². This was only 20% of the dumped sludge; the remaining material was transported outside the measurement section as a density current owing to near-bed surge and local bed slope. The results of the field study are compared with those of previous work and with estimates of the rate and area of distortion derived from theoretical models for the movement of a flow with negative buoyancy.

scholarly journals Προς μια αναμόρφωση των διαδικασιών αξιολόγησης των Ευρωπαϊκών Διαρθρωτικών Ταμείων: μαθήματα από την ελληνική περίπτωση

2018 ◽  
pp. 47
Author(s):  
Σωτήρης Πετρόπουλος
Keyword(s):  
Field Study ◽  
Evaluation System ◽  
Theoretical Models ◽  
Direct Impact ◽  
Literature Research ◽  
Structural Funds ◽  
Vast Literature ◽  
Programming Period ◽  
The Impact ◽  
Policy Proposals

The processes and theoretical models for the evaluation of the impact of European Structural Funds in the Member States are an ever changing and enhancing sector. Based on the results of each programming period, a vast literature and many directives have been developed aimed at better recording these effects. The study of the Greek case, through a thorough literature research and especially a robust field study, indicates that despite all the improvements many, mainly indirect in nature, effects are not recorded and therefore no policy proposals covering such deficiencies and rendering the management and evaluation system of the ESF more effective are being formulated. The article concludes on a series of policy proposals for the improvement of procedures with a direct impact towards the amelioration of the management system of European funds.

Interaction Between Warm Model Ice and a Propeller

2014 ◽  
Author(s):  
T. J. Huisman ◽  
R. W. Bos ◽  
J. Brouwer ◽  
G. Hagesteijn ◽  
H. J. de Koning Gans
Keyword(s):  
High Speed ◽  
Open Water ◽  
Theoretical Models ◽  
Ex Situ ◽  
Crushing Strength ◽  
Extreme Loads ◽  
Load Sensor ◽  
The Time Domain ◽  
The Impact

Ships sailing in ice require a propeller that is able to endure both extreme loads and fatigue loads and operate efficiently in ice and open water. Knowledge and descriptions of the physical processes of propeller-ice interaction are essential to model the interaction with its dominant parameters and finally predict the loads. The research described in this paper uses an experimental setup to determine if the crushing strength of ice, or in general a solid, is a dominant parameter in propeller-ice interaction as stated in empirical and theoretical models. Warm model ice, a paraffin based material to be used at room temperature, with ex-situ tested crushing strength, density and elasticity, is supplied to an in-situ model propeller at different rpms. One blade of the propeller is equipped with a six-component load sensor. Impacts are recorded in the time domain and synchronised with high speed footage. The data is analysed to understand and explain the impact behaviour by comparing it with rotational speed, load and footage. Scaling of the warm model ice properties is discussed as well due to density differences between warm model ice and sea ice.

The Effects of Employment Protection legislationon Personnel Policies: A Review of Theoretical Modelsand Empirical results

2014 ◽  
pp. 126-140
Author(s):  
O. Mironenko
Keyword(s):  
Personnel Selection ◽  
Selection Criteria ◽  
Theoretical Models ◽  
Employment Protection ◽  
Empirical Results ◽  
Protection Legislation ◽  
Labour Contracts ◽  
Hiring And Firing ◽  
The Impact ◽  
Personnel Policies

Employers incur costs while fulfilling the requirements of employment protection legislation. The article contains a review of the core theoretical models and empirical results concerning the impact of these costs on firms’ practices in hiring, firing, training and remuneration. Overall, if wages are flexible or enforcement is weak, employment protection does not significantly influence employers’ behavior. Otherwise, stringent employment protection results in the reduction of hiring and firing rates, changes in personnel selection criteria, types of labour contracts and dismissal procedures, and, in some cases, it may lead to the growth of wages and firms’ investments to human capital.

The yield of perennial grass stands on drained organic soils of Steppe

2016 ◽  
Vol 1 (90) ◽  
pp. 92-97
Author(s):  
I.T. Slusar ◽  
V.A. Serbenyuk ◽  
A.N. Gera ◽  
A.P. Solyanik ◽  
A.A. Tarasenko
Keyword(s):  
Zinc Sulphate ◽  
Foliar Application ◽  
Perennial Grass ◽  
Mineral Fertilizer ◽  
Dry Weight ◽  
Research Area ◽  
Organic Soils ◽  
Growth Promoters ◽  
Cobalt Sulfate ◽  
The Impact

Research on the impact of the introduction of micro fertilizers and growth promoters on a background of mineral fertilizer and without N90R45К120 spent on old peat in shallow carbonate floodplain r.Supiy, Yahotyn Kyiv region. Power peat horizon about 60-70 cm, 7,4-7,6 pH of the aqueous extract, stupas schedule 56-60%, density 0,49-0,52 assembly soil, total nitrogen content (%) - 1.9; gross forms of phosphorus - 0,4, potassium 0.2, 20% lime. In experiments studying biological rehoplant, radustym, Biolan, emistim, Jets, humisol, plantafol, radyfarm and micronutrients: copper, boric acid, manganese sulphate, zinc sulphate, potassium humates. Treatment drugs conducted in the spring by spraying mixtures. Space research area of 60 m2, three-time repetition. It is established that the use of growth stimulants and micronutrients in the background N90R45К120 provided the highest yield mixtures of years, against making BIOLan - 9.9 t / ha Radyfarmu - 9.6 t / ha Radostymu 9.3 t / ha dry weight. In areas for making other preparations were intermediate yield growth rates - 0.5 - 2.0 t / ha dry weight. Also good gains herbage yields obtained by making all kinds of micronutrients and growth stimulants in the background without making makrodobryv which was within 5.3 - 6.9 t / ha to control without fertilization - 4.5 t / ha dry weight. In deep peat copper fertilizer (25 kg / ha of copper sulphate or 5 kg / ha pirytnoho cinders) in all zones should be making every 3-4 years, and zinc, cobalt and molybdenum advisable to make time for the growing season, spring, by foliar application in such numbers: ammonium molibdenovokyslyy - 0.3 kg / ha; cobalt sulfate - 3 kg / ha zinc sulphate 0.5 kg / ha or placers these salts should be mixed with major fertilizer.

Administrative Empowerment and its Impact on Creative Thinking: A Field Study in Private Sector Banks in the Kurdistan Region

2015 ◽  
Vol 1 (3) ◽  
pp. 317
Author(s):  
Abdul Wahab Abdul Fatah Alalwsy
Keyword(s):  
Private Sector ◽  
Field Study ◽  
Creative Thinking ◽  
Study Finding ◽  
Kurdistan Region ◽  
Major Study ◽  
The Impact

The aim of this study is to reveals the Impact of managerial empowerment in creative thinking at the private sector banks of Kurdistan Region .the study depends on descriptive and analytical methodize using the practical manner. Study sample consists of employees in (13) banks of the private sector at Kurdistan Region, its amounted (132). a major study finding that there is a significant statistical impact and positive statistical significant correlation between  managerial empowerment and creative thinking ,by its factors, Originality ,Flexibility ,Fluency, Sensitivity to the problems and the ability to analyze .                                                                                                                     

scholarly journals Testing the Effect of Hedge Height on Perceived Safety—A Landscape Design Intervention

2021 ◽  
Vol 13 (9) ◽  
pp. 5063
Author(s):  
Katinka H. Evensen ◽  
Helena Nordh ◽  
Ramzi Hassan ◽  
Aslak Fyhri
Keyword(s):  
Field Study ◽  
Field Experiments ◽  
Landscape Design ◽  
Urban Environments ◽  
Space Management ◽  
Perceived Safety ◽  
Urban Green Spaces ◽  
Outdoor Spaces ◽  
Surrounding Areas ◽  
The Impact

Access to safe, green urban environments is important for quality of life in cities. The objective of this study is to explore the impact of a safety-enhancing landscape design measure on visitors’ experiences in an urban park. Additionally, this paper combines the use of field and virtual reality (VR) experiments, contributing methodological insights into how to evaluate safety measures in green space management and research on perceived safety. In a field experiment (n = 266), we explored whether the height of a hedge along a pathway influenced perceived safety among users. The field study showed that cutting down the hedge improved the perceived prospect of the immediate surrounding areas for female users, which again made them feel safer in the park. We developed a VR experiment for an evening scenario in the same environment (n = 19) to supplement the field study and test the effect of the intervention further. The VR experiment also found a gender effect on perceived safety, with females reporting lower perceived safety, but no effect was shown for the height of the hedge. The results in this study show that environmental attributes such as perceived prospect and concealment should be considered in the design and management of urban green spaces. Additionally, this research demonstrates an approach to conducting field experiments to test the effects of actual design interventions and then further developing these experiments using VR technology. Further research on perceived safety in outdoor spaces is needed to make use of this combined method’s potential.

scholarly journals Transport Properties of Natural and Artificial Smart Fabrics Impregnated by Graphite Nanomaterial Stacks

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1018
Author(s):  
Carola Esposito Corcione ◽  
Francesca Ferrari ◽  
Raffaella Striani ◽  
Antonio Greco
Keyword(s):  
Electrical Conductivity ◽  
Transport Properties ◽  
Low Cost ◽  
Empirical Relationship ◽  
Theoretical Models ◽  
Expandable Graphite ◽  
Easy Method ◽  
Textile Materials ◽  
Fabric Materials ◽  
The Impact

In this work, we studied the transport properties (thermal and electrical conductivity) of smart fabric materials treated with graphite nanomaterial stacks–acetone suspensions. An innovative and easy method to produce graphite nanomaterial stacks–acetone-based formulations, starting from a low-cost expandable graphite, is proposed. An original, economical, fast, and easy method to increase the thermal and electrical conductivity of textile materials was also employed for the first time. The proposed method allows the impregnation of smart fabric materials, avoiding pre-coating of the fibers, thus reducing costs and processing time, while obtaining a great increase in the transport properties. Two kinds of textiles, cotton and Lycra®, were selected as they represent the most used natural and artificial fabrics, respectively. The impact of the dimensions of the produced graphite nanomaterial stacks–acetone-based suspensions on both the uniformity of the treatment and the transport properties of the selected textile materials was accurately evaluated using several experimental techniques. An empirical relationship between the two transport properties was also successfully identified. Finally, several theoretical models were applied to predict the transport properties of the developed smart fabric materials, evidencing a good agreement with the experimental data.

scholarly journals Musik Gamelan Bali Meningkatkan Pertumbuhan dan Produktivitas Tanaman Sawi Pakcoy (Brassica rafa L.)

2018 ◽  
Vol 6 (2) ◽  
pp. 73
Author(s):  
Dewa Putu Yoga Gautama ◽  
I Made Anom S. Wijaya ◽  
I Wayan Widia
Keyword(s):  
Plant Growth ◽  
Plant Height ◽  
High Frequency ◽  
Dry Weight ◽  
Sound Waves ◽  
High Frequency Sound ◽  
Frequency Sound ◽  
Green Leaves ◽  
Mustard Plant ◽  
Canopy Area

Pemberian gelombang suara dengan frekuensi tinggi dapat merangsang mulut daun  (stomata) tetap terbuka, akibatnya laju dan efisiensi penyerapan pupuk meningkat yang bermanfaat bagi tanaman. Hasil penggunaan sonic bloom pada tanaman adalah mampu menstimulir metabolisme sel-sel tanaman, sehingga terjadi peningkatan penyerapan nutrisi dan uap air lewat daun yang berpengaruh pada pertumbuhan dan produktivitas tanaman. Tujuan dari penelitian ini yaitu (1) untuk mengetahui pengaruh pemberian musik Gamelan Bali terhadap pertumbuhan dan produktivitas tanaman sawi pakcoy dan (2) untuk menentukan jenis musik Gamelan Bali yang memberikan pertumbuhan dan produktivitas sawi pakcoy yang terbaik. Penelitan ini menggunakan tanaman sawi pakcoy (Brassica Rafa L.).  Perlakuan yang diberikan  dalam penelitian adalah pemberian musik gamelan bali dengan nuansa musik yang berbeda. Perlakuan 1 menggunakan musik gamelan Angklung, Perlakuan 2 menggunakan musik gamelan Semarpagulingan dan Perlakuan 3 menggunakan musik gamelan Gong Kebyar. Data yang diperoleh dianalis ANOVA dengan program IBM SPSS 20. Variabel yang diamati yaitu tinggi tanaman, luas kanopi daun tanaman, tingkat kehijauan daun tanaman, dan berat kering. Hasil penelitian menunjukan bahwa pemberian musik gong kebyar menghasilkan nilai tertinggi pada variabel tinggi tanaman, luas kanopi daun, tingkat kehijauan daun, dan berat kering yang  masing menghasilkan nilai yaitu yaitu 29,98 cm, 1684 cm2, 186,79, dan 68,61 gr. Pemberian musik memberikan pengaruh yang positif dan berbeda nyata pada pertumbuhan tanaman sawi pakcoy. Semakin tinggi frekuensi musik yang diberikan maka semakin baik pertumbuhan tanaman sawi pakcoy yang dihasilkan.  High frequency sound waves can stimulate the mouth of leaf (stomata) remains opened.The stomata remains open leading to efficient absorption of fertilizer. The purposes of this research were (1) to find out the effect of Balinese instrument music on the growth and productivity of pakcoy mustard plant and (2) to determine the type of Balinese instrument music that gives the best growth and productivity of mustard pakcoy. The treatment of this research was the application of Balinese instrument music with different musical nuances for 3 hours. Treatment 1 was using Angklung instruments music, treatment 2 was using Semarpagulingan instrument music and treatment 3 using Gong Kebyar instrument music. The obtained data was analized by ANOVA with the IBM SPSS 20 program. The observed variables include plant height, canopy area of plant leaf, green leaves level and dry weight. The results showed that Gong Kebyar instrument music application produces the highest value of 29.98 on the height of the plant variables, the widest value of 1684 cm2  on the canopy area variables, the biggest value that is 68,61 gr on the dry weight variables and the largest value of 186.79 on the green leaves level variables. Balinese instrument music application effect to the growth of pakcoy mustard plant. The best plant growth was the plant with gong kebyar instrument music application from all observed variables.

Sign in / Sign up

Export Citation Format

Share Document