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Number of results: 8
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Abstract

Non-point source pollution is a primary cause for concern globally. Various models have been developed to tackle this situation with much emphasis placed on best management practices. This practice has, however, proven to be insufficient to solve the NPS pollution situation. Existing non-point source models are watershed-based and complicated both in operation, parameter estimation and data requirements. A non-point source model is proposed using the concept of the Hybrid Cells in Series model. The model is a three-parameter model made up of three zones, which describes pure advection through time delay in a plug zone, with combined advection and dispersion occurring when the other two zones are considered as thoroughly mixed. The proposed model is tested using synthetic data and fi eld data from the Snake River, Colorado, USA, obtained from literature. Simulations were performed at four sample points; two from the tracer injection point along the Snake River before a confluence and two further downstream after the confluence. A regression analysis was carried out to determine the model’s capability to simulate pollutant transport for the four sampling points. The coefficients of determination are 0.98, 0.94, 0.84 and 0.97 while the standard error for each reach is 2.28E-2, 2.70E-2, 2.32E-2 and 9.35E-3 respectively. The results show good agreement between the measured and the simulated data. The response of the C-t profiles produced by the proposed model for both synthetic and field data demonstrates its ability to effectively simulate pollutant transport in natural rivers subject to non-point source pollution.

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Authors and Affiliations

Joy Adu
1
Muthukrishna Vellaisamy Kumarasamy
1

  1. University of KwaZulu-Natal, South Africa
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Abstract

A brief description of the innovative mathematical method for the prediction of CET – localization in solidifying copper and copper alloys’ ingots is presented. The method is to be preceded by the numerical simulation of both temperature field and thermal gradient filed. All typical structural zones were revealed within the copper and copper alloys’ massive ingots or rods manufactured by continuous casting. The role of thermal gradient direction for the single crystal core formation has been enlightened. The definition for the index describing proportion between volume fraction of the columnar structure and volume fraction of the equiaxed structure has been formulated by means of the interpretation of some features of the liquidus isotherm velocity course. An attempt has been undertaken to apply the developed mathematical method for the structural zones prediction in the rods solidifying under industrial conditions. An industrial application has been shown, that is, it was explained why the innovative rods should be assigned to the overhead conductors in the electric tractions.
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Authors and Affiliations

P. Kwapisiński
1
ORCID: ORCID
W. Wołczyński
2
ORCID: ORCID

  1. KGHM Polska Miedź S.A., M. Skłodowskiej-Curie 48, 59-301 Lubin, Poland
  2. Institute of Metallurgy and Materials Science, W. Reymonta 25, 30-059 Kraków, Poland
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Abstract

Irrigation network maintenance is very important to ensure the function of irrigation run well. Therefore, maintenance fee is necessary to maintain the irrigation network. The problem is the maintenance cost of irrigation network is expensive, the second highest cost after rehabilitation costs. Thus, participation of farmers in irrigation network maintenance is essential. One of participation by farmers is in the form of regular fees. This study aims to determine the number of fees farmers are willing to pay to maintain irrigation networks through the willingness-to-pay approach. This study was conducted in the irrigation area of the Gonggang reservoir in Magetan District. The subject is farmers who use irrigation – the data collection technique used by observation, interview, questionnaire, and documentation. The data analysis technique used is the contingent valuation method with steps (1) determining the hypothetical market, (2) obtaining bids, (3) estimating average willingness to pay, (4) estimating bid curves, and (5) aggregating data. The result shows that the amount of farmers’ willingness to pay the maintenance fees for irrigation networks at Gonggang reservoir irrigation area in Magetan District by using the contingent valuation method is IDR 90,621 (USD 5.45) for each hectare for each planting period with total willingness to pay in the population of IDR 116,188,708 (USD 7,951.59) for each planting period.
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Authors and Affiliations

Cindy Puspitasari
1
ORCID: ORCID
Joko Sutrisno
1
ORCID: ORCID
Ernoiz Antriyandarti
1
ORCID: ORCID

  1. Universitas Sebelas Maret, Faculty of Agriculture, Study Program of Agribusiness, Jalan Ir. Sutami 36 57126 Surakarta, Central Java, Indonesia
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Abstract

The conversation concerns mayor questions in the theory of historical writing, both raised or elaborated in Hayden White’s work. It focuses on the relation between history and its closest others: science and literature, as well as the issue of the function of historical studies. Conversation includes the discussion of the concepts of fiction, figure, fullfillment, figurative and conceptual language, modernism.

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Authors and Affiliations

Jakub Muchowski
ORCID: ORCID
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Abstract

The dynamics of climatic conditions during the Holocene in the Sumba Strait is not well known, compared with in the Indian Ocean. The aim of this paper is to identify the possible Holocene climate dynamics in Sumba Strait, eastern Indonesia by using deep-sea core sediments. A 243 cm core was taken aboard RV Baruna Jaya VIII during the Ekspedisi Widya Nusantara 2016 cruise. The core was analyzed for elemental, carbonate and organic matter content, and abundance of foraminifera. Based on geochemical and foraminifera data, we were able to identify at least six climatic changes during the Holocene in the Sumba Strait. By using the elemental ratio of terrigenous input parameter, we infer to interpret that the precipitation in the Sumba Strait during the Early Holocene was relatively higher compared with the Mid to Late Holocene.

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Authors and Affiliations

Purna Sulastya Putra
Septriono Hari Nugroho
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Abstract

Secure and cost-effective power generation has become very important nowdays. Care must be taken while designing and operating modern steam power plants. There are regulations such as German boiler regulations (Technische Regeln für Dampfkessel 301) or European Standards that guide the user how to operate the steam power plants. However, those regulations are based on the quasi-steady state assumption and one dimensional temperature distribution in the entire element. This simplifications may not guarantee that the heating and cooling operations are conducted in the most efficient way. Thus, it was important to find an improved method that can allow to establish optimum parameters for heating and cooling operations. The optimum parameters should guarantee that the maximum total stresses in the construction element are in the allowable limits and the entire process is conducted in the shortest time. This paper summarizes mathematical descriptions how to optimize shut down process of power block devices. The optimization formulation is based on the assumption that the maximum total stresses in the whole construction element should be kept within allowable limits during cooling operation. Additionally, the operation should be processed in the shortest time possible.
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Authors and Affiliations

Dariusz Rząsa
Piotr Duda
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Abstract

Based on chemical analyses, the quality of ground waters for drinking, agricultural and industrial purposes was deter-mined in Rafsanjan Plain-Iran. Samples for analyses were taken from 22 wells in 2012. Because of high water hardness and total dissolved solids content, water was found to be unsuitable for drinking purposes. Water quality for agriculture was determined with the use of the Wilcox method. Among the analysed water, 10.33% were attributed to C3-S1 class (high electrolytic conductivity and low sodium adsorption ratio), 59.5% to class C4-S1 (very high EC and low SAR) and 30.17% to class C4-S2 (very high EC and medium SAR). 89.67% of studied wells were unsuitable for agriculture. Because of corro-sive water properties all but two wells on Rafsanjan Plain were undesirable for use in the industry. The results of qualitative analyses were presented in GIS and in databases to support making decision and management of groundwater on Rafsanjan Plain.

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Authors and Affiliations

Mohammad Hossein Jahangir
Keyvan Soltani
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Abstract

The on-going economic transformation of the Moscow market towards the provision of services and trade requires the revitalisation of many districts. The case study — the Dominion Tower building — shows that solutions in the field of architecture and urban planning of buildings whose construction can be categorised as local architectural intervention into existing urban structure may be decisive in the success of an undertaking aimed at activating urban tissue within the interference area.
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Authors and Affiliations

Wojciech Duliński
1

  1. Cracow University of Technology, Faculty of Architecture, Institute of Architectural Design

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