4,171 research outputs found
Mapping performance of irrigation schemes in Turkey
Water is a crucial resource and approximately 70% usage of it in the agriculture sector
in Turkey. Water user associations are in charge of irrigation water management. The core aim
of this study is to assess water user associations have command area more than 1,000 ha (WUAs)
within the districts of DSI (State Hydraulic Works) and to create spatial maps to show the
distribution of the performance indicators used constantly by researchers especially around
Mediterranean countries during the period from 2011 to 2015. Frequency and panel data analysis
are used to figure out the relationship among performance indicators and attributes such as water
diversion type, management type, source of water and district no. Panel data analysis was applied
to examine statistical assessment over time. As a result, current performance indicators show that
excessive irrigation water used due to low technology and management problem. Performance
indicators show high differences among districts due to climate, water resources, and crop pattern.
Moreover, low irrigation efficiency can be increased with a transition to pressurized irrigation
systems, so more are can be irrigated with less water
Ranking irrigation schemes based on principle component analysis in the arid regions of Turkey
ArticleWater is a scarce resource and thus irrigation schemes in arid regions have become
more important. The irrigation sector which uses most of the water resources has to cope with
global warming, disasters and water scarcity around the world, particularly in the Mediterranean
countries, including Turkey. Irrigation schemes, which were built by DSI (State Hydraulic
Works) and whose operation and maintenance management was transferred to water user
associations, play a crucial role in irrigated agriculture in Turkey. In order to improve the
performance, weakness and strengths of irrigation schemes are determined by performance
indicators (system operation, financial and production efficiency) which show the overall
information about them. In the present study, seven irrigation schemes located in an arid region
of central Anatolia were chosen to assess the irrigation performance using principal component,
correlation and cluster analysis while quality index showed the rank of the irrigation schemes.
We found that the average total annual volume of irrigation supply was 7648.58 m3 ha−1
and the
average relative water supply was 1.91 during the 11 years between 2006 and 2016. In this region,
higher inverse correlations were due to using surface irrigation methods (51.3%). As of 2017, the
irrigation schemes have weak water distribution systems, on an average, consisting of 55.5% open
canals, 22.5% canalette and only 10% pipes. According to the quality index, financial and system
operation indicators are more effective than that of production efficiency indicators. In
conclusion, average irrigation ratio (55.68%) can be increased by improving the water
distribution system, and the technology used on both management and farm levels
The effect of anions of transition metal salts on the structure of modified mesostructured silica films and monoliths
Cataloged from PDF version of article.The structure of the preformed LC mesophase of water:transition metal salt ([M(H2O)6]X2):acid (HX):oligo(ethylene oxide) (or Pluronics):tetramethylorthosilicate (TMOS) mixture during hydrolysis and partial polymerization of the silica source is maintained upon further polymerization and condensation of the silica species in the solid state. The liquid mixture in early stage of the silica polymerization could be casted or dip coated to a surface of a glass or silicon wafer to produce mesostructured silica monoliths and films, respectively. The silica species and ions (metal ions and anions) influence the structure of the LC mesophases (as a result, the structure of silica) and the hydrophilic and hydrophobic balance in the reaction media. The silica structure can be changed from hexagonal to cubic by increasing, for example, the nitrate salt concentration in the nitrate salt systems. A similar transformation takes place in the presence of very low perchlorate salt concentration. The salt concentration in the mesostructured silica can be increased up to 1.1/1.0 salt/SiO2 w/w ratio, in mesostructured silica materials by maintaining its lamella structure in P123 and cubic in the CnEOm systems. However, the materials obtained from the P123 systems undergo transformation from lamella to 2D hexagonal upon calcinations. The method developed in this work can be used to modify the internal surface of the pores with various transition metal ions and metal oxides that may find application in catalysis. © 2006 Elsevier Inc. All rights reserved
Model formulations for pickup and delivery problems in designated driver services
Designated driver services use company vehicles to deliver drivers to customers. The drivers then drive the customers from their origins to their destinations in the customers’ own cars; at the destinations, the drivers are picked up by a company vehicle. We typically see teams of drivers assigned to company vehicles serving customers. However, when the drivers may be dropped off by one vehicle and picked up by another, a challenging pick-up and delivery problem arises. In this paper, we study the structural properties of the designated driver problem focusing on the synchronization between company vehicles and drivers. We present a two-index formulations to generate optimal, least-cost routes using a general-purpose solver. We benchmark the two-index formulations against a 3-index formulation and a path enumeration strategy. Based on a set of experiments, we find that the two-index formulation performs well, both in terms of quality and solution time, especially on the formulations with more flexibility in the pairing of drivers to company vehicles. Our computational experiments show that up to 75% cost savings are possible from using a flexible operating strategy as compared to a strategy in which drivers and company vehicles stay together throughout a shift
Model formulations for pickup and delivery problems in designated driver services
Designated driver services use company vehicles to deliver drivers to customers. The drivers then drive the customers from their origins to their destinations in the customers’ own cars; at the destinations, the drivers are picked up by a company vehicle. We typically see teams of drivers assigned to company vehicles serving customers. However, when the drivers may be dropped off by one vehicle and picked up by another, a challenging pick-up and delivery problem arises. In this paper, we study the structural properties of the designated driver problem focusing on the synchronization between company vehicles and drivers. We present a two-index formulations to generate optimal, least-cost routes using a general-purpose solver. We benchmark the two-index formulations against a 3-index formulation and a path enumeration strategy. Based on a set of experiments, we find that the two-index formulation performs well, both in terms of quality and solution time, especially on the formulations with more flexibility in the pairing of drivers to company vehicles. Our computational experiments show that up to 75% cost savings are possible from using a flexible operating strategy as compared to a strategy in which drivers and company vehicles stay together throughout a shift
The relationships of phenotype, genotype and some environmental factors with birth weight in Jersey calves
This study investigated the effects of parity, birth type, gender and birth season on birth weight in Jersey cattle and also investigated the relationships of phenotype and genotype with birth weight. Birth records of the Karakoy farm near Samsun, Turkey for the period from 1998 to 2005 were used as data for this study. Parity (P < 0.001), birth type (P < 0.001) and gender (P < 0.001) had a significant effect on birth weight, whereas season of calving and calving year (P > 0.05) were not significant. The birth weight mean of Jersey calves was 20.87 ± 1.79 kg. Total additive genotypic variance was 14.80, phenotypic variance was 38.95 and heritability of birth weight was 0.38. In planning a selection program to achieve ideal birth weight of Jersey calves, birth type, gender and parity need to be included, with the 4th or later parity been most influential.Key words: Birth weight, estimate of parameter, Jersey, parity, season of birth
Finding least fragmented holdings with factor analysis and a new methodology: a case study of kargılı land consolidation project from Turkey
ArticleLand fragmentation (LF) is a problem
restrain agricultural activities and decrease
mechanization level, production. Land
consolidation (LC) projects are done in the World
as well as Turkey to solve LF issues. Researchers
created indicators to measure land fragmentation
which is important to see success level of LC
projects. The use of these indicators is
controversial or not accurate. The core aim of the
present study is to find new land fragmentation
index and to find least fragmented holding with
factor analysis using the other indicators which
are Simmons, Januszevski, number of parcels,
Shmook and Igbozurike besides new land
fragmentation index. Kargılı Village land
consolidation project in Mersin, Turkey was
chosen as a material. Cadastral data before land
consolidation, was used to calculate value of
indicators, where number of parcels was 932,
total area was 1,741.9 ha, the average parcel size
was 1.9 ha, number of holdings was 542 and the
average parcel size was village had 932 parcels.
Data processing were performed with ArcMAP
10.6.1 and SPSS. A total of 18 holdings were
identified randomly as sample size which were sufficient to carry out factor analysis including
principle component to rank holdings (P < 0.01).As a result, new land fragmentation index found
correlated with others (P < 0.01) and ranking according to new indicator performed better than
ranking considering all indicators. In this context, it is possible to use new land fragmentation
indicator to determine priority areas for land consolidation
TLR2 and TLR4 in Ischemia Reperfusion Injury
Ischemia reperfusion (I/R) injury refers to the tissue damage which occurs when blood supply returns to tissue after a period of ischemia and is associated with trauma, stroke, myocardial infarction, and solid organ transplantation. Although the cause of this injury is multifactorial, increasing experimental evidence suggests an important role for the innate immune system in initiating the inflammatory cascade leading to detrimental/deleterious changes. The Toll-like Receptors (TLRs) play a central role in innate immunity recognising both pathogen- and damage-associated molecular patterns and have been implicated in a range of inflammatory and autoimmune diseases. In this paper, we summarise the current state of knowledge linking TLR2 and TLR4 to I/R injury, including recent studies which demonstrate that therapeutic inhibition of TLR2 has beneficial effects on I/R injury in a murine model of myocardial infarction
- …