2,216 research outputs found
Flexibility in Port Selection: A Quantitative Approach Using Floating Stocks
Ports provide a number of logistical choices concerning storage, onward transport, and postponement. We investigatethe routing flexibility offered by ports with a central location with respect to the hinterland. This flexibilityis investigated using an illustrative case in which a number of alternative strategies are evaluated by means ofsimulation. Detailed cost data was used for the illustrative case. The combination of a simulation model anddetailed cost data allows us to quantify the value of the rerouting flexibility. A combination of using regionaldistribution centers and a European Distribution Center results in the lowest cost per container.supply chain;floating stock;intermodal transport;inventories;port selection
The determination of 4-methyl-2-thiouracil in animal blood, urine and faeces
A method is described for the determination of 4-methyl-2-thiouracil in blood, human urine and hen's excreta. In the determination in the excreta a suspension of these excreta is dialysed for 12â24 hours against acid water and the determination is carried out in this acid water, as always with the aid of Grote's reagent.
This method was applied with good results in later studies on the metabolism of methylthiouracil in poultry
The metabolism of orally administered 4-methyl-2-thiouracil in cockerels
The metabolism of orally administered methylthiouracil (= MTU) was studied by chemical determinations in the excrements, the contents of the digestive tract, blood plasma, muscle tissue and the thyroids. Daily doses of 40, 50, 80, 100 and 120 mg MTU were used. From the results the following conclusions are drawn: 1. About half of the amount of MTU may be recovered from the excrements within 24 hours after the administration; 2. The excretion rate is maximal about 2â6 hours after the administration. Most of the excretion takes place within 12 hours, excretion is almost complete after 24 hours; 3. In blood plasma and muscle tissue the maximal concentrations (2â4 mg%) are reached in 2â5 hours, after which a rapid decline occurs and no or very little MTU may be found after 20â24 hours; 4. Concentrations of MTU in thyroid tissue are markedly higher than those in muscle tissue. The differences, however, are much smaller than those found by other investigators; 5. MTU is very rapidly absorbed from the gastro-intestinal tract. MTU is only excreted by way of the kidneys, no direct passage through the digestive tract into the excrements occurs; 6. No cumulation of MTU in muscle tissue takes place.
All these facts favour the opinion that MTU may very easily penetrate into and be just as readily eliminated from body tissue
Biosphere-Atmosphere Gas Exchange Measurements using Fourier Transform Infrared Spectrometry
Field measurements of biosphere-atmosphere gas exchange are of great importance because they provide the possibility to study greenhouse gas dynamics and its feedback mechanisms in detail. This thesis contributes to the further development of concentration and flux measurement techniques to study biosphere-atmosphere exchange processes, by exploring the possibilities of using an in-situ Fourier Transform Infrared (FTIR)-analyzer for ecosystem research. This instrument is capable of measuring CO2, CH4, N2O, CO, and delta13CO2 simultaneously. It was combined with different flux measurement techniques, such as the flux gradient technique, the ratio-nocturnal boundary layer technique, and the flux chamber technique. The system was used in four different field campaigns and several laboratory studies. This thesis focuses on the use of the system to a) apply and assess different (new) flux measurement techniques, and b) study different flux and ecosystem processes
Evaluation of Innovative Land Tools in Sub-Saharan Africa:
Sub-Saharan Africa is urbanizing rapidly, but most countries lack appropriate tools to manage their urban growth. This creates both risks and opportunities for prospective land holders, resulting in a tangle of insecure land rights and claims under multiple tenure systems. Recently, innovative land tools have been proposed and implemented to formalize land tenure. It is envisaged that tenure security for land holders will increase and in turn contribute to poverty reduction.
This study evaluates such tools in three peri-urban areas in Lusaka (Zambia), Oshakati (Namibia) and Gaborone (Botswana), with a focus on the perspective of the land holders. The author concludes that the tools are to some extent pro-poor, and makes recommendations for further improvements. These innovative land tools are also considered a necessary addition to conventional and administration tools. This study makes valuable reading for academics, policy makers and practitioners within the land administration domain and related disciplines
Biosphere-Atmosphere Gas Exchange Measurements using Fourier Transform Infrared Spectrometry
Field measurements of biosphere-atmosphere gas exchange are of great importance because they provide the possibility to study greenhouse gas dynamics and its feedback mechanisms in detail. This thesis contributes to the further development of concentration and flux measurement techniques to study biosphere-atmosphere exchange processes, by exploring the possibilities of using an in-situ Fourier Transform Infrared (FTIR)-analyzer for ecosystem research. This instrument is capable of measuring CO2, CH4, N2O, CO, and delta13CO2 simultaneously. It was combined with different flux measurement techniques, such as the flux gradient technique, the ratio-nocturnal boundary layer technique, and the flux chamber technique. The system was used in four different field campaigns and several laboratory studies. This thesis focuses on the use of the system to a) apply and assess different (new) flux measurement techniques, and b) study different flux and ecosystem processes
ICT as an Enabler for Innovation Adoption
In this paper we investigate how two online services (a portal and a digital library) may influence the adoption of an innovation. It is known from prior surveys that the installation services branch of the Dutch building industry has a relatively slow adoption rate for innovations. We examine if these two online services can influence the attitude towards the adoption of innovations. From the academic literature we have derived a list of factors that influence the attitude towards adoption by individuals. We limited this project to a number of factors that are commonly referred to as technological factors. Using an online digital library and a custom-built portal, we conducted a field experiment with a post-test only control group design for one particular innovative product (a gas-analysis device); the test was performed using a survey. Our main finding is that the portal has a significant and positive effect towards the adoption of the innovation by an individual. We did not find a significant impact for the use of the digital library. On the basis of this experiment, we propose that online services that offer a high degree of interaction amongst their users are more likely to induce an increase in the willingness of an individual to adopt an innovation.innovation;adoption;digital library;portal;field experiment.
Arrival processes in port modeling: insights from a case study
This paper investigates the impact of arrival processes on the ship handling process. Two types of arrival processes are considered: controlled and uncontrolled. Simulation results show that uncontrolled arrivals of ships perform worst in terms of both ship delays and required storage capacity. Stock-controlled arrivals perform best with regard to large vessel delays and storage capacity. The combination of stock-controlled arrivals for large vessels and equidistant arrivals for barges also performs better than the uncontrolled process. Careful allocation of ships to the mooring points of a jetty further improves the efficiency.supply chain management;logistics;simulation;transportation;case study
Flexibility in Port Selection: A Quantitative Approach Using Floating Stocks
Ports provide a number of logistical choices concerning storage, onward transport, and postponement. We investigate
the routing flexibility offered by ports with a central location with respect to the hinterland. This flexibility
is investigated using an illustrative case in which a number of alternative strategies are evaluated by means of
simulation. Detailed cost data was used for the illustrative case. The combination of a simulation model and
detailed cost data allows us to quantify the value of the rerouting flexibility. A combination of using regional
distribution centers and a European Distribution Center results in the lowest cost per container
- âŚ