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[en] Shell and Tube type Oil Cooler is widely used for hydraulic presses, die casting machines, generation equipments, machine tools and construction heavy machinery. Temperature of oil in the hydraulic system changes viscosity and thickness of oil film. They have a bad effect to performance and lubrication of hydraulic machinery, so it is important to know exactly the heat exchanging efficiency of oil cooler for controlling oil temperature. But most Korean manufacturers do not have test equipment for oil cooler, so they cannot carry out the efficiency test of oil cooler and it is impossible to verify its performance. This paper includes information of construction of necessary utilities for oil cooler test and design and manufacture of test equipment. One can select the optimum product by obtaining performance data through tests of various kinds of oil coolers. And also the paper developed a program which can be easily used for design of 2D and 3D drawings of oil cooler
[en] Power consumption in the oil mixing process is very much affected by the impeller design. Minor modification on the impeller design might result in better mixing and less energy consumption. This paper reports an early stage of applying the observation technique to modify three standard impellers, namely the Pitched blade turbine impeller, the CHEMSHEAR impeller and the Vertical Flat-Blade Turbine Impeller. The advantages and disadvantages of these three impellers were analyzed; accordingly minor modification on the impeller design is adopted. The CFD tool is used to evaluate one of the modified impellers; results indicated that the modified impeller achieves better fluid dispersion.
[en] This study examines the growth, conservation, neutrality and feedback hypotheses for 49 countries during the period from 1970 to 2010 using panel causality analysis: this technique accounts for both dependence and heterogeneity across the countries. The results provide evidence as to the direction of causality between oil consumption and output and are consistent with the neutrality hypothesis for 24 countries, the growth hypothesis for 5 countries, the conservation hypothesis for 13 countries, and the feedback hypothesis for 7 countries. The findings provide important policy implications for the 49 countries under study. - Highlights: ► Bootstrap panel causality for 49 countries. ► Examines the “growth, conservation, neutrality and feedback” hypotheses for 49 countries during the period from 1970 to 2010.
[en] This paper presents the comparative study of design efficiency of two different designs of agarwood extracting oil machines by performing using the Design for Manufacturing and Assembly (DFMA) method. The DFMA method was used as it is a well-established technique for improving the efficiency of the product leading to minimizing production costs. It also shortens product development time by reducing the number of components in a product. The study used two different designs of agarwood extracting oil machines as a case study. The result shows that the percentage of the design efficiency of existing design model 1 is 9.25%, whereas it is 15% of redesign. Thus, the redesign model 2 is much better as compared to existing design model 1 in terms of its assembly operation and design efficiency. Therefore, the redesign model 2 is greener than existing design model 1. Therefore, the application of the DFMA method to enhance the development of a agarwood extracting product has been proven to be highly useful in the design work. (paper)
[en] This article outlines a new approach to reliability, availability, maintainability, and safety (RAMS) engineering and management. The new approach covers all phases of the new product development process and is aimed at producers of complex products like safety instrumented systems (SIS). The article discusses main RAMS requirements to a SIS and presents these requirements in a holistic perspective. The approach is based on a new life cycle model for product development and integrates this model into the safety life cycle of IEC 61508. A high integrity pressure protection system (HIPPS) for an offshore oil and gas application is used to illustrate the approach.
[en] Topmetal-II"−, a direct charge sensor, was manufactured in an XFAB 350 nm CMOS process. The Topmetal-II"− sensor features a 72 × 72 pixel array with an 83 μm pixel pitch which collects and measures charge directly from the surrounding media. We introduce the implementation of the circuitry in the sensor including an analogue readout channel and a column based digital readout channel. The analogue readout channel allows the access to the full waveform from each pixel through a time-shared multiplexing. The digital readout channel records hits identified by an individually settable threshold in each pixel. Some simulation and preliminary test results are also discussed
[en] This paper studies co-movements between world oil prices and global prices for corn, soybean and wheat using copulas. Several copula models with different conditional dependence structures and time-varying dependence parameters were considered. Empirical results for weekly data from January 1998 to April 2011 showed weak oil-food dependence and no extreme market dependence between oil and food prices. These results support the neutrality of agricultural commodity markets to the effects of changes in oil prices and non-contagion between the crude oil and agricultural markets. However, dependence increased significantly in the last three years of the sampling period, even though upper tail dependence remained insignificant, indicating that food price spikes are not caused by positive extreme oil price changes. These results have implications for policy design, risk management and hedging strategies. - Highlights: ► We study co-movement between food and oil markets through copulas. ► Food prices are neutral to the effects of changes in oil prices. ► Oil price spikes had no causal effect on agricultural price spikes. ► Oil–corn and oil–soybean dependence increased in recent years. ► Food subsidy policies and price controls are unnecessary to avoid extreme oil prices.
[en] Several studies have been carried out to obtain unsaturated fatty acid (UFA) concentrates, due to their nutritional importance in food applications. The aim of this work was to obtain UFA concentrates from bleached cobia (Rachycentron canadum) and Argentine croaker (Umbine canosai) oil by complexation with urea, and to evaluate their physicochemical and thermal properties during processing. The fatty acids found in high amounts in the crude and bleached oils of cobia and Argentine crocker were palmitic, oleic and linoleic acids. Higher percentages of UFA were present in the oils extracted from the visceras, around 69 and 63% for cobia and Argentine croaker, respectively, and after complexation with urea, the percentages of UFA present in both concentrates were around 88%. Through the thermograms it was possible to observe that the UFA concentrates showed a 50% decrease in their maximum degradation temperature.
[es]Se han realizado varios estudios para obtener concentrados de ácidos grasos insaturados (UFA), debido a su importancia nutricional para su posterior aplicación en alimentos. El objetivo de este trabajo fue obtener concentrados de UFA de aceite de cobia decolorado (Rachycentron canadum) y de corvina argentina (Umbine canosai) por complejación con urea, y evaluar sus propiedades fisicoquímicas y térmicas durante el procesamiento. Los ácidos grasos que se encontraron en mayores cantidades en los aceites crudos y decolorados de cobia y corvina argentina fueron palmítico, oleico y linoleico. Los porcentajes más altos de UFA estaban presentes en los aceites extraídos de las visceras, alrededor del 69% y 63% para la cobia y la corvina argentina, respectivamente, y después de la formación de complejos con urea, los porcentajes de UFA presentes en ambos concentrados fueron alrededor del 88%. A través de los termogramas se pudo observar que los concentrados de UFA tuvieron una disminución del 50% de su temperatura máxima de degradación.
[en] An enhanced adaptation to specific environmental conditions could provide higher seed quality and quantity from groundnuts. In this investigation, nine groundnut genotypes and two controls were evaluated for morphological and oil traits in two different Mediterranean locations. The traits of shelling percentage and pod yield indicated significant differences among the genotypes. The highest pod yield was observed for ACG 154 from the subsp. hypogaea var. hypogaea and ACG 107 from the subsp. fastigiata var. vulgaris in the locations of Adana and Antalya, respectively. The genotype ACG 154 also had about 60 g of 100-seed weight, which is desirable for commercial production as a Runner commercial type. Significant differences were recorded for oil yield, palmitic, oleic and linoleic acids in both locations among the genotypes studied. The groundnut genotypes were further evaluated with allele-specific PCR markers for possible SNP mutations in the ahFAD2A and ahFAD2B genes for high-oleic mutants. ACG 14, ACG 154 and ACG 156 had the mutant ahFAD2A allele, while no ahFAD2B allele mutation was found. The statistical model GGE bi-plot was used to identify the ideal and representative location for each genotype according to pod yield performance. The genotypes ACG 107 and ACG 116 presented the highest oil yield and were relatively stable across locations. Therefore, they should be evaluated as candidates for cultivar releases in the two studied climatic areas. In addition, the selected desirable genotypes in this study can be used as parents in hybridization programs to develop populations for future releases.
[es]El maní, teniendo una mejor adaptación a las condiciones ambientales específicas, podría proporcionar una mayor calidad y cantidad de semillas. En esta investigación, nueve genotipos de cacahuete y dos controles procedentes de dos lugares diferentes del Mediterráneo se evaluaron en relación a las características morfológicas y al aceite. Los rasgos de porcentajes de descascarillado y la producción de la vaina indicaron diferencias significativas entre genotipos así como del rendimiento de la vaina. El rendimiento de vaina más alto se observó en ACG 154 a partir de la subsp. hypogaea var. hypogaea y ACG 107 de subsp. fastigiata var. vulgaris en las ubicaciones de Adana y Antalya, respectivamente. El genotipo ACG 154 también tenía aproximadamente 60 por ciento en peso de semilla que es un valor deseable para la producción comercial un mercado tipo. Se registraron diferencias significativas para el rendimiento de aceite, para los ácidos palmítico, oleico y linoleico en ambos lugares entre los genotipos. Se evaluaron además, los marcadores de PCR específicos de alelo para posibles mutaciones de SNP en genes ahFAD2A y ahFAD2B para mutantes de alto contenido de ácido oleico. ACG 14, ACG 154 y ACG 156 tenían el alelo ahFAD2A mutante mientras que no había mutación del alelo ahFAD2B. El modelo estadístico GGE biplot se utilizó para identificar la ubicación ideal y representativa para cada genotipo en el rendimiento de la cápsula. Los genotipos, ACG 107 y ACG 116, tuvieron mayor rendimiento de aceite y eran relativamente estables en todas las ubicaciones, por lo que deberían evaluarse como candidatos para extender los cultivares en las dos áreas climáticas estudiadas. Además, los genotipos deseables seleccionados en este estudio se pueden utilizar como padres en programas de hibridación para desarrollar poblaciones para futuras liberaciones.
[en] In the process of oil and gas production, radionuclides contained in deep waters and rocks are extracted to the surface of the Earth as accompanying substances, thus involuntarily increasing the level of radiation. This radioactivity is due to the presence of natural radionuclides, such as radon, radium and products of their decay. In addition to radionuclides, by-product waste of oil and gas production also contains heavy metals, such as cadmium, lead, zinc and mercury. Azerbaijan has been producing oil and gas for more than 150 years. This led to a change of the natural background radiation in the territories of oil fields. For a long time, it was believed that the so-called ''small doses of ionizing radiation'' (SDIR) did not have any effect on organisms inhabiting these territories. The measures for the prevention of oil and, consequently, radioactive pollution of the environment have been initiated 20-25 years ago due to the introduction of new technologies. The evaluation of the effect of high natural background radiation on living organisms in oil-producing zones seems to be very important issue.