Extra Quantity Research Articles

Frequency support by scheduling of variable-speed wind turbines

This paper characterizes optimal control policies for wind farms operated as frequency response services in case of a fault of conventional generators. The frequency support is provided through temporary over-production: when frequency drops, the turbines move from the steady-state operating point and extra power is produced by slowing down the turbines and releasing part of their kinetic energy. The control task is formulated and solved as an optimal containment problem: the time during which an extra quantity of power can be produced, within the set speed constraints for each turbine, is maximized. The solutions are calculated and compared for different assumptions on the electric torque of the turbines.

Large scale extraction of the fruits of Garcinia indica for the isolation of new and known polyisoprenylated benzophenone derivatives

Large scale extraction of the fruits of Garcinia indica was conducted with water extracted hydroxyl citric acid. The marc left after water extraction was extracted exhaustively with methanol and concentrated methanol. The concentrated methanol extract was adsorbed with celite and dried. The dried celite containing the methanol extract was successively extracted with hexane, chloroform and ethyl acetate to get hexane, chloroform and ethyl acetate extract respectively. Column chromatographic separation of hexane extract afforded two new molecules, one polyisoprenylated benzophenone and a new acylphloroglucinol derivative and two known molecule garcinol and isogarcinol. Likewise, chromatographic separation of the chloroform and ethyl acetate extract also yielded extra quantity of garcinol and isogarcinol respectively. Garcinol was isolated as a major compound among all the four molecules isolated from the fruits G. indica.

Coastal lagoons in New South Wales

With the exception of Tasmania, Australia as a whole is deficient in surface waters. There are only a few sizable inland lakes in New South Wales and most of these, certainly the ones around the major population centres along the coast, are water supply reservoirs which are protected and not accessible to the public. There are however, numerous brackish “lakes” along the New South Wales coast many of which are important holiday centres for the population of Sydney, Newcastle and Wollongong. These so called “lakes” are in fact coas tal lagoons. A coastal lagoon is defined by Barnes (1980) as a body of brackish or salt water separated from the adjacent sea by a low lying sand or shingle barrier and these coastal “lakes” certainly fit well into this definition. The literature on the Australian coastal lagoons is sparse and partly inaccessible. The Lake Macquarie study by the CSIRO was by far the most comprehensive and resulted in the publication in 1959 of a series of 12 papers on various aspects of the lagoon’s ecology (Baas Becking, Thomson and Wood, 1959; Spencer, 1959; Baas Becking, 1959; Wood, 1959a, b; Davies, 1959; MacIntyre, 1959; Thomson, 1959a,b,c,d,e). Typically lagoons are shallow with sandy bottoms and are usually fed by one or more short streams. Although the normal freshwater input is not great, floods do occur at irregular intervals due to the relatively large catchment areas surrounding the lagoons. The greatly increased hydraulic gradient generated by the extra quantity of water during floods frequently is sufficient to sweep away the sand barriers, allowing free interchange with the sea. Otherwise the sand barriers, which are constantly being reformed, are quite effective barriers and a lagoon may be isolated from the sea for many years at a time. Under normal conditions, there is very little exchange between the sea and the lagoon so that salinity and water level of the lagoon are functions of rainfall and evaporative loss of water. The extent of salinity fluctuation can be very large. In Tuggerah lakes, during the period 1979-1980 the measured salinity ranged from 20ppt to 42ppt (hypersaline). But salinity as low as 5ppt had been recorded at the end of previous floods (Higginson, 1865). The effect of rainfall on salinity changes can be more dramatic in a smaller lagoon. In Narrabeen Lagoon for example, each major fall of rain can cause steep vertical and longitudinal salinity gradients to be developed due to the rapid input of freshwater from the feeder creeks.

Genetic optimization of fabric utilization in apparel manufacturing

In apparel manufacturing, cut order planning (COP) plays a significant role in managing the cost of materials as fabric usually occupies more than 50% of the total manufacturing cost. Following the details of retail orders in terms of quantity, size and colour, COP seeks to minimize the total manufacturing costs by developing feasible cutting order plans with respect to material, machine and labour. In this paper, a genetic optimized decision-making model using adaptive evolutionary strategies is proposed to assist the production management of the apparel industry in the decision-making process of COP in which a new encoding method with a shortened binary string is devised. Four sets of real production data were collected to validate the proposed decision support method. The experimental results demonstrate that the proposed method can reduce both the material costs and the production of additional garments while satisfying the time constraints set by the downstream sewing department. Although the total operation time used is longer than that using industrial practice, the great benefits obtained by less fabric cost and extra quantity of garments planned and produced largely outweigh the longer operation time required.

Editorial [Hot Topic: Neurodegeneration and Neuroregeneration:Recent Advancement and Future Perspectives (Executive Editor: H.S. Sharma)

Neuroprotection: Non-Neural Cells Regulate Neuronal Functions The term “Neuroprotection” normally denotes rescue of nerve cells. However, the non-neural cells, i.e., glial cells and endothelial cells are equally important for brain function in normal and in pathological conditions [1,2]. The number of glial cells and endothelial cells far exceeds the number of neural cells in the CNS [2,3]. In spite of this fact, most attention is still focused to rescue nerve cells following CNS injuries and the role of non-neural cells in neurodegeneration or neuroprotection is largely ignored. Thus, the term “neuroprotection” is normally misleading as neurons are in the minority in the CNS and their function depends on the survival of non-neural cells and vice versa. To restore the normal function of the CNS by pharmacological manipulation, revival of glial cells and endothelial cell functions are equally important [4-6]. The nerve cell function is largely dependent on the normal endothelial cell and glial function. Thus, it is imperative that in pathological conditions, reducing damage to endothelial cells and/or glial cells by pharmacological agents will improve nerve cell function. Alternatively, glial cells, endothelial cells are all working to maintain and regulate neuronal function in health and disease [7,8]. Taken together, it appears that both the neural and non-neural components of the CNS are working in synergy for maintaining normal brain function and alterations in any neural or non-neural component will have severe impact on CNS structure and function. Blood-Brain vs. Brain Blood Barriers Our CNS is well equipped with the blood-brain barrier that is anatomically located within the endothelial cells of the brain microvasculature [1]. It is assumed that both the luminal and the abluminal cell membranes of the endothelium are equally “tight” to maintain an effective barrier between blood to brain and brain to blood [1,2]. Interestingly, the endothelial cell function and membrane transport from brain to blood (brain-blood barrier) in relation to neurodegeneration and neurorepair mechanisms are still largely ignored [see7,8]. Thus, it is still unclear whether luminal barrier disruption always accompanied with identical damage to the abluminal barrier function. However, there are reasons to believe that when luminal membrane is permeable, the abluminal side is also showing some alteration in the membrane function. A direct evidence to support or reject this hypothesis is still lacking. Studies carried out in our laboratory suggest that hyperthermia induced breakdown of the blood-brain barrier is also associated with a leaky brain blood-barrier [5,9]. Thus, serotonin transport occurs from brain to the blood causing a massive accumulation of the amine in the circulation leading to a generalized and widespread disruption of the blood-brain barrier [9]. This large increase in plasma serotonin is largely prevented by destruction of the serotoninergic neurons into the brain [see 5,9]. This treatment did not allow brain serotonin to increase and thus, the plasma serotonin concentration is much lower resulting in a minor breakdown of the blood-brain barrier in hyperthermia [5]. This suggests that various endogenous substances, e.g., cytokines, growth factors, growth hormone etc. are released from brain in extra quantity following injury that could be transported into the blood stream to have a generalized effect on the cerebral circulation and/or brain function. However, this is entirely a new subject and requires additional investigation in details to achieve better neuroprotection in future. In this volume, the term “Neuroprotection” is employed in its widest sense to include protection of all the “neural” and “nonneural” components of the CNS. This issue highlights the role of non-neural cells; especially the function of endothelial cells and its surrounding glial cells in neurodegeneration and repair process.......

Structural reorganization of the PPy/DBS films caused by the reduction branch of potentiodynamic polymerization

Polypyrrole/dodecylbenzenesulfonate (PPy/DBS) films were synthesized in aqueous solution by cyclic voltammetry. The polymerization carried out at slow scan rates produces two cathodic peaks on the reduction branch. A single reduction peak was obtained at scan rates higher than 50 mV s −1. Two different polymeric structures have been proposed to explain the observed cathodic splitting. Structure I was associated with the organization reached by slow rate electropolymerization processes. Structure II was obtained when I was permanently modified by electrochemical reduction. Under electrogeneration by potential cycling a constant amount of I is generated on every cycle, providing a constant reduction peak A charge. However, the charge involved in peak B, where structure II is reduced, increases with the cycling. Structure I has a lower energetic content than structure II: it is reduced at lesser cathodic potentials than II. Voltammetric and EDX measurements indicated that a main cationic transport occurred during the redox process of the PPy/DBS. However, a certain amount of Na + cations was not interchanged, since they were stabilized inside the polymer, forming ion pairs with an extra quantity of DBS − anions trapped in the polymer matrix during the polymerization process.

The effect of lot sizing rules on order variability

Previous papers have presented the impact of various aspects, such as forecasting techniques, centralising information, and ( s, S) ordering policy, on the variability of orders in a supply chain. In this paper we observe several properties of two traditional lot sizing rules, the Silver Meal (SM) and the least unit cost (LUC) on the variability of orders created by a supply chain channel receiving demand with stochastic variability from its downstream channel. Analytical models have been developed to compare the mean and variance of both order interval and order quantity produced by the two rules under relatively low demand variability. We show that, although the two rules appear to be very similar, they exhibit interestingly different behaviour. The SM rule is shown to produce a series of orders with more stable interval between orders but with more variable order quantities. Conversely, the LUC rule results in more stable order quantities but more variable order intervals. The study also reveals that addition of an appropriate amount of extra quantity to an order could significantly reduce order variability. With an increasing concern on the amplification of order variability in supply chains recently, the results provide interesting insights on the choice of lot sizing rules to be applied by a channel of a supply chain in determining ordering policies.

Application of Binder in Stamp Charge Coke Making

Successful and sustainable implementation of Stamp Charging Technology in Tata Steel has given it an edge over conventional Top Charging Technology in terms of production of superior quality of Blast Furnace grade coke from a wide range of coal base, even permitting use of inferior coals. But, the stability of stamped coal cake and the additional thermal energy necessary to drive the extra quantity of water (3-4 %), added intentionally to the coal blend to impart requisite coal cake strength, have always been the two haunting issues associated with this technology. This paper describes the role of coal tar pitch, used as a binder to the coal blend that not only imparts required strength and stability to the coal cake even at lower moisture level and thereby, reducing energy consumption, but also improves the rheological properties of coal blend that contributes to the quality of coke produced from inferior coals. This paper also describes the laboratory scale experimentation and its results followed by commercial plant-scale trials that confirmed the R & D findings on the use of coal tar pitch.

Evolution of dynamics in the eastern Mediterranean affecting water mass structures and properties in the Ionian and Adriatic Seas

Basin‐wide hydrographic observations performed in the eastern Mediterranean during the past 2 decades attest changes in the thermohaline circulation as well as new aspects concerning the onset and the follow up of the major transient event that occurred at the beginning of the 1990s, i.e., the change of the dense water formation site from the Adriatic to the Aegean Sea. Since 1999, the upper thermohaline circulation has indicated the restoring of the opposite flows of the Atlantic Water and the Levantine Intermediate Water, which were greatly reduced in the period 1987–1995. In the deep layer the comparison between water mass structures observed in 1995, during the mature status of the transient, and those observed in 1999 shows a damping of the event and a regained role of the Adriatic Sea as a primary source of dense waters. Separate calculations of the salt content in the Ionian and in the Levantine Seas show an overall salt redistribution. During 1987–1995 a salt loss of about 25 × 1012 kg was computed for the upper 800 m, constituting only 27% of the salt gain in the deep layer over most of the eastern Mediterranean. On the contrary, during 1995–1999 the restored upper thermohaline circulation caused a salt redistribution between the two basins of about the same amount, but in the opposite sense, while an extra quantity of 12 × 1012 kg was deposited in the deep layer. In addition, calculations of the salt concentration in the convection region of the southern Adriatic reveal a remarkable amount of the salt, not yet totally transferred into the deep layers by its interior dynamics because of mild winters.

Inventory model with a one-time opportunity to order extra items

We study the inventory model with a one-time opportunity to order extra items of a lower purchasing cost. Davis and Gaither had investigated this problem and published in the journal Management Science. There are some improvements that can be achieved. The purpose of this paper is fourfold: Firstly, we point out the well-defined problem in the construction of the inventory model such that we extend from one year plan horizon to several years plan horizon. Secondly, we offer easy methods to derive the objective function. Thirdly, we provide lower bounds to simplify the computation for determining the extra replenishment quantity. Fourthly, we show that there are some questionable numerical results in the examples and prove that the multiplier factor is proportional to the monthly return rate.

Slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry for steelmaking flue dust analysis

A commercial atomic absorption graphite furnace (AAGF), with a self-made adapter and valve system, was used as a slurry sampling cell for electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS). The system was applied to the determination of As, Sn, Sb, Se, Te, Bi, Cd, V, Ti and Mo in steelmaking flue dusts. Experimental conditions with respect to ETV and ICP-MS operating parameters were optimized. Compared to aqueous solutions, slurry samples were found to present better analyte transport. Microgram amounts of Rh were used to reduce the difference in analyte response in sensitivity for aqueous solutions of the tested analytes. No such increasing effect was observed for slurry samples and aqueous standards. An added quantity of Rh acting as modifier/carrier resulted in an increase for the same analytes in matrix-slurry solutions, even the addition of an extra Rh quantity has resulted in a decrease in the signals. The effect of Triton X-100 (used as a dispersant agent) on analyte intensity and precision was also studied. External calibration from aqueous standards spiked with 100 μg ml −1 Rh was performed to quantified 0.010 g/100 ml slurry samples. Results are presented for a certified reference electrical arc furnace flue dust (EAF): CRM-876-1 (Bureau of Analysis Samples Ltd., Cleveland, UK), a reference sample of coke ashes X-3705 (from AG der Dillinger Hüttenwerke, Germany), and a representative sample of EAF flue dust from a Spanish steelmaking company (CENIM-1). For the two reference materials an acceptable agreement with certificate values was achieved, and the results for the CENIM sample matched with those obtained from conventional nebulization solution.

A discrete-time probabilistic inventory model for deteriorating items under a known price increase

A discrete-time probabilistic inventory model for deteriorating items when the supplier announces a price increase of units from some future date is developed here. Units purchased just before the price increase becomes effective are available at the present lower rate. The problem is to determine an extra large quantity to be procured just before the price increase becomes effective. This is a time decision problem. The model is developed under the conditions of instantaneous delivery, no shortages and a constant fraction of on-hand inventory deterioration. Appropriate formulae have been obtained to procure the gain and the large quantity to be purchased just before the price increases. An example is given to analyze the model developed.

Consumer perceptions of bonus packs: an exploratory analysis

Presents an account of a study which examined consumer perceptions of bonus pack offers. A bonus pack is a manufacturer’s sales promotion technique of giving the buyer an extra quantity of a product at the usual price (e.g. an extra 6 oz free; buy four, get one free). No scholarly research on bonus packs was uncovered by the literature review. Hence, this study represents, perhaps, one of the earliest scholarly works on bonus packs. The research tested two offers of VaselineIntensive Careskin lotion (one offer was of 80 percent, the other of 60 percent more free). Consumer responses ‐ their belief in the offers (quantities and prices claimed), their perceptions of the manufacturer and of the value of the deal, and their purchase intentions ‐ were measured.The measures were further analyzed by types of user (light versus heavy) and buyer (regular versus infrequent). Discusses managerial implications of the findings. For example, one finding was that bonus pack promotions lack credence. Offers suggestions on how to boost the credibility of bonus packs.

Levels in Conceptualizing and Solving Addition and Subtraction Compare Word Problems

This article presents an analysis of conceptual and linguistic complexities of matching situations expressed as word problems and describes possible ways of conceptualizing and solving such problems. Data from first and second graders suggest a progression of four levels in conceptualizing and solving these problems. In the first-Relational-level, children can answer "Who has more/less?" but not "How much more/less?" In the second-Language Cue-level, children are more likely to solve problems with action, Equalizing language ("If he gets 2 more cats, he will have as many cats as dogs") than with static, Compare language ("He has 2 more dogs than cats"). They are especially likely to solve problems in which finding the unknown compared quantity is directed by keywords in the relational sentence. At the third-Understand Matching Situations-level, children find Inconsistent problems (those in which the relational sentence is opposite to the needed solution action) considerably more difficult than other types. Children overwhelmingly solve problems in which one compared quantity is unknown by using an Equalizing approach in which the Extra quantity is added to or taken from the other known quantity. They predominantly solve problems in which the difference between two known compared quantities is unknown by using a Matching conception in which the Small quantity is taken from the Big quantity. At the fourth-Solve Inconsistent-level, children come to be able to solve Inconsistent problems, primarily by using Equalizing conceptions in which the relation given in the relational sentence is reversed.

What is the advantage of private instruction? The example of English vocabulary learning in Greece

The differences between language teaching in private and public institutions in the same country may be usefully illuminated through focussed classroom research. Learners' reports about how they are taught and how they learn new English vocabulary were used as a guide to examine the difference between the two prevailing pedagogical environments in Greece—private institutes of foreign languages and government schools. Contrary to the expectation that the private schools would evidence clearly different and better practices, a complex picture emerged. Some marked weaknesses in the methodology of vocabulary teaching, with a consequent reflection in the way vocabulary is learnt by students, were detected in both. Some ways of overcoming these weaknesses are suggested, and the conclusion is reached that the success of the private institutions is due not so much to the differential quality of their pedagogical contribution as to the extra quantity of instruction that they afford.

Probabilistic Time Scheduling Model for Exponentially Decaying Inventory under Temporary Price Discount

Abstract A probabilistic model for exponentially decaying inventory when supplier announces a temporary price discount for a short time period is considered. Units purchased before or after the period under review will be available at the current price which is higher than the special discount price. In any case it is assumed that the selling price of the units remains fixed. The problem is to determine an extra large quantity to be procured during the lime period in which a special discount is available. This is one time decision problem. Appropriate formulae have been obtained to determine the large quantity to be procured before the price becomes original.

On the mass of the W±-particle from generalized electrodynamics

In this paper, the previously derived analysis from a generalized form of electrodynamics that exhibits some weak- and strong-interaction characteristics at small distances is applied to\(p\bar p\) scattering. It is found that an extra quantity of energy, of order of 342 GeV, is transferred in the collision studied by the CERN group. While this is about four times that of the W± mass, taking account of the approximations used here it is possible to reduce this value toward the observed value, thus remaining in competition with the standard gauge theory of Glashow, Salam and Weinberg.

Locks with Devices to Reduce Salt Intrusion

Navigation locks can strongly influence the water management of an area (both quantity and quality) especially if they belong to a retaining dike separating saltwater from fresh water. Then these locks consume fresh water for the locking process. An extra quantity is also needed for the reduction of salt intrusion. In the past 30 years, various locks with devices to reduce the salt intrusion have been developed especially in The Netherlands. The state of the art of this development is presented. The performance of the various devices will also be described. The major characteristic of the development is a decreasing consumption of fresh water to reduce the salt intrusion combined with an increasing complexity of the devices.

Divergent effects of cholecystokinin, bombesin, and lithium on rat exploratory behaviors

Cholecystokinin induces a reduction in exploratory behaviors which could reflect an underlying behavioral state of either satiety or malaise. To investigate these alternative hypotheses, the effects of CCK were compared to the effects of (a) consumption of an extra quantity of palatable food, of (b) bombesin at doses known to inhibit food consumption, and of (c) lithium chloride, at doses known to produce taste aversion. Parameters of exploration of a novel arena surface and investigation of a novel object placed in the center of the arena were analyzed by an automated video-tracking computer-assisted animal behavior monitor. Cholecystokinin reduced all parameters of exploration. Ingestion of at least one gram of chocolate chip cookie also reduced all exploratory parameters. Bombesin reduced only parameters of approach to the novel object and the center of the arena. Lithium chloride reduced only parameters of approach to the novel object and the center of the arena. CCK may influence exploratory behaviors through mechanisms similar to those produced by ingestion of palatable food, but somewhat different from those produced by lithium and bombesin.

Study of nascent polyethylenes of varied molecular weight by the microcalorimetric method

Using differential scanning microcalorimetry the authors make the first experimental study of the kinetics of melting and non-isothermal crystallization of PE with different MW. The higher enthalpy of melting of the high molecular weight PEs is explained for the first time by the extra quantity of energy required to produce a stressed network of communicating chains. The investigations confirm ideas on the structure of nascent PEs.