Store capacity optimisation

The problem is one of increasing the efficiency of distributing paper rolls from the manufacturing plants to the customers. A related problem is one of utilising the available capacity at the customer stores in an effective manner. During the MISG, several approaches to the above problems were proposed. In this report we describe the problem and several methods for solving it. Preliminary results are provided for some of these

Gas field scheduling

Woodside Offshore Petroleum is the operator in the development of new gas fields in Australia's North West Shelf project. Sequencing the development of new gas fields in this project is a key determinant of its return on investment. This development sequence has constraints imposed by infrastructure and contractual obligations as well as natural features. The determination of an optimal or very good solution may involve a number of techniques from operations research. The study group attempted several approaches to the problem, principal amongst them being mathematical programming and dynamic programming. A few other heuristic approaches were also considered. The mathematical programming approach was able to yield solutions to small instances of the problem. The group was able to identify several avenues for further research and work on the problem is ongoing

On sign changes for almost prime coefficients of half-integral weight modular forms

For a half-integral weight modular form $f = \sum_{n=1}^{\infty} a_f(n)n^{\frac{k-1}{2}} q^n$ of weight $k = l +\frac{1}{2}$ on $\Gamma_0(4)$ such that $a_f(n)$ ($n$ $\in$ $\mathbb{N}$) are real, we prove for a fixed suitable natural number $r$ that $a_f(n)$ changes sign infinitely often as $n$ varies over numbers having at most $r$ prime factors, assuming the analog of the Ramanujan conjecture for half-integral weight forms.Comment: To appear in Mathematik

Pursuit on a Graph Using Partial Information

The optimal control of a "blind" pursuer searching for an evader moving on a road network and heading at a known speed toward a set of goal vertices is considered. To aid the "blind" pursuer, certain roads in the network have been instrumented with Unattended Ground Sensors (UGSs) that detect the evader's passage. When the pursuer arrives at an instrumented node, the UGS therein informs the pursuer if and when the evader visited the node. The pursuer's motion is not restricted to the road network. In addition, the pursuer can choose to wait/loiter for an arbitrary time at any UGS location/node. At time 0, the evader passes by an entry node on his way towards one of the exit nodes. The pursuer also arrives at this entry node after some delay and is thus informed about the presence of the intruder/evader in the network, whereupon the chase is on - the pursuer is tasked with capturing the evader. Because the pursuer is "blind", capture entails the pursuer and evader being collocated at an UGS location. If this happens, the UGS is triggered and this information is instantaneously relayed to the pursuer, thereby enabling capture. On the other hand, if the evader reaches one of the exit nodes without being captured, he is deemed to have escaped. We provide an algorithm that computes the maximum initial delay at the entry node for which capture is guaranteed. The algorithm also returns the corresponding optimal pursuit policy

Evaluation of Australian Ladybird Beetle Cryptolaemus montrouzieri Mulsant against Green Shield Scale Chloropulvinaria psidii (Maskell) on some Medicinal Plants

Severe infestation of green shield scale Chloropulvinaria psidii (Green) was observed during 2003-04 on the medicinal plants namely Withania somnifera, Madhuca longifolia, Mimusops elengi and Wrightia tinctoria. The Australian ladybird beetle Cryptolaemus montrouzieri Mulsant was released @ 20 larvae/plant. Following the release of C. montrouzieri , the scale population declined from 173.48 to 4.35/plant on W. somnifera, 30.49 to 1.20/plant on M. longifolia, 90.20 to 3.57/plant on M. elengi and 240.86 to 4.92/plant on W. tinctoria. There was 89.13 to 97.96% reduction in scale population 45-75 days after release of C. montrouzieri on the above medicinal plants. No other natural enemy, except C. montrouzieri, was recorded on C. psidii. There was no correlation between temperature, relative humidity or rainfall and scale population. Hence, the reduction in population of green shield scale was attributed mainly to the action of C. montrouzieri

Colonization of Introduced Parasitoid, Encarsia guadeloupae Viggiani, on the Exotic Spiralling Whitefly, Aleurodicus dispersus Russell, Infesting Ornamentals

The exotic spiralling whitefly, Aleurodicus dispersus Russell, was observed to infest several ornamentals including rose, hibiscus, poinsettia and acalypha in and around Bangalore. Efforts were made to colonize the aphelinid parasitoid, Encarsia guadeloupae Viggiani, during 2002 - 2003 on the above ornamentals infested with the spiralling whitefly. A total of five predators, namely, Axinoscymnus puttarudriahi Kapur and Munshi, Cryptolaemus montrouzieri Muls., Anegleis cardoni (Weise), Mallada astur (Banks) and Cybocephalus sp. were observed on the spiralling whitefly on these ornamentals during the study but their impact on the spiralling whitefly was negligible. Inoculative releases of E. guadeloupae were made on rose (156 adults), hibiscus (179 adults), poinsettia (124 adults) and acalypha (247 adults). Encarsia guadeloupae was recovered within a month after its release with 3.43-32.94% parasitism. A steady decline in the population of spiralling whitefly was observed on these ornamentals. Encarsia guadeloupae was found to be the only parasitoid encountered throughout the study and the total parasitism steadily increased up to 96.00% on rose, 86.40% on hibiscus, 90.40% on poinsettia and 39.86% on acalypha at six months from release. Parasitism by E. guadeloupae was significant and negatively correlated with the population of spiralling whitefly on all the four ornamentals

Who shares and who doesn't? Results of the UK Sharing Economy Consumer Survey 2017

The survey, which was conducted in July 2017, captures 1220 responses, and is based on a representative sample of UK population based on gender, income level, education level, and place of residence in the UK. It was structured to ask questions about informants’ current usage of, opinions about, and future intentions to use the following sharing categories: places to stay (e.g. Airbnb, Beds on Board), rides (e.g. Uber, Liftshare), rental cars (e.g. Easycar, Zipcar), parking (e.g. JustPark, Your Parking Space), services (e.g. Parcelly, TaskRabbit), meals (e.g. MealSharing, Eatwith), pre-owned goods (e.g. eBay, Gumtree) and funding (e.g. Justgiving, Crowdcube)