Forecasting natural gas consumption in Istanbul using neural networks and multivariate time series methods

Due to copyright restrictions, the access to the full text of this article is only available via subscription.The fast changes and developments in the world's economy have substantially increased energy consumption. Consequently, energy planning has become more critical and important. Forecasting is one of the main tools utilized in energy planning. Recently developed computational techniques such as genetic algorithms have led to easily produced and accurate forecasts. In this paper, a natural gas consumption forecasting methodology is developed and implemented with state-of-the-art techniques. We show that our forecasts are quite close to real consumption values. Accurate forecasting of natural gas consumption is extremely critical as the majority of purchasing agreements made are based on predictions. As a result, if the forecasts are not done correctly, either unused natural gas amounts must be paid or there will be shortages of natural gas in the planning periods

The robust Merton problem of an ambiguity averse investor

We derive a closed form portfolio optimization rule for an investor who is diffident about mean return and volatility estimates, and has a CRRA utility. Confidence is here represented using ellipsoidal uncertainty sets for the drift, given a (compact valued) volatility realization. This specification affords a simple and concise analysis, as the agent becomes observationally equivalent to one with constant, worst case parameters. The result is based on a max–min Hamilton–Jacobi–Bellman–Isaacs PDE, which extends the classical Merton problem and reverts to it for an ambiguity-neutral investor. © 2016, Springer-Verlag Berlin Heidelberg

Diagnosis of endometrial pathologies: transvaginal sonography versus hysteroscopy

Background: Abnormal uterine bleeding (AUB) constitutes 69% of all gynecological complaints in the peri- and postmenopausal age groups. The aim of present study was to compare the accuracy of transvaginal sonography and hysteroscopy in diagnosing intracavitary pathologies in women with abnormal uterine bleeding.Methods: A total of 303 premenopausal women with abnormal uterine bleeding who admitted to the gynecology outpatient clinic of the Istanbul Kanuni Sultan Suleyman Research and Training Hospital, Istanbul, Turkey, between April 2010 and July 2015, and received hysteroscopy, were evaluated retrospectively. The collected data were assembled from the computerised database. All patients underwent pelvic examination, transvaginal ultrasonography, office hysteroscopy and hystopathologic evaluation. Patients with normal appearing uterine cavities on hysteroscopy additionally underwent full curettage. The pathology reports were considered to be the definitive diagnoses of patients. Transvaginal ultrasonography and office hysteroscopy findings were compared with the pathological reports and the sensitivity, specificity, positive and negative predictive values, accuracy values and likelihood ratios of office hysteroscopy and transvaginal ultrasonography were calculated for the detection of endometrial abnormalities.Results: Endometrial polyps were the most commonly identified pathology with a rate of 77.56%. The sensitivity, specificity, positive and negative predictive values of transvaginal sonography for diagnosing endometrial pathologies were 77%, 32%, 75% and 32%, respectively. The same values for hysteroscopy were 93%, 44%, 88% and 48% respectively. Transvaginal sonography had a sensitivity of 20% with a specificity of 4% for submucous myomas. The sensitivity, specificity, positive and negative predictive values of hysteroscopy for submucous myomas when compared to histopathology were 100% for all.Conclusions: The diagnostic accuracy of office hysteroscopy for focal lesions such as polyps or submucous myomas is higher than the accuracy of transvaginal ultrasonography. Due to its high diagnostic accuracy, lower complication rate and the ability to obtain direct biopsy specimens while providing simultaneous treatment, we believe that hysteroscopy will retain its place as the gold standard procedure for the investigation of endometrial pathologies

Nutrient control of eukaryote cell growth: a systems biology study in yeast

<p>Abstract</p> <p>Background</p> <p>To elucidate the biological processes affected by changes in growth rate and nutrient availability, we have performed a comprehensive analysis of the transcriptome, proteome and metabolome responses of chemostat cultures of the yeast, <it>Saccharomyces cerevisiae</it>, growing at a range of growth rates and in four different nutrient-limiting conditions.</p> <p>Results</p> <p>We find significant changes in expression for many genes in each of the four nutrient-limited conditions tested. We also observe several processes that respond differently to changes in growth rate and are specific to each nutrient-limiting condition. These include carbohydrate storage, mitochondrial function, ribosome synthesis, and phosphate transport. Integrating transcriptome data with proteome measurements allows us to identify previously unrecognized examples of post-transcriptional regulation in response to both nutrient and growth-rate signals.</p> <p>Conclusions</p> <p>Our results emphasize the unique properties of carbon metabolism and the carbon substrate, the limitation of which induces significant changes in gene regulation at the transcriptional and post-transcriptional level, as well as altering how many genes respond to growth rate. By comparison, the responses to growth limitation by other nutrients involve a smaller set of genes that participate in specific pathways.</p> <p>See associated commentary <url>http://www.biomedcentral.com/1741-7007/8/62</url></p

Multiagent cooperation for solving global optimization problems: an extendible framework with example cooperation strategies

This paper proposes the use of multiagent cooperation for solving global optimization problems through the introduction of a new multiagent environment, MANGO. The strength of the environment lays in itsflexible structure based on communicating software agents that attempt to solve a problem cooperatively. This structure allows the execution of a wide range of global optimization algorithms described as a set of interacting operations. At one extreme, MANGO welcomes an individual non-cooperating agent, which is basically the traditional way of solving a global optimization problem. At the other extreme, autonomous agents existing in the environment cooperate as they see fit during run time. We explain the development and communication tools provided in the environment as well as examples of agent realizations and cooperation scenarios. We also show how the multiagent structure is more effective than having a single nonlinear optimization algorithm with randomly selected initial points

Robustness of Massively Parallel Sequencing Platforms

The improvements in high throughput sequencing technologies (HTS) made clinical sequencing projects such as ClinSeq and Genomics England feasible. Although there are significant improvements in accuracy and reproducibility of HTS based analyses, the usability of these types of data for diagnostic and prognostic applications necessitates a near perfect data generation. To assess the usability of a widely used HTS platform for accurate and reproducible clinical applications in terms of robustness, we generated whole genome shotgun (WGS) sequence data from the genomes of two human individuals in two different genome sequencing centers. After analyzing the data to characterize SNPs and indels using the same tools (BWA, SAMtools, and GATK), we observed significant number of discrepancies in the call sets. As expected, the most of the disagreements between the call sets were found within genomic regions containing common repeats and segmental duplications, albeit only a small fraction of the discordant variants were within the exons and other functionally relevant regions such as promoters. We conclude that although HTS platforms are sufficiently powerful for providing data for first-pass clinical tests, the variant predictions still need to be confirmed using orthogonal methods before using in clinical applications

Violence against women: The perspective of academic women

<p>Abstract</p> <p>Background</p> <p>Opinion surveys about potential causes of violence against women (VAW) are uncommon. This study explores academic women's opinions about VAW and the ways of reducing violence.</p> <p>Methods</p> <p>Quantitative and qualitative methods were used in this descriptive study. One hundred-and-fifteen academicians participated in the study from two universities. A questionnaire was used regarding the definition and the causes of VAW, the risk groups and opinions about the solutions. Additionally, two authors interviewed 8 academicians from universities other than that of the interviewing author.</p> <p>Results</p> <p>Academicians discussed the problem from the perspective of "gender-based violence" rather than "family violence". The majority of the participants stated that nonworking women of low socioeconomic status are most at risk for VAW. They indicated that psychological violence is more prevalent against educated women, whilst physical violence is more likely to occur against uneducated and nonworking women. Perpetrator related factors were the most frequently stated causes of VAW. Thirty-five percent of the academicians defined themselves as at risk of some act of VAW. Recommendations for actions against violence were empowerment of women, increasing the educational levels in the society, and legal measures.</p> <p>Conclusions</p> <p>Academic women introduced an ecological approach for the explanation of VAW by stressing the importance of taking into account the global context of the occurrence of VAW. Similar studies with various community members -including men- will help to define targeted interventions.</p

Co-creating educational consumer journeys : a sensemaking perspective

To date, customer education has been framed in terms of one-way information provision, at odds with much of the literature on meaning co-creation. Drawing on an ethnography of a specialty coffee purveyor, we show how staff and consumers co-create educational consumer journeys through the deployment of seven practices: auditing, realignment, marrying competing logics, negotiating scripts, evangelizing, expanding collective knowledge, and impression management. These practices require staff and consumers to enact three different educational roles (educator, student, and peer), which are necessary for the co-creation and extension of consumer journeys. The roles, practices and the journeys themselves emerge iteratively through sensebreaking, sensegiving, and sensemaking processes among staff, consumers and the servicescape. Our findings frame customer education as a dynamic process in which meaning is co-created between participants. Furthermore, the cues and touchpoints needed for meaning-making shift as power relations between participants change. Managerially, these findings highlight the potential of co-created educational consumer journeys to expand established market categories

Higher Dimensional Cylindrical or Kasner Type Electrovacuum Solutions

We consider a D dimensional Kasner type diagonal spacetime where metric functions depend only on a single coordinate and electromagnetic field shares the symmetries of spacetime. These solutions can describe static cylindrical or cosmological Einstein-Maxwell vacuum spacetimes. We mainly focus on electrovacuum solutions and four different types of solutions are obtained in which one of them has no four dimensional counterpart. We also consider the properties of the general solution corresponding to the exterior field of a charged line mass and discuss its several properties. Although it resembles the same form with four dimensional one, there is a difference on the range of the solutions for fixed signs of the parameters. General magnetic field vacuum solution are also briefly discussed, which reduces to Bonnor-Melvin magnetic universe for a special choice of the parameters. The Kasner forms of the general solution are also presented for the cylindrical or cosmological cases.Comment: 16 pages, Revtex. Text and references are extended, Published versio