A hybrid GA–PS–SQP method to solve power system valve-point economic dispatch problems

This study presents a new approach based on a hybrid algorithm consisting of Genetic Algorithm (GA), Pattern Search (PS) and Sequential Quadratic Programming (SQP) techniques to solve the well-known power system Economic dispatch problem (ED). GA is the main optimizer of the algorithm, whereas PS and SQP are used to fine tune the results of GA to increase confidence in the solution. For illustrative purposes, the algorithm has been applied to various test systems to assess its effectiveness. Furthermore, convergence characteristics and robustness of the proposed method have been explored through comparison with results reported in literature. The outcome is very encouraging and suggests that the hybrid GA–PS–SQP algorithm is very efficient in solving power system economic dispatch problem

Turbo-Detected Unequal Error Protection Irregular Convolutional Codes Designed for the Wideband Advanced Multirate Speech Codec

Abstract—since the different bits of multimedia information, such as speech and video, have different error sensitivity, efficient unequalprotection channel coding schemes have to be used to ensure that the perceptually more important bits benefit from more powerful protection. Furthermore, in the context of turbo detection the channel codes should also match the characteristics of the channel for the sake of attaining a good convergence performance. In this paper, we address this design dilemma by using irregular convolutional codes (IRCCs) which constitute a family of different-rate subcodes. we benefit from the high design flexibility of IRCCs and hence excellent convergence properties are maintained while having unequal error protection capabilities matched to the requirements of the source. An EXIT chart based design procedure is proposed and used in the context of protecting the different-sensitivity speech bits of the wideband AMR speech codec. As a benefit, the unequalprotection system using IRCCs exhibits an SNR advantage of about 0.4dB over the equal-protection system employing regular convolutional codes, when communicating over a Gaussian channel

Foolproof quick-release locking pin

Locking pin can be withdrawn only when stress on the joint is negligible. Pin consists of a forward-pointing sleeve, a spring-loaded sliding handle, and a sliding plunger. Plunger movement controls installation and withdrawal of pin

Strategi Diferensiasi Produk dalam Menghadapi Persaingan Kuliner (Kasus Bisnis Sop Tunjang Tampan di Pekanbaru)

This study was conducted at the First Tunjang Sop located on Jl . Cinnamon Pekanbaru Riau , which is a company engaged in the trade . The purpose of this study was to determine the strategy of product differentiation in the face of the culinary competition in business tunjang perjama pekanbaru soup . The research methods include the location of the research conducted on the first attempt tunjang pekanbaru soup , types and sources of data used is primary data , where the data is obtained directly from the company include product differentiation strategy that made the first attempt tunjang pekanbaru culinary soup and secondary data is data annual obtained from the companys other sales data from the years 2008-2012 , and a general overview of the company , while the analysis of the data using the method of analyzing the data in this study would be conducted degan qualitative descriptive method .Based on the results of research on product differentiation strategy in the face of the culinary competition in the business case tunjang Handsome soup can be seen that most of the respondents to respond well enough that as many as 21 people , or 52.50 % , then the respondents who gave a good response ditangggapi many as 8 or 20 , 00 % and to respond less well addressed as many as 11 people or 27.50 %The obstacles in the face of the product differentiation strategy culinary competition among others : That the lack of parking, lack of ability of the company to maintain a corporate image , a lack of desire and willingness to further develop its business enterpriseFrom these results , the actual product being supported first Handsome culinary soup is considered to be able to compete , but business owners should still consider the quality of marketed products , as well as looking for new innovations . This is done so that businesses can compete soup first SOP tunjang To nex time .Key word : Product, differentiation, marketing strategy,business competitio

Comparing the Determinants of Fund Flows in Domestically Managed Malaysian Islamic and Conventional Equity Funds

Purpose: This paper aims to provide an empirical evidence on the fund flows-past return performance relationship by also considering the management expense ratio, the portfolio turnover, the fund size and the fund age of Islamic equity funds (IEF) investors in comparison with conventional equity funds (CEF) investors. Design/methodology/approach: By using panel data, the sample of Malaysian domestic managed equity funds are considered comprised of 20 individual funds from IEF and CEF respectively from 2011 to 2013. Findings: The results provide evidence that IEF investors have different factors when choosing funds in comparison with CEF investors. The study finds that the key factor influencing the fund flows of IEF is the management expense ratio, compared to the CEF which is fund size. This study also shows that all the fund characteristics of IEF and CEF are positively or negatively related to the fund flows. Research limitations/implications: The present study may be extended by considering other fund categories such as the money market fund, the balanced fund, the bond fund and the fixed income fund. Practical implication: The empirical findings of this paper clearly call for fund managers and investors to review their investment policy. The results could also provide better information and guidance for investors as well policy-makers on the factors that affect the fund flow for Malaysian Islamic and conventional equity funds. Originality/value: This paper is among the earliest empirical evidence studies on the fund flows-past return performance relationship by focusing in a comparative manner on IEF investors and CEF investors in Malaysia

Water vapour effects of cyclic oxidation on Fe-Cr alloys

Fe-Cr alloys (Cr: 9-30 wt%) were subjected to cyclic oxidation in Ar-20%O2, Ar-20%O2-5%H2O and Ar-10%H2-5%H2O (partial pressure of oxygen, pO2 = 1.1 ¥ 10-16atm). Oxidation weight change measurement showed that in general, increasing Cr content reduced the oxidation rate. At Cr 25%, the weight gain became very low due to formation of Cr2O3 layer. Adding 5%H2O to Ar-20%O2 accelerated the oxidation rate of alloys with Cr < 20%. However, this accelerating effect did not appear in high chromium content alloys. XRD analysis showed that for alloys with Cr < 20%, wustite and spinel were formed at low pO2, while at high pO2, hematite, iron oxide and spinel were formed. For high Cr content alloy only Cr2O3 was detected. Cross-section analysis showed that the spinel was formed by internal oxidation. The thickness and size of this internal oxide zone increased with increasing Cr content. A dense chromia layer was observed when the Cr content was above 25%. The oxides scales formed in water vapour were more porous and less compact than the scale formed in dry oxygen. The accelerating effect of water vapour on Fe-Cr oxidation is discussed in terms of gas-solid interactions

The effects of height and frequency of previous defoliation on nodulation, nitrogen fixation and regrowth of phasey bean

Inoculated seeds of phasey bean (Macroptilium lathyroides cv. Murray) were sown in a sand culture in a naturally-lit glasshouse, and imgated daily with nitrogen-Free nutrient solution. At early flowering, the plants were either left uncut or cut at node 5 (high) or node 1 (low), retaining the corresponding residual leaf areas of 74, 11 and Ocm 2 plant 1respectively. Following this initial cutting, new shoots were individually harvested at the frequency of one, two, three, four or eight times over a penriod of 56 days in Phase 1. Total dry weight of new shoots, seed yields and nitrogen concentrations in the herbage were assessed. A II plants were allowed to regrow during the next 21-day recovery period in Phase 2. Then, the root systems and plant tops were harvested. Nodulation,nitrogen fixation (total N) and regression analyses on s011Je plant parameters were computed. In Phase 1, cumulative yields of new shoots harvested following high or low-level cutting declined significantly with increasing harvesting frequency, but yield reductions due to low-level cutting were detected only under high harvesting frequencies. In Phase 2, recovery growth was always better following high than low-level cutting, but unexpectedly, the various harvesting frequencies had no effect on recovery growth following high cutting. After low-level cutting, high or low harvesting frequency reduced recovery growth compared with moderately frequent defoliation (two harvests in 56 days), which coincided with early flowering on the new top growth. Recovery growth had a positive linear correlation (r = 0.98 ***) with nitrogen fixation, which was also linearly correlated with nodulation. These results are briefly discussed with reference to the current concept that regrowth of nodulated forage legumes is largely dependent on symbiotic nitrogen fixation

Variable Selection Using aModified Gibbs Sampler Algorithm with Application on Rock Strength Dataset

اختيار المتغيرات مهمة ضرورية ومطلوبة في مجال النمذجة الإحصائية. حاولت العديد من الدراسات تطوير وتوحيد طرق اختيار المتغيرات، ولكن من الصعب القيام بذلك. السؤال الأول الذي يحتاج الباحث أن يسأل نفسه عنه هو ما هو أهم المتغيرات التي يجب استخدامها لوصف الاستجابة لمجموعة بيانات معينة. في هذا العمل، تمت مناقشة طريقة جديدة في الاستدلال بايزي لأختيار المتغيرات باستخدام تقنيات عينات Gibbs. بعد تحديد النموذج، تم اشتقاق التوزيعات الخلفية لجميع المعلمات. تم اختبار طريقة الاختيار للمتغير الجديد باستخدام 4 مجاميع من البيانات. تمت مقارنة الطريقة الجديدة مع بعض الطرق المعروفة التي هي قليل مربعات الخطأ (OLS)، عامل انكماش مطلق واختيار (Lasso)، وتسوية تيكونوف (Ridge). أظهرت دراسات المحاكاة أن أداء طريقتنا أفضل من الأخرى حسب الخطأ ووقت الاستهلاك. تم تطبيق الطرق على مجموعة بيانات Rock Strength، وكانت الطريقة الجديدة التي تم تقديمها أكثر كفاءة ودقة.Variable selection is an essential and necessary task in the statistical modeling field. Several studies have triedto develop and standardize the process of variable selection, but it isdifficultto do so. The first question a researcher needs to ask himself/herself what are the most significant variables that should be used to describe a given dataset’s response. In thispaper, a new method for variable selection using Gibbs sampler techniqueshas beendeveloped.First, the model is defined, and the posterior distributions for all the parameters are derived.The new variable selection methodis tested usingfour simulation datasets. The new approachiscompared with some existingtechniques: Ordinary Least Squared (OLS), Least Absolute Shrinkage and Selection Operator (Lasso), and Tikhonov Regularization (Ridge). The simulation studiesshow that the performance of our method is better than the othersaccording to the error and the time complexity. Thesemethodsare applied to a real dataset, which is called Rock StrengthDataset.The new approach implemented using the Gibbs sampler is more powerful and effective than other approaches.All the statistical computations conducted for this paper are done using R version 4.0.3 on a single processor computer

Community acquired pneumonia incidence before and after proton pump inhibitor prescription: population based study

Objective To examine the risk of community acquired pneumonia before and after prescription of proton pump inhibitor (PPI) and assess whether unmeasured confounding explains this association. Design Cohort study and self controlled case series. Setting Clinical Practice Research Datalink (1990 to 2013) in UK. Participants Adult patients with a new prescription for a PPI individually matched with controls. Main outcome measures Association of community acquired pneumonia with PPI prescription estimated by three methods: a multivariable Cox model comparing risk in PPI exposed patients with controls, corrected for potential confounders; a self controlled case series; and a prior event rate ratio (PERR) analysis over the 12 month periods before and after the first PPI prescription. Results 160 000 new PPI users were examined. The adjusted Cox regression showed a risk of community acquired pneumonia 1.67 (95% confidence interval 1.55 to 1.79) times higher for patients exposed to PPI than for controls. In the self controlled case series, among 48 451 PPI exposed patients with a record of community acquired pneumonia, the incidence rate ratio was 1.19 (95% confidence interval 1.14 to 1.25) in the 30 days after PPI prescription but was higher in the 30 days before a PPI prescription (1.92, 1.84 to 2.00). The Cox regressions for prior event rate ratio similarly showed a greater increase in community acquired pneumonia in the year before than the year after PPI prescription, such that the analysis showed a reduced relative risk of pneumonia associated with PPI use (prior event rate ratio 0.91, 95% confidence interval 0.83 to 0.99). Conclusion The association between the use of PPIs and risk of community acquired pneumonia is likely to be due entirely to confounding factors