1,227 research outputs found
Optimal design of water distribution systems based on entropy and topology
A new multi-objective evolutionary optimization approach for joint topology and pipe size design of water distribution systems is presented. The algorithm proposed considers simultaneously the adequacy of flow and pressure at the demand nodes; the initial construction cost; the network topology; and a measure of hydraulic capacity reliability. The optimization procedure is based on a general measure of hydraulic performance that combines statistical entropy, network connectivity and hydraulic feasibility. The topological properties of the solutions are accounted for and arbitrary assumptions regarding the quality of infeasible solutions are not applied. In other words, both feasible and infeasible solutions participate in the evolutionary processes; solutions survive and reproduce or perish strictly according to their Pareto-optimality. Removing artificial barriers in this way frees the algorithm to evolve optimal solutions quickly. Furthermore, any redundant binary codes that result from crossover or mutation are eliminated gradually in a seamless and generic way that avoids the arbitrary loss of potentially useful genetic material and preserves the quality of the information that is transmitted from one generation to the next. The approach proposed is entirely generic: we have not introduced any additional parameters that require calibration on a case-by-case basis. Detailed and extensive results for two test problems are included that suggest the approach is highly effective. In general, the frontier-optimal solutions achieved include topologies that are fully branched, partially- and fully-looped and, for networks with multiple sources, completely separate sub-networks
Reliability assessment of water distribution systems with statistical entropy and other surrogate measures
There is ever increasing commercial and regulatory pressure to minimise the cost of water distribution networks even as the demand for them keeps on growing. But cost minimizing is only one of the demands placed on network design. Satisfactory networks are required to operate above a minimum level even if they experience failure of components. Reliable hydraulic performance can be achieved if sufficient redundancy is built in the network. This has given rise to various water distribution system optimization methods including genetic algorithms and other evolutionary computing methods. Evolutionary computing approaches frequently assess the suitability of enormous numbers of potential solutions for which the calculation of accurate reliability measures could be computationally prohibitive. Therefore, surrogate reliability measures are frequently used to ease the computational burden. The aim of this paper is to assess the correlation of surrogate reliability measures in relation to more accurate measures. The surrogate measures studied are statistical entropy, network resilience, resilience index and modified resilience index. The networks were simulated with the prototype software PRAAWDS that produces more realistic results for pressure-deficient water distribution systems. Statistical entropy outperformed resilience index in this study. The results also demonstrate there is a strong correlation between entropy and failure tolerance
Biosorption of fluoride ion from water using the seeds of the cabbage tree (Moringa stenopetala)
Conventional water treatment technologies for the removal of fluoride ion may not be feasible for developing countries due to their high investment and operational costs. The aim of this study was therefore, to investigate the fluoride biosorption potential of the seeds of the cabbage tree (Moringa stenopetala). The influence of Moringa dosage, pH, contact time, and initial concentration of fluoride ion was investigated. The maximum fluoride sorption capacity was found to be 1.32 mg.g-1 of dry weight of Moringa seeds at a biomass dosage of 2 g L-1, pH 7.00, initial fluoride ion concentration of 10 mg.L-1 and a contact time of 60 min. The fluoride level was reduced from 10 to 3.4 mg L-1. The adsorption of fluoride ion onto Moringa powder was best described by the pseudo-second-order kinetic model (R2 = 0.99). Theadsorption equilibrium data have been fitted well to Langmuir as well as Freundlich adsorption models (R2≥0.97 for both models). The distribution constant (Kd) and maximum adsorption capacity (Bmax) were significantly influenced by the amount of Moringa and equilibrium fluoride ion concentration (p<0.05). The desorption tests indicated that only 20% of the initially bound fluoride ion was regenerated, while the remaining 80% were bounded with the Moringa powder. This suggests that chemisorption was the possible mechanism of fluoride removal.Key words: Biosorption, chemisorption, desorption, fluoride, isotherm, Moringa stenopetala
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Synthesis of Advanced Hybrid Polymeric Nanomaterials and Characterization of Novel Silsesquioxanes with Desirable Superhydrophobic Coating Properties
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HUBUNGAN PENGETAHUAN PASIEN HIPERTENSI TENTANG OBAT GOLONGAN ACE INHIBITOR DENGAN KEPATUHAN PASIEN DALAM PELAKSANAAN TERAPI HIPERTENSI DI RSUP PROF DR. R. D. KANDOU MANADO
ABSTRACTThe success of treatment of hypertension requires adherence to dietary instructions and therecommended drugs. Education about hypertension and the importance of adherence and sideeffects of drugs administered to the patient is necessary. The purpose of research is todetermine the knowledge of the hypertension patients about ACE inhibitor drug, to knowabout implementation of the adherence of hypertensive patients treated hypertension anddetermine the relationship of knowledge patients about ACE Inhibitors drug with patientsadherence in the implementation of the treatment of hypertension. Sampling sites is in thedepartment of Prof. Dr. R. D. Kandou Manado. Samples were taken that patients do in theclinic internal medicine and use of antihypertensive drugs ACE Inhibitor. Research used aquestionnaire given to the respondents then identified using a chi-square (p<0.05). The resultsshowed that patients with hypertension well knowledge many 48 respondents (96%),hypertensive patients adherence in the implementation of therapy 45 respondents (95%) andthere is a relationship patients knowledge about ACE Inhibitors drugs with patients adherencein the implementation of the treatment of hypertension, with Pearson Chi Square test with p =0.0001 (p <0.05).Key words : Knowledge, Adherence, Hypertension, ACE Inhibitor.ABSTRAKKesuksesan pengobatan hipertensi menuntut kepatuhan terhadap instruksi diet danpenggunaan obat yang dianjurkan. Pendidikan mengenai penyakit hipertensi dan pentingnyakepatuhan serta efek samping obat sangat perlu diberikan kepada pasien. Tujuan penelitianyaitu mengetahui pengetahuan pasien hipertensi tentang obat golongan ACE Inhibitor,mengetahui kepatuhan pasien hipertensi tentang pelaksanaan terapi hipertensi danmengetahui hubungan pengetahuan pasien tentang obat golongan ACE inhibitor dengankepatuhan pasien dalam pelaksanaan terapi hipertensi. Lokasi pengambilan sampel adalah diRSUP Prof. Dr. R. D. Kandou Manado. Sampel diambil yaitu pasien yang melakukanpengobatan di poliklinik interna dan menggunakan obat antihipertensi golongan ACEInhibitor. Penelitian ini menggunakan kuesioner yang diberikan kepada responden kemudiandiidentifikasi menggunakan chi square (p<0,05). Hasil penelitian menunjukkan bahwa pasienhipertensi berpengetahuan baik sebanyak 48 responden (96%), pasien hipertensi patuh dalampelaksanaan terapi sebanyak 45 responden (95%) dan terdapat hubungan antara pengetahuanpasien tentang obat antihipertensi golongan ACE Inhibitor dengan kepatuhan pasien dalampelaksanaan terapi hipertensi, dengan hasil uji Pearson Chi Square didapat nilai p = 0,0001(p<0,05).Kata kunci : Pengetahuan, Kepatuhan, Hipertensi, ACE Inhibitor
Water distribution network optimization using maximum entropy under multiple loading patterns
This paper proposes a maximum entropy-based multi-objective genetic algorithm approach for the design optimization of water distribution networks (WDNs). The novelty is that in contrast to previous research involving statistical entropy the algorithm can handle multiple operating conditions. We used NSGA II and EPANET 2 and wrote a subroutine that calculates the entropy value for any given WDN configuration. The proposed algorithm is demonstrated by designing a six-loop network that is well known from previous entropy studies. We used statistical entropy to include reliability in the design optimization procedure in a computationally efficient way
Differential expression of cold- and diet-specific genes encoding two carp liver delta 9-acyl-CoA desaturase isoforms.
Carp respond to cold by the upregulated expression of Delta9-acyl-CoA desaturase. Here we report the cloning and characterization of Cds2, a second Delta9-acyl CoA-desaturase expressed in carp liver. Both Cds1 and Cds2 complemented the ole1 mutation in Saccharomyces cerevisiae, permitting the synthesis of delta9-monounsaturates, confirming their identity as delta9-desaturases. We demonstrate that under a standard feeding regime it is the Cds2, and not Cds1, transcript that is transiently upregulated during the first few days of cooling from 30 degrees C to 10 degrees C, the period when cold-induced membrane restructuring occurs. Cds2 exists as two differentially spliced transcripts, differing by a small segment from the 3'-untranslated region, the ratio of which varies with temperature. Feeding a diet enriched in saturated fats produced a fourfold increase in Cds1 transcript levels, which was blocked by cooling to 15 degrees C. Cds2 transcript levels, however, showed no substantial response to the saturated diet. Thus carp liver uniquely expresses two isoforms of delta9-acyl CoA desaturase, possibly formed by a recent duplication event, that are differentially regulated by cooling and dietary treatment
KAJIAN YURIDIS TERHADAP TINDAK PIDANA KORUPSI YANG DI LAKUKAN OLEH PEJABAT TNI
Tujuan dilakukannya penelitian ini yaitu untuk mengetahui bagaimana Penerapan Sistem Peradilan Kepada Pejabat TNI Yang Melakukan Tindak Pidana Korupsi dan bagaimana Proses Penuntutan Tindak Pidana Korupsi Yang Dilakukan Pejabat TNI yang dengann metode penelitian hukum normatif disimpulkan bahwa: 1. Penerapan peradilan militer terhadap pejabat TNI yang melakukan tindak pidana korupsi dapat dilakukan penuntutan dan diadili pada peradilan militer atau peradilan umum. 2. Jika perbuatan korupsi oleh pejabat TNI di lakukan Bersama-sama dengan warga sipil maka KPK seharusnya masih berwewenang meski hambatan dimana kewenangannya terbatas. Ini tercantum dalam pasal 42 UU NO 30 tahun 2002 tentang KPKKata kunci: Pejabat TINI; korupsi
Integration of hydraulic and water quality modelling in distribution networks : EPANET-PMX
Simulation models for water distribution networks are used routinely for many purposes. Some examples are planning, design, monitoring and control. However, under conditions of low pressure, the conventional models that employ demand-driven analysis often provide misleading results. On the other hand, almost all the models that employ pressure-driven analysis do not perform dynamic and/or water quality simulations seamlessly. Typically, they exclude key elements such as pumps, control devices and tanks. EPANET-PDX is a pressure-driven extension of the EPANET 2 simulation model that preserved the capabilities of EPANET 2 including water quality modelling. However, it cannot simulate multiple chemical substances at once. The single-species approach to water quality modelling is inefficient and somewhat unrealistic. The reason is that different chemical substances may co-exist in water distribution networks. This article proposes a fully integrated network analysis model (EPANET-PMX) (pressure-dependent multi-species extension) that addresses these weaknesses. The model performs both steady state and dynamic simulations. It is applicable to any network with various combinations of chemical reactions and reaction kinetics. Examples that demonstrate its effectiveness are included
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