Some numerical methods for solving stochastic impulse control in natural gas storage facilities

The valuation of gas storage facilities is characterized as a stochastic impulse control problem with finite horizon resulting in Hamilton-Jacobi-Bellman (HJB) equations for the value function. In this context the two catagories of solving schemes for optimal switching are discussed in a stochastic control framework. We reviewed some numerical methods which include approaches related to partial differential equations (PDEs), Markov chain approximation, nonparametric regression, quantization method and some practitioners’ methods. This paper considers optimal switching problem arising in valuation of gas storage contracts for leasing the storage facilities, and investigates the recent developments as well as their advantages and disadvantages of each scheme based on dynamic programming principle (DPP

Usahawan industri dan sederhana (IKS) pelancongan: Menangani isu-isu perundangan terkini

lndustri pelancongan memainkan peranan penting dalam menjana pertumbuhan ekonomi negara. Dalam usaha mempertingkatkan dun memajukan industri ini, penglibatan industri kecil dun sederhana (IKS) tetap memainkan peranannya sendiri. Pengetahuan asas dari sudut perundangan amat perlu kepada usahawan-usahawan IKS pelancongan bermula dari proses memulakan pemiagaan sehinggalah kepada ianya dijalankan. Oleh yang demikian, artikel ini akan membincangkan proses penubuhan sesebuah perniagaan, pemilihan bentuk-bentuk pemiagaan yang sesuai dan undang-undang yang berkaitan dalam menjalankan urusan pemiagaan seharian

Optimised transmission tower earthing: experience in design and operation

A large percentage of transmission line outages in Malaysia are due to lightning activity with backflashover being the main cause. Previous investigations have indicated that tower footing earth resistance is one of the main factors in reducing the occurrence of backflashovers. The present studies review some of the tower earthing design options. From this standard designs are proposed together with a practical method of optimising the design based on soil resistivity measurement data. The process is presented via a flowchart which includes the main measurement and design steps. This allows different standard designs to be selected to suit the type of soil structure at the site of the proposed transmission tower. Where measurements indicate a high resistivity layer with underlying low resistivity soil, an electrode design relying more on driven rods is used. Conversely, a design using more horizontal electrode would be selected where the soil structure is of low resistivity above high. Some practical methods are also described which can be included in the design to improve the ease with which maintenance testing can be carried out. The results of trial installations on selected towers have been performed and the results are discussed

Optical and electrical characteristics of (LiCl)x(P2O5)1-x glass.

Homogeneous (LiCl) x (P2O5)1 − x glasses were synthesised using a melt-quenching method for x = 0.1–0.6 in the interval of 0.05. The amorphous structure of the samples was evident by the X-ray diffraction spectrum. The short range structures of the binary phosphate samples were examined by Fourier transform infrared spectroscopy, whilst the density of the samples was measured as supportive data for the investigations. The results of refractive indices as measured using an ellipsometer reveal the homogeneity of samples and was found to depend on the glass composition. The electrical properties of the glasses were investigated by ac impedance spectroscopy from 10 mHz to 1 MHz for temperatures ranging from room temperature to 573 K. An estimation of the bulk resistivity was obtained by taking the intercepts on the real axis at low frequencies of the complex impedance plot. The dc conductivities derived from the reciprocal of resistivity values were found to obey the Arrhenius relationship, and its activation energy shows a decreasing trend with the increase in LiCl content in the glass. Lastly, an equivalent circuits consisting of real and complex capacitors is proposed to describe the dielectric response of the glass

The use of reflection mode ultrasonic transceiver sensor in pipeline inspection guage to monitor pipeline internal corrosion

Aging gas transmission pipelines are prone to internal corrosion due to the presence of carbon dioxide and hydrogen sulphide in the natural gas constituents. Commonly, the in-line inspection tool known as Pipeline Inspection Gauge (PIG) is applied to perform the corrosion inspection of the pipeline. This paper describes an ultrasonic instrumentation system for PIG to monitor internal corrosion of pipeline. The system consists of ultrasonic transceiver sensor, ultrasonic driving circuitry and data acquisition system. The hardware is equipped with a sensor carrier which is propelled along the test pipeline. The time of flight (TOF) of the ultrasonic wave is measured and was used to evaluate the internal corrosion of pipeline. An initial experimental instrument was set up to perform the distance measurement test at a frequency of 390 kHz, to simulate the changes of pipe wall thickness due to corrosion effect. Surface anomalies were created at different positions to simulate the changes of pipe wall thickness due to the corrosion effect. Variation in measured distances implied the existence of the surface anomalies. The results of the simulated surface anomalies showed that the percentage error was less than + 5%. The large value of average DC voltage gave indication of distance increment due to the depth of the surface anomalies. The developed ultrasonic instrumentation system is capable to monitor the internal corrosion of pipeline

DO CURRENT AWARENESS AND EDUCATIONAL PROGRAM TOWARDS UNREGISTERED DRUGS EFFECTIVE FOR PUBLIC? PHARMACISTS' PERCEPTIVE

Objective: Awareness and educational programme are one of the solutions to reduce unregistered drugs usage. In Malaysia, an agency called Pharmaceutical Services Division (PSD) and Pharmacy Enforcement Division (PED) are highly active in yielding many awareness programmes throughout the country as well as in its website. The goal of this research was to explore the pharmacist views or perceptions on the current awareness and educational programme on registered drugs.Methods: These findings emerged from one-on-one semi-structured interview guided with sixteen pharmacists in Klang Valley who have represented the voice from the pharmacists throughout Malaysia.Results: Six themes identified: ‘Consumer utility', ‘low health literacy', ‘social and education influenced', ‘equitable access to information', ‘promotion' and ‘persistent'. These themes emphasise the current awareness to improve and provide the programme to everyone in Malaysia to get the same information regardless they're staying. Pharmacists also expressed their concern about the current consumer who only cares about their benefit such as fast effect; cheap and easy to get by ignoring the bad impact if they consume the unregistered products. The pharmacists also believed that the health literacy, the social and educational level also influenced the purchase behaviour amongst consumer.Conclusion: The findings indicate that the management of unregistered drugs needs to involve every organisation. Future research could develop a particular measure and score on awareness and knowledge amongst public on this issue. This test can be used as the indicator to evaluate the outcome of the future knowledge programmed.Keywords: Unregistered drugs, Awareness and educational programme, Pharmacist, Public, Perspective

Synthesis and optical properties of ZnO-TeO2 glass system

Problem statement: Systematic series of ZnO-TeO2 glasses with mole fraction of 0.10-0.40 ZnO content with an interval of 0.05 were studied to obtain their physical and optical properties. Approach: All the glass samples were synthesized by rapid melting quenching method under controlled conditions, while their refractive indices (n) were measured by the EL X-02C high precision ellipsometer. The room temperature absorption of all glass samples were determined using Camspec M350 double beam UV-visible spectrophotometer. The infrared (IR) spectra of each glass samples were recorded with Thermo Nicolet Fourier Transform-Infrared (FT-IR) spectrophotometer. Their physical properties were measured and the amorphous nature was confirmed by the x-ray diffraction technique. Results: The increase of refractive index of the TeO2-ZnO glasses with the addition of ZnO was best explained in terms of either electron density or polarizability of the ions. The absorption edge shift to higher energy (shorter wavelength) with increasing ZnO content was observed in this glass. The optical band gap (Eopt) of zinc tellurite glass decreases with increasing of ZnO content probably due to the increment of Non-Bridging Oxygen (NBO) ion contents which eventually shifted the band edge to lower energies. Conclusion/Recommendation: The physical and optical properties of zinc tellurite glasses were found generally affected by the changes in the glass composition. FTIR spectra of zinc tellurite glass revealed broad, weak and strong absorption bands in the investigated range of wave numbers from 4000-400 cm-1 which associated with their corresponding bond modes of vibration and the glass structure. The addition of ZnO into TeO2 glass network shifted the major band from 626 cm-1 (for pure TeO2 glass) to the band at around 669 cm-1

Effects of MgO on dielectric properties and electrical conductivity of ternary zinc magnesium phosphate glasses.

Glasses with composition (ZnO)30(MgO)x(P2O5)70-x(ZnO)30(MgO)x(P2O5)70-x (x = 5, 8, 13, 18 and 20 mol%) have been successfully prepared by the melt-quenching technique. The dielectric permittivity (ε′ε′) and loss factor (ε″ε″) were measured in the frequency range of 0.01 Hz to 1 MHz and in the temperature range of 303 to 573 K. From the results, there is evidence of dipolar relaxation occurring between View the MathML source103–106Hz, while at low frequencies, the spectrum is dominated by dc conduction which was manifested by the 1/ω1/ω slope of the loss factor plot. The value of the relaxing frequency (ωpωp) plotted against 1/T1/T shows a single relaxation mechanism with an activation energy of 0.45 eV. The average value of the activation energy for dc conduction was much higher (1.25 eV) suggesting its diffusion movement had encountered more difficult steps than the small displacement changing dipoles. With increasing MgO concentration, the dielectric permittivity (ε′ε′), dc conductivity (σdcσdc) and dielectric strength (ΔεΔε) decrease and these were attributed to some of the magnesium ions participated in the glass-forming positions as well as modifiers. At lower temperatures, the complex permittivity plots present a skewed arc with center point lying below the real axis which is a non-Debye characteristic. The empirical data were sufficiently fitted by using the Harviliak–Negami equation. The temperature dependent of the parameter αα is discussed

A Study On The Perfomance Of Sedimentation Tank At The Sungai Kampar Water Treatmeny Plant.

This paper discusses the performance of soIid-liquid separation pfocess at the Sg Kampar Water Treatment works

Reduction of POME final discharge residual using activated bioadsorbent from oil palm kernel shell

A double insulated carbonisation-activation reactor was developed in order to produce activated carbon with high yield and surface area. This reactor was double insulated using low cement castable and covered around the internal space of the reactor with stainless steel plated and fibre glass jacketed heat insulation layer, which allow efficient heat transfer into the bed of material in the reactor. The carbonisation of oil palm kernel shell (OPKS) at 400 °C, followed by steam activation at 500–1000 °C continuously in the same reactor, with steam flow rate of 12.80–18.17 L/min had improved the activated carbon surface area from 305 ± 10.2 m2/g to 935 ± 36.7 m2/g and gave a high yield of 30% within 7 h retention time with a low gaseous emission. The activated carbon produced was successfully applied as bioadsorbent for the treatment of POME final discharge with the reduction of TSS, COD, colour and BOD up to 90%, 68%, 97% and 83%, respectively which met the standard set by Department of Environment Malaysia (DOE)