cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2015.242
title: Assembly line set up for rear lamp cable set

description: The objective of this research is to establish an assembly line for rear lamp cable set by improving the prototype assembly line since it is unable to meet the forecasted demand producing 2104 cables per day as compared to the target of 2424 cables per day. Work Study, divided into two parts (method study and work measurements), and Assembly Line Balancing techniques are applied. This research consists of five phases including define, method study, assembly line balancing, work measurement, and conclusion. In define phase, materials and products, procedures and work elements, problems, objectives and measurements, and project team are identified. In method study, micro-motions of the process are studied in order to generate more efficient method. The result of this phase is a standardised method for assembling. In assembly line balancing, standardised work elements are assigned to workstations by using Largest Candidate Rule and Rank Positional Weight; the results from two methods are examined. Once workstations are defined, in work measurement, workstations’ times and rest-pause regime are determined. Under time study, performance rating will evaluate the worker’s pace relative to standard performance to determine the standard time. Furthermore, rest-pause regime will be determined by International Labour Organisation’s method and Williams’s method. The results from two methods will be examined for suitability in assembly line rest-pause regime. From all phases, every workstation time is below the takt time, 16.35 seconds; the assembly line can now produce 2442 cables per day as compared to old productivity at 1912 cables, 27% increase in productivity. Moreover, assembly line is more balanced due to 70% reduction of smoothness index from 13.39 to 3.91.
DOI: 10.14457/cu.the.2015.243
title: DEVELOPMENT ON FAST NEUTRON RADIOGRAPHY SYSTEM BY USING PORTABLE NEUTRON GENERATOR

description: Most of the concealed explosives and hazardous materials share the similar physical characteristics with the benign materials and are consisted of almost exclusively the elements H, C, N, and O. In comparison to the conventional X-ray inspection system, the neutron radiography is more sensitive with the light elements and, therefore, is more suitable for detecting the materials composed of such elements. Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on a portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a neutron shielding material sandwiched between two identical imaging plates is used as a screen behind the exposed material. An acrylic plate was used as the neutron shielding material as it can attenuate the fast neutrons but remains essentially transparent to the X-ray. A binary XOR operation is then applied on the images obtained by the two imaging plates in order to extract the information regarding the neutron exposure. The raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons. The results also confirm that the fast neutron radiography of the concealed materials composed of H, C, N and O is possible. This can then be useful for detecting the concealed explosive materials composed of such elements.
DOI: 10.14457/cu.the.2015.244
title: Formation of subcritical thickness InAs nanostructures on InGaAs cross-hatch patterns by in situ annealing

description: This thesis presents the formation of subcritical thickness InAs nanostructures on In0.2Ga0.8­As cross-hatch patterns (CHPs) with GaAs (001) substrate by in situ annealing in molecular beam epitaxy (MBE). The subcritical formation of InAs is characterized by atomic force microscopy (AFM) for surface morphology and topology. The real time observation showed no sign of quantum dots (QDs) formation during the subcritical thickness. Subcritical thickness InAs nanostructures on In0.2Ga0.8As CHPs show interesting nanostructures which formed into atomic wires along [1-10] direction. If varies the thickness of InAs layer from 1.4, 1.5, and 1.6 monolayer (ML), the distance between atomic wires become closer to each other, resulting in higher density of wires. However, the height of the wires is considered to be the same at 0.3 nm, which is equivalent to 1 ML of InAs layer. Moreover, the CHPs also affect the formation of subcritical thickness InAs on both [110] and [1-10] directions as well. The results indicate that subcritical thickness InAs tends to elongate along [1-10] direction, and confined on the [110] direction. For the photoluminescence (PL) spectrum displays the highest PL peak at 1.45 eV, corresponding to the InAs wetting layer indicating a high structural quality which may be suitable for optical applications.
DOI: 10.14457/cu.the.2015.245
title: ADSORPTION OF HEAVY METALS IN SEAWATER USING AMIDOXIME ADSORBENT PREPARED BY GAMMA IRRADIATION TECHNIQUE

description: For safety and safeguards purposes, amidoxime fibers were investigated for the ability to adsorb heavy metals from seawater. Amidoxime fibers were successfully synthesized by the simultaneous irradiation grafting technique at low temperature using Co-60 as the gamma ray source. The degree of cografting of AN/MAA onto LDPE fibers at the total dose of 40 kGy was calculated to be approximately 52%. The fibers exhibit the ability to adsorb Pb, As, Hg and uranium form seawater. Under the studied conditions, for the case of Pb, the adsorption capability was 5.33 – 33.50 g-Pb/kg-adsorbent. For the case of As, the adsorption capability was approximately 0.25 – 0.77 g-As/kg-adsorbent. For the case of Hg, the adsorption capability was approximately 0.0001 – 0.0075 g-Hg/kg-adsorbent. For the case of U, the adsorption capability was approximately 0.0005 – 0.0057 g-U/kg-adsorbent.The adsorption also reduced with submerging time. Thus, the amidoxime fibers can be used as a very effective detector for Pb, As, Hg and uranium in seawater for the submerging time as short as 3 days.
DOI: 10.14457/cu.the.2015.246
title: INFLUENCE OF GEOMETRY, CRACK-FACE CONDITIONS AND LOADING ON INTENSITY FACTORS OF CRACKS IN 3D LINEAR PIEZOELECTRIC MEDIA

description: This thesis presents extensive results to demonstrate the influence of the crack geometry, crack-face boundary conditions, remote loading conditions and permittivity of a medium inside the crack gap on the intensity factors of cracks in linear piezoelectric media. A spherical cap crack, a cylindrical crack, a tunnel crack and a pair of identical penny-shaped cracks are chosen as representative cracks in the present study to fully explore the role of all parameters. In simulations, the weakly singular SGBEM is used to determine the unknown crack-face data and special local interpolations are employed along with the explicit formula to enhance the near-front approximation and directly extract intensity factors along the crack front. Results from a numerical study indicate that the curvature, the crack subtended angle and the crack aspect ratio significantly influence the value of the intensity factors. It is also observed that KI of impermeable, permeable and semi-permeable non-planar cracks exhibit completely different behavior from that of planar cracks when the mechanical load increases. Moreover, KI for both impermeable and semi-permeable non-planar cracks depends strongly on the applied electric field. These findings are in contrast with results in the case of planar cracks where KI of impermeable, permeable and semi-permeable cracks are identical and independent of the electric field. In addition, as the permittivity inside the crack gap increases, the stress intensity factors of impermeable, permeable and semi-permeable non-planar cracks are not identical and the semi-permeable solution strongly depends on the permittivity of a medium inside the crack gap.
DOI: 10.14457/cu.the.2015.247
title: Improvement of surveillance video coding based on IEEE 1857 standard

description: IEEE 1857 Video Coding standard is introduced with the aims to double compression rate for high efficiently and low complexity for video surveillances. However, to compress with high compression ratio is affected to recognition. In this research, we propose a new algorithm to improve SIFT similarity by using feature map, which is detected keypoint features from SIFT detection. Based on the number of keypoints, macroblock (MB) of frames are divided into two groups: the MB which has more features uses as an important MB group and others for non-important MB group. If the current MB is in important MB group, that MB is encoded with lower quantization parameter (QP) so the features in that MB can preserve after compression. For other MBs, the high QP is used so the overall performance is maintained. On the experiment, the effectiveness of the proposed algorithm is evaluated by comparing the SIFT similarity values between current reference software of IEEE 1857 standard with disable background modeling and proposed algorithm. According to the experimental results, our proposed algorithm can improve the SIFT Similarity values up to 49% when encoded with high target bits and Low QP in the specific important MBs based on to improve the MBs feature preservation, which is shown that the proposed algorithm outperforms to the current reference software in terms of improve SIFT similarity while maintain the same PSNR and bitrate values.
DOI: 10.14457/cu.the.2015.248
title: Recovery of valuable metals and plastics from end-of-life small home appliances by jig separation

description: Jig separation, generally used for separating particles based on density differences, is one of the oldest and most widely used methods in mineral processing due to its operation simplicity, low cost, and high efficiency. This physical separation technique has been reported to be successfully applied in the recycling of electronic wastes like home appliances and computers. In this study, the RETAC® jig was utilized to recover valuable metals and plastics from actual crushed end-of-life small home appliances after removing large pieces of metals by magnetic and eddy current separation. The study found that separation efficiency dramatically decreased with the presence of copper wires. This is due to copper wires easily getting entangled in the separation chamber during separation, where plastic and PCB particles were trapped to prevent their motion in the chamber. However, it remains unclear which factors control this entanglement process of the copper wires. To further investigate this interesting phenomenon, effects of various factors like length and amount of copper wires were investigated by using model samples of plastics and copper wires. The results showed that the higher mass ratio as well as the longer copper wires caused the more entanglement. The copper wires removal by a mill pot pre-treatment prior jig separation was also investigated for possibility to increase the separation efficiency. It was found that copper having 93% purity was firstly obtained from the pre-treatment process and the recovery efficiency in the 6th layer of jig separation increased from 66% to 87% with this pre-treatment.
DOI: 10.14457/cu.the.2015.249
title: INFLUENCE OF BURDEN ON THE ACCURACY OF CURRENT TRANSFORMER AT HIGH FREQUENCY

description: Poor quality of measurement happened when current transformer (CT) operated at high frequency, because it is typically constructed to operate only at the industrial frequency (50/60 Hz) and is not designed and tested for harmonic frequencies. Moreover, no standard provided the recommend practice for the application of CT over wide frequency range. In order to guarantee the accuracy of CT, IEC 61869-2-2012 and IEEE C57.13-2008 provided the limits of current error with the specified burden which shall have power factor of 0.8 and 0.9 lagging, respectively. Therefore, the influence of burden on the accuracy of CT over wide frequency range is investigated. This work used the several burden based on both IEC and IEEE standard burdens. The single frequency current of 10 A at frequency from 50 Hz to 1 kHz and the harmonic current up to 19th order were injected to CT. Because the value of burden was proportional to the test frequency, the author proposed two cases of burden to calculate the output current of CT. From the test results, for the first case, the ratio error corresponded to the limits of current error according to IEC 61869-2-2012 at frequency of 50 Hz. Unfortunately, the ratio error dramatically increased with increasing frequency. In second case, the high ratio error at high frequency was reduced, especially when the standard burden as manufacturer declared was the burden of CT under test. Although the ratio error in second case was acceptable according to IEC 61869-2-2012 at all test frequencies when standard burden was used, for other burden, the ratio error was slightly high. Therefore, this work used the ratio error from the single frequency current test as the correction factor (CF) to correct the ratio error. As results, the ratio error was slightly reduced.
DOI: 10.14457/cu.the.2015.250
title: APPLIED ALGORITHM FOR THE SCREENING OF NUCLEAR AND RADIOACTIVE MATERIAL OF NUCLEAR SECURITY CONCERN FROM A POORLY RESOLVED GAMMA-RAY SPECTRUM

description: Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials securing at the border control point, the detection task can present a significant challenge due to the limited measurement time, the shielding conditions and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved spectrum. In this algorithm, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of continuum background is performed by the baseline determination algorithm. Finally, the identification of radioisotope is done using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios, including single source, masking of natural uranium and enriched uranium (fresh fuel) with several radioactive sources. The novel method have better performance when compare with the commercial algorithm.
DOI: 10.14457/cu.the.2015.251
title: MEASUREMENT OF GAMMA-RAY DOSE RATE USING SMARTPHONES

description: The CMOS (Complementary Metal Oxide Semiconductor) image sensor of a smartphone has been known for its sensitivity to gamma-rays. In this research, the four models of smartphones (Samsung Galaxy GT-S5570 mini, Samsung Galaxy SII, Samsung Galaxy SIII and Huawei Ascend P7) were selected and tested for measurement of gamma-rays emitted from Iridium-192, Cobalt-60 and Cesium-137 sources. During measurements, the phones were set in video mode while the camera lenses were covered with black adhesive tape to prevent light exposure. Interaction of gamma-rays with the CMOS clearly appeared as flashing bright spots on the dark background image. The bright spots were then counted by the freely available ImageJ software. Preliminary results indicated that the number of bright spots increased linearly with increasing gamma-ray dose rate from these three sources. Among these four models of smartphone, Huawei Ascend P7 gave the highest sensitivity and the second was Samsung Galaxy SIII. Then Huawei Ascend P7 and Samsung Galaxy SIII were calibrated and tested in measurement of gamma-ray dose rate in comparison with the known values and with the dose rate survey meter. The results were very satisfactory. Application software for Android smartphones was finally developed so that the number of bright spots could be simultaneously counted and converted to gamma-ray dose rate to display on the smartphones.
DOI: 10.14457/cu.the.2015.252
title: Electrochemical immunosensor for determination of LeptospiraL LIPL32 protein

description: LipL32 is a surface membrane protein present only on pathogenic Leptospira species, which are the cause of Leptospirosis disease. As this zoonotic disease is of global importance but current diagnostic tools are still ineffective and/or inaccessible to rural areas which are affected, the need to develop an immunosensor for its detection is clear. In this work, an immunosensor for LipL32 protein was developed. Prussian blue was mixed with Graphene-PEDOT:PSS, creating Graphene-Prussian blue composite (GPB). The GPB was drop-casted on screen-printed carbon electrode (SPCE) which was later coated by Chitosan (CS) and citrate-capped gold nanoparticles (cAuNPs). The modified electrode was then further incubated with Staphylococcal protein A (PrA) and anti-LipL32 antibodies (Ab) for more sensitivity in LipL32 detection. Bovine Serum Albumin (BSA) then was used to coat the topmost layer to prevent non-specific binding of the electrode to unrelated biomolecules. The optimum electrode obtained could be used to detect LipL32 in a linear range of 50 to 200 ng ml-1 and 250 to 600 ng ml-1, lower detection limit of 54.98 ng ml-1 with RSD of reproducibility at 8.254. Furthermore, tests with intact and sonicated Leptospira interrogans cells resulted in linear range of 10 to 100 cells ml-1, lower detection limit of 44.29 cells ml-1 and 77.25 cells ml-1. The stability of the fabricated electrode also satisfactory, with only 6.79% drop in residual response current after three weeks of storage at 4°C in dried form.
DOI: 10.14457/cu.the.2015.253
title: Nuclear security policy in the context of counterterrorism in Cambodia

description: The risk of a nuclear or dirty bomb attack by terrorists is one of the most urgent and threatening dangers. The Cambodian national strategy to combat weapons of mass destruction (WMD) depicts a layered system of preventive measures ranging from securing materials at foreign sources to interdicting weapons or nuclear or other radioactive materials at ports, border crossings, and within the Cambodian institutions dealing with the nuclear security to manage the preventive programs. The aim of this thesis is to formulate guidance, to recommend the scenario of threat and risk and to provide the recommendations on additional laws on nuclear security in the context of counterterrorism by following the International Atomic Energy Agency Nuclear Security Series. The analysis in this thesis is guided by the regime theory, international laws and politics, identifying and interpreting applicable rules and norms establishing the nuclear security regime and how well enforcement of the regime is carried out and what its future reform might be. This study will examine the existing national legal frameworks of Cambodia in the context of counterterrorism to prevent acts of nuclear terrorism and the threat of a terrorist nuclear attack within the Cambodia territory. It will shed light on departmental lanes of national competent authority for nuclear security responsibility, and provide a holistic perspective on the needs of additional resources and emphasis regarding nuclear security policy in the context of counterterrorism in Cambodia.
DOI: 10.14457/cu.the.2015.254
title: Degradation of diuron via an electrochemical advanced oxidation process in a microscale-based reactor

description: Degradation of diuron, which is a toxic herbicide widely used in many countries, in aqueous solution was done in a microscale-based reactor using electrochemical advanced oxidation process (EAOP). A graphite sheet and a stainless steel were used as an anode and a cathode, respectively. Effects of pH and conductivity of the solution, applied current, and height of the microchannel, on the degradation of diuron were investigated. About 90% degradation of diuron could be achieved within 100 s of residence time in the reactor that was applied with 1 mA direct current. Moreover, the diuron degradation in water contaminated with anions, was also studied. The experimental results clearly suggested that the degradation takes place mainly by the interaction between diuron and hydroxyl radical generated via dissociation of water at the anode, although direct reduction of diuron by supplied electrons was also observed. The diuron degradation and reduction of total organic carbon (TOC) increase with increasing residence time and applied current, while the increase in the thickness of microchannel, conductivity and pH result in the decrease in diuron degradation. The ion contamination in diuron solution also reduces the degradation. All parameters directly influence the amount of hydroxyl radicals generated via EAOP. Additionally, formation and identification of intermediates were also studied by LC-MS/MS. Fifteen intermediates were identified under no anion and anion contamination. Two new intermediates were identified under nitrate ion contamination. The degradation generates many reaction intermediates, however, a simple reaction model employing 1st kinetics could represent the degradation well. Reaction pathway and mathematical model is proposed. Simulation result shows a good agreement with experimental data. Most of the degradation steps in the degradation pathway proceed at roughly the same rate that is much faster than the degradation rate achieved by other AOPs in conventional scale.
DOI: 10.14457/cu.the.2015.255
title: Designing an Effective Business Transformation Plan for Vehicle Repair Workshop

description: The main purpose of this thesis is to design and develop an effective business transformation plan for a vehicle repair workshop that operates in a competitive situation. This research will conceptually provide insight and guidance on how to transform a traditional vehicle repairs business from a management standpoint, especially by re-engineering the existing business processes in order to improve customer satisfaction. In this thesis, the principles of transformation planning can be divided into five major steps, which are 1) Initiating a research project team, 2) Understanding the current state, 3) Visioning the future of the company, 4) Creation of new business processes, 5) Determine the impact upon business performance. Regarding the internal analysis, data from customer samples and interviews with the company’s executives and staffs, it reinforces the related members to understand the capabilities and deficiencies of the business. In order to perform environmental analysis, SWOT, Porter’s 5 forces, lean consumption map and PESTLE analysis will be utilised. Besides that, the current or As-Is process is analysed in order to identify the root cause of each problem in each sub-process. Those issues are categorised into four elements, such as People, Process, Policy, and System. Indeed, high-level recommendations of the new process will be the key priorities to solve each issue and the newly proposed of the process design will be called as To-Be process. Ultimately, determining the future impacts upon the business performance and validation of the conceptual transformation plan are the best possibilities to understand the future of the business performance.