cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2012.927
title: A study of e-mail writing ability of Chiangrai Rajabhat University 4th year tourism industry students

description: This study aims to achieve three objectives including: 1) to examine the e-mail writing ability needed among personnel in Thai travel agencies; 2) to assess e-mail writing ability of Chiangrai Rajabhat University 4th year tourism industry students; and 3) to investigate the students’ e-mail writing strategies. The research instruments included a needs analysis questionnaire, three e-mail writing ability test tasks and rubrics, and an e-mail controlled retrospective interview. There were two groups of the population involved in this study. Firstly, ten travel agencies in Bangkok were recruited for the needs assessment. Secondly, twenty-nine 4th year tourism industry students at Chiangrai Rajabhat University involved in the test administration to assess their e-mail writing abilities and strategies. Questionnaire results from ten travel agencies revealed three most common e-mail tasks, and the tasks samples were analyzed using two-layer genre analysis, at the macro level, the results showed the 4-move structure, and, at the micro structure distinct linguistic features were found such as business greetings and endings, declaratives and imperatives patterns which determine the core functions and define the nature of business correspondence. The results from the needs and genre analysis were used to formulate the construct definition of the three e-mail test tasks and the rubrics to assess and evaluate the students’ e-mail writing abilities. The findings showed effective integration of Genre Analysis and Language for Specific Purposes (LSP) served its intended purpose in assessing the students’ e-mail writing ability with emphasis to the diagnostic purpose. However, the test score results were inconsistent with strategies investigation results with possible explanation that the inefficient use of strategies somewhat affected by factors involving the students’ lacks in linguistic and background knowledge. The findings showed that the e-mail writing ability constructs, tasks, and the scoring rubrics could be used as resources for e-mail writing training workshops or courses for tourism industry students and other areas of Language for Specific Purposes.
DOI: 10.14457/cu.the.2012.928
title: Effect of impurities in ethylene gas on the catalytic activity of ziegler-natta catalyst and polyethylene properties

description: In this current study, the various types of impurity, which were mostly found in ethylene gas, were used to investigate the influence of impurities on the catalytic activity of a commercial Ziegler-Natta catalyst and polyethylene properties. A desired amount of impurities was injected during ethylene polymerization both in the absence and presence of hydrogen. In the absence of hydrogen, CO, CO₂ and CH₄ poisoned to the catalyst resulting in a decrease in the activity, while C₃H₆ and C₂H₂ enhanced the activity causing from the copolymerization with ethylene. In the presence of hydrogen, hydrogen was differently affected on impurities. It had a beneficial effect in the case of CO. While other compounds exhibited the results in the opposite side. The effects of H₂O and CH₃OH were varied relying on their quantities and operating condition. Hydrogen also gave a beneficial effect on the activity as well. The effects of impurities on ethylene consumption and catalyst decay rate between in the absence and presence of hydrogen were also investigated in this study. Moreover, our studies have been found that impurities reduced Mw and narrow MWD, but they did not affect on the thermal behavior of polyethylene.
DOI: 10.14457/cu.the.2012.929
title: Removal of the mixture of tributyltin and tetrachloroethylene using microemulsion technique couple with neutral buoyancy concept

description: This research studied the feasibility of using microemulsion technique couple with neutral buoyancy concept to remove the mixture of tributyltin (TBT) and tetrachloroethylene (PCE) from subsurface system. TBT is a hazardous organometal and was used as a biocidal paint to prevent barnacle adhesion to marine vessel. TBT was usually used as a mixture so this study used it as a mixture with PCE which was a common organic solvent so it was likely to be found coexisting with other organic contaminant. Both TBT and PCE are dense non aqueous phase liquid (DNAPL), therefore prevention of downward migration had to be considered when carrying out the removal process. Addition of alcohol was selected as a means to adjust the density of the contaminant to be closed to that of the surrounding water. Hence, most of the experiments in this study were carried out in the presence of alcohol. Major finding in this research were as follows. Hydrophobicity of organometallic under study, tributyltin (TBT), was characterized as an equivalent alkane carbon number (EACN) and was determined to be 11.17 by using Salager’s equation and linear mixing rule. The TBT-PCE mixture under focused was the mixture of 60 wt% TBT with 40 wt% PCE and had its EACN calculated to be 6.5 which was closed to the EACN of tetraethylead, another important organometal. The surfactant system selected for detail investigation was the system of 3.6 wt% SDHS + 0.4 wt% C16 DPDS at 3wt% NaCl (4 wt% total surfactant) with two alcohol types, n-butanol (BuOH) and tert-butanol (TBA). The study was conducted in both batch and continuous flow study by focusing on the removal of TBT and PCE and the density modification of mobilized NAPL. Performance of different alcohol and surfactant concentration were studied. In the continuous flow study, the flushing schemes were explored for both single step flushing which compared between the surfactant system with and without alcohol addition and two-step flushing which used only alcohol addition in the first step to adjust the density and added surfactant in the second step to reduce interfacial tension. Results from six column studies showed that the most efficient system for removal of TBT and PCE while having the density of mobilized NAPL lower than surrounding aqueous phase was the system with two- step flushing with saturated BuOH. The system was preflushed with saturated BuOH solution with 3 wt% NaCl and followed by 3.6 wt% SDHS + 0.4 wt% C16 DPDS at 3wt% NaCl saturated with BuOH. The main removal mechanism was mobilization at which 82.09% of TBT and 85.23% of PCE from total removal was removed as light nonaqueous phase liquid (LNAPL). There was some small DNAPL mobilization occurred but the density was already modified to1.063 mg.L-1, and it was accounted for 13.24% for TBT and 5.74% for PCE from their total removal. The total applied flushing solution was 40 times of the volume between pore space of the sand packed in the column.
DOI: 10.25550/v90
title: microCT - Bone Tissue of Smad4fl/fl control at E18.5

description: This dataset includes 1 microCT scan of the skull of a Smad 4fl/fl mouse at E18.5. The scan is in NiFTI format. See Help section for a list of free applications to view files in NiFTI format
DOI: 10.25550/v9m
title: Skull vault formation in individual wildtype AB fish

description: An individual fish was imaged successively from 10-15 dpf by confocal microscopy, during the period of induction and growth of the frontal and parietal bones. The fish was transgenic for col1a1a:gfp, marking chondrocytes, and for sp7:mcherry, marking osteoblasts.
DOI: 10.25550/vap
title: Skull vault formation in individual wildtype AB fish

description: An individual fish was imaged successively from 10-21 dpf by confocal microscopy, during the period of induction and growth of the frontal and parietal bones. The fish was transgenic for col1a1a:gfp, marking chondrocytes, and for sp7:mcherry, marking osteoblasts.
DOI: 10.25550/vq6
title: microMRI images of skulls of Smad4F mice at E13.5

description: microMRI images of skulls of Smad4F mice at E13.5. The dataset contains 3-D images in niftii format for each of 2 mice.
DOI: 10.25550/vqm
title: Gene expression microarray - mouse E9.5 Otic Vesicle

description: Gene expression microarray using tissue obtained by laser capture microdissection (LCM) from the Otic Vesicle of mouse embryos at E9.5
DOI: 10.25550/vqy
title: Skull vault formation in individual WT AB Fish

description: An individual fish was imaged successively from 11-25 dpf by confocal microscopy, during the period of induction and growth of the frontal and parietal bones. The fish was transgenic for col1a1a:gfp, marking chondrocytes, and for sp7:mcherry, marking osteoblasts.
DOI: 10.25550/vv6
title: microMRI images of skulls of Tgfbr2fl/+ * Alk5fl/fl mice at E18.5

description: microMRI images of skulls of Tgfbr2fl/+ * Alk5fl/fl mice at E18.5. The dataset contains 3-D images in niftii format for 1 mouse.
DOI: 10.25550/vy8
title: Transgenic Mouse Enhancer OPT Assays - mm1215

description: ChIP-seq, RNA-seq and transgenic assays to identify non-coding regulatory elements (enhancers) active during craniofacial development
DOI: 10.5519/qd.0eocv29o
title: Query on the Natural History Museum Data Portal (data.nhm.ac.uk) (297 records)
DOI: 10.14457/cu.the.2012.930
title: Real-time monitoring of inter-area power oscillation using phasor measurement units

description: The stability problem of inter-area power oscillation may cause system blackout. Due to continuously changing of power system operating condition, it makes such stability problem difficult to observe. Real-time monitoring of inter-area power oscillation will play an important role in maintaining the power system stability. This thesis proposes real-time monitoring system of inter-area power oscillation stability by identifying predominant modes of oscillation as well as the associated mode damping and mode shape. The identification process is based on PMU data with preprocessing technique consisting of detrending and downsampling. The Modified Yule-Walker (MYW) algorithm is utilized for identifying frequency of oscillation and mode damping while combined Power Spectral Density (PSD) and Cross Spectral Density (CSD) are used for mode shape identification. In addition, the real-time monitoring system is equipped with operational recommendation options to provide the operator with guidelines to improve Power Oscillation Damping (POD). The recommendation is established based on the concept of mode sensitivity analysis. These identification results are then displayed on GUI to assist the power system operator to monitor system condition in real-time. The simplified 17-machine Western North American power grid system is used to verify the monitoring system performance. The results show that the proposed real-time monitoring system is able to accurately track the predominant modes of oscillation as well as to provide the system operator with recommendation for to improve power system damping. The real-time monitoring system works well during both ambient and ringdown conditions.
DOI: 10.14457/cu.the.2012.931
title: Hydrogen production via chemical looping reforming on NiO/CeO₂

description: This work focuses on the production of hydrogen from methane via the chemical looping reforming process, where NiO was used as the oxygen storing species. The study involved simulation of this process using a simulation package, Aspen Plus and laboratory experiments. The simulation work considered a conventional chemical looping process and a sorption enhanced chemical looping process, with the aim of finding appropriate operating conditions for the production of high purity hydrogen gas with low energy process requirements. The experimental work involved the loading of NiO on two different supports, CeO₂ and Al₂O₃, used in conventional chemical looping and sorption enhanced chemical looping operated under both combined combustion as well as reforming processes. Experiments were conducted in a fixed-bed reactor operating at 1 bar and 600°C. NiO was used as a solid oxygen carrier which in this process is reduced by methane and subsequently oxidized by air in a cyclic process. In the chemical looping combustion experiments, methane was fed as a reactant at a rate of 2x10⁶ mol/s (3 cm³(NTP)/min), and in the chemical looping reforming experiments, methane was fed at a rate of 2x10-⁶ mol/s (3 cm³(NTP)/min) and steam at a rate of 4x10-⁶ mol/s (6 cm³(NTP)/min). The results show a higher production rate of hydrogen with NiO/CeO₂ than for NiO/Al₂O₃. This result is explained by the higher oxygen storage capacity of CeO₂ which promotes the partial oxidation of methane. In addition, a higher hydrogen gas purity and a higher methane conversion were observed in the presence of CaO.
DOI: 10.14457/cu.the.2012.932
title: Mixed integer model for glass container production scheduling

description: This thesis proposes the production planning and scheduling mathematical programming model for the glass container industry. A furnace distributes glass to a set of parallel machines for forming products, where machine-dependent setup time and cost are incurred for switching overs from one product to another. This thesis states the formulation of a mixed-integer programming model using a goal programming for minimizing the setup time and makespan. The SAGE mathematical model was constructed and solved for the optimal solution. The performances of the mixed-integer programming model are compared with the current production scheduling from the company in Thailand. The computational results exhibit better setup time than the current plan.
DOI: 10.14457/cu.the.2012.933
title: 2-Absorbing and weakly 2-absorbing subsemimodules over commutative semirings

description: In this thesis, we study 2-absorbing, weakly 2-absorbing, AG2-absorbing and weakly AG2-absorbing subsemimodules of semimodules over commutative semirings. Those are extended from prime, weakly prime, primary and weakly primary subsemimodules, respectively. Some characterizations of 2-absorbing, weakly 2-absorbing, AG2-absorbing and weakly AG2-absorbing subsemimodules are obtained. Moreover, we investigate relationships between 2-absorbing, weakly 2-absorbing, AG2-absorbing and weakly AG2-absorbing subsemimodules of semimodules over commutative semirings and 2-absorbing, weakly 2-absorbing, AG2-absorbing and weakly AG2-absorbing ideals of the same semirings. Finally, we obtain necessary and sufficient conditions of a semimodule in order to be a top semimodule.
DOI: 10.14457/cu.the.2012.934
title: Zero-mean functional equation on planar N-gons

description: In this thesis, we establish the general solutions to the zero-mean functional equation on planar n-gon with the constraint that for each planar n-gon obtained by translations and dilations of an arbitrary fixed n-gon, the sum of the values of at all vertices is zero. In particular, we will determine the general solution to the zero-mean functional equation.
DOI: 10.14457/cu.the.2012.935
title: The attenuation of treatment couch in advance radiotherapy techniques

description: To study the dosimetric parameters influenced in Exact couch and the Exact IGRT couch attenuation and to determine the effect in conventional, IMRT and VMAT treatment techniques. The dose measurements were employed in both energies of 6 MV and 10 MV photon beams with field sizes of 3×3 cm², 5×5 cm², 10×10 cm², and 20x20 cm² for various gantry angles around the treatment couch at cranial, middle and caudal couch position. The effect of couch attenuation in conventional, IMRT and VMAT treatment techniques were investigated. The maximum attenuation was detected at 6 MV with the smallest field for all couch positioning setups. The Exact couch showed maximum attenuation of 18.5% for 6 MV and 14.7% for 10 MV at 170 and 190 degree at rail in and cranial couch position, while the Exact IGRT couch presented the maximum attenuation of 5.1% for 6 MV and 5.0% for 10 MV at 140 and 220 degree at caudal position for 3x3 cm² field size. The maximum percent dose differences between measurement and calculation without couch consideration for 6 MV in parallel opposing fields of chest treatment were 7.96% for Exact couch at rail in position and 2.29% from single field PA spine treatment for IGRT couch. The percent dose differences in IMRT plans between measurement and calculation without couch were varied from 2.67% to 5.89% for Exact couch and 0.67% to 3.25% for Exact IGRT couch. While VMAT plans presented the deviation from 2.87% to 4.73% for Exact IGRT couch. The percent dose differences between measurement and calculation with couch were smaller than without couch for all techniques study. The effect from beam attenuation by the treatment couch is significant for patients treated with posterior or oblique posterior fields. The dose deviation due to couch attenuation of Varian couch depends on the field size, angle beam, energy, couch position and type. Therefore, patients should be avoided from the beam pass directly through rail position in posterior and posterior oblique or the correction should be included in treatment planning systems.
DOI: 10.14457/cu.the.2012.936
title: Solving linear programming problem with uncertainty : probability interval and random set parameters

description: In this thesis, we concentrate on the relationship of probability intervals and random sets. Furthermore, we are interested in solving uncertain linear programming problems with probability interval and random set parameters. We discover the conditions to verify when a given probability interval obtains the same information as a random set information. If these conditions are satisfied, we can transform a problem that contains both types of uncertainty into a problem which has only the random set information. In addition, we use an idea from decision making theory with random sets for solving this problem. If a probability interval does not satisfy these conditions, we can solve the problem for finding the optimistic and pessimistic expected recourse values. Finally, we present an algorithm for checking these conditions and constructing appropriate distributions for each of the optimistic and pessimistic approaches.
DOI: 10.14457/cu.the.2012.937
title: Estimation of surface dose from therapeutic 6 MV photon beams

description: Accurate assessment of surface dose from therapeutic photon beam can lead to predict the skin reaction and design the radiation treatment technique. Many common dosimeters have been used to estimate the surface dose. However, they are known to over-response in the near surface region. In this study, the surface dose at the central axis of 6 MV photon beams from Varian Clinac 23EX medical linear accelerator was investigated using both measurement and simulation. The photon beams are in square and rectangular shape with the side ranging from 3 to 25 cm defined by the collimators. The measurements were taken using four detectors: TLD chip, PFD[superscript 3G] diode, Markus parallel-plate and CC13 cylindrical ionization chamber. The EGS4nrc Monte Carlo (MC) code was used in the simulation. The surface dose was obtained from an extrapolation of absorbed dose in the near surface region. It was found to be significantly increased almost linearly with the increasing square field size from both measured and simulated results. As expected, the surface dose from the measurement was higher than the simulated result. The lowest and highest over-responses in the surface dose measurement, compared with MC simulation, were found with the TLD chip and the CC13 chamber, respectively. Using the MC result as a gold standard, the correction factors for each dosimeter for estimating the surface dose from square photon beam with the side between 5 to 20 cm were introduced. For the rectangular field, its surface dose can also be obtained from that of the square field using the equivalent square approach. Specifically, the side of the equivalent square of rectangular field was computed using the area-to-perimeter formula. In the comparison between the percentage surface dose of rectangular field and that of the relevant equivalent square, the difference was found to be clinically negligible. Moreover, the influence of collimator scatter on the surface dose was also found to be insignificant. Hence, the surface dose of various rectangular fields from therapeutic photon beam can be predicted reliably using the approach proposed in this study.
DOI: 10.14457/cu.the.2012.938
title: Maximum allowable distributed generation with consideration of fault ride through requirement and utility protection system

description: Distribution systems are changing from one-source supplying structure into multi-source supplying structure with participations of distributed generations. The strong increase in number of renewable-based generating plants, with the advanced control technology, impulses their role in power systems. Using a package of an asynchronous generator along with an inverter to synchronize the output with the power system is an upward tendency for generating units in these plants. Such generating unit is known as an inverter-based distributed generation. Besides, many combined heat and power plants using synchronous generators are still used in power systems and named synchronous machine-based distributed generation. From distributed generation’s owner perspectives, the renewable energy should be exploited; hence, the installation capacity of the distributed generation is expected to be as large as possible. However, the installation of distributed generation may violate system operating limits such as substation and line capacities, voltage limits and causes other impacts dealing with protection system operation.This thesis considers typical problems such as system operating limits, reach reduction of utility relay, and fault ride through requirement from distribution system operators in order to maximize distributed generation’s installation. Fault responses of the inverter-based distributed generation to a fault in the network are characterized with consideration of fault ride through requirement of the distribution system operators. Based on the obtained characteristics, a new model of the inverter-based distributed generation is proposed. This model is convenient for an adaptive fault calculation algorithm which is to estimate fault currents in the system for setting and checking the operation of protection system. This fault calculation algorithm is then employed by an algorithm proposed for maximizing distributed generation. The IEEE 34 Node Test Feeder is then used to illustrate the effectiveness of the algorithm in determining the maximum distributed generation installed in this system.