Thailand Research Articles

Multiscale modeling and integration of a combined cycle power plant and a two-tank thermal energy storage system with gPROMS and SimCentral

With different computational tools, simulations ranging from detailed and rigorous mathematical models to overall process plant of black box models can be carried out. Whereas most of these computational tools cannot practically execute different scales of models at the same time, it becomes relevant to devise strategies in coupling two or more of them for better analysis of processes. In this light, this study proposes Excel as an interactive scale bridge of data exchange to aid the multiscale modeling and dynamic simulation of combined cycle (CC) power plant integration with two-tank thermal energy storage (TES) system using gPROMS and SimCentral. This is relevant to analyze not only the performance of TES, but the feasibility of its integration with CC in augmenting energy production to meet daily power demand. The integrated system modeled in four operational modes of CC increased in power generation by 7.3 MW at an efficiency of 98.30%. The study validated the usefulness of the TES integration of 99.66% efficiency. The research results provide a communication strategy for different computational tools and an approach to effectively increase CC power production to meet varying daily demand.

Emerging Ideology of Commercial State in Thailand

In the 2017 Constitution of Kingdom of Thailand there was a call to create a National Strategy of the country’s development. The 20-year National Strategy was adopted in October 2018 by the National Council for Peace and Order. A major part of this strategy deals with the problem of Thai provinces’ separatist movements and increasing Bangkok’s political and social control. To achieve these goals, a new ideology of “commercial nation” was created that contrasts with the more traditional “community democracy” approach. While the ideology of commercial state may be a useful vehicle for urbanising Thai provinces in the future, conquering separatist trends and articulating new priorities for the Thai population, it is still pure ideology and it cannot be applied practically in the form in which it was formulated. However, the “commercial state” ideology may be an instructive example of new techniques for social unifying people in developing countries.

LEANING PAGODA OF AYUTTHAYA ANALYSIS WITH THREE-DIMENSIONAL EFFECTS AND GROUND UNCERTAINTY

The pagoda of Wat Krasai, built in the 17th century on the outskirts of the Ayutthaya district in the Kingdom of Thailand, tilts approximately 2° to the north and may continue to tilt further. The cause of this tilt is thought to be the uneven settlement of the foundation ground, but no supporting evidence has been presented. Three cohesive soil layers that may cause uneven settlement have been confirmed in the foundation ground around the pagoda, but soil tests are inadequate, leading to uncertainty in proving the cause of inclination. Hence, the cause of inclination was investigated in this study by calculating the inclination that can occur within the realistic ranges of the soil properties through numerical analysis using the finite element method. A method of correcting plane strain analysis, which has a low computational cost, with a three-dimensional effect coefficient, was utilized to assess over 500 cases considering ground material uncertainties, and the probability distribution of the possible inclinations was calculated. This method is useful as it considers fluctuations in the ground material parameters to address land settlement, which is largely influenced by the three-dimensional effects. This approach will also be applicable to future predictions aimed at pagoda preservation.

Development of catalytic combustion and CO2 capture and conversion technology

Changes are needed to improve the efficiency and lower the CO2 emissions of traditional coal-fired power generation, which is the main source of global CO2 emissions. The integrated gasification fuel cell (IGFC) process, which combines coal gasification and high-temperature fuel cells, was proposed in 2017 to improve the efficiency of coal-based power generation and reduce CO2 emissions. Supported by the National Key R&D Program of China, the IGFC for near-zero CO2 emissions program was enacted with the goal of achieving near-zero CO2 emissions based on (1) catalytic combustion of the flue gas from solid oxide fuel cell (SOFC) stacks and (2) CO2 conversion using solid oxide electrolysis cells (SOECs). In this work, we investigated a kW-level catalytic combustion burner and SOEC stack, evaluated the electrochemical performance of the SOEC stack in H2O electrolysis and H2O/CO2 co-electrolysis, and established a multi-scale and multi-physical coupling simulation model of SOFCs and SOECs. The process developed in this work paves the way for the demonstration and deployment of IGFC technology in the future.

Do Words in Central Bank Press Releases Affect Thailand's Financial Markets?

Do Words in Central Bank Press Releases Affect Thailand's Financial Markets?

A case of disjunct montane linyphiid species (Araneae) in the Palaeotropics, with notes on synonymy and the description of a new species

The genus EnguterothrixDenis, 1962 contains two very closely related species on different continents: E. crinipesDenis, 1962, known from the mountains of the Democratic Republic of the Congo, and E. simpulum (Tanasevitch, 2014) comb. nov. (transferred from ApophygoneTanasevitch, 2014), which is widespread in the mountains of northern Thailand. Enguterothrix fuscipalpisDenis, 1962 is removed from the genus and preliminarily placed in MicrargusDahl, 1886. A new species, Oedothorax paralegrandi sp. nov., is described from the Indian Himalayas; it shows close relations to the Afrotropical O. legrandiJocque, 1985 from the Comoros. The following new synonyms are proposed: ApophygoneTanasevitch, 2014 syn. nov. of EnguterothrixDenis, 1962; Enguterothrix tenuipalpisHolm, 1968 syn. nov. of Enguterothrix crinipesDenis, 1962; Nasoonaria circinataZhao & Li, 2014 syn. nov. of Nasoonaria magnaTanasevitch, 2014; Theoa bidentataZhao & Li, 2014 syn. nov. of Theoa elegansTanasevitch, 2014.

Si bilayer tunnel field-effect transistor structure realized using tilted ion-implantation technique

A new device structure for the Si tunnel field-effect transistor (TFET) is proposed along with feasible fabrication processes. The device consists of a Si fin with high impurity concentration at the fin surfaces, which are realized using the tilted-ion-implantation technique (TII) to effectively generate the gate-normal band-to-band tunneling (BTBT) and simultaneously create carrier conduction paths from the source to the drain. Device simulation revealed that the asymmetric impurity distribution, with a higher concentration on the source side and a lower concentration on the drain side controlled by the TII energy and angle, has potential for the realization of a high eGR/hGR by reducing the BTBT distance and a low off-state leakage. As a result, a steep on/off switching with a current ratio greater than 105 under an operating voltage of 0.3 V can be achieved by careful optimization of the implanted impurity distributions.

Influence of Ethnicities in Thai Drama

This article aims to study the influence of ethnicities in Thai drama. The scope of the study focuses on ethnic groups that appeared in the Three Seals Law. The study method is a mixed method, and the results are presented by descriptive analysis. The study revealed that, Thai drama was recorded in the official legal document and performed for rituals, ceremonies, entertainment, education, occupations, publication of government policies, and in community identity. The early stories of Thai drama were about the local people, combined with ethnic cultures that had played an important role in the Kingdom of Thailand, as appeared in the Three Seals Law, namely, Mon, Lao, Vietnamese, Cham, Chinese, Khaek, Javanese, Malay, Khmer, Dawei, Burmese, Japanese, and Farang. The influence of the ethnic groups found in Thai drama is shown in the stories, characters, formats, contents, lyrics, musical instruments, musical accents, costumes, postures, stage, props, role performance, acting methods, and performance opportunities. The drama was used as a communication tool for leaders, symbol of honor for royalties, and the presentation of the kingdom’s image. The influence of the ethnic groups that appear in Thai drama has been passed on and developed continually and finally created their own identity as evidenced in the present educational curriculum and performances.

Vertical MBE growth of Si fins on sub-10 nm patterned substrate for high-performance FinFET technology* *Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0200504) and the National Natural Science Foundation of China (Grant No. 61927901).

A high quality epitaxial Si layer by molecular beam epitaxy (MBE) on Si (001) substrates was demonstrated to fabricate a channel with low density defects for high-performance FinFET technology. In order to study the effects of fin width and crystallography orientation on the MBE behavior, a 30 nm thick Si layer was deposited on the top of an etched Si fin with different widths from 10 nm to 50 nm and orientations of 〈100〉 and 〈110〉. The result shows that a defect-free Si film was obtained on the fin by MBE, since the etching damage was confined in the bottom of the epitaxial layer. In addition, the vertical growth of the epitaxial Si layer was observed on sub-10 nm 〈100〉 Si fins, and this was explained by a kinetic mechanism.

Energy Scaling and Asymptotic Properties of One-Dimensional Discrete System with Generalized Lennard-Jones (m, n) Interaction

It is well known that elastic effects can cause surface instability. In this paper, we analyze a one-dimensional discrete system which can reveal pattern formation mechanism resembling the “step-bunching” phenomenon for epitaxial growth on vicinal surfaces. The surface steps are subject to long-range pairwise interactions taking the form of a general Lennard-Jones (LJ)-type potential. It is characterized by two exponents m and n describing the singular and decaying behaviors of the interacting potential at small and large distances, and henceforth are called generalized LJ (m, n) potential. We provide a systematic analysis of the asymptotic properties of the step configurations and the value of the minimum energy, in particular their dependence on m and n and an additional parameter \(\alpha \) indicating the interaction range. Our results show that there is a phase transition between the bunching and non-bunching regimes. Moreover, some of our statements are applicable for any critical points of the energy, not necessarily minimizers. This work extends the technique and results of Luo et al. (SIAM Multiscale Model Simul 14(2):737–771, 2016) which concentrates on the case of LJ (0,2) potential (originated from the elastic force monopole and dipole interactions between the steps). As a by-product, our result also leads to the well-known fact that the classical LJ (6,12) potential does not demonstrate the step-bunching-type phenomenon.

Another Promising HIV Vaccine Fails

The modest preventive efficacy seen in the RV144 vaccine trial in Thailand prompted an investigation of the recombinant canarypox vector (ALVAC-HIV)

Effect of Lean Practices on Innovation Skills of Pharmaceutical organizations in Thailand

Lean practices are crucial to decrease wastages and enhance the quality of pharmaceutical products by the implementation of lean strategies and standardization method in production. However, there is a need to sustain the effectiveness of such strategies by developing the innovation skills of employees. Thus, the core objective of this study to investigate the effect of lean practices on employees’ innovation skills of pharmaceutical firms in Thailand. To investigate the proposed relationship among the variables and hypotheses testing, data was collected from the 350 employees of pharmaceutical firms in Thailand. Collected data was analysed by applying PLS software. This study found that lean strategies have positive influence on innovation skills of pharmaceutical firms’ employees. Standardization also has significance effect on innovation skills of pharmaceutical firms’ employees. Findings of this study offer new insight to the policymakers of pharmaceutical industry. Results of this study exemplified howinnovation skills of employees in pharmaceutical organizations can improve by the implementation of lean practices.

Effect of Technology Capabilities on Sustainable Performance of Pharmaceutical firms in Thailand with moderating role of Organizational Culture

Sustainable performance is necessary for long term existence of any business. Implementation of technology capabilities play important role in sustainable performance of any organization and especially for pharmaceutical firms. Therefore, the basic objective of current study was to examine the influence of technology capabilities (Technical Science, Level of Skills and Physical tools) on sustainable performance of pharmaceutical firms in Thailand with moderating role of organizational culture. To accomplishthe purpose of study, the quantitative research approach with cross sectional method was adopted. This study found that technology capabilities have significant influence on sustainable performance of any organization and especially for pharmaceutical firms. Study also found significant moderating role of organizational culture between the relationship level of skills and physical tools with sustainable performance of any organization and especially for pharmaceutical firms. This study offers new information to the management regarding decision-making process. The findings will assist top management in planning for sustainable performance, implementation of technology and organization culture, especially in the context of pharmaceutical firms in developing countries

Assessment of a detailed biomass pyrolysis kinetic scheme in multiscale simulations of a single-particle pyrolyzer and a pilot-scale entrained flow pyrolyzer

A detailed biomass pyrolysis kinetic scheme was assessed in the multiscale simulations of a single-particle pyrolyzer with slow pyrolysis and a pilot-scale entrained flow pyrolyzer with fast pyrolysis. The detailed kinetic scheme of biomass pyrolysis developed by the CRECK group consists of 32 reactions and 58 species. A multiscale simulation model was developed, where the CRECK kinetics was employed to simulate biomass pyrolysis reactions, a one-dimensional particle model was utilized to simulate the intraparticle transport phenomena, and the particle-in-cell (PIC) model was employed to simulate the hydrodynamics. The multiscale model was first applied to simulate a single-particle pyrolysis experiment. The simulation with nonisothermal particles matched the experimental data better than the simulation with isothermal particles. Then the multiscale model was applied to simulate the pilot-scale entrained flow pyrolyzer. In this case, the simulation with isothermal particles matched the experimental data better than the simulation with nonisothermal particles. The reason for this difference might be that the kinetics itself already partially included the intraparticle transport effect as it was fitted using both TGA data (slow pyrolysis of small size biomass) and fluidized bed data (fast pyrolysis of relatively large size biomass). This study provides some insights into biomass pyrolysis kinetics development and pyrolyzer multiscale simulation for a future study.

Apparent size effects on dopant activation in nanometer-wide Si fins

Due to the dramatic downscaling of device features in recent technology nodes, characterizing the electrical properties of these structures is becoming ever more challenging as it often requires metrology able to probe local variations in dopant and carrier concentration with high accuracy. As no existing technique is able to meet all requirements, a correlative metrology approach is generally considered a solution. In this article, we study size-dependent effects on the dopant activation in nanometer-wide Si fins using a novel correlative approach. We start by showing that the micro four-point probe technique can be used to precisely measure the resistance of B doped and (laser) annealed Si fins. Next, we use transmission electron microscopy and scanning spreading resistance microscopy to show that the observed width dependence of the apparent sheet resistance of these fins can be explained by either a partially or a fully inactive region forming along the top of the fin sidewalls according to the annealing conditions.

Impact of Chemical Pesticides Use in a Social Accounting Matrix Framework: A Case Study of Thailand

Impact of Chemical Pesticides Use in a Social Accounting Matrix Framework: A Case Study of Thailand

Data-driven discovery of coarse-grained equations

Statistical (machine learning) tools for equation discovery require large amounts of data that are typically computer generated rather than experimentally observed. Multiscale modeling and stochastic simulations are two areas where learning on simulated data can lead to such discovery. In both, the data are generated with a reliable but impractical model, e.g., molecular dynamics simulations, while a model on the scale of interest is uncertain, requiring phenomenological constitutive relations and ad-hoc approximations. We replace the human discovery of such models, which typically involves spatial/stochastic averaging or coarse-graining, with a machine-learning strategy based on sparse regression that can be executed in two modes. The first, direct equation-learning, discovers a differential operator from the whole dictionary. The second, constrained equation-learning, discovers only those terms in the differential operator that need to be discovered, i.e., learns closure approximations. We illustrate our approach by learning a deterministic equation that governs the spatiotemporal evolution of the probability density function of a system state whose dynamics are described by a nonlinear partial differential equation with random inputs. A series of examples demonstrates the accuracy, robustness, and limitations of our approach to equation discovery.

Microscopic residual stresses analysis and multi-objective optimization for 3D woven composites

To balance the conflict between low cost and high quality of 3D woven composites (3DWC), we develop a multi-objective optimization methodology. A multiscale process simulation model is proposed to calculate microscopic residual stresses in 3DWC, and the model is validated by experimental measurement using fiber Bragg grating sensors. To address the enormous computational amount, a surrogate model is constructed through three sequential sampling algorithms called Monte Carlo based space reduction, cross-validation Voronoi and greedy algorithm. An interface is developed to integrate the process simulation, sequential sampling and optimization. The multi-objective optimization is conducted to minimize residual stresses and process time utilizing a genetic algorithm, and the Pareto front is obtained. The global sensitivity analysis is conducted based on the surrogate model, and the key parameters are identified. The results show that the effects of process parameters on objectives are coupled. The overall cure cycle should be considered in process optimization.

Community Forest Carbon Assessment in Eastern Thailand from Forest Conservation Management by Local People

One measure of increasing carbon sequestration areas is community forest conservation, which is the way to maintain common forest areas linking with human livelihoods. The first step towards implementing incentive mechanism of Reducing Emissions from Deforestation and Degradation (REDD) at the national level is to assess the amount of forest carbon. This is important for REDD inspections and subsequent funding from public funds or carbon markets. The objective is to find the carbon stock in soil, aboveground and belowground biomass for estimated carbon price in the community forest. The study site was carried out at Ban Phrao community forest, Sa Kaeo Province, East of Thailand. Field data were collected from temporary 16 plots the diversity of plant species, to assess forest biomass carbon storage based on the allometric equation, and to estimate the proportion of carbon contents in plant and soil by using CHN analyzer.

Effect of Biochar on Red Chili Growth and Production in Heavy Acid Soil

The addition of biochar to soil has been suggested as an environmentally friendly method to enhance soil properties and carbon sequestration and plant production; however, the effects of biochar on root growth and crop production in heavy acid soil is not fully understood. This study evaluated the effects of corn cob biochar on the growth and production of red chili (Capsicum annuum L.) in heavy acid soil in Thailand. The soil properties, aboveground and belowground biomasses, fruit dry weight, and fine root length growth and senescence were compared between two biochar conditions, B1 (6.25 t ha-1) and B2 (12.5 t ha-1), and a heavy acid soil control (CF).