• Korean Institute of Interior Design Journal
• /
• v.17 no.3
• /
• pp.51-58
• /
• 2008

Lately, in public libraries, there are various service programs for child user by corresponding to importance of reading based education and also a variety of changes by accommodating family based cultural life style. Therefore there is a need for space planning based study on unit-data room. This study gives guide-line of space planning through categorizing of space plot and furniture lay-out in child data room. The researcher, as a first step, searched web sites of 29 data rooms of 26 libraries and summarized space plots and features of data rooms through in-person visits. Then the author made a categorization standard and did a general analysis of featured data rooms through multiple categorization steps. There are Basic Type, General Type, Book-Shelf Centered Type, Book-shelf Scattered type and Multi-Functional Type out of this categorization steps. In sum, six categorizing bases, dividing infant room from child room, space zonning, position of entrance, compactness of reading space, position of book-shelf and orientation of book-shelf will be important design standards for child data-room of future libraries and an effective guide-lines for other unit data-rooms.

• Wind and Structures
• /
• v.33 no.6
• /
• pp.437-446
• /
• 2021

As wind turbine rotors increase, the overall loads and dynamic response become an important issue. This problem is augmented by the exposure of wind turbines to severe atmospheric events with unconventional flows such as tornadoes, which need specific designs not included in standards and codes at present. An experimental study was conducted to analyze the loads induced by a tornado-like vortex (TLV) on horizontal-axis wind turbines (HAWT). A large-scale tornado simulation developed in The Wind Engineering, Energy and Environment (WindEEE) Dome at Western University in Canada, the so-called Mode B Tornado, was employed as the TLV flow acting on a rigid wind turbine model under two rotor operational conditions (idling and parked) for five radial distances. It was observed that the overall forces and moments depend on the location and orientation of the wind turbine system with respect to the tornado vortex centre, as TLV are three-dimensional flows with velocity gradients in the radial, vertical, and tangential direction. The mean bending moment at the tower base was the most important in terms of magnitude and variation in relation to the position of the HAWT with respect to the core radius of the tornado, and it was highly dependent on the rotor Tip Speed Ratio (TSR).

• Wind and Structures
• /
• v.34 no.3
• /
• pp.303-312
• /
• 2022

As wind turbine rotors increase, the overall loads and dynamic response become an important issue. This problem is augmented by the exposure of wind turbines to severe atmospheric events with unconventional flows such as tornadoes, which need specific designs not included in standards and codes at present. An experimental study was conducted to analyze the loads induced by a tornado-like vortex (TLV) on horizontal-axis wind turbines (HAWT). A large-scale tornado simulation developed in The Wind Engineering, Energy and Environment (WindEEE) Dome at Western University in Canada, the so-called Mode B Tornado, was employed as the TLV flow acting on a rigid wind turbine model under two rotor operational conditions (idling and parked) for five radial distances. It was observed that the overall forces and moments depend on the location and orientation of the wind turbine system with respect to the tornado vortex centre, as TLV are three-dimensional flows with velocity gradients in the radial, vertical, and tangential direction. The mean bending moment at the tower base was the most important in terms of magnitude and variation in relation to the position of the HAWT with respect to the core radius of the tornado, and it was highly dependent on the rotor Tip Speed Ratio (TSR).

• SUVANNABHUMI
• /
• v.11 no.1
• /
• pp.7-40
• /
• 2019

The essay reflects on the work of Adrian Lapian (1929-2011), an Indonesian scholar of archipelagic/maritime Southeast Asia and its "sea people-sea pirates-sea kings." The essay suggests that Lapian's writing mirrors navigation at sea, and the constant re-orientation and ever-changing, multiple points of view that are part of it. This is contrasted to Foucault's "panopticism" and academic desire for discipline. Taking cue from Lapian's writing and from the present author's experience of seafaring, the essay envisions Southeast Asian studies as a fluid, precarious, disorienting, even nauseating multiplicity of experiences, dialogues, and moving, unstable, and uncertain points of view; a style of learning that is less (neo)colonial, more humble, and closer to experiences in the region, than super-scholarship that imposes universalizing, panoptic standards, theories and methods (typically self-styled as "new") that reduce the particular into a specimen of the general, a cell in the Panopticon. The essay concludes with reflections on certain learning initiatives/traditions at the National University of Singapore, including seafaring voyages-experiences, encounters, and conversations that make students and scholars alike to move and see differently, to be touched, blown away, rocked, swayed, disoriented, swallowed, transformed, and feel anew their places, roots, bonds, distances, fears, blindness, powerlessness.

• Electronics and Telecommunications Trends
• /
• v.38 no.6
• /
• pp.31-40
• /
• 2023

Given recent accidents involving autonomous vehicles, driver monitoring technology related to the transition of control in autonomous vehicles is gaining prominence. Driver status monitoring systems recognize the driver's level of alertness and identify possible impairments in the driving ability owing to conditions including drowsiness and distraction. In autonomous vehicles, predictive factors for the transition to manual driving should also be included. During traditional human driving, monitoring the driver's status is relatively straightforward owing to the consistency of crucial cues, such as the driver's location, head orientation, gaze direction, and hand placement. However, monitoring becomes more challenging during autonomous driving because of the absence of direct manual control and the driver's engagement in other activities, which may obscure the accurate assessment of the driver's readiness to intervene. Hence, safety-ensuring technology must be balanced with user experience in autonomous driving. We explore relevant global and domestic regulations, the new car assessment program, and related standards to extract requirements for driver status monitoring. This kind of monitoring can both enhance the autonomous driving performance and contribute to the overall safety of autonomous vehicles on the road.

• New & Renewable Energy
• /
• v.20 no.1
• /
• pp.102-109
• /
• 2024

The Typical Meteorological Year (TMY) dataset compiles 12 months of data that best represent long-term climate patterns, focusing on global horizontal irradiance and other weather-related variables. However, the irradiance measured on the plane of the array (POA) shows certain distinct distribution characteristics compared with the irradiance in the TMY dataset, and this may introduce some biases. Our research recalculated POA irradiance using both the Isotropic and DIRINT models, generating an updated dataset that was tailored to POA characteristics. Our analysis showed a 28% change in the selection of typical meteorological months, an 8% increase in average irradiance, and a 40% reduction in the range of irradiance values, thus indicating a significant shift in irradiance distribution patterns. This research aims to inform stakeholders about accurate use of TMY datasets in potential decision-making. These findings underscore the necessity of creating a typical dataset by using the time series of POA irradiance, which represents the orientation in which PV panels will be deployed.

• School Mathematics
• /
• v.9 no.2
• /
• pp.197-222
• /
• 2007

The study aims to reflect the elementary school geometry education based on the Realistic Mathematics Education in the Netherlands in the light of the results from recent researches in geometry education and the direction of geometry standards for school mathematics of the National Council of Teachers of Mathematics in order to induce implications for improving korean geometry curriculum and textbook series. In order to attain these purposes, the present paper reflects the history of elementary school geometry education in the Netherlands, sketches the elementary school geometry education based on the Realistic Mathematics Education in the Netherlands by reflecting general goals of the mathematics education, the core goals for geometry strand of the Netherlands, and geometry and spatial orientation strand of Dutch Pluspunt textbook series for the elementary school more concretely. Under these reflections on the documents, it is analyzed what is the characteristics of geometry strand in the Netherlands as follows: emphasis on realistic spatial phenomenon, intuitive and informal approach, progressive approach from intuitive activity to spatial reasoning, intertwinement of mathematics strands and other disciplines, emphasis on interaction of the students, cyclical repetition of experiencing phase, explaining phases, and connecting phase. Finally, discussing points for improving our elementary school geometry curriculum and textbook series development are described as follows: introducing spatial orientation and emphasizing spatial visualization and spatial reasoning with respect to the instruction contents, considering balancing between approach stressing on grasping space and approach stressing on logical structure of geometry, intuitive approach, and integrating mathematics strands and other disciplines with respect to the instruction method.

• Journal of the Korean Vacuum Society
• /
• v.19 no.4
• /
• pp.281-286
• /
• 2010

Thickness effects on the structural and optical properties of ZnO thin films fabricated by spin coating method have been carried out. With increase in the thickness of the ZnO thin films, the width and density of striation shape are increased. The ZnO thin film with thickness of 450 nm has a smooth surface morphology. For the ZnO thin film with a smooth surface, orientation factor ${\alpha}_{(002)}$ is sharply increased and FWHM of (002) diffraction peak is decreased compared to the ZnO thin films with a striation shape surface. Thickness and surface morphology of the ZnO thin films hardly affect the NBE peak position. However, the DLE peak position is blue-shifted as the surface morphology is changed from striation to smooth surface. The PL intensity ratio of the NBE to DLE is increased and the FWHM of NBE peak is decreased as the thickness of the ZnO thin films is increased.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.22 no.3
• /
• pp.127-133
• /
• 2012

To achieve low-cost and high-efficiency of thin-film solar cells applications, the sol-gel method that can be coated on a large area substrate, obtain homogeneous thin films of high purity was used. We studied structural and optical characteristics versus annealing temperature of $Cu_2ZnSnS_4$ which has kesterite structure by substitution low-cost sulfur (S) instead of high-cost selenium (Se). By analyzing XRD patterns, main peak was observed at $2{\theta}=28.5^{\circ}$ when Zn/Sn ratio is 0.8/1.2. And when we observed kesterite structure which has orientation of (112) direction, the more annealing temperature increase the bigger strength of (112) direction is. $Cu_2ZnSnS_4$ thin film showed characteristics of kesterite structure at $550^{\circ}C$. And when we calculated lattice constant, a = 5.5047 and $c=11.014{\AA}$ as same JCPDS (Joint Committee on Powder Standards) data measured. We measured optical transmittance to analyze optical characteristics. Optical transmittance was lower than 65 % at visible ray (${\lambda}=380{\sim}770nm$).

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.327.1-327.1
• /
• 2014

Nitrides-on-silicon structures are considered to be an excellent candidate for unique design architectures and creating devices for high-power applications. Therefore, a lot of effort has been concentrating on growing high-quality III-nitrides on Si substrates, mostly Si(111) and Si(001) substrates. However, there are several fundamental problems in the growth of nitride compound semiconductors on silicon. First, the large difference in lattice constants and thermal expansion coefficients will lead to misfit dislocation and stress in the epitaxial films. Second, the growth of polar compounds on a non-polar substrate can lead to antiphase domains or other defective structures. Even though the lattice mismatches are reached to 16.9 % to GaN and 19 % to AlN and a number of dislocations are originated, Si(111) has been selected as the substrate for the epitaxial growth of nitrides because it is always favored due to its three-fold symmetry at the surface, which gives a good rotational matching for the six-fold symmetry of the wurtzite structure of nitrides. Also, Si(001) has been used for the growth of nitrides due to a possible integration of nitride devices with silicon technology despite a four-fold symmetry and a surface reconstruction. Moreover, Si(110), one of surface orientations used in the silicon technology, begins to attract attention as a substrate for the epitaxial growth of nitrides due to an interesting interface structure. In this system, the close lattice match along the [-1100]AlN/[001]Si direction promotes the faster growth along a particular crystal orientation. However, there are insufficient until now on the studies for the growth of nitride compound semiconductors on Si(110) substrate from a microstructural point of view. In this work, the microstructural properties of nitride thin layers grown on Si(110) have been characterized using various TEM techniques. The main purpose of this study was to understand the atomic structure and the strain behavior of III-nitrides grown on Si(110) substrate by molecular beam epitaxy (MBE). Insight gained at the microscopic level regarding how thin layer grows at the interface is essential for the growth of high quality thin films for various applications.