• The Bulletin of The Korean Astronomical Society
• /
• v.46 no.2
• /
• pp.75.2-76
• /
• 2021

MESSIER is a science satellite project to observe the Low Surface Brightness (LSB) sky at UV and optical wavelengths. The wide-field, optical system of MESSIER is optimized minimizing optical aberrations through the use of a Linear Astigmatism Free - Three Mirror System (LAF-TMS) combined with freeform mirrors. One of the key factors in observations of the LSB is the shape and spatial variability of the Point Spread Function (PSF) produced by scatterings and diffraction effects within the optical system and beyond (baffle). To assess the various factors affecting the PSF in this design, we use PhoSim, the Photon simulator, which is a fast photon Monte Carlo code designed to include all these effects, and also atmospheric effects (for ground-based telescopes) and phenomena occurring inside of the sensor. PhoSim provides very realistic simulations results and is suitable for simulations of very weak signals. Before the application to the MESSIER optics system, PhoSim had not been validated for confocal off-axis reflective optics (LAF-TMS). As a verification study for the LAF-TMS design, we apply Phosim sequentially. First, we use a single parabolic mirror system and compare the PSF results of the central field with the results from Zemax, CODE V, and the theoretical Airy pattern. We then test a confocal off-axis Cassegrain system and check PhoSim through cross-validation with CODE V. At the same time, we describe the shapes of the freeform mirrors with XY and Zernike polynomials. Finally, we will analyze the LAF-TMS design for the MESSIER optical system.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.91-92
• /
• 2023

With the development of technology, interest in the implementation of free-form buildings is increasing, and research on producing free-form panels is being conducted accordingly. Since free-form buildings are curved and consist of geometric shapes, there are many problems with the production technology of free-form panels that implement them. Due to the inability to reuse molds, the cost of disposal of construction waste and waste of manpower for assembly increase the construction period and construction cost. To improve these limitations, a 3D printed concrete nozzle for FCP production was developed. However, this technology is not quantitatively extruded according to the shape of the panel, and there is a problem that residues are generated. Therefore, an free-form panel extrusion experiment was conducted to analyze the limitations of existing nozzles and to analyze the requirements for the development of new concrete extrusion nozzles. Existing nozzles were unable to be quantitatively extruded, resulting in errors. Due to the weak pressure of the screw and the inability to adjust the internal pressure, detailed extrusion speed control was impossible, and residue generation in the opening and closing device seemed to be the cause. Therefore, a pump capable of quantitative concrete pressure transfer and a pressure control device for easy extrusion of concrete are required. In addition, it is judged that it is necessary to develop an opening and closing device and an extrusion device that do not generate residues. The results of this study are expected to provide information for FCP production and production and to be a basic study of technologies necessary for the production of free-form building panels.

• Progress in Superconductivity and Cryogenics
• /
• v.25 no.4
• /
• pp.60-64
• /
• 2023

The manufacturing process of antibody drugs comprises two main stages: the upstream process for antibody cultivation and the downstream process for antibody extraction. The domestic bio industry has excellent technology for the upstream process. However, it relies on the technology of foreign countries to execute downstream process such as affinity chromatography. Furthermore, there are no domestic companies capable of producing the equipment for affinity chromatography. High gradient magnetic separation technology using a high temperature superconducting magnet as a novel antibody separation and purification technology is introduced to substitute for the traditional technology of affinity chromatography. A specially designed magnetic filter was equipped in the bore of the superconducting magnet enabling the continuous magnetic separation of nano-sized paramagnetic beads that can be used as affinity magnetic nano beads for antibodies. To optimize the magnetic filter that captures superparamagnetic nanoparticles effectively, various shapes and materials were examined for the magnetic filter. The result of magnetic separation experiments show that the maximum separation and recovery ratio of superparamagnetic nanoparticles are 99.2 %, and 99.07 %, respectively under magnetic field (3 T) and flow rate (600 litter/hr).

• Fashion & Textile Research Journal
• /
• v.25 no.5
• /
• pp.593-602
• /
• 2023

This study aimed to facilitate the use of virtual technologies such as sewing, appearance, and material expression in 3D virtual wear programs. For product production and education, we expounded how to express the shoulder shape and silhouette of sleeve-expanded power shoulder jackets. Two designs of sleeve-expanded power shoulder jackets were selected, and virtual jackets were produced using a virtual avatar based on the body dimensions of female subjects in their 20s. The essential purpose of a 3D virtual power shoulder jacket is to express the shoulder angle rise and shoulder width, which are much wider than the avatar's shoulder. Therefore, the virtual pad values were adjusted for the collision and rendering of each thickness. In addition, the position and angle of the virtual pads were controlled through simulation. Appearance similarity was evaluated using photographic data and the virtual jackets. For the set-in sleeve virtual power shoulder jacket, the wrinkle expressions of the torso and sleeve were rated as moderate, and material expression was slightly insufficient. The similarity of some ease and width items of the torso was tightly expressed, and the overall appearance, positions of lines, and details of jackets were rated high, especially at the neck and sleeve shapes. In the case of the kimono virtual power shoulder jacket, the expressions of the torso wrinkles and buttons were slightly lower; however, the overall similarity, basic lines, ease, shoulder and neck details, and material expression of the virtual jackets were highly evaluated.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.25 no.4
• /
• pp.147-161
• /
• 2023

This study used 3D anthropometric data from the 8th Size Korea to type and analyze whole body shapes of obese women in their 20s and 30s, and constructed dimensional data for human body items needed to create a 3D human body model for each type. The data analysis used data from 148 obese women in their 20s and 30s, and a total of 48 index values, drop values, and angle items were subjected to factor analysis and one-way variance analysis to categorize body types and verify significant differences by type. As a result of the factor analysis, 12 factors were extracted and divided into 4 body types. Type 1 is a 'standard type with a curved torso with balanced upper and lower body lengths', Type 2 is a 'bending forward type with a short, thick lower body, and an uncurved torso', Type 3 is a 'lean back type with a long and thin lower body and an H-shape torso', Type 4 is a 'sway back type with a long and thick lower body and abdominal obesity'. The representative body type of obese women in their 20s and 30s was identified as Type 1. The constructed body shape information will be used as basic data for future 3D human body modeling.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.19 no.3
• /
• pp.619-624
• /
• 2024

Scaling is one of the most basic dental gum treatments and involves removing tartar that has hardened on teeth. However, inexperienced and unprofessional removal of tartar may damage the gums, resulting in excessive bleeding or damage to the teeth. For this reason, scaling must be done delicately according to the gum structure of various people, and sufficient practice must be provided. Related departments at the university are conducting scaling exercises. However, from the perspective of students who have not had sufficient practice, selecting subjects and conducting practice is not easy, and practice subjects may also avoid participating in practice due to discomfort and anxiety. Accordingly, in this study, we designed and implemented a virtual reality practice system using VR to create a virtual patient rather than an actual subject and implement various gum shapes step by step to enable repetitive practice and various scaling experiences.

• Journal of the Korean Society of Safety
• /
• v.39 no.1
• /
• pp.55-61
• /
• 2024

In response to the COVID-19 pandemic, the logistics industry in Korea has rapidly been expanding, with offline demand concentrating on online platforms owing to the development of digital infrastructure. This has increased the workload of courier drivers considerably, along with labor intensity. A delivery driver died recently from overwork due to the continuous increase in delivery volume, which raises social concerns. Delivery drivers work long hours, (over 12 hours) and are greatly affected by weather conditions, such as snow, rain, heat waves, and cold waves. In addition, they lack a fixed workplace; perform atypical work handling workpieces of various sizes, weights, and shapes; and spend a large amount of time driving as part of their work. This work involves a high level of tension and requires attention and concentration. Despite the frequency of industrial accidents in the courier industry, studies on safety and health to quantitatively analyze and systematize the work of courier workers are very scarce. Therefore, to define the work process necessary for investigating the harmful factors in delivery service and the work analysis, this study conducted interviews and on-site surveys to analyze the unit work of the delivery service by targeting delivery workers. In other words, a framework of unit work for work analysis was presented to enable research and analysis by considering the aforementioned characteristics of the courier industry. The process was broadly divided into work, transport, storage, delay, and inspection. Work was divided into loading, sorting, unloading, and door subcategories, and transportation was divided into vehicle, cart, and walking subcategories as well as 10 small processes. Moreover, 22 unit works were again drawn by conducting field surveys and interviews. The risk of unit work derived from this study was ergonomically evaluated, and the ergonomic analysis revealed that uploading and transportation were the most dangerous. The results of this study could be used as basic data for preventing industrial accidents among courier workers, whose work has increased with the logistics volume and the development of the logistics industry.

• Archives of design research
• /
• v.18 no.4 s.62
• /
• pp.257-266
• /
• 2005

The purpose of this study is to investigate the psychological reaction to the image of the worship space in the church buildings and to quantify its contribution of the stimulation elements causing such reaction, and finally to suggest basic data for realizing emotional worship space of the church architecture. For this, 143 christians were surveyed to analyze the relationship between 23 emotional expressions extracted from the worship space and 32 images of the worship space. The combined data was described with the two dimensional dispersion using the quantification theory III. The analysis found out that 'simplicity-complexity' of the image consisted of the horizontal axis (the x-axis) and 'creativity' of the image the vertical axis(the y-axis). In addition, to extract the causal relationship between the value of emotional reaction and its stimulation elements quantitatively, the author indicated 4 emotional word groups such as simple, sublime for x-axis and typical creative for y-axis based on its similarity by the cluster analysis, The quantification theory I was also used with total value of equivalent emotional words as the standard variance and the emotional stimulation elements of the worship space as the independent variance. 9 specific examples of the emotional stimulation elements were selected including colors and shapes of the wall and the ceiling, shapes and finish of the floor materials, window shapes, and the use of the symbolic elements. Furthermore, 31 subcategories were also chosen to analyse their contribution on the emotional reaction. As a result, the color and finish of the wall found to be the most effective element on the subjects' emotional reaction, while the symbolic elements and the color of the wall found to be the least effective. It is estimated that the present study would be helpful to increase the emotional satisfaction of the users and to approach a spatial design through satisfying the types and purposes of the space.

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.3
• /
• pp.139-144
• /
• 2000

This study was conducted to obtain the basic information to increase the practical use of soil survey data through the subdividing of valley shapes with soil sequences due to different parent rocks, and to study the relationship between the valley shapes and parent rock. The various rocks such as sedimentary(gray shale and sand stone) and igneous rocks(granite, granite gneiss and andesite porphyry) which are the major parent rocks in Yeongnam area were investigated. The characteristics of valleys formed and the kinds of soils derived from different rocks were analysed by using aerial photographs and topographical maps scaled 1:5,000. The rill density in igneous rock area was as high as 40. But the rill bifurcation ratio of first order stream was higher in the sedimentary than the igneous rocks except granite area. The mean slope of valleys in igneous areas was about 8%, which was higher than that of the sedimentary areas. The variability of valley width in the complexly metamorphosed rock, such as granite gneiss, and andesite porphyry, was greater than in sedimentary and in granite rocks. Based on the variability of valley widths and valley slopes, it was possible to classify the valleys into two types. The "Uterus-shaped valleys" had wide variability of valley width and were located in the areas of granite gneiss and andesite porphry rocks. while the "Roots-shaped valleys" had narrow variability of valley width and were located in the sedimentary areas. "Uterus-shaped valleys" were typified by having land forms of mountain foot slopes and alluvial fans, and the soil drainage sequences also had complexities. So that, we concluded that the variability of valley width and valley slopes was associated with kinds of parent rocks and metamorphism which influences soil sequence and characteristics.

• Cartoon and Animation Studies
• /
• s.19
• /
• pp.161-181
• /
• 2010

Human beings experience the outside world through senses and have developed various ways of representation to preserve what they've experienced. The rapid progress of digital technology has opened a new era of representation technology, and furthermore, is functioning as a technology which offers new experiences. The sensory experiences through the sense of sight, which humans depend on more than 70% to perceive the outside world, have been becoming the center of representing the reality as the 3-D graphics technology has been growing, and developing by being grafted onto different areas of study. Various technologies to express the sense of reality, such as the technology to reinforce the virtual reality and to represent it in the reality, computer graphic, TUI technology, and five sensory technologies which apply humans' senses, are making advancement based on humans' visual features and sensory elements. In particular, the 3-D technology to display solidness provides not only representation but also new sensory experiences, and is emerging as the key technology to image contents. However, compared to the development of technology of 3-D graphics, there have been few basic studies on the principles of the sense of vision. Therefore, in this study, the principles and elements to sense videos will be examined. The sensory features of 3-D images to represent the sense of reality will be researched into, especially focusing on the experiential and physiological elements to sense 3-D structures, and the physical and psychological elements to sense shapes, which might be hopefully the basic study for producing 3-D contents.