• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.38.1-38.1
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• 2020

Recent integral field spectroscopy observations have found that about 11% of galaxies show star-gas misalignment. The misalignment possibly results from external effects such as gas accretion, interaction with other objects, and other environmental effects, hence providing clues to these effects. We explore the properties of misaligned galaxies using Horizon-AGN, a large-volume cosmological simulation, and compare the result with the result of the Sydney-AAO Multi-object integral field spectrograph (SAMI) Galaxy Survey. Horizon-AGN can match the overall misalignment fraction and reproduces the distribution of misalignment angles found by observations surprisingly closely. The misalignment fraction is found to be highly correlated with galaxy morphology both in observations and in the simulation: early-type galaxies are substantially more frequently misaligned than late-type galaxies. The gas fraction is another important factor associated with misalignment in the sense that misalignment increases with decreasing gas fraction. However, there is a significant discrepancy between the SAMI and Horizon-AGN data in the misalignment fraction for the galaxies in dense (cluster) environments. We discuss possible origins of misalignment and disagreement. This presentation is mainly based on the published work Khim et al. 2020, ApJ, 894, 106 (17pp).

• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.58-70
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• 2017

The planning for material lifting operations is one of the key processes in high-rise building construction. Several previous studies have used rough calculations by referring to existing practices or establishing a target value for lifting cycle time or operating rate. Therefore, the purpose of this study is to propose a material lifting process optimization method for reducing the lifting cycle time and increasing the operating rate. In this study, we improve the cyclic operation network (CYCLONE) modeling method that considers the duration and zone information of each work task. This method can be used to hand over work tasks to another crew group in the work process. According to this methodology, this study optimizes the material lifting process, performs a sensitivity analysis, and evaluates the field applicability of the proposed material lifting process optimization method. Therefore, the optimized process was then applied to a high-rise building construction site. The lifting work process time and operating rate for the simulated as - is lifting process data, optimized process data, and field application result data were compared for each lifting height. From this comparison, the effectiveness of the optimization methodology was confirmed.

• Journal of the Korean Home Economics Association
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• v.32 no.1
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• pp.199-210
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• 1994

My purpose in the paper is to research on what is the most productive education method for the Students for Future Dietitian(SFD) to be applied during there field training & practice. Furthermore it is an attempt to elucidate what is the most necessary education program for the field training & practice for SFDs. Five questionnaires were given to SFDs dealing with nutrition purchase hygienic facilities and official management in order to check and evaluate the current situation and problems on the education of field training & practice for SFDs Also I chose 140 SFD's who had been working in the field for at least one week or one month in 1992 and statistical processing were utilized and analyzed by SAS package. One of the most notable problems SDFs faced with during meal planning it is the fact that they had been educated and requested for the cut of food expenditure rather than the supply of scientifically balanced-nutrition meals for working people, SFDs also faced with of information on the quantity and facilities management from the dietitian in the company. my research revealed that dietitian's teaching method for SFDs still remains in a very primitive way and accordingly the efficient way to solve these problems shall be established by a computerized education program through which dietitians can provide well-balanced meals for working people when they are assigned to the company. In this regard we must consider that we have to enact certain law to be applied to a dietitian. In another words we should emphasize actual experiences of SFDs' knowledge accumulated through the field training & practice before they work at the company. Consequently it is a time to reconsider the importance of well-balance dietitian program offering an opportunity for SFD which can contribute to improvement of health's condition for the working people.

• Journal of The Korean Astronomical Society
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• v.36 no.spc1
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• pp.75-81
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• 2003

Changes in the earth's climate depend on changes in the net sunlight reaching us. The net depends on the sun's output and earth's reflectance, or albedo. Here we develop the limits on the changes in the sun's output in historical times based on the physics of the origin of solar cycle changes. Many have suggested that the sun's output could have been $0.5\%$ less during the Maunder minimum, whereas the variation over the solar cycle is only about $0.1\%$. The frequencies of solar oscillations (f- and p-modes) evolve through the solar cycle, and provide the most exact measure of the cycle-dependent changes in the sun. But precisely what are they probing? The changes in the sun's output, structure and oscillation frequencies are driven by some combination of changes in the magnetic field, thermal structure and velocity field. It has been unclear what is the precise combination of the three. One way or another, this thorny issue rests on an understanding of the response of the solar structure to increased magnetic field, but this is complicated. Thus, we do not understand the origin of the sun's irradiance increase with increasing magnetic activity. Until recently, it seemed that an unphysically large magnetic field change was required to account for the frequency evolution during the cycle. However, the problem seems to have been solved (Dziembowski, Goode & Schou 2001) using f-mode data on size variations of the sun. From this and the work of Dziembowski & Goode (2003), we suggest that in historical times the sun couldn't be much dimmer than it is at activity minimum.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.283-293
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• 2015

The effect of the inlet swirling flow in a hydraulic turbine draft tube is a very complex phenomenon, which has been extensively investigated both theoretically and experimentally. In fact, the finding of the optimal flow distribution at the draft tube inlet in order to get the best performance has remained a challenge. Thus, attempting to answer this question, it was assumed that through an automatic optimization process a Genetic Algorithm would be able to manage a parameterized inlet velocity profile in order to achieve the best flow field for a particular draft tube. As a result of the optimization process, it was possible to obtain different draft-tube flow structures generated by the automatic manipulation of parameterized inlet velocity profiles. Thus, this work develops a qualitative and quantitative analysis of these new draft tube flow field structures provoked by the redesigned inlet velocity profiles. The comparisons among the different flow fields obtained clearly illustrate the importance of the flow uniformity at the end of the conduit. Another important aspect has been the elimination of the re-circulating flow area which used to promote an adverse pressure gradient in the cone, deteriorating the pressure recovery effect. Thanks to the evolutionary optimization strategy, it has been possible to demonstrate that the optimized inlet velocity profile can suppress or mitigate, at least numerically, the undesirable draft tube flow characteristics. Finally, since there is only a single swirl number for which the objective function has been minimized, the energy loss factor might be slightly affected by the flow rate if the same relation of the axial-tangential velocity components is maintained, which makes it possible to scale the inlet velocity field to different operating points.

• Journal of the Korean Society for information Management
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• v.37 no.2
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• pp.197-223
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• 2020

The purpose of this study is to analyze the issues resulted from the process of grouping KORMARC records using FRBR WORK concept and to suggest a new method. The previous studies did not sufficiently address the criteria or processes for identifying representative authors of records and their derivatives. Therefore, our study focused on devising a method of identifying the representative author when there are multiple contributors in a work. The study developed a method of identifying representative authors using an author role dictionary constructed by extracting role-terms from the statement of responsibility field (245). We also designed another way to group records as a work by calculating similarity measures of authors and titles. The accuracy rate of WORK grouping was the highest when blank spaces, parentheses, and controling processes were removed from titles and the measured similarity rates of authors and titles were higher than 80 percent. This was an experiment study where we developed an author-role dictionary that can be utilized in selecting a representative author and measured the similarity rate of authors and titles in order to achieve effective WORK grouping of KORMARC records. The future study will attempt to devise a way to improve the similarity measure of titles, incorporate FRBR Group 1 entities such as expression, manifestation and item data into the algorithm, and a method of improving the algorithm by utilizing other forms of MARC data that are widely used in Korea.

• Journal of Arbitration Studies
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• v.32 no.1
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• pp.25-42
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• 2022

The modern arbitration practice recognises the need for a faster and simplified procedural framework for international disputes with fairly low amounts at stake. This has driven several institutions to expand their offer of procedural guidelines with a simplified set of rules that would fit this purpose. Expedited arbitration is increasingly used by parties and is growing in popularity. The basic idea behind establishing expedited arbitration rules is to create the possibility for the parties to a dispute to agree on a simplified and streamlined procedure and to have an arbitration award issued within a short period. The associated cost savings for the parties is another benefit. The importance of developing rules for expedited dispute resolution has recently also been considered by the UNCITRAL Working Group II, in light of the "increasing demand to resolve simple, low-value cases by arbitration" and "the lack of international mechanisms cope with such disputes." As a result, the UNCITRAL 2021 Expedited Arbitration Rules (UNCITRAL EAR) took effect on September 19, 2021. The EAR was adopted by the Commission on 21 July 2021 and, next to UNCITRAL's well-known instruments like the Arbitration Rules (UAR) and the Model Law, represent another chapter in the Commission's impactful work in the field of international arbitration. Overall, the UNCITRAL EAR has great potential to meet the need for more flexible and efficient arbitration proceedings, primarily because they provide the tribunal with strong managerial powers while still leaving room for consultation with the parties. However, parties must remember that not all disputes may be suitable for expedited arbitration, and disputes that are complex or have the possibility of being joint or consolidated may not benefit from simplified procedures and tight deadlines. This article will outline the core features and characteristics of the UNCITRAL EAR.

• Smart Structures and Systems
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• v.16 no.5
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• pp.835-851
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• 2015

This paper presents theoretical and experimental evaluation of the structural health monitoring (SHM) capability of piezoelectric wafer active sensors (PWAS) at elevated temperatures. This is important because the technologies for structural sensing and monitoring need to account for the thermal effect and compensate for it. Permanently installed PWAS transducers have been One of the extensively employed sensor technologies for in-situ continuous SHM. In this paper, the electro-mechanical impedance spectroscopy (EMIS) method has been utilized as a dynamic descriptor of PWAS behavior and as a high frequency standing wave local modal technique. Another SHM technology utilizes PWAS as far-field transient transducers to excite and detect guided waves propagating through the structure. This paper first presents how the EMIS method is used to qualify and quantify circular PWAS resonators in an increasing temperature environment up to 230 deg C. The piezoelectric material degradation with temperature was investigated and trends of variation with temperature were deduced from experimental measurements. These effects were introduced in a wave propagation simulation software called Wave Form Revealer (WFR). The thermal effects on the substrate material were also considered. Thus, the changes in the propagating guided wave signal at various temperatures could be simulated. The paper ends with summary and conclusions followed by suggestions for further work.

• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.9-12
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• 1999

This paper presents the development of a control architecture for the autonomous underwater vehicle (AUV) with VARIVEC (variable vector) propeller. Moreover this paper also describes the new technique of controlling the servomotors using the Field Programmable Gate Array (FPGA). The AUVs are being currently used fur various work assignments. For the daily measuring task, conventional AUV are too large and too heavy. A small AUV will be necessary for efficient exploration and investigation of a wide range of a sea. AUVs are in the phase of research and development at present and there are still many problems to be solved such as power resources and underwater data transmission. Further, another important task is to make them smaller and lighter for excellent maneuverability and low power. Our goal is to develop a compact and light AUV having the intelligent capabilities. We employed the VARIVEC propeller system utilizing the radio control helicopter elements, which are swash plate and DC servomotors. The VARIVEC propeller can generate six components including thrust, lateral force and moment by changing periodically the blade angle of the propeller during one revolution. It is possible to reduce the number of propellers, mechanism and hence power sources. Our control tests were carried out in an anechoic tank which suppress the reflecting effects of the wall surface. We tested the developed AUV with required performance. Experimental results indicate the effectiveness of our approach. Control of VARIVEC propeller was realized without any difficulty.

• Journal of the Korea Furniture Society
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• v.25 no.3
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• pp.173-181
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• 2014

Since the onset of the 21st century, digital technology has been widely adopted in various fields of art; it has enabled artists or designers to try diverse and brand-new ways of expression in literally every possible field of art, including painting, sculpture, and other design work. Furniture design is no exception. From the initial design step to the final production of furniture, modern digital skills are broadly utilized, creating a whole new set of designs that would otherwise be hardly conceivable and realizing a highly efficient furniture-making mechanism. More recently, the 3D printing technique, which is called a 21st century alchemy, has been successfully commercialized and is getting more popular, heralding yet another innovative shift in the area of furniture design and production. In this context, this study discusses the background of the furniture design using digital technology, and identifies the correlations between the modern digital technology and furniture design by redefining the concept of such digital technology. By reviewing multiple real-life cases, some of the key digital expressions found in modern furniture design are also analyzed. This study aims at suggesting the reason why digital technology is significant and promising in diverse ways for the development of modern furniture design.