• Wind and Structures
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• 제12권5호
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• pp.425-439
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• 2009

The expediency of revising universal rules for the combination of gravity and lateral actions of wind force-resisting steel structures recommended by the Standards EN 1990 and ASCE/SEI 7-05 is discussed. Extreme wind forces, gravity actions and their combinations for the limit state design of structures are considered. The effect of statistical uncertainties of extreme wind pressure and steel yield strength on the structural safety of beam-column joints of wind force-resisting multistory steel frames designed by the partial factor design (PFD) and the load and resistance factor design (LRFD) methods is demonstrated. The limit state criterion and the performance process of steel frame joints are presented and considered. Their long-term survival probability analysis is based on the unsophisticated method of transformed conditional probabilities. A numerical example illustrates some discrepancies in international design standards and the necessity to revise the rule of universal combinations of loads in wind and structural engineering.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제26권1호
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• pp.19-30
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• 2023

This study analyzes the tasks selected and implemented by pre-service mathematics teachers to support students' development of epistemic actions. Data was collected from 20 students who participated in a mathematics education curriculum theory course during one semester, and multiple data sources were used to gather information about the microteaching sessions. The study focused on the tasks selected and demonstrated during microteaching by pre-service teachers. The results suggest that providing students with a variety of learning opportunities that engage them in different combinations of abductive and deductive epistemic actions is important. The tasks selected by pre-service teachers primarily focused on understanding concepts, calculation, and reasoning. However, the use of engineering tools may present challenges as it requires students to engage in two epistemic actions simultaneously. The study's findings can inform the development of more effective approaches to mathematics education and can guide the development of teacher training programs.

• Journal of Information Processing Systems
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• 제8권3호
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• pp.409-420
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• 2012

The decision-making by agents in games is commonly based on reinforcement learning. To improve the quality of agents, it is necessary to solve the problems of the time and state space that are required for learning. Such problems can be solved by Macro-Actions, which are defined and executed by a sequence of primitive actions. In this line of research, the learning time is reduced by cutting down the number of policy decisions by agents. Macro-Actions were originally defined as combinations of the same primitive actions. Based on studies that showed the generation of Macro-Actions by learning, Macro-Actions are now thought to consist of diverse kinds of primitive actions. However an enormous amount of learning time and state space are required to generate Macro-Actions. To resolve these issues, we can apply insights from studies on the learning of tasks through Programming by Demonstration (PbD) to generate Macro-Actions that reduce the learning time and state space. In this paper, we propose a method to define and execute Macro-Actions. Macro-Actions are learned from a human subject via PbD and a policy is learned by reinforcement learning. In an experiment, the proposed method was applied to a car simulation to verify the scalability of the proposed method. Data was collected from the driving control of a human subject, and then the Macro-Actions that are required for running a car were generated. Furthermore, the policy that is necessary for driving on a track was learned. The acquisition of Macro-Actions by PbD reduced the driving time by about 16% compared to the case in which Macro-Actions were directly defined by a human subject. In addition, the learning time was also reduced by a faster convergence of the optimum policies.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1609-1618
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• 2016

is a service providing the story synopses that match user's query. This paper analyzes the user log of which is the answers to the queries to find stories from database, and shows the tendency distribution of user creation. Specially, we analyze a joint distribution of the genres and actions of stories to get better understanding of the tendencies that cannot be found in the analysis of independent distribution. Furthermore, we define a correlation factor between genre and action, and investigate what combinations of the genres and actions are highly, less, and negatively correlated. Finally, we investigate how the tendencies of characters are related to genres and actions, and propose a visualization method to show the tendencies.

• Steel and Composite Structures
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• 제28권3호
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• pp.363-380
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• 2018

This paper presented an integral design procedure for demountable bolted composite frames with semi-rigid joints. Moment-rotation relationships of beam-to-column joints were predicted with analytical models aiming to provide accurate and reliable analytical solutions. Among this, initial stiffness of beam-to-column joints was derived on the basis of Timoshenko's plate theory, and moment capacity was derived in accordance with Eurocodes. The predictions were validated with relevant test results prior to further applications. Frame analysis was conducted by using Abaqus software with material and geometrical nonlinearity considered. Variable lateral loads incorporating wind actions and earthquake actions in accordance with Australian Standards were adopted to evaluate the flexural behaviour of the composite frames. Strength and serviceability limit state criteria were utilized to verify configurations of designed models. A wide range of frames with the varied number of storeys and bays were thereafter programmed to ascertain bending moment envelopes under various load combinations. The analytical results suggest that the proposed approach is capable of predicting the moment-rotation performance of the semi-rigid joints reasonably well. Outcomes of the frame analysis indicate that the load combination with dead loads and live loads only leads to maximum sagging and hogging moment magnitudes in beams. As for lateral loads, wind actions are more crucial to dominate the design of the demountable composite frames than earthquake actions. No hogging moment reversal is expected in the composite beams given that the frames are designed properly. The proposed analysis procedure is demonstrated to be a simple and efficient method, which can be applied into engineering practice.

• Steel and Composite Structures
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• 제35권3호
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• pp.327-341
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• 2020

The use of high-strength steel and concrete in the construction industry has been gaining increasing attention over the past few decades. With it comes the need to utilise high-strength structural bolts to ensure the design load to be transferred safely through joint regions, where the space is limited due to the reduced structural dimensions. However, research on the behaviour of high-strength structural bolts under various loading combinations is still insufficient. Most of the current design specifications concerning high-strength structural bolts were established based on a very limited set of experimental results. Moreover, as experimental programs normally include limited design parameters for investigation, finite element analysis has become one of the effective methods to assist the understanding of the behaviour of structural components. An accurate and simple full-range stress-strain model for high-strength structural bolts under different loading combinations was therefore developed, where the effects of bolt fracture was included. The ultimate strength capacities of various structural bolts obtained from the present experimental program were compared with the existing design provisions. Furthermore, design recommendations concerning the pure shear and tension, as well as combined shear and tension resistance of Grade 10.9 high-strength structural bolts were provided.

• Biomolecules & Therapeutics
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• 제7권2호
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• pp.112-120
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• 1999

The protective actions of ambroxol, rutin, glutathione and harmaline on oxidative damages of various tissue components were compared. The mechanisms by which they prevent oxidative tissue damages were explored. Lipid peroxidation of liver microsomes induced by combinations of $Fe^{2+}$ and ascorbate or $Fe^{+3}$, ADP and NADPH was inhibited by $50\; \muM$ of rutin, ambroxol, harmaline and glutathione. Ambroxol ($100\; \muM$) inhibited the degradation of hyaluronic acid by $Fe^{2+}$, $H_2O$_2$ and ascorbate, and it was greater than that of harmaline, whereas hyaluronic acid degradation was not prevented by rutin and glutathione. The compounds used ($100\; \muM$) did not protect the degradation of cartilage collagen by xanthine and xanthine oxidase. Rutin, glutathione and harmaline decreased the degradation of IgG by xanthine and xanthine oxidate, while ambroxol did not attenuate degradation of IgG. Glutathione showed a scavenging action on $H_2O_2$. The compounds all showed scavenging actions on hydroxyl radical. Ambroxol and harmaline exhibited quenching effects en singlet oxygen. In conclusion, ambroxol, rutin, glutathione and harmaline may exert protective effects differently on tissue components against oxidative attack depend on kind of tissue component and free radical.

• Steel and Composite Structures
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• 제43권4호
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• pp.483-500
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• 2022

Cold-formed steel wall panels sheathed with gypsum plasterboard have shown superior thermal and structural performance in fire. Recent damage caused by fire events in Australia has increased the need for accurate fire resistance ratings of wall systems used in low- and mid-rise construction. Past fire research has mostly focused on light gauge steel framed (LSF) walls under uniform axial compression and LSF floors under pure bending. However, in reality, LSF wall studs may be subject to both compression and bending actions due to eccentric loading at the wall to-roof or wall-to-floor connections. In order to investigate the fire resistance of LSF walls under the effects of these loading eccentricities, four full-scale standard fire tests were conducted on 3 m × 3 m LSF wall specimens lined with two 16 mm gypsum plasterboards under different combinations of axial compression and lateral load ratios. The findings show that the loading eccentricity can adversely affect the fire resistance level of the LSF wall depending on the magnitude of the eccentricity, the resultant compressive stresses in the hot and cold flanges of the wall studs caused by combined loading and the temperatures of the hot and cold flanges of the studs. Structural fire designers should consider the effects of loading eccentricity in the design of LSF walls to eliminate their potential failures in fire.

• 비교문화연구
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• 제42권
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• pp.205-240
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• 2016

동물관련 관용어는 비유 상징코드로써 각 문화권에서 일찍부터 발달되어 왔다. "인재가 쓰이면 호랑이가 되고 재야에 버려지면 쥐가 될 뿐."이라고 역설한 동방삭(東方朔)의 동물조합 비유도 그러한 경우이다. 하지만 오늘날 중국에서 호랑이를 거물급 탐관오리로, 쥐를 작은 탐관오리로 비유하는 것에서도 알 수 있듯이, 그러한 상징성이 늘 고정불변인 것은 아니다. 이에 본고에서는 동물조합 상징성이 보이는 이러한 상대성 및 가변성에 주목하면서 한중일 ３국에서의 동물조합 상징성의 특징을 고찰해 보았다. 그리고 그 결과 다음의 3가지 사실을 알 수 있었다. 첫 번째로, 유사한 동물조합에 있어서 동물조합이 달라지는 변용과정에는 해당조합을 바라보는 관점의 차이가 문화권마다 존재함을 알 수 있었다. 가령, 한국에서는 말과 소의 두 동물을 조합하였을 때, 그 두 동물사이의 '다름'에 주목하는 경향이 있다. 하지만 중국과 일본에서는 말과 소의 '가치'의 차이를 비교하는 관점이 상대적으로 더 발달하였다. 두 번째로, 한국에 비해 중국과 일본에서는 두 동물의 외형적 행동적 특성을 의인화한 상징방식이 비교적 발달하였다. 특히 중국에서는 "개는 남자, 닭은 여자."처럼 동물의 종류가 남녀성별을 나타내거나 "갓 난 송아지 범 무서운 줄 모른다."처럼 특정연령대를 의인화 상징하는 방식이 상대적으로 더 발달하였다. 반면 일본에서는 한 종류의 동물을 암수 한 쌍으로 조합시켜 남녀성별을 상징하는 방식이 비교적 발달하였음을 알 수 있었다. 세 번째로, 중국과 일본에서는 동물신체 특성에 착안한 동물조합 상징이 한국에 비해 발달하였다. '용두사미'라는 중국 고사 성어에서의 용의 머리와 뱀의 꼬리의 조합이 그러하며, "용의 수염(역린)을 만지고 호랑이 꼬리를 밟는다."라는 일본 속담에서 보이는 신체부위 조합이 또한 그러하다. 이러한 동물신체 조합을 통한 상징방식은 중국에서 일찍이 발달하였으며, 그 영향은 용, 기린, 봉황처럼 여러 동물의 신체부위 조합에 의한 상상속의 동물 탄생으로 나타난다. 동물조합은 동아시아 문화를 이해하는 하나의 중요 키워드라 할 수 있다.

• Journal of Biosystems Engineering
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• 제7권2호
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• pp.72-85
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• 1983

Rice whitening is performed by basically two different whitening actions known as abrasive and frictional. The former adopted in the emery stone abrasive type whiteners and the latter in the jet-air friction type. Comparative milling yields and whitening efficiencies between the whitening system consisting of jet-air friction type whiteners only and the system consisting of both abrasive- and jet-air friction-types have not yet been rigorously defined. This study was to examine the effect of combined operations of abrasive- and jet-air friction-type rice whiteners on milling yields and whitening efficiencies. The small capacity commercial units of the abrasive- and friction-type whiteners were used for the experiments. The combinations of whitening treatments were: 1) Once in the abrasive type and then two to three times in the friction type, 2) twice in the abrasive and then two to three times in the friction type and 3) three to five times in friction type. In these tests, counter pressures for the friction type whiteners were established differently as required to get about the same degree of whitening at the end of predetermined numbers of the repeated operations. The speed of emery stone and the slot angle of the screen were also the factors varied in the abrasive type whitener. Sheukwang rice variety having 13.05% M.C. was used in the tests. The dependent variables were the milled- and head-rice recoveries and electricity consumption. The results of the study are summarized as follows: 1. It was found that in the whitening systems consisting of abrasive- and friction-type whiteners slot angle of the screen, the rotational speed of emery stone roller had significant effect on the milling yields and whitening efficiency. In general, the increase of the emery stone roller speed from 690 to 950 rpm presented a positive effect on milling yield, and one-pass abrasive milling combinations had higher milling yields than two-pass abrasive milling combinations. 2. It was apparent that if the slot angle of the screen and the speed of emery stone roller are modified and set at an optimum level, the combination whitening system consisting of abrasive- and friction-type whiteners is better than the pure frictional whitening system consisting of jet-air friction type in terms of milling yields and efficiencies. 3. In the rice whitening system consisting of abrasive- and jet-air friction-type whiteners, the best whitening performance was obtained when the slot angle of the screen and the rotational speed of emery stone roller were $45^{\circ}$ and 950rpm, respectively, for the one-pass abrasive milling combinations. However, for the two-pass abrasive mi11ing combinations, the best performance was obtained with $75^{\circ}$ of slot angle and 950 rpm of the emery stone roller speed. 4. As compared with pure frictional whitening systems, the combination systems produced more milled rice by 0.8-1.0% point and more head rice by 0.5-1.5% point, and consumed less electricity by 0.15-0.20 KwH per 100kg of milled rice when the abrasive whiteners were operated in the modified conditions as described in item 3 above. Further study is recommended to find out optimum operational and design conditions of abrasive type whiterners.