• Journal of Biosystems Engineering
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• v.15 no.2
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• pp.88-98
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• 1990

The purpose of this study was twofold : first, to reduce as much as possible the shaking moments of the crank-type transplanting mechanism of walking-type rice transplanters, and second, to evaluate whether or not a crank-type transplanting mechanism, if its shaking moment is reduced, can be used in riding-type transplanters for high speed transplanting operations. For these purposes, kinematic and force analyses of the currently available crank-type transplanting mechanisms were made and their results were compared with those observed by experimentation. The degree of shaking moment effect was also estimated Various efforts to minimize the shaking moments led to the development of a crank-type mechanism with a balancing gear, in which an eccentric balancing gear is combined into the driven link axis. Analysis of the developed mechanism showed that about 20% of the shaking energy can be reduced and about 40% of reduction in peak shaking moment can be obtained when comparing with those obtained without the balancing gear. It was concluded that crank-type transplanting mechanisms can be used for high speed operations with a forward speed of 0.9-1.2m/s if the balancing gear is additionally mounted. However, further considerations must be made to solve the space constraints in relation to the structural frame of riding type of rice transplanters.

• IE interfaces
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• v.15 no.1
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• pp.82-88
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• 2002

A study was conducted to develop user-centered kitchen furniture and workspace to reduce fatigue and to prevent housewives's disorders such as low back pain and musculoskeletal disorders from housekeeping activities. A questionnaire survey and interview were performed on 150 households those live in 32Pyung-type($105m^2$) apartment in Seoul vicinity. Also actual housekeeping activities for 24 hours were video-taped for further motion analysis. Results of the study revealed that housewives complained the inconvenience and small size of storage space, and worksurface height as the most important problems to be considered for redesign. And they responded, if feasible, sitting is preferred over standing while they are working. After adapting a sit/stand chair in the kitchen, a physiological experiment measuring heart rate(HR) and oxygen consumption($VO_2$) as response variables was conducted to examine the effects of sit/stand chair in reducing physiological demand during housekeeping activities. The results showed that working on sit/stand chair reduced energy expenditures by maximum of 30% and 31.0% in terms of HR and $VO_2$, respectively. Also rearrangement of kitchen structure based on motion analysis showed that walking distance during daily housekeeping activities can be reduced by 5.5% on the average. Hence, it is concluded that adapting a sit/stand chair in the kitchen could reduce fatigue and occupational disorders of housewives from extended housekeeping activities.

• The Journal of Korea Robotics Society
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• v.9 no.1
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• pp.57-66
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• 2014

This paper describes the design concept of a bio-inspired legged underwater and estimating its performance by implementing simulations. Especially the leg structure of an underwater organism, diving beetles, is fully adopted to our designing to employ its efficiency for swimming. To make it possible for the robot to both walk and swim, the transformable kinematic model according to applications of the leg is proposed. To aid in the robot development and estimate swimming performance of the robot in advance, an underwater simulator has been constructed and an approximated model based on the developing robot was set up in the simulation. Furthermore, previous work that we have done, the swimming locomotion produced by a swimming patten generator based on the control parameters, is briefly mentioned in the paper and adopted to the simulation for extensive studies such as path planning and control techniques. Through the results, we established the strategy of leg joints which make the robot swim in the three dimensional space to reach effective controls.

• Research in Mathematical Education
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• v.26 no.1
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• pp.1-17
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• 2023

Over the last three decades, there has been an increasingly strong emphasis on group-centered approaches to mathematics teaching. One primary responsibility for teachers who use group-centered instruction is to "check in", or intervene, with groups to monitor group learning and provide mathematical support when necessary. While prior research has contributed valuable insight for successful teacher interventions in mathematics group work, there is a need for more fine-grained analyses of interactions between teachers and students. In this study, we co-conducted research with an exemplary middle grade teacher (Ms. Green) to learn about fine-grained details of her intervention practices, hoping to generate knowledge about successful teacher interventions that can be expanded, replicated, and/or contradicted in other contexts. Analyzing Ms. Green's practices as an exemplary case, we found that she used exceptionally short interventions (35 seconds on average), provided space for student dialogue, and applied four distinct strategies to support groups to make mathematical progress: (1) observing/listening before speaking; (2) using a combination of social and analytic scaffolds; (3) redirecting students to task instructions; (4) abruptly walking away. These findings imply that successful interventions may be characterized by brevity, shared dialogue between the teacher and students, and distinct (and sometimes unnatural) teaching moves.

• Korean Institute of Interior Design Journal
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• v.23 no.6
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• pp.160-168
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• 2014

Five strongest crimes against women has rapidly increased recently, and women' anxiety is also increasing. Especially, women who reside alone in houses show significantly high anxiety. Such social change is increasing necessity of applying CPTED to housing environment of a single woman household. However, there have been less than enough number of researches on application on CPTED to housing environment of single woman household. So, this study would like to suggest housing environment of single woman household through CPTED guideline. With respect to research method, this study surveyed single woman households in their twenties and thirties who reside at single houses in Gwanak Gu, Gangnam Gu, Songpa Gu, and Mapo Gu in Seoul about necessity of CPTED guideline. Based on the survey results, this study conducted frequency analysis and descriptive statistics; and conducted independent sample t-test, one-way ANOVA, and Scheffe's posteriori test, according to demographic characteristics. As a result, differences in the contents of CPTED guideline by the demographic characteristics turned out to be small, generally. Thus, I concluded that suggestion for housing environment according to characteristics is not necessary. Instead, I would suggest contents of CPTED guideline that gained more than 4 points for housing environment. Research results of this study are as follow. First, 'Securing view of inside and outside of the house and controlling access' should be applied to housing environment of single woman households in their twenties and thirties residing in single houses in Seoul. Second, 'Securing view of an alley and improving walking space' should be applied. Third, 'installing CCTV and emergency bell' should be applied. Fourth, 'reinforcing territoriality of space' should be applied.

• Animal Bioscience
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• v.36 no.7
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• pp.1143-1149
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• 2023

Objective: We investigated the effects of outdoor access for 1 h per day on the animal welfare (AW) of tethered cows, in terms of lying and sleeping postures, and immune function. Methods: A total of five dry cows were tethered all day indoors (tethering) for 30 days and then tethered indoors with 1 h daily outdoor access (ODA-1h) for 30 days. To analyze the effects of ODA-1h, we calculated the total duration and bout frequency per day, and bout duration of lying and sleeping postures during the last five days of each treatment period. We also analyzed the populations of T cells, B cells, and NK cells in peripheral blood mononuclear cells (PBMC) by fluorescence-activated cell sorting and determined the concanavalin A (Con A) -induced proliferation rate of T cells. Results: The mean total time per day of lying during the ODA-1h treatment was significantly shorter than that during the tethering treatment (p<0.001). The Con A-induced proliferation rate of T cells during the ODA-1h treatment was significantly higher than that during the tethering treatment (p = 0.007). The proportion of NK cells in PBMC during the ODA-1h treatment tended to be higher than that during the tethering treatment (p = 0.062). Conclusion: Although ODA-1h may decrease lying time, it increases the available space for tethered cows towards that typically found in grazing and free barn feeding systems. This increased available space promotes the expression of normal behaviors such as walking and social behaviors except lying and may also improve the immune function of tethered dry cows, thereby improving their overall welfare.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.1
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• pp.55-75
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• 2017

The purpose of this study is to present the basic data for restoration of physical stream environment by analyzing habitat variables because habitat environment is changed due to the construction of waterfront space in urban streams. Assessment results of 10 habitat variables(three divisions) were almost same as optimal condition, in the reach of reference stream where there are no stream crossing structures and channel alteration. Assessment results of reaches in urban rivers, where streams were improved on water-friendly recreation activities, appeared to be marginal condition. Because habitat environment got worse due to stream improvement works such as construction of weir for water landscape, stepping stones for walking, low water revetment and high water revetment, and high water channel. In addition, in the case of mid gradient stream, the frequency of riffles was small or not existed because the intervals of the river crossing structures was short. In the case of mild stream types, the diversity of the pool was damaged due to the deposition of sludge in the upstream pool of weir and the installation of low water revetment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.262-265
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• 2006

In order to investigate characteristics of floor impact sound generated in the apartment buildings, questionnaire survey was conducted for respondents living in apartments in 200t. Questions in the surrey were on the characteristics of real impact sounds, subjective annoyance and satisfaction on the heavy and light impact sources. From the survey results, it was found that most annoying time of a day and the space were 8 p.m. to midnight at living room. It was also revealed that the main source of the floor impact sound from the upper floor is a child's jumping and running at from six to nine. More than half of people were not satisfied on the floor impact isolation performance of their own apartments. The percentage of residents who were annoyed by the heavy-weight impact sound such as children's jumping and adult's walking was $5{\sim}10%$ lower than by light-weight impact sound. In addition, females being responded more annoyed by floor impact sound than males.

• Korean Institute of Interior Design Journal
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• v.27 no.1
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• pp.12-20
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• 2018

After the "Landscaping Law" was enacted in 2007 Korea, national and local governments has been responding swiftly by seeking various methods. Seoul Metropolitan City and other municipalities have established "Seoul Coloring and Systematization" project, which analyzes and extracts the humanities, humanities and natural environments in 2007 as an opportunity to recognize the importance of environmental color. However, it is necessary to slightly supplement the color scheme created by the observer's concept. In this way, you have to find the color of the environment in a city where real life takes place. The city's environmental color has the concept of "walking" as the basic human behavior. Because the average speed is 4km, it differs from that of a vehicle that travels more than 60km per hour. Also, most of the frontage zone is used except for special cases. Therefore the characteristics of the environmental color and frontage zone on the road side were concluded in this paper as Single Type, Connection Type, and Extension Type. In addition, the principle of environmental color of city was established by the change of texture according to space of time and the characteristics of urban scale, and new media characteristics were found in various interactions. The results of this study suggest an environmental coloring strategy for workability such as hue continuity, hue harmonization and integrated design.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.913-920
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• 2000

The hall and the projection room of the multiplex cinema being constructed on the sixth and seventh floors at Jeonpo-dong market, Pusan, is composed of structural beams and decks considering the structures self weight problem, and the following problems are expected: - Vibration and noise generated on the floors by moving audiences may annoy the audiences in the other hall - Vibration and noise generate on the floor of the nearby hall as the audiences walk through the alley near the projection room - Vibration and noise generate on the floor of the hall nearby the projection room as the film drops This study measured and reviewed the vibration amount of the seven representative transferring routes that were selected for the halls and the alley near the projection room. Based on the analysis, the model hall was constructed and the vibration in the hall was estimated after cutting the deck. Also, this study constructed the steel stairs and investigated the vibration transferring characteristics to decide whether to construct the steel stairs in the building. Finally, the results were evaluated by actually using the stairs and reviewed the appropriateness of the measurement.