• Macromolecular Research
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• 제9권4호
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• pp.220-227
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• 2001

The polymerization of 1,6-heptadiyne was carried out by molybdenum and tungsten-based transition metal catalysts. This polymerization by MoCl$\_$5/ alone proceeded well to give a quantitative yield of polymer. The effect of monomer to catalyst mole ratio (M/C), initial monomer concentration ([M]$\_$0/), and the polymerization temperature for the cyclopolymerization of 1,6-heptadiyne was studied and discussed. The polymerization solution exhibited red color even after 30 min of polymerization time. The resulting polymers were mostly brown powders and mostly insoluble in any organic solvents although the polymerization proceeded in homogeneous manner in some cases. The polymer structure was characterized by various instrumental methods to have the conjugated polymer backbone structure carrying cyclic recurring unit. The thermal and morphological properties of the resulting poly(1,6-heptadiyne) were also discussed.

• 한국기계가공학회지
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• 제13권5호
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• pp.76-81
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• 2014

The Engineering ceramics have some excellent properties as materials for modern mechanical and electrical components. It is, however, not easy to polish them efficiently because they are strong and hard. This study is carried out to obtain a mirror surface on engineering ceramics by surperfinishing with high efficiency. To achieve this, we conducted a series of polishing experiments using representative engineering ceramics, such as $Al_2O_3$, SiC, $Si_3N_4$ and $ZrO_2$, using diamond abrasive film from the perspective of oscillations peed, the rotational speed of the workpiece, contact roller hardness, contact pressure and feed rate. Furthermore, the polishing efficiency and characteristics for engineering ceramics are discussed on the basis of optimal polishing time and surface roughness. Our results confirmed that efficient superfinishing conditions and polishing characteristics of engineering ceramics can be determined.

• 대한가정학회지
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• 제37권10호
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• pp.81-90
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• 1999

This study investigated the present traditional Korean farmhouse based on a survey of 30 households from Oiam-Ri folk Village in Chung-Nam Province. This study was primarily concerned with the present housing; the size and plan of the house, lighting and heating, the finishing materials of anbang(the master's bedroom or ondol) and the kinds of fumiture. I was also interested in identifying the socio-demographic and physical variables that influenced the housing, both the ordinary farm households and the descendent of nobility households. Bibliographical studies, cultural approaches, field surveys with tape recordings, and questionnaires were used to collect the data. The results showed that the types of house plans were mixed from the southern region(one-line type) and middle region(courtyard type). The heating system and the fuel for the ondol anbang has changed entirely from wood burning system to oil boiler system. The finishing material of the anbang floor changed from traditional oil paper and straw mats to vinyl flooring. Traditional fumiture and small decor items are disappearing and are being replaced by modem items, but the descendents of the nobility household kept many traditional type of fumiture and small decor items.

• 한국실내디자인학회논문집
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• 제16권1호
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• pp.56-64
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• 2007

Community facilities in apartment complex have been developed through residents' needs for housing environmental amenities and social trend for 'Well-being' combined with marketing competition among construction companies. But community facilities and fitness centers which are in the initial stage of development are not well fit with residents' needs because the designers plan the community facilities without considering on residents' life-style and preference. This study investigates the present status of fitness center, and surveys the residents' preference for the proposed fitness center design. The result includes that fitness center users in apartment complex want a convenient and comfortable resting spaces similar level with those in fitness center of mixed-use residential building. A resting space provides opportunity that community members meet each other as well as they can rest after exercise. The result also shows that the fitness center users prefer wood floor and wall as interior finishing materials in exercising space and resting space, which users think, gives more comfortable and splendid feeling.

• Journal of Mechanical Science and Technology
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• 제18권6호
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• pp.972-978
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• 2004

Forward slip is an important parameter often used in rolling-speed control models for tandem hot strip rolling mills. In a hot strip mill, on-line measurement of strip speed is inherently very difficult. Therefore, for the set-up of the finishing mill, a forward slip model is used to calculate the strip speed from roll circumferential velocity at each mill stand. Due to its complexity, most previous researches have used semi-empirical methods in determining values for the forward slip. Although these investigations may be useful in process design and control, they do not have a theoretical basis. In the present study, a better forward slip model has been developed, which provides for a better set-up and more precise control of the mill. Factors such as neutral point, friction coefficient, width spread, shape of deformation zone in the roll bite are incorporated into the model. Implementation of the new forward slip model for the control of a 7-stand hot strip tandem rolling mill shows significant improvement in roll speed set-up accuracy.

• 한국실내디자인학회논문집
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• 제41호
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• pp.11-18
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• 2003

This study was carried out to find the cases of change in the Anglican Church including its rectory in Onsuri, Gangwha island, which was built in Korean traditional architecture style. The materials used for the study were published books, old photos taken before the change, drawings, and field survey. The result are as followings. 1) Painting concealed natural wooden grain should be removed as well as carpet on the wooden floor. The way of ceiling finishing is to be restored as traditional way. 2) Refer to the rectory, it needs to be restored totally, since it has been changed many times through partial renovation. It lacks unification of design in entire elevation, windows and door. The practical spaces such as indoor flush toilet and boiler room are desirable not to be revealed or designed in harmony with other spaces. 3) Stript flooring in the rectory are to be restored to frame flooring, room finishing including vinyl flooring, vinyl wall paper and moulding along the cornice to the traditional paper finish. Lattice patterns of windows and doors are recommended to be restored according to the traditional design.

• KIEAE Journal
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• 제7권1호
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• pp.95-100
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• 2007

In apartment houses, said to be similar to a typical housing form, every household share the walls and floors. Many problems inevitably accompany such as an arrangement, as noise and vibration are shared among households. When investigating the percentage of apartment resident's dissatisfaction with housing environments, discontent due to noise ranks the highest. Among many different kinds of noises, noise such as floor crashing sounds show the highest indication rate in the residents' comparison of discontent. Therefore, it is the practice of insulating against noises such as floor crashing sounds that improves the apartment house environments. The factors influencing the floor impact sound insulation include floor finishing materials, shock absorbing floors (slabs included), and ceiling structures. The ceilings of the apartment houses, currently built in Korea, are set up with lower parts of slabs and paper finishing, or with double floors for protecting against floor impact sounds in order to improve the sound insulating performance. The most common the method of ceiling structure construction consists of 'wood boarded frames +Gypsum boards + ceiling papers', which is called the wood boarded frame method. This study aimed to measures and evaluates floor impact sound insulation by which the ceiling space are widened according to suppression system is added in apartment house ceiling structure.

• 소성∙가공
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• 제25권4호
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• pp.235-241
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• 2016

Dimensional accuracy of hot coil is improved by precise control of thickness profiles, flatness, width and winding profile. Especially, precise width control is important because yield could be increased significantly. Precise width control can be improved by predicting the amount of width spread. The purpose of this study is to develop the advanced prediction model for width spread in hot finish rolling for controlling width precisely. FE-simulations were performed to investigate the effect of process variables on width spread such as reduction ratio, forward and backward tension and initial width at each stand. From the statistical analysis of simulated data, advanced model was developed based on the existing models for strip width spread. The experimental hot rolling trials showed that newly developed model provided fairly accurate predictions on the strip width spread during the whole hot finishing rolling process.

• 한국염색가공학회지
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• 제26권3호
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• pp.181-186
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• 2014

This paper surveys improvement characteristics in muscle fatigue with bio-activity material imbedded fabric. For this purpose, the subjects wear the garment which is covered by bio-activity materials all over every day during 2 weeks of experimental period. After 2 weeks period, VAS(Visual Analogue Scale) index evaluation regarding muscle fatigue and pain has been conducted in comparison between before wearing and after so that we can evaluate the effect on muscle fatigue improvement. The effectiveness survey for testing products consists of improvement on krunkle, muscle fatigue and exercise capacity. As a result, 100% of test subject group completes a questionnaire with positive answer as above normal in every question. In addition the preference of testing products is researched in wearing comfort, activity and convenience. And it is marked above normal by 100% of test subject group as well. Moreover any kind of unusual skin reaction has not been detected in safety evaluation. Therefore this testing products is being judged as a beneficent product for improvement on muscle fatigue without any skin irritation.

• 대한건축학회논문집:계획계
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• 제35권4호
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• pp.37-44
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• 2019

According to the statistical surveys and studies, insufficient maintenance in the use of existing buildings caused fire and collapse accidents. In this respect, I analyzed the data managed by the current building maintenance and inspection system to find out the actual state of safety management and proposed two significant results. First, regarding the state of the buildings, the safety management status of the small-sized ones, where 20 years or more passed after construction, is the worst and a priority improvement plan is required. Second, there are eight deeply concerning factors for the fire incidents and collapse accidents of buildings. In the order of high risk, these factors are structural strength (seismic design), exterior wall finishing material, basement floor, interior finishing materials, other evacuation facilities, corridors stairs entrances, rooftop, fire partition. We need to have more special designs and management plans regarding high-risk factors as a system to prevent accidents in the building.