• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.80-84
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• 1996

The effects of guide pads on burnishing action and accuracy of machined hole are investigated in drilling with burnishing drill using a speciaaly designed tool experimentally. The cutting forces are balanced at the small forward regions of guide pads. The burnishing action takes place under a high contact pressure between the bore wall and those regions. The over size mechanism of machined hole by the guide pads is discussed.

• 한국생산제조학회지
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• 제20권6호
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• pp.685-691
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• 2011

The Bearing preload units are used for stable rotational movements of high speed spindles. The feeding mechanism of the preload unit is important to prevent overheat of bearings and to keep constant bearing load under thermal deformation of spindle unit. In this study, ball slide guide and ball bush as feeding mechanism of preload unit are selected. The maximum static friction force, radial stiffness and damping ratio of ball slide guide with ball load, ball number and ball size are widely investigated. In conclusion, the surface of ball slide guide must be heat treated to reduce static friction force. The number and size of ball are increased to control sensitive bearing preload force.

• 설비공학논문집
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• 제20권4호
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• pp.238-244
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• 2008

This study investigates on the improvement of inhalation effect of hood which attached new device named as "gas-guide-device" in local exhaust ventilation system for the effective elimination of harmful material and dust in manufacturing factory. The gas-guide-device having a diamond shape is composed of width (b) and two sides of a device (X, Y) and its size is selected the industrial hood under application in manufacturing factory after due consideration. In order to investigate the effect of gas-guide-device, numerical and experimental study is performed that the flow velocity is calculated and is measured by a commercial program "COMSOL $Multiphysics^{TM}$" and a hot wire type of anemometer, respectively. The numerical and experimental results are revealed is a similar pattern and flow velocity has improved to hood attached gas-guide-device. Also, the numerical method and result is also verified the dependance. Moreover, the optimum shape and size of gas-guide-device is revealed that the width (b) and the ratio of two sides of gas-guide-device (X, Y) has 125mm and 4 to 6.

• Restorative Dentistry and Endodontics
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• 제49권2호
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• pp.21.1-21.8
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• 2024

Objectives: This paper aims to serve as a useful guide for sample size determination for various correlation analyses that are based on effect sizes and confidence interval width. Materials and Methods: Sample size determinations are calculated for Pearson's correlation, Spearman's rank correlation, and Kendall's Tau-b correlation. Examples of sample size statements and their justification are also included. Results: Using the same effect sizes, there are differences between the sample size determination of the 3 statistical tests. Based on an empirical calculation, a minimum sample size of 149 is usually adequate for performing both parametric and non-parametric correlation analysis to determine at least a moderate to an excellent degree of correlation with acceptable confidence interval width. Conclusions: Determining data assumption(s) is one of the challenges to offering a valid technique to estimate the required sample size for correlation analyses. Sample size tables are provided and these will help researchers to estimate a minimum sample size requirement based on correlation analyses.

• 한국주거학회논문집
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• 제17권1호
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• pp.145-153
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• 2006

Making of agreement with participation subjects is important process laying stress on presentation and a reasonable design guide line to form space order grant and synthetic space in Housing Complex plan. This study analyzed residing application specific character of design guide line that is presented to architects in general planning laying stress on plan only of 'Bongmu-dong town house' and design agreement of by architectural result that appear analyze. Result that analyze is as following: 1) Confer in 18 plan contents and integrate design or was adjusted. Being main conduct and unit plan and residing only in plan many negotiations accomplish. Architect who confer most Designs of 5 architects is 'Jean Michel Wilmott' and 'Shigeru Ban' 2) contents that confer much in plan main conduct and unit generation were details plan. Contents that is conferred with many architects are about door/core/rooftop be and asked a question about proper size of entrance. Negotiation about size was expose to the tribe of knowledge about element that do furniture and detail of necessary each space in life style of our country. We must present furnitures or detail element that appear by emotion of our country and detailed item of furnitures' size etc.. in guide line. It is immediate that creation of guide that architects can approach easily for lacking abroad architects of interests by code difference in each country is pressing. 3) In residing plan 4 architects of 5 architects applied similarly guide line in design. Most architects look by active support that make synthetic housing complex. and this is construed that act positively to make by unified residing. That plan of woods or landscape architecture and security of green area space are thing to approach on 'Environment-friendly mode of life residing only' that is general planning subject of 'Bongmu-dong town house'. 4) common question items of architects guide line of though is refered definitely when make out effective interests plan. So that can overcome legislation difference, countermeasure to make understood construction code of our country is pressing

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.69-77
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• 1999

The stabbing guide is often used to guide an add-on pile into an existing pile in offshore jacket installation. It provides a pile alignment for a welding tie-in in static condition as well. Even stabbing guide is an essential component in pile installation, it is not considered as a permanent offshore structure. In this regard, there is not a define design guideline proposed. In API RP 2A WSD, it briefly define the design considerations of stabbing guide. The failure of stabbing guide can cause a greate economical loss and a serious impact to the project schedule. Stabbing guide design should consider many factors considering actual work conditions for both static and dynamic situations. In the paper, a design method is proposed by appling the plate theory and it is confirmed numerically with FEM modeling. The geometry of stabbing guide is assumed as a cylinder shape with various wall thickness and effective length. The various thickness, effective length and pile size are compared for stable stabbing guide design.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 춘계 학술대회논문집
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• pp.208-213
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• 2004

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in- pool type, is under normal operation since it reached the initial critical in February 1995. The HANARO is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and is under developing a target handling tool for loading and unloading it in a circular flow tube (OR-5). A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube by jet flow. This paper is described an analytical analysis to calculate the hole size of a orifice inserted in the circular irradiation hole and to study the flow characteristics through the guide tube under reactor normal operation and loading the target. As results, the results show that the hole size of orifice was 31 mm of the inner diameter to suppress the guide tube jet flow and the coolant safely cooled the target of fission moly after inserting the orifice to the flow tube.

• 한국의류산업학회지
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• 제22권5호
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• pp.617-627
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• 2020

This study investigates the apparel sizing communication presented in online retail websites focusing on women's ready-to-wear tailored jackets and to analyze the meaning of these information as the actual product size guide factor. A total of 34 retail websites were selected based on the highest growth fashion companies list and the best fashion brands list. We collected size information in two types: size specifications including sizing code, body measurements, garment measurements, and size references including customized size guide tools, size information in customer reviews, model size information, and others. Most websites prefer to present garment measurements rather than body measurements that are recommended notations under Korean standards and related regulations. In addition, there was the absence of consistency in presenting measurements list and terms that can confuse consumers in size communication. This study found that the stature measurement was a key factor in size reference despite that it did not represent a proper garment size. The obsolete Korean numbering sizing code such as '55 and '66 was still used in many ways such as idiomatic expressions for body shape. It also implied that we can take advantage of the old sizing code for accessible size information. The finding of this study gives an in-depth diagnosis of current online sizing information problems and suggests useful basic data for developing online apparel size standards and marketing strategies.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.888-891
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• 2005

In this paper, the prototype of a walking guide robot with tactile display is introduced, and the psychophysical experiment of the tactile recognition for a tactile display is carried out and analyzed. The objective of this research is the development of a walking guide robot for the blind to walk safely. A walking guide robot consists of a guide vehicle and a tactile display device. A guide vehicle, located in the front of the walking blind, detects the obstacle using ultrasonic sensors and offers the information of position and walking direction acquired from GPS module to the walking blind by voice. The tactile display device, located in the handle which is connected with the guide vehicle by cane, offers the processed obstacle information such as position, size, moving, shape of obstacle and safe path, etc. The psychophysical experiments for the threshold of perception and recognition ability of tactile stimulation are carried out by the estimation of the subject group. As a result the appropriate tactile stimulus intensity and frequency to recognize tactile stimulation effectively are discussed and derived.

• 제어로봇시스템학회논문지
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• 제13권8호
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• pp.783-789
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• 2007

In this paper, firstly, we propose a generating method of the 3-D obstacle map using ultrasonic sensors. Secondly, we try to find the necessary stimulation conditions of compact tactile display device for effective transfer of obstacle information. The final goal of this research is the development of a walking guide system for the blind to walk safely. The walking guide system consists of a guide vehicle for the obstacle detection and a tactile display device for the transfer of the obstacle information. The guide vehicle, located in front of the walking blind, detects the obstacle using ultrasonic sensors. The processed information makes an obstacle map and transmits safe path and emergency situation to the blind by the tactile display. The tactile display device, located in the handle which is connected with the guide vehicle by cane, offers the processed obstacle information such as position, size, moving, shape of obstacle and safe path, etc. The concept of a walking guide system with tactile display is introduced, and experiments of 3-D obstacle detection and tactile perception are carried out and analyzed.