• Structural Engineering and Mechanics
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• v.20 no.3
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• pp.363-380
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• 2005

The cable tension plays an important role in the construction, assessment and long-term health monitoring of cable structures. The cable vibration equation is nonlinear if cable sag and bending stiffness are included. The engineering implementation of a vibration-based cable tension evaluation is mostly carried out by the simple taut string theory. However, the simple theory may cause unacceptable errors in many applications since the cable sag and bending stiffness are ignored. From the practical point of view, it is necessary to have empirical formulas if they are simple and yet accurate. Based on the solutions by means of energy method and fitting the exact solutions of cable vibration equations where the cable sag and bending stiffness are respectively taken into account, the empirical formulas are proposed in the paper to estimate cable tension based on the cable fundamental frequency only. The applicability of the proposed formulas is verified by comparing the results with those reported in the literatures and with the experimental results carried out on the stay cables in the laboratory. The proposed formulas are straightforward and they are convenient for practical engineers to fast estimate the cable tension by the cable fundamental frequency.

• Journal of the Korean housing association
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• v.26 no.6
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• pp.61-69
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• 2015

Current criticism regarding the "uniformity" of Korean apartments has shown not only tendencies of emotional and unscholarly criticism, but also lack of academic discourse. They tend to stay at the common-sense level and be quite subjective without supporting facts. This research began with questioning the phenomenon of seeing Korean apartments as an object of negative criticism. The research questions for this study are: 1. Of the living space of so-called apartment houses, what elements should be called uniform?; 2. How should the implications of the findings be interpreted? In this context, this study aims to reinterpret criticisms on the uniformity of apartments from a new point of view. First, literature review is done to examine characteristics of Korean apartments in the social-cultural, economic, and physical contexts. Next, existing non-academic, abstract criticisms are classified into three trends, to show that the way of understanding architectural spaces by those criticisms are limited and weighted towards visual perceptions focused only on the shape of architectural structures. Finally, it is argued that the viewpoints of space and residents' experience should be treated as important for the reinterpretation of criticisms on the uniformity. This is validated through presenting relevant cases such as changes of space uses, diversified lifestyles being accepted, and the expansion of living space.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.2
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• pp.109-116
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• 2010

The purpose of this study is to clarify the actual condition of the daily living activities of the elderly with dementia in nursing homes. The thorough investigation and observation works were made from the view points of daily living behaviors and behavioral places of the recuperating elderly with dementia in nursing homes. This article discusses about the basic characteristics of the elderly and the actual condition of the daily living activities of the elderly with dementia in 3 nursing homes. The results of this study are summarized as follows; There is no wide difference between skilled nursing facilities on the characteristic of living behaviors of the elderly with dementia. Daily living activities and the use of spaces are largely influenced by the daily program and the operation policy of each nursing homes in addition to human relationship of the elderly with dementia. Common spaces such as day room, dining room plays an important role for their daily living activities, because that most of the elderly with dementia stay long during daytime. Layout of each private room and common space seems very crucial point in designing these facilities, in order to enable demented people to live their lives more independently.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.12A
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• pp.1303-1310
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• 2007

In IEEE 802.11b wireless network, stations synchronize themselves to the beacons periodically sent by the access point (AP) when they are running in low power mode. Stations stay awake for enough time to receive beacon because it is delayed in AP if the wireless channel has been being used by other traffic at each scheduled instant. In this paper, we propose a method that measures the delay of received beacons and calculates wake-up interval of station to receive the next one. Beacon transmission delay at the AP is analyzed. The proposed method is simulated and its characteristics are described in the analysis. The result measured in terms of station's wake-up interval shows some enhancement in energy consumption.

• Journal of the Korean Ceramic Society
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• v.26 no.4
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• pp.559-567
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• 1989

Bioglasses have been known to be as one of the promising biomateials, which can be used for replacing defective hard and soft tissue. There have been many reports on biological results for this type of glass, but no systematic work has carried out on the structures and properties of the bioglass itself. In the present study, the effect of P2O5 in bioglasses on their structures and properties was examined. Infrared and Raman spectroscopy for the glass structural analysis, differential thermal and X-ray diffraction analysis for the crystallization of the bioglass were performed, and several physical properties were measured. When the glasses were heat-treated, Na2O.2CaO.3SiO2 was the major crystalline phase and $\beta$-NaCaPO4 crystal was found for the glass with high P2O5 content. The added P2O5 in the glasses enhanced the polymerization of silicate glass structure and it changed the chain-like glass structure to a sheet-like structure, and some P2O5 may stay as phosphate monomer. With addition of P2O5 in the glass the density of the glasses decreased, but not much changes in their thermal expansion coefficient, softening point and microhardness were observed.

• Korean Journal of Bronchoesophagology
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• v.4 no.2
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• pp.171-176
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• 1998

Postoperative pain following tonsillectomy remains a significant obstacle to speedy recovery and smooth convalescence. Inadequate analgesia causes poor oral intake and influences the length of hospital stay and ability to return to normal activity. Patient Controlled Analgesia (PCA) is a method of analgesia adminstration that consists of a computer driven pump with a button that the patient may press to adminster a small dose of analgesic drug. The aim of this study was to examine whether Intravenous Patient Controlled Analgesia (IV-PCA) can reduce postoperative pain after tonsillectomy. The 100 patients undergoing tonsillectomy with general anesthesia were divided into two groups. The PCA group patients (n=80) received a mixture of nalbuphine and ketorolac by Walkmed PCA infusor during first 48 postoperative hours. In control group (n=20), the patients received oral acetoaminophen (Tyrenol) regularly and tiaprofenic acid (Surgam) intramuscularly on a p.r.n basis. Analgesic efficacy was evaluated with visual linear analogue scale (VAS) and the adverse effects were evaluated with 4 point scale. The patients of PCA group had less pain than those of control group. The adverse effects in the PCA group were nausea and vomiting. This study suggests that IV-PCA may be safe and effective method of pain control after adult tonsillectomy and is better accepted than oral or intramuscular pain medications.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.1
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• pp.93-100
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• 2008

The purpose of this study is to clarify the actual condition of the daily living activities of the elderly with dementia in skilled nursing facilities. The thorough investigation and observation works were made from the view points of daily living behaviors and behavioral places of the recuperating elderly with dementia. This article discusses about the basic characteristics of the elderly and the actual condition of the daily living activities of the elderly with dementia in 2 skilled nursing facilities. The results of this study are summarized as follows; There is no wide difference between skilled nursing facilities on the characteristic of living behaviors of the elderly with dementia. Daily living activities and the use of spaces are largely influenced by the daily program and the operation policy of each skilled nursing facilities in addition to human relationship of the elderly with dementia. Common spaces such as day room, dining room plays an important role for their daily living activities, because that most of the elderly with dementia stay long during daytime. Layout of each private room and common space seems very crucial point in designing these facilities, in order to enable demented people to live their lives more independently.

• Korean Journal of Head & Neck Oncology
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• v.21 no.1
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• pp.10-14
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• 2005

Objectives: Various techniques of endoscopic thyroidectomy have been developed in thyroid resection since 1998 in the aspect of excellent cosmetic viewpoint. Of them, we evaluated our experiences and advantages of gasless axillary approach technique for resection of dominant thyroid nodules. Material and Methods: Twenty-nine cases of thyroid nodules were operated by the technique of gasless axillary approach during one year from December 2003 to December 2004. Twenty four patients underwent total lobectomy and five patients were partial lobectomy. Results: The operation time of first case took 300 minutes, however it became gradually shortened with case experiences down to 100-120 minutes. Pathologically, nodular hyperplasia was twenty cases, follicular adenoma five cases, papillary carcinoma three patients, and Hashimoto's thyroiditis one patient. There was no case of conversion to open thyroidectomy. Three cases of postoperative hoarseness were recovered spontaneously in 3 months. Hospital stay was four days for most patients. The cosmetic result was excellent without visible scar in anterior neck and chest. Conclusion: Endoscopic thyroidectomy via gasless axillary approach shows excellent result in cosmetic view point with hidden incision scar at axilla, and shorter hospitalization. However a question of longer operation time for dissection of the long plane over pectoral muscle is still remained.

• Korean Journal of Remote Sensing
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• v.19 no.3
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• pp.181-190
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• 2003

Since the operation of the first satellite-based navigation service, satellite positioning has played an increasing role in both surveying and geodesy, and has become an indispensable tool for precise relative positioning. However, in some situations, e.g. at a low angle of elevation, the use of satellites for navigation is seriously restricted because obstacles like buildings and mountains can block signals. As a mean to resolve this problem, the quasi-zenith satellite system has been proposed as a next-generation satellite navigation system. Quasi-zenith satellite is a system which simultaneously deploys several satellites in a quasi-zenith geostationary orbit so that one of the satellites always stay close to the zenith if viewed from a specific point on the ground of East Asia. Thus, if a position measurement function compatible with CPS is installed in the quasi-zenith and stationary satellites, and these satellites are utilized together with the CPS, four satellites can be accessed simultaneously nearly all day long and a substantial improvement in position measurement, especially in metropolitan areas, can be achieved. The purpose of this paper is to evaluate the effectiveness of quasi-zenith satellite system on positioning accuracy improvement through simulation by using precise orbital information of the satellites and a three-dimensional digital map. Through this developed simulation system, it is possible to calculate the number of simultaneously visible satellites and available area for positioning without the need of actual observation. Furthermore, this system can calculate the Dilution Of Precision (DOP) and the error distribution.

• Journal of Korean Philosophical Society
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• v.123
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• pp.135-164
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• 2012

This paper aims to clarify Heidegger's concept of 'play(Spiel)'. Through Heidegger's ideas of play, we are going to present that the concept of play, as frequently argued, not only stay with playful side associated with human mental activity but also like with further perspectives. In other words, we will show the ontological meaning of the Heidegger' concept of play. First, in Heidegger's early thinking, the play appears in 'play of life' or 'play of transcendence'. In contrast, in his later thinking, the play appears in 'play-space', 'Time-play-space', 'mirror-play', 'play of silent', etc. Thus, we have tried to clarify the Heidegger's concept of play that divided as the starting point of his turn(Kehre).