• Journal of Family Resource Management and Policy Review
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• v.8 no.1
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• pp.101-116
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• 2004

This study analyze using pattern of the Korean elderly leisure time to know their leisure lifestyle. In order to do this study, we analysed the time use dairy which were collected by Korean National Statistical Office in 1999 and analysis of data was done through mean of time, percentage of acting people hourly. The result of this study were as follows : 1) The elderly spend leisure time average 6 hours 34 minute in a day and enjoy leisure activities from A.M. 11:00 to P.M. 12:00 and from P.M. 8:00 to P.M:. 10:00 mainly. 2) The elderly spend leisure time for acquaintance, using mass media, sports leisure activity and dilettante life. Especially the elderly associate with more others than their family, use more TV than others and spend time for break and amusement as dilettante life.

• Korean Journal of Bronchoesophagology
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• v.13 no.2
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• pp.68-71
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• 2007

Fractured tracheostomy tube presenting as foreign body in the tracheobronchial tree is very rare. Authors experienced a case of broken tracheostomy tube presenting as a foreign body in the trachea, which was removed with the help of flexible bronchoscope. A few causes could be suggested for the tube break: aging and deterioration of the tube with repeated use, a flaw of the tube in the manufacturing process, and a wrong sterilization.method causing weakness of the tube. We report this case with brief literature review.

• ETRI Journal
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• v.32 no.2
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• pp.292-301
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• 2010

Increasing convergence among heterogeneous radio networks is expected to be a key feature of future ubiquitous services. The convergence of radio networks in combination with dynamic spectrum allocation (DSA) could be a beneficial means to solve the growing demand for radio spectrum. DSA might enhance the spectrum utilization of involved radio networks to comply with user requirements for high-quality multimedia services. This paper proposes a simple spectrum allocation algorithm and presents an analytical model of dynamic spectrum resource allocation between two networks using a 4-D Markov chain. We argue that there may exist a break-even point for choosing whether or not to adopt DSA in a system. We point out certain circumstances where DSA is not a viable alternative. We also discuss the performance of DSA against the degree of resource sharing using the proposed analytical model and simulations. The presented analytical model is not restricted to DSA, and can be applied to a general resource sharing study.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3203-3207
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• 2012

The nucleophilic substitution reactions of diisopropyl chlorothiophosphate (5) with X-pyridines have been kinetically studied in MeCN at $35.0^{\circ}C$. The Hammett and Br$\ddot{o}$nsted plots for the substituent X variations in the nucleophiles show biphasic concave upwards with a break point at X = 3-Ph. The pyridinolysis rate of 5 exhibits great negative deviation from the Taft plot. A concerted $S_N2$ mechanism is proposed involving a change of the attacking direction of the X-pyridines from a frontside attack with the strongly basic pyridines to a backside attack with the weakly basic pyridines.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.59-64
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• 2002

The photocatalytic decolorization of the Rhodamine B (RhB) was studied using a UV/TiO$_2$ reactor. Yakuri titanium dioxide(anatase) was used as the suspended photocatalyst and proved to be effective for decolorization irradiated with UV light (254 mm). The photocatalyzed dioxide concentrations, light intensity and air flow rates. In 0.01 mM RhB, color could be completely photodegraded after 3 hours. Absorption spectrum of an aqueous solution containing RhB showed a continued diminution of the RhB concentration in the solution bulk : concomitantly, no new absorption peaks appeared. This confirmed the decolorization of RhB, i.e., the break up of the chromopore. The optimum loaded titanium dioxide for the decolorization was 0.75 g/(equation omitted). The light intensity showed exponential decay with distance. The decay of light intensity of RhB solution showed different tendency from TiO$_2$. These results suggested that the photocatalytic decolorization of dyes may be available method for decolorizing in wastewater.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.251-254
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• 2003

To control the spread of surface fire in the rangelands and to check the entry of fire into forest systems from grassland patches, 26 evergreen / succulent species were selected and among them 3 shrubby species such as Berberis tintoria Lesch, Elaeagnus kologa Schlecht and Rhodomyrtus tomentosa Wt. were screened for vegetational fire breaks on the basis of leaf moisture content and some other ecological characters. The fire trail experiments indicate that crossing of fire was checked by the fire belt size of 5 ${\times}$ 1.5m for all the three species. However, due to higher fire retardant capacity, the Ire belt of R. tomentosa was effective in comparison to other two species.

• Speech Sciences
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• v.11 no.3
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• pp.181-192
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• 2004

The metrical structures in orally produced the poetry were generally analyzed by accent, metre and syllable. The purpose of this study is to investigate of metrical structures of Korean modem poetry using computer implemented speech analysis system. Two famous poet's poems confidential talk, Miloe and 'A buddhist dance, Sungmu' were selected for prosodic analysis. The informant is 60 years old professor in major of Korean and French poetry. The syllable structures of poems were analyzed primarily by vowel timbers, which can classified compact and diffuse vowels according to the distance of F2-F1. The perception cues of consonants were analyzed by VOT and tensity features of articulation. Rhythm is classified by dactyl, anapest, trochee, spondee and iambic. As a result, syllable structures of Korean modem poetry were mainly CV and CVC and the reading times of each lines were 3-4sec for 12 and 15 syllables. Main metre of Korean modem poems constructed the Imbic and Anapest. The break of each lines were demarcated by grammatical structure or meaning rather than phonetic structures.

• Explosives and Blasting
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• v.17 no.2
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• pp.19-35
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• 1999

Rock fragmentation with plasma blasting technique has advantageous properties in contrast to the conventional blasting method controlling of flying rocks and ground vibrations, when residents are complaining or surrounding structures stay in protection from blasting operations. The experiences show in urban construction works that the plasma blasting is the most possible method to prevent damages and minimize adverse environmental impacts. The fragmentation energy level is evaluated by numerical simulation using PFC for various drill hole patterns and tested accordingly to get the feasibility. The energy output of plasma blasting system has been improved to a level of 1 MJ, which can break a 2-3 ㎥ granite boulder or 1.5m height bench face. Measurements are carried out to get the ground vibration level and propagation equation, so that control of the blasting operations can be performed more precisely and safely.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.4
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• pp.57-66
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• 1985

This paper deals with an experimental study on a liquid atomization to investigate the break- up mechanism of a liquid film flow which is formed by a high speed air flow in parallel direction and an atomization characteristics of a liquid film flow in order to provide the basic data for the development of the twin fluid atomizer. Authors had built the simplified, transparent new devices which can form a uniform thickness of liquid film and an electrical measuring circuit of the liquid film thickness. By introducing the new devices and the measuring circuit, the time variation of a liquid film thickness the mean diameter of the droplets, the droplet size distribution, the degree of the dispersion and the atomization rate of a liquid film are measured experimentally. As the analysis of the study, it can be said the experimental investigation will fairly contribute for further study in this field of study.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.183-190
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• 1996

Leak-before-break(LBB) approach has been shown to be both cost and risk effective by reducing maintenance cost and occupational exposure when applied to high energy piping in nuclear power plants. For Korean Next Generation Reactor(KNGR) development, LBB is considered for the Main Steam Line(MSL) piping inside containment. Unlike the reactor coolant piping leakages which can be detected by particulate and gaseous radiation monitoring, main steam line leak detection systems must be based on principles that do not involve radioactivity. Ceramics are widely used as humidity sensor materials which can be further developed for nuclear applications. In this paper, we describe the progress in the development of ceramic humidity sensors for use with the main steam lines of KNGR.