• The Journal of the Korean dental association
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• v.53 no.11
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• pp.789-794
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• 2015

Swallowing disorders or dysphagia, which are difficulties with the act of swallowing, can occur at different phases such as oral, pharyngeal, and esophageal phase in the swallowing process. These disorders can be caused by structural, functional abnormalities or psychological problems. Dentists can actively provide patients suffering from dysphagia with comprehensive professional care, especially from the cognitive stage of food to the pharyngeal stage of the swallow. Many cases of dysphagia can be improved with careful managements based on dental professionals' knowledge, including meticulous evaluation of masticatory and swallowing functions, training on eating and swallowing, and fabrication of palatal or lingual augmentation prosthesis. The important thing is that prevention of these disorders through the oral health care instruction and planned follow-up dental visit at periodic intervals in order to manage the problems caused by anatomical, functional, and psychological reason.

• Journal of the Korea Concrete Institute
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• v.15 no.4
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• pp.522-528
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• 2003

Concrete has been considered as a semi-permanent structural material, because its excellent durability. However, such high durable structure is often attacked by some environmental condition such as chloride diffusion, carbonation and so on. In order to prevent the deterioration behaviors of concrete structures. We estimated durability of concrete when used surface treatment system and coatings by new type inorganic coating materials. Base on the results of chloride ion's diffusion test, the coated cement mortar had smaller transmitted quantity.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.335-343
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• 2008

In order to improve the workability in erecting Precast Concrete (PC) members and enhance the seismic resistance capacity of the joints in PC moment frames, a new PC column and its construction process are introduced in this paper. This column is manufactured by centrifugal force in keeping the hollow tube inside; the hollow is little bit wide and the grout can be poured from top to bottom after erection at site so that more compact grouting is possible in horizontal joint. The repeated cyclic loading test for four full scaled specimens was conducted to evaluate the seismic resistance capacity of the joint designed by the proposed system. For the continuity of main reinforcements in column, two connecting methods are used in designing specimens; one is to use mechanical connector and other is lab splice. From the cyclic lateral loading test, it was found that the seismic capacity of the developed PC column joint is comparable to that of monolithic joint.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.81-90
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• 2013

The purpose of this study is to evaluate the horizontal shear strength on the interface between PC and cast-in-place concrete for PC composite beams. Six specimens were tested to examine the structural performance of the horizontal interface with different surface condition and stirrup detailing. Except for SF-291B specimen failed in flexural compression, strengths and deformation capacities of five specimens were determined by horizontal shear failure. Horizontal shear strengths by composite horizontal shear or shear friction in current codes could be used to predict the horizontal shear capacity of the interface for specimens. Also detailing for stirrup by PCI design provision could be used to accomplish the composite action in the interface.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.19-28
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• 2013

The longitudinal axial strain in the plastic hinge region of reinforced concrete (RC) columns influences on the structural behavior of RC structures subjected to reversed cyclic loading. This strain decreases the effective compressive strength of concrete and increases the lateral displacements between stories by causing the elongation of member length. This paper investigated the effects of the axial force on the elongation of a RC member by using a sectional analysis of RC members. The analytical and experimental results indicated that the axial force decreased the axial strain in the plastic hinge region of RC columns. In this study, a model was proposed to predict the axial strain of RC columns. The proposed model considering the effects of axial force ratio consisted of three path types ; Path 1-loading region, Path 2-unloading region, and Path 3-reversing cyclic loading region. The axal strains predicted by the proposed model were compared with the test results of RC columns with various axial force ratios, and agreed reasonably with the observed longitudinal strains.

• Journal of Ocean Engineering and Technology
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• v.21 no.5
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• pp.33-38
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• 2007

The welding methods have been applied in the most structural products from multi-field of automobile, ship construction and construction, and so on. The structure steel must have enough strength of structure. In this study, SS400 steel and STS304 steel were used to estimate the corrosion characteristics of the weld thermal cycle simulated HAZ. To evaluate the corrosion characteristics, also, the materials with two conditions were used in 3.5% NaCl. The one is to the drawing with diameter of ${\Phi}10$ and the other is to the residual stress removal treatment. The electrochemical polarization test and immersion test were carried out. From test results, corrosion potential, corrosion current density, weight loss ratio and corrosion rate were measured. In the kinds of SS400 steels, corrosion potential of weld thermal cycle simulated specimens after the heat treatment showed somewhat the direction of noble potential. And in the base metal to be drawing weight loss ratio and corrosion rate occurred higher than the other kinds. In the kinds of STS304 steels, the result of base metal to be drawing was similar to results of SS400 steels, too. Two kinds of $750^{\circ}C$ and $1300^{\circ}C$ of weld thermal cycle simulation after the heat treatment were rather higher than the other kinds in weight loss ratio and corrosion rate.

• Culinary science and hospitality research
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• v.10 no.2
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• pp.149-168
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• 2004

Nevertherless, a structural depression with high expense of costs-low degree of efficiency and high price of commodities-low degree of growth during the last few years. And hotel companys were doing endeavor for conquer this depression with reshuffle of the personnal system and that systematizing an enterprise and production control. Hotel has more increase personnel expenses percents than increase sold price percents so that hotel reducing cook and as result, hotel has a problem from production selling of food service because that is insufficient of cook man power. On studying this research, an importancy of cusine department in inquire hotel and an efficiency man power control of cusine department influence on hotel marketing were made use of analysis for hotel kitchen management. The result of this study is like that. First, the quality of a hotel employee is directly related to that of hotel service, which is functioned as a principle factor on which success or failure of the hotel very largely depends. Second, fair evaluation of merits. Third, cognition for job as expert. Fourth, the roles and competences of the employees were affected much by the inner or outer environmental changes surrounding the hotel enterprises. Fifth, do not underestimate an intelligent ability and will power of employee, and hotel company have to manage that the employees consult themselves about their things of department and improve with the master sense for job. Sixth, pay increase and intensive system. This system can raise the will to achievement for employee's job, and company can get many benefits from government. Seventh, the employees should be encouraged to have memberships of academic organizations, to actively participate in academic meetings, workshops, conferences, and forums in the area of job performance.

• Survey Research
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• v.7 no.1
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• pp.1-28
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• 2006

The aim of this study is to develop a scale measuring satisfaction to ubiquitous services. Since the ubiquitous service is not vet implemented but under development, conventional scale construction methods are not directly applicable. In this study, the characteristics of items are studied by observing individual's responses after presenting a video clip describing virtual services. The constructs of ubiquitous service are defined based on those of information system and previous studies of ubiquitous services. Items were generated to reflect the constructs. In the first study, we found six factors (me-centeredness, attractiveness, usability, trust, accessibility, ownership) in the ubiquitous service scale by using exploratory and confirmatory factor analysis. Some items were dropped out that did not show good psychometric properties. In the second study, relationships among the constructs and satisfaction of the service was investigated by using structural equation models. An SEM analysis showed that these six constructs can predict the satisfaction about ubiquitous system, Practical implications and utility of this scale are discussed.

• Journal of Korean Association for Spatial Structures
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• v.12 no.3
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• pp.97-104
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• 2012

In the design procedure of the cooling tower the form-finding of the shell is the most important process, because the shape of the shell determines the sensitivity of dynamic behaviour of the whole tower against wind excitation. In engineering practice, geometric parameters of the shell are generally determined based on natural frequency analysis. 32 cooling tower shell geometries were selected through variation of the geometric parameters of an existing cooling tower shell. They were evaluated based on the first natural frequency. From the result three representative cooling towers are selected for the analysis of the structural behaviour by means of linear FE-method. As a result, a hyperbolic rotational shell with the small radius overall will yield the shell geometry with a higher first natural frequency and thus a wind-insensitive structure.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.4
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• pp.49-60
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• 2010

The actual hysteretic behavior of structural elements and systems is smooth. Smooth hysteretic behavior is more representative of actual behavior than bi-linear or piece-wise linear stiffness degrading models. The strength reduction factor in seismic design is used to reduce the elastic strength demand to design levels. In this study, the effect of smoothness on the strength reduction factor is evaluated for several smooth hysteretic systems subjected to near-fault and far-fault earthquakes. For design purposes, a simple expression of the strength reduction factor considering hysteretic smoothness and earthquake characteristics, represented as near-fault and far-fault earthquakes, is proposed. The strength reduction factors calculated by the proposed simple formulation are more similar to the factors directly obtained from inelastic response spectrum analyses than those calculated by several existing formulas.