• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.2
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• pp.19-27
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• 1989

Hemifacial microsomia is characterized underdevelopment of the TMJ, mandibular ramus, and associated muscles of mastication. The Maxilla and malar bones on the affected side frequently are underdeveloped. The contiguous parotid gland may be hypoplastic. Preauricular sinus tracts and tags may exist, along with underdevelopment of the associated external ear, and affected facial nerve and muscles of facial expression may also show dysfunction. Children exhibiting the more classic signs will be identified at birth. Little is known about the etiology of hemifacial microsomia. We have corrected surgically a 22-year-old woman with hemifacial microsomia. We have performed leveling Le Fort I osteotomy with iliac bone graft on the maxilla, reverse-L osteotomy and iliac bone graft on the right mandibular ramus, vertical ramus osteotomy on the left side, onlay bone graft on the right mandibular body, and augmentation genioplasty. The postoperative course was uneventful and restoration of facial asymmetry was achieved.

• Journal of the Korea Institute of Building Construction
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• v.10 no.3
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• pp.57-64
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• 2010

This study is to analyze the effects of aluminum form surface coating material on surface quality of concrete. When observing the surface quality of concrete affected by the change of aluminum form surface coating material, in general, as the number of use of the coating material increased, the surface quality of concrete decreased and good surface quality was shown in plywood (hereinafter PW). For epoxy (hereinafter EP) resin, when applying form remover, good surface quality was shown. For the surface roughness of concrete by the application form oil of form remover and the number of use of the coating material, as the number of use increased, highest surface roughness value was shown which meant the leveling was bad, but the surface roughness value in EP and PW was the lowest. Just for EP, when applying form remover, surface roughness value was low. For the number of void for concrete by the application of form remover and the number of use of the coating material, In general, the number of void which was generated when applying form oil the remover decreased.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.6
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• pp.567-582
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• 2000

We propose a new way of managing flash memory space for flash memory-specific file system based on log-structured file system. Flash memory has attractive features such as non-volatility, and fast I/O speed, but it also suffers from inability to update in place and limited usage cycles. These drawbacks require many changes to conventional storage (file) management techniques. Our focus is on lowering cleaning cost and evenly utilizing flash memory cells while maintaining a balance between the two often-conflicting goals. The proposed cleaning method performs well especially when storage utilization and the degree of locality are high. The cleaning efficiency is enhanced by dynamically separating cold data and non-cold data. The second goal, cycle-leveling is achieved to the degree where the maximum difference between erase cycles is below the error range of the hardware. Simulation results show that the proposed method has significant benefit over naxve methods: maximum of 35% reduction in cleaning cost with even spreading writes across segments.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.271-279
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• 1985

The authors treated a case of bimaxillary dentoalveolar protrusion corrected by anterior segmental osteotomies: As presurgical treatment & process, closing of the upper anterior spacing with fixed appliances was worked out, cephalometric predicition & model surgery was done, and fabrication of intra-arch acrylic resin splints were made. It was not necessary to make an intermaxillary fixation with wire after surgery. Only intramaxillary fixation of anterior retracted mobile segment with resin plate was required for 8 weeks. After surgical treatment, leveling of the upper and lower arch with rectangular arch wire were accomplished as the Intrusion of anterior teeth proceeded. We will continue to improve the class II molar relationship by using class II elastics and have a good occlusiion through the orthodontic treatment.

• Journal of Internet Computing and Services
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• v.2 no.3
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• pp.19-25
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• 2001

An educational system using computers was first conceptualized by Dr. Donald Bitzer in the University of Illinois in the late 1950s. Since the PLATO system was developed in 1961, multilateral research were made for the last 30 years. Especially, the development of Internet and Information Technology has contributed to the advancement of the distance education system. This system has greatly changed the existing educational paradigm, As the result, new education system is being realized, This study suggests a distance education system based on ‘push’ technique, which is a means of active information transmission, In this system, the ‘push’ technique is combined with the existing distance education system. Through the combination, learning contents can be provided for learners without connecting the DB on the Internet. In addition, the process of getting new information is real-timed operation. Also, the treatment of item; and the algorithm of level-based item evaluation are devised in consideration of various levels of learners, so that evaluation of items appropriate to the levels of learners can be accomplished.

• Fire Science and Engineering
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• v.21 no.3
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• pp.69-77
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• 2007

Our country automatic wet pipe sprinkler system of hydraulically designed system has not deviated from the pipe regulation process, therefore we face limitations when using an independent method to hydraulically designed system. Therefore. after reviewing a developed country's methods using the drainage-density concept, we found it necessary for our country to introduce the drainage-density concept. Currently, under the National Fire Safety Codes(NFSC), this does not solve the problem and the limitation of hydraulically designed system because different problems arise depending on where the head was installed. To make improvements, first, such as the developed country, overcome the difference by introducing the drainage-density concept to determine the amount of drainage. Second, by using diverse head caliber and decreasing the limits on the amounts of distribution, we can expect a leveling off of the drainage density. Third, using the increase of hydraulically designed system through the application of the rule to hydraulically designed system, finally, development to performance based fire protection design.

• Journal of the Korean Wood Science and Technology
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• v.1 no.2
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• pp.3-10
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• 1973

This study was carried out to examine the characeristics of waste sanders(S)from. plywood and pre-finishing plywood surface sanding and double saw finishing, as a new extander in urea-formaldehyde resin(UFR) in plywood adhesive, and to focus, adhesive strength using the glue extended with milled sanders(MS) as extender, leveling the optimum amount of MS to be added, and examining the physical properties of glue extended MS & S. Also economical good feasibility of substitution for wheat flour(WF) with MS as a new extender is analyzed and presented in details. Selecting three standard samples of 80, 100 and 180 mesh, sorking them in distilled water at $20^{\circ}C$, 24 hours, redrying at $105^{\circ}C$ and rescreening the sample with standard screen, again, the 3 samples of 80, 100, and 180 mesh are passed 23 percent through 80 mesh sander standard sample 27 percent through on 100 mesh and only 10.9 percent through 180 mesh, respectively. The particle size of retained parts are greater in size of redried form. It seems undoubtly that particles to be extended in glue are got swollen and become greater in size and coarser in shape. The shape of fresh S particles are irregular thin needle with small scale, as shown in Figure 5. PFS are so finer than plywood S that only 9.8 percent of the S retained on 100 mest screen, 24. 30 percent on 100-160 mesh, and 65.9% on 160-180 mesh. But particle size of the fresh S is large enough to make the viscosity of glue direct extended with S too high to apply it glue spreader. The glue extended with milled sanders(MS). 3 hours milled PFS or 6 hours milled plywood S, having particle sizes shown in Tables 7 and 8, as ratio of Reain/MS/WF/water: 100/8/8/10, indicate good viscosity of 16 to 24 ps, as shown in Figure 5, for applying direct to glue spreader, have high tensile-shear strength (adhesive strength), 102.4 kp/$cm^2$, and 94 percent wood failure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.996-1001
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• 2006

Automatic washing machines have been improved and popularized steadily since the first electric washing machine was produced in the early 1900's. Appliance industry has tried to obtain the performance of washing machine with large capacity, high energy efficiency, low vibration and low noise levels. As the installation peace of a washer becomes closer to the living space, vibration and noise problems become more important challenges. In general, a washing machine has four legs to support its body. Four legs of the washing machine should be attached on a floor. If not so, it may cause severe vibration or walking in the spin-drying process. Unfortunately, the floor of an ordinary house is bumpy in general, and the consumers will not accept bolting washing machines to a foundation; moreover, sometimes they move the location of their washing machines to utility rooms or bath rooms or kitchens and don't care for leveling the legs exactly. In this study, we devise an auto-leg system that prevents the occurrence of abnormal vibration and walking of washing machines. It is simply composed of a spring and a friction damper. Some experiments are implemented to show the dynamic characteristics of the three-dimensional auto-legged washing machine model that is located on the even or uneven ground. A spring parameter is optimized to adjust the length of the auto-leg system automatically up to 10 mm irregularity, and the friction damper is designed to decrease a resonance induced by the spring of the auto-leg system. Some numerical results show that placing the proposed auto-leg system in a washing machine makes good performance with low vibration, as well as low noise, regardless of the unevenness of the floor.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.480-484
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• 2012

Concrete, the mixture of cement, sand, gravel and water, is a suspension substance extensively used to construct building materials. When a concrete mortar is applied to the underwater construction, the rheology of concrete is of great importance to its flow performance, placement, anti-washout and consolidation. In this research, the anti-washout and rheological properties of concrete have been investigated with concrete admixtures prepared by adding anionic surfactants, cationic surfactants, and polymeric thickeners. The concrete mortar formulated by pseudo-polymeric systems with the electrostatic association of anionic and cationic surfactants, showed high viscosities and suitable anti-washout properties, but poor pumpabilities. The addition of poly methyl vinyl ether to the mixed surfactant system exhibits synergistic effects by improving the concrete mortar properties of the concrete mortar such as fluidity, visco-elastic property, self-leveling, and anti-washout.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.3
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• pp.331-345
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• 2009

This study aims to standardize the work classification system in spatial data. Up to now, a systematic standard for constructing process and quality management has not yet been established in Korea, thus, it is possible for the national budget to be wasted. The regulations related to constructing spatial data are also obscure, and absurd for feasible application to reality, which results in a lack of reliability of the quality of spatial data. This study was conducted by investigating and analyzing regulations related to spatial data quality and various literature, including studies on spatial data quality conducted by the NGII. And also, the study was conducted by investigating and analyzing the constructing processes and working methods of major firms that have experience in constructing a GIS for a local governing body. Based on the analyzed data, we standardized work classification and management methodology for control point surveying using GPS, leveling, aerial photographing, digital mapping, topographic mapping, digital elevation modeling, aerial photographic DB construction, digital orthophotomap.