• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.113-119
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• 2003

Since Lean Construction has been introduced as a new management approach to improve productivity in the construction industry, much research is in progress to develop lean concepts and principles for better implementation and to get results of the successful adaptation of lean ideas from manufacturing for application in the construction industry. Currently, several construction companies in the USA have applied the Last Planner System (LPS), a decentralized system developed by the Lean Construction Institute. Thus, there are demands to share information how other companies implement lean construction, to identify the benefits and barriers of lean implementation in the construction fields, and finally to improve their lean implementation. This study carried out case studies to assess current lean construction projects with the objective to find out how effectively and to what extent lean construction is being adapted by the construction industry. This study will only introduce the Last Planner which has four levels in the LPDS, findings based on interviews with project participants, and observations from the projects. This study will also provide empirically identified success factors associated with lean implementation on the construction site. Finally, the recommendations are offered to support the effort of adaptation of lean construction in the domestic construction industry. Even though lean construction still stood on the bridge crossing from current practice to lean practice, it is the researcher's conviction that lean construction would be successfully adapted to the construction industry in the near future and would be recognized as an effective management innovation.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.681-687
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• 2006

Purpose: The nose of most Koreans is characterized as a low nasal dorsum, retracted columella, and an acute columella-labial angle. For the surgical correction of the tip and columella, a modified septal extension graft, along with augmentation rhinoplasty has been developed. Methods: With this technique, a septal extension graft is fixed on the entire caudal margin of the septum (the cephalic-caudal axis) and at the same time, it is placed above the anterior nasal spine, in the membranous portion of the septum and at the base of the columella(the anterior-posterior axis). The present report describes the results obtained in 13 patients and offers an analysis of the results as judged by the columella-labial angle and 4 proportional indices(nose height index, nasal bridge length index, nasal tip projection index, columella length index), measured by photogrammetry. Results: The postoperative values obtained in these 5 categories increased significantly compared to the preoperative ones, thus confirming that the projection of tip was augmented, the nose was lengthened, and the columella was advanced caudally and lengthened. Moreover, these positive outcomes were still maintained during the follow-up period, and no side effects, such as saddle nose deformity, were reported. Conclusion: A modified septal extension graft can be considered as an effective method for the surgical correction of the nasal tip and columella in Koreans.

• Journal of Biomedical Engineering Research
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• v.28 no.4
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• pp.569-576
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• 2007

Ventricular Assist Device(VAD) has switched its goal from a short-tenn use for bridge-to-transplantation to a long-tenn use for destination therapy, With this goal, the importance of long-tenn reliability gets more interests and importances, H-VAD is an portable extracorporeal biventricular assist device, and adopts an electro-pneumatic driving mechanism. The pneumatic pressure to pump out blood is generated with compression of bellows, and is transmitted in a closed pneumatic circuit through a pneumatic line. The existing pneumatic VAD adopts a air compressor which can generate stable pressures but has defects such as a noise and a size problem. Thus, it is not suitable for being used as a portable device, These problems are covered with adopting a closed pneumatic circuit mechanism with a bellows which has a small size and small noise generation, but it has defects that improper pneumatic setting causes a failure of adequate flow generation. In this study, the pneumatic pressure regulation system is developed to cover these defects of a bellows-type pneumatic VAD. The optimal pneumatic pressure conditions according to various afterload conditions for an optimal flow rate were investigated and the afterload estimation algorithm was developed, The final pneumatic regulation system estimates a current afterload and regulate the pneumatic pressure to the optimal point at a given afterload condition. The afterload estimation algorithm showed a sufficient performance that the standard deviation of error is 8.8 mmHg, The pneumatic pressure regulation system showed a sufficient performance that the flow rate was stably governed to various afterload conditions. In a further study, if a additional sensor such as ultrasonic sensor is developed to monitor the direct movement of diaphragm in a blood pump part, the reliability would be greatly increased. Moreover, if the afterload estimation algorithm gets more accuracy, it would be also helpful to monitor the hemodynamic condition of patients.

• Journal of the Korean association of regional geographers
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• v.10 no.1
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• pp.83-95
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• 2004

Chilgok District is a historical area, which has had a certain amount of development. It has its own regional characteristics originating from its isolation from the existing built up area of Daegu City by the Kumho River This study explores the historical development processes and pending development issues of Chilgok District. In 1640 after the Japanese invasion of Korea in 1592, the district upgraded into Chilgok Dohobu due to its importance as a transportation hub of Youngnamdaero(the main road of Youngnam province in Chosun Dynasty). In its early stages, the government office was located in Kasan fortress, later the of office was moved to Eupnae-Dong. The Chilgok district has experienced a developmental lag resulting from the office's removal to Waegwan, located on the Kyungbu railroad since 1914. Later, due to the increasing influence of nearby Daegu City, urbanization continued gradually. Finally in 1981 Chilgok district was officially incorporated into Daegu Metropolitan City. In the later 1980s, the housing land development project was applied into the district centered on the alluvial plain of Palgeo-Cheon(stream) of the Northern part of Taejun-Bridge. Although the old built up zone was excluded from public sector development projects, private sector development has made the zone a modern town. Now, Chilgok district has transformed into a high-density residential new town in which high-rise apartment complexes mingle with numerous houses. As the district has developed, traffic jams have become a hot issue and it is going to get worse than now as the development continues. To solve this problem, Daegu city needs to swiftly construct the fourth belt way and the third subway line.

• Clinical and Experimental Pediatrics
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• v.52 no.2
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• pp.242-246
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• 2009

The clinical features of ring chromosome 13 include mental and growth retardation, CNS anomalies, facial dysmorphism, cardiac defects, genital malformations, limb anomalies, skeletal deformities and anal malformations. Although many cases of ring chromosome 13 have been reported worldwide, only 6 cases have been reported in Korea, and the latter cases were not mosaic but pure ring chromosome 13. Here we report a case with mosaic ring chromosome 13. The baby boy was born at 37 weeks of gestation by induced vaginal delivery due to intrauterine growth restriction (IUGR). He was the second baby of a 28-year-old hepatitis B carrier mother and a 32-year-old father. There was no family history of chromosomal anomalies. The baby was a symmetric IUGR with a birth weight of 1,860 g, length of 44.8 cm, and head circumference of 29.4 cm. The physical examination revealed microcephaly, trigonocephaly, flat occiput, large ears, short neck and dysmorphic facial features, including microophthalmia, hypertelorism, antimongoloid slanting palpebral fissures, a flat nasal bridge, and micrognathia. The karyotype of this patient performed by peripheral blood lymphocytes was 46,XY,r(13)(p13q34)/45,XY,-13/46,XY,dic r(13;13)(p13q34;p13q34). The baby showed failure to thrive, hypotonia, and developmental delay. We report the first case of mosaic ring chromosome 13 in a male baby in Korea and compare this case with other Korean cases of non-mosaic ring chromosome 13.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.137-145
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• 2004

Limestone zone in korea have been distributed to diagonal line so that it is wide from the Gangwondo to the Jeonlanamdo. The limestone cavity and fractured zone were formed by chemical weathering. Limestone cavity and fractured zone was reinforced with cemented milk(w/c=60%)by high pressure jet grouting by tripple -pipe to establish bridge foundation on the ground condition like limestone cavity. To analyze property of limestone and solid of cement milk(w/c=65%), mixed solid of cement, core NX size in the limestone cavity and fractured zone and compressive strength. Seismic tomograpy exploration was pcrforn1cd to analyze deformation modulus of limestone. The analysis suggests that deformation modulus of limestone has effect on uniaxial compressive strength, seismic velocity, seismic elasticity modulus. Average static elasticity modulus of limestone is $5.08{\times}10^5kgf/cm^2$, cement and coal mixed solid is $0.25{\times}10^5kgf/cm^2$, $0.095{\times}10^5kgf/cm^2$. Average seismic velocity of limestone is 5.240m/sec, cement and coal mixed solid is 2,211.3m/sec, 1,447.5m/sec. Average uniaxial compressive strength of limestone was $1,221.3kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $125.22kgf/cm^2$, $35kgf/cm^2$ each other. Average friction angle of limestone was $49.14^{\circ}$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $38.39^{\circ}, 25.83^{\circ}$ each other. Average cohesion of limestone was $137.7kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $23.5kgf/cm^2$, $15.5kgf/cm^2$ each other. Average deformation modulus of limestone was $2.84{\times}10^5kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $0.4{\times}10^5kgf/cm^2, 0.12{\times}10^5kgf/cm^2$ each other. It was analyzed that the elasticity and uniaxial compressive strength, seismic velocity of solid of cement milk mixed limestone pieces and coal had an highly interrelation regardless of existence of limestones pieces and coal but it had shown that limestones had an lower interrelation. In case of field seismic velocity and deformation of limestone, SIC solid of cement milk mixed with coal and limestone pieces had an highly interrelation.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.1-8
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• 2010

Clients require easy to use of product and operating and industry safety according to the change of a market and a factory. For overcoming it, this paper developed controller of take-out robots that take high speed and superprecision and supplement a week point as use the system based on network. development controller classify teaching pendant and center server PC. Center server PC service the information about all process to supervisor. Teaching pendant is the bridge that service various faculties such as control, user recognition, metallic pattern operation to the user using injection molding. The controller development for taking out injection molded body classify software and hardware. The development of software is divided into three step which is application program, user interface and device driver. the simple device driver is not classified and included in application program. The hardware induce the touch panel and wireless network and construct the effective process control and internet connection. The inject ion cycle of existing system was five second but advanced system has the inner four cycle, process efficiency and product operation through wireless network.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.214-220
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• 2013

Implant prosthodontics is beneficial for edentulous patients in enhancing the support, retention, stability, phonation and so on. Various types of prosthesis supported by implant, including implant retained- or supported- overdenture for the removable type and ceramo-metal and fixed prostheses with processed acrylic teeth for the fixed type, are frequently used. Treatment planning for the prosthesis with implant must be made after considering individual characteristics such as form of residual ridge, soft tissue, interocclusal relationship, economic status. Fixed prosthesis with processed acrylic teeth (also known as 'implant hybrid prosthesis' or 'bone anchored bridge') has the advantages of both removable and fixed prosthesis such as proper soft tissue profile, esthetic outcome, increased masticatory efficiency and psychological stability. The 73-years-old female patient came to the department of prosthodontics, Dental hospital of Yonsei University. She was diagnosed with Kennedy class I partial edentulism in the maxilla and complete edentulism in the mandible. This article reports a satisfactory clinical and esthetic outcome of full mouth rehabilitation using removable partial denture in the maxilla and implant hybrid prosthesis in the mandible.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.47-67
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• 1996

The purpose of this study was to observe the effect of $Biocoral^R$ graft and bioglass 45S5 graft in combination with ePTFE membrane in periodontal osseous defects for new bone formation. Nine healthy dogs were used. Under general anesthesia, 3-wall defects were created on the mesial and distal surfaces of the maxillary right canines, the mesials of the maxillary right second premolars, the distals of the mandibular right canines and the mesials of the mandibular right third premolars. To induce periodontitis, a silicone rubber, $Provil^R$ light body, was injected under pressure into the defects. Ninety days later, $Provil^R$was removed and followed by thorough root planing. The followings were then applied in the mesial and distal defects of the maxillary right canines, the mesials of the maxillary right second premolars, the distals of the mandibular right canines and the mesials of the mandibular right third premolars by random selections : 1) ePTFE membrane only application, 2) $Biocoral^R$ graft, 3) $Biocoral^R$ graft and ePTFE membrane application, 4)Bioglass 45S5 graft, 5) Bioglass 45S5 graft and ePTFE membrane application. The membranes were removed 1 month later. The dogs were sacrified at 1, 2 and 3 months following the graft, and block sections were made, demineralized, embedded, stained and examined by light microscope and transmission electron microscope. On the sections from teeth treated with ePTFE membrane only, the defect demonstrated extensive connnective tissue and alveolar bone regeneration. The $Biocoral^R$ graft group demonstrated extensive bone regeneration compared with ePTFE membrane only group. In the $Biocoral^R$ graft plus ePTFE membrane group, regeneration of new alveolus and crest occurred within the defect. As the experimental period lengthened, bone regeneration was increased and bone bridge was formed among the graft particles. The but bioglass 45S5 graft group demonstrated extensive bone regeneration but the amount of new bone was less than that of the $Biocoral^R$ graft group. For the bioglass 45S5 graft plus ePTFE membrane group, the amount of new bone was also increased. As the experimental period lengthened, bone regeneration was increased. Multinucleated giant cells, fibroblasts and macrophages were observed. As the bone formation was increased, the number of such cells was decreased. In conclusion, the $Biocoral^R$ was found better than the bioglass 45S5 for new bone formation, and the use of ePTFE membrane alone or with $Biocoral^R$/bioglass 45S5 can be supported as potential methods of promoting bone formation.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.333-343
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• 2000

The purpose of this study was to compare the effect of ferric sulfate and formocresol as pulp dressing agents in pulpotomized teeth of dogs. 40 teeth of 5 dogs, weighting 10kg. were used in this study. The animals were sacrificed at the intervals of 3, 7, 14, 28 and 56 days for histopathologic evaluation. The specimens were observed by the light microscope. The results were as follows : 1. Inflammatory response was observed in both groups, but pulp tissue of ferric sulfate group was showed lesser inflammatory degree and more rapid recovery than that of formocresol group. 2. In ferric sulfate group odontoblasts showed irregular arrangement pattern at initial stage and returned to regular pattern after 2 weeks. But in formocresol group. continued irregular pattern of odontoblast was observed during experimental period. 3. Reparative dentin was produced widely along the canal in one specimen of formocresol group at 8 weeks and dentinal bridge was formed in two specimens of ferric sulfate group at 8 weeks.