• The korean journal of orthodontics
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• v.48 no.6
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• pp.367-376
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• 2018

Objective: This study was performed to investigate the changes in alveolar bone after maxillary incisor intrusion and to determine the related factors in deep-bite patients. Methods: Fifty maxillary central incisors of 25 patients were evaluated retrospectively. The maxillary incisors in Group I (12 patients; mean age, $16.51{\pm}1.32years$) were intruded with a base-arch, while those in Group II (13 patients; mean age, $17.47{\pm}2.71years$) were intruded with miniscrews. Changes in the alveolar envelope were assessed using pre-intrusion and post-intrusion cone-beam computed tomography images. Labial, palatal, and total bone thicknesses were evaluated at the crestal (3 mm), midroot (6 mm), and apical (9 mm) levels. Buccal and palatal alveolar crestal height, buccal bone height, and the prevalence of dehiscence were evaluated. Two-way repeated measure ANOVA was used to determine the significance of the changes. Pearson's correlation coefficient analysis was performed to assess the relationship between dental and alveolar bone measurement changes. Results: Upper incisor inclination and intrusion changes were significantly greater in Group II than in Group I. With treatment, the alveolar bone thickness at the labial bone thickness (LBT, 3 and 6 mm) decreased significantly in Group II (p < 0.001) as compared to Group I. The LBT change at 3 mm was strongly and positively correlated with the amount of upper incisor intrusion (r = 0.539; p = 0.005). Conclusions: Change in the labial inclination and the amount of intrusion should be considered during upper incisor intrusion, as these factors increase the risk of alveolar bone loss.

• Earthquakes and Structures
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• v.11 no.2
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• pp.195-215
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• 2016

Rehabilitation of historical unreinforced masonry (URM) buildings is a priority in many parts of the world, since those buildings are a living part of history and a testament of human achievement of the era of their construction. Many of these buildings are still operational; comprising brittle materials with no reinforcements, with spatially distributed mass and stiffness, they are not encompassed by current seismic assessment procedures that have been developed for other structural types. To facilitate the difficult task of selecting a proper rehabilitation strategy - often restricted by international treaties for non-invasiveness and reversibility of the intervention - and given the practical requirements for the buildings' intended reuse, this paper presents a practical procedure for assessment of seismic demands of URM buildings - mainly historical constructions that lack a well-defined diaphragm action. A key ingredient of the method is approximation of the spatial shape of lateral translation, ${\Phi}$, that the building assumes when subjected to a uniform field of lateral acceleration. Using ${\Phi}$ as a 3-D shape function, the dynamic response of the system is evaluated, using the concepts of SDOF approximation of continuous systems. This enables determination of the envelope of the developed deformations and the tendency for deformation and damage localization throughout the examined building for a given design earthquake scenario. Deformation demands are specified in terms of relative drift ratios referring to the in-plane and the out-of-plane seismic response of the building's structural elements. Drift ratio demands are compared with drift capacities associated with predefined performance limits. The accuracy of the introduced procedure is evaluated through (a) comparison of the response profiles with those obtained from detailed time-history dynamic analysis using a suite of ten strong ground motion records, five of which with near-field characteristics, and (b) evaluation of the performance assessment results with observations reported in reconnaissance reports of the field performance of two neoclassical torsionally-sensitive historical buildings, located in Thessaloniki, Greece, which survived a major earthquake in the past.

• Journal of Information Technology Services
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• v.18 no.5
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• pp.209-224
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• 2019

When evaluating the performance of a NPD(New Product Development) project, it is common to evaluate the project performance according to the achievement of the planned goal in terms of time, quality and cost management, which are usually three main constraints of the project. The evaluation of the financial factors by which sales contributed to the return of the company is more influential. This is why companies need to increase sales and raise profits. Therefore, it is more reasonable to evaluate the sales performance of NPD projects over a certain period of time against the input costs. At this time, we can analyze the causes of inefficient projects and compare them with other projects and find out how to improve the sales performance to help the company increase its competitiveness. In this paper, we analyze the relative efficiency of the sales performance on the input of the projects by using the actual sales in the period of one year after mass production of the NPD projects of 'S' company in ICT industry. Input factors include developer resource and development cost for the NPD reported after the project has been completed, the delay weeks for the schedule targeted at the project planning stage, and the number of quality issues due to development design faults during initial mass-production. The sales figure and the contribution margin of the product after one year from the start of mass production are defined as the output factors. In this paper, we analyze the efficiency of the projects by using data envelope analysis (DEA). As a result, we found out the reason of the inefficient project of DMUs according to the differences in the characteristics of the efficient and inefficient B2B markets based on the result of DEA of NPD projects. Thus, the goal of this paper is to identify strategies for improving sales performance of NPD projects in inefficient markets.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1219-1228
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• 2015

The Fixed Area ARFs (Area Reduction Factors) method has limitations in providing exact information about spatial distribution due to the lack of enough density of rain gauge stations. In this study the storm-centered ARF was evaluated between frontal and typhoon storm events utilizing radar precipitation. In estimating storm-centered ARFs, in order to consider the horizontal advection, direction, and spatial distribution of rain cells, the rotational angle of rainfall of each rainfall event and the optimum areal rainfall within the spatial rain cell envelope was taken into account. Compared with the frontal storm, the ARF of typhoon storm shows narrow range of variability. It is noted that the ARFs of frontal storm increases with the rainfall duration, but those of typhoon storm shows opposite pattern. As a result the typhoon ARFs appear greater than frontal ARFs for 1~3 hours of duration, but less for more than 6 hours of duration.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.69-77
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• 2003

One directional and biaxial tension tests of 13 reinforced concrete panels were conducted to derive a constitutive law of concrete. Based on the test results, a model equation is derived for the stress-strain relationship of concrete in tension. Main test variables are reinforcement ratio and the load ratio applied in two directions. In addition a failure envelope of concrete in tension-tension region is suggested based on the initial crack occurrence. Test results show that the concrete carries substantial tensile stress even after cracking occurrence. However, the application of this proposed stress-strain relationship for concrete is limited to the case where the direction of reinforcement coincides with the direction of the applied principal stresses.

• Journal of Korean Academy of Nursing
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• v.30 no.4
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• pp.857-868
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• 2000

The purpose of the present study is to identify the mediation effect of hope between fatigue and psychosocial adjustment in women with breast cancer. The framework for this study was guided by concepts and propositions derived from the theoretical and empirical literature on fatigue, hope and adjustment. The design of this study is a descriptive correlation study using a cross-sectional design. One hundred and twenty two outpatients with early breast cancer, receiving post-surgical radiation therapy or chemotherapy, were selected from three major medical centers in Seoul, Korea. A packet including PABCF (Psychosoical Adjustment to Breast Cancer Factor), revised RPFS (Revised Piper Fatigue Scale), HHI (Herth Hope Index), and self-addressed return envelope was given to the participants at seven to eight weeks post surgery. The questionnaires were to be completed at home and returned to the researcher by mail. The obtained data were analyzed using three regression equations guided by Baron and Kenny (1986); first, hope was regressed on fatigue; second, psychosocial adjustment was regressed on fatigue; and third, psychosocial adjustment was regressed on fatigue and hope, simultaneously. In the first equation, fatigue explained 4% of the variance in hope. In the second equation, fatigue explained 47% of the variance in psychosocial adjustment. In the last equation, hope and fatigue significantly explained the variance in psychosocial adjustment. Therefore, all conditions for the test of mediation effect of hope were satisfied. For the test of the mediation effect, the beta coefficients of fatigue on psychosocial adjustment on the second and third regression equations were compared. The beta coefficients were decreased from .69 (p < .001) on the second regression equation to .63 (p < .001) on the third regression equation. Thus, the hypothesis of this study was supported. As a result of this study, the negative Influence of fatigue on psychosocial adjustment is dampened through the mediator effect of hope in women with breast cancer. Therefore, when planning care for the adverse effect of fatigue on psychosocial adjustment, oncology nurses should consider hope as a mediator between fatigue and psychosocial adjustment to breast cancer.

• Applied Microscopy
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• v.30 no.4
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• pp.367-376
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• 2000

The observation using an electron microscope shows that the maturation of the oocyte of African giant snail, Achatina fulica, proceeds over three stages. The oocyte of stage 1 is a small elliptic cell $(220\times400{\mu}m)$ whose light nucleoplasm contains two nucleoli. In its cytoplasm, a number of mitochondria, rough endoplasmic reticula, and ribosomes are found, while yolk granules are not. The nucleus of the oocyte of stage 2 is relatively large in comparison with the volume of cytoplasm, and contains one nucleolus. In the nuclear envelope comprising inner and outer double membrane, there are found a lot of nuclear pores for materials to pass through. A number of mitochondria, Golgi complex and lipid yolk granules appears in the cytoplasm, and proteinous yolk granules begin to form and mature in the vacuoles of various sizes ($0.8\sim3.0{\mu}m$ in diameter). The oocyte of stage 3 has an enlarged nucleolus. Material transportation through nuclear pore is not found any longer. The cytoplasm in this stage is filled with proteinous and lipid yolk granules. The microvilli are developed around the egg plasma membrane.

• Journal of Plant Biology
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• v.34 no.2
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• pp.129-136
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• 1991

Two cell types, tip cells and hyphal cells, were found at the front of Cuscuta australis endophyte growing into the stem parenchyma of the host plant, Trifolium repens. Each tip cell developed into an elongate, filamentous hypha. The cells of both types possessed a dense cytoplasm including abundant organelles and enlarged nuclei with the deeply lobed envelope. The unevenly thick walls were observed in certain tip cells. The wall penetrated through the middle lamellae of the host cells and engulfed the debris of broken host cells. Some front cells had the plasmalemma-wall invaginations, which increased the surface area and would facilitate material uptake from the host No plasmodesmata between the host and parasite cells were found; instead, an apoplastic continuity was established by fused cell walls at the interface of the two partners. The apoplast was thought to be the main route for water and nutrients transport.nsport.

• The korean journal of orthodontics
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• v.13 no.2
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• pp.165-176
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• 1983

The hyalinized zone in compressed periodontal ligament seems to be an unavoidable aspect during certain phases of orthodontically produced tooth movement. And these hyalinized zones leads to a standstill of tooth movement. But when hyalinized zones disappears after a certain period of time and tooth movement is established. In the basic aspect of clinical science of orthodontics, it is very important, to study about the process involved and to establish whether a difference of periodontal response by the amount of the applied experimental force exists. The 35 Guineapigs were divided into the control group (5 animals) and the experimental group (Group I-Group VI 30 animals). The experimental tooth movement of Guineapig's maxillary incisors were carried out by rendering continuous force, 5g (Group I, Group II) 35g (Group III, Group IV), 100g (Group V, Group VI) respectively. 15 animals (Group I, Group III, Group V) were sacrificed one week after this experiment. Another 15 animals (Group II, Group IV, Group VI) were sacrificed one week after the removal of active appliences. At the end of the experimental periods, specimens containing tooth and adjacent periodontal structure were obtained and processed for light and electron microscopy. The results were as follows: 1. In Group I, cellular changes of pressured zones showed swollen mitochondria, dilation of rough surfaced endoplasmic reticulum (RER), vesicles and pyknosis of nucleus. 2. In Group III and Group V, the hyalinized tissues showed cell necrosis accompaning ruptures of cytoplasmic membrane and perinuclear envelope, large cytoplasmic vacuoles and many necrotic cell debris. 3. In Group IV and Group VI, hyalinized tissue were eliminated and the primitive mesenchymal cells and blood capillaries were proliferated. 4. In group V, the destruction of the collagenous fibers were observed, while in group I and group III were not observed. 5. In Croup IV and Group VI, the hyalinized zones were still remained partly.

• Journal of Korean Foot and Ankle Society
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• v.1 no.1
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• pp.30-37
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• 1997

Pilon fracture is an intraarticular fracture of distal tibia. It is high energy injury with significantly associated soft tissue damage, bone comminution, and articular surface disruption. Until recently, this treatment has followed the AO principles, Because the risk of complications outweighs potential benefits, the principle of a Pilon fracture treatment are changing. Newer techniques using articulated external fixation minimize disturbance of the soft tissue envelope and have decreased these complications. Series of 5 patients with Pilon fracture were treated by articulated external fixator and followed up more than 12 monthes at the Department of orthopaedic surgery, Kang Dong Sacred Heart Hospital, College of medicine, Hallym University. The results were as follows: 1. The type of fracture were type C2(3 cases),type C3(2 cases) according to AO-$M{\ddot{u}}ller$ classification. 2. The clinical results according to functional criteria by Mast and Teipner were good in 4 cases and poor in 1 case, which is an old fracture. 3. Techniques utilizing articulated external fixator were associated with satisfactory results and appeared to significantly decrease the incidence of soft tissue complication, post-traumatic arthritis, osteoporosis, and fibrosis of ankle joint.