• Geotechnical Engineering
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• v.13 no.5
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• pp.101-124
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• 1997

The root pile system is insitu soil reinforcement technique that uses a series of reticulately installed micropiles. In terms of mechanical improvement by means of grouted reinform ming elements, the root pile system is similar to the soil nailing system. The main difference between root piles and soil nailing are due to the fact that the reinforcing bars in root piles are normally grouted under high pressure and that the alignments of the reinforcing members differ. Recently, the root pile system has been broadly used to stabilize slopes and retain excavations. The accurate design of the root pile system is, however, a very difficult tass owing to geometric variety and statical indetermination, and to the difficulty in the soilfiles interaction analysis. As a result, moat of the current design methods have been heavily dependent on the experiences and approximate approach. This paper proposes a quasi-three dimensional method of analysis for the root pile system applied to the stabilization of slopes. The proposed methods of analysis include i) a technique to estimate the change in borehole radium as a function of the grout pressure as well as a function of the time when the grout pressure is applied, ii) a technique to evaluate quasi -three dimensional limit-equilibrium stability for sliding, iii) a technique to predict the stability with respect to plastic deformation of the soil between adjacent root piles, and iv) a quasi -three dimensional finite element technique to compute stresses and dis placements of the root pile structure barred on the generalized plane strain condition and composite unit cell concept talon형 with considerations of the group effect and knot effect. By using the proposed technique to estimate the change in borehole radius as a function of the grout pressure as well as a function of the time, the estimations are made and compar ed with the Kleyner 8l Krizek's experimental test results. Also by using the proposed quasi-three dimensional analytical method, analyses have been performed with the aim of pointing out the effects of various factors on the interaction behaviors of the root pile system.

• Journal of Periodontal and Implant Science
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• v.45 no.4
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• pp.128-135
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• 2015

Purpose: The aim of this study was to determine the effect of overlaying titanium mesh (TM) with an adjunctive collagen membrane (CM) for preserving the buccal bone when used in association with immediate implant placement in dogs. Methods: Immediate implant placements were performed in the mesial sockets of the third premolars of five dogs. At one site the TM was attached to the fixture with the aid of its own stabilizers and then covered by a CM (CM group), while the contralateral site received only TM (TM group). Biopsy specimens were retrieved for histologic and histomorphometric analyses after 16 weeks. Results: All samples exhibited pronounced buccal bone resorption, and a high rate of TM exposure was noted (in three and four cases of the five samples in each of the TM and CM groups, respectively). A dense fibrous tissue with little vascularity or cellularity had infiltrated through the pores of the TM irrespective of the presence of a CM. The distances between the fixture platform and the first bone-implant contact and the bone crest did not differ significantly between the TM and CM groups. Conclusions: Our study suggests that the additional use of a CM over TM does not offer added benefit for mucosal healing and buccal bone preservation.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.4
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• pp.47-62
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• 2016

As the occupational education in junior college is being searched to be connected to practical industrial settings at present, importance of field placement is now being heightened. Industrial field experience shall be developed as the work can be performed in the practical site based on the generally comprehensive contents through the applicable educational course rather than simply independent educational course. Furthermore, characteristics of the applicable major shall be reflected in the field placement to be connected to the industrial field experience so that image promotion of the major and other additional value of the major can be effectively operated. However, it is practical situation that most of the field placements are being operated separately from connection and characterization of the educational curriculum in spite of the variety of the industrial field experiences and works in the field sites. Thus, the author of the thesis would analyze practical cases of the industrial field experiences in the past and grasp the problems of them so that we can develop models of the industrial field experiences proper for characteristics of fashion related departments. Especially, through the study the author of the thesis has developed the practical educational model where the fashion majoring educational courses can be connected with the field placement in the school industry in which the practical environment is established as in the applicable industry. In addition, it is judged that Developed educational models can be realized for subsidiary companies with close relationship with the departments besides the school based enterprises.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.157-158
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• 1998

The purpose of this study was to test the hypothesis that even very small change of the cue direction in the treatment of the early osteonecrosis could affect the outcomes of operation. For this, the changes in stress transfer within the necrotic area of the femoral head were investigated under various directions and placements of the core utilizing finite element method. The loading of 3188N, which represents after-heel-strike, was imposed in cubic cosine pattern. All nodes on the most distal surface of the model were constrained in all directions. All materials included were assumed to have linear-elastic behavior. The result says that the critical stress, which causes collapse of the femoral head, was reduced when the core was oriented toward the posterior side of the femoral head regardless of location of the necrotic area. The same result was obtained either fibular bone grafting or cementation was adopted. As a consequence, the biomechanical study suggests that the core should be directed toward the loading point where the resultant force is applied to get more desirable treatment of the osteonecrosis of the femoral head in the early stage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.4
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• pp.220-227
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• 2020

Objectives: Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder. These patients lose their teeth at a young age and are in need of prosthetic rehabilitation. The aim of this systematic review was to assess the success of dental implant placement in these patients. Materials and Methods: An electronic search was performed in PubMed Central, Scopus, and Web of Science using the keyword "Papillon-Lefèvre syndrome" AND "dental implant" OR "prosthodontics". Articles reporting implant placement in patients with PLS until July 2019 were included. Results: Assessment of the included 11 articles reporting 15 cases showed 136 implant placements in these patients. Implant failure occurred in 3 patients (20 implants). The peri-implantitis and failure rate was higher in the maxilla. Meta-analysis showed the probability of failure to be 7% (95% confidence interval [CI] 0%-31%) for maxillary implants and 2% (95% CI 0%-9%) for mandibular implants. The follow-up time ranged between 1 and 20 years. Healing after bone graft and implant placement in these patients was uneventful. Conclusion: Dental implants may be a viable treatment option for PLS patients. Implantation can help preserve alveolar bone if the patients' immunological and growing conditions are well-considered and proper oral hygiene and compliance with the maintenance program are continued.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.12A
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• pp.1286-1295
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• 2007

This paper proposes, based on a bandpass sampling theory, a novel method to find valid sampling frequency range and minimum sampling rate with low computational complexity for downconversion of N bandpass radio frequency(RF) signals, under application of all possible signal placements(full permutations) in a IF stage. Additionally, we have developed a complexity-reducing method to obtaine the opttimal and minimal sampling rate for supporting the user-wanted guard-band or spacing between adjacent downconverted signal spectrums. Moreover, we have verified through comparisons with other methods that the proposed methods have more advantageous properties.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.103-109
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• 2012

The purpose of this paper is to suggest the strategical lifting postures able to alleviate imbalanced EMG amplitude leading to an increase in low back muscle fatigue while lifting asymmetric load dynamically. Eleven male subjects are required to lift symmetrically an external load with 15.8kg and load center of gravity (LCG) deviated 10cm to the right from the floor to the waist height at the speed of about 25cm/sec. The EMG amplitudes on bilateral low back muscles (Longissimus, Iliocostalis, and Multifidus) are recorded during 2sec and analyzed. Independent variables are trunk postures (No bending vs. Bending to the LCG) and feet placements (Parallel vs. Right foot in front of the other vs. Right foot behind the other). Dependent variables are EMG amplitude average on six muscles and the EMG amplitude difference between right and left muscle group. Results indicate the phenomenon showing an amplitude increase in the left muscle group is equal to an decrease in the right one is observed in dynamic as well as static lifts, bending the trunk to the LCG increases amplitude discrepancy more than no trunk bending, and the amplitude discrepancy in one foot ipsilateral to LCG in front of the other foot is lowest among other foot postures. As bilateral EMG amplitude discrepancy increases total low back muscle fatigue, the strategical combination of no trunk bending and one foot close to LCG in front of the other is recommended for preventing elevated incidence of low back pain (LBP).

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.1
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• pp.111-119
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• 2005

This study presents continuous and discrete optimum design algorithm and computer programs for unbraced and braced steel frame structures under earthquake loads. The program, which is avaliable to perform structural analysis and optimum design, continuous and discrete, simultaneously is developed. And the program adopts various braced types, Untraced, Z-braced(V), Z-braced(inverse-V), X-braced(A), X-braced(B), X-braced(C) and K-braced, in steel structures with static loads and seismic effects. The objectives in this optimization are to minimize the total weight of steel, and design variables, based on the ultimate strength requirements of AISC-ASD specifications, the serviceability requirements and allowable story drift requirements of ATC-3-06, and various constraints. The purpose is to present proper braced type for seismic effects by comparing and analysing results of various cases.

• Korean Journal of Soil Science and Fertilizer
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• v.51 no.2
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• pp.79-89
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• 2018

Subsurface drip irrigation (SDI) system is considered one of the most effective methods for water application. A 2-year field study was conducted to investigate the effect of SDI systems with various dripline spacing (0.7 or 1.4 m) and position (under furrow or ridge) on soybean (Glycine max L.) production at a sandy-loam soil in Miryang, South Korea. For 2016-2017, average grain yield in SDI irrigated plots, $3.16Mg\;ha^{-1}$, was statistically greater than rainfed irrigated plot ($2.63Mg\;ha^{-1}$). Soybean grain yield averaged $3.25Mg\;ha^{-1}$ for the 0.7 m dripline spacing and $3.07Mg\;ha^{-1}$ for the 1.4 m spacing for the two-year period compared to a rainfed irrigated average of $2.63Mg\;ha^{-1}$ for the same period. Soybean treated with SDI system had significantly greater values of normalized difference vegetation index and stomatal conductance, indicating that soybean plants in SDI plots had greater photosynthetic and stomatal activity due to the higher water availability in soil. Irrigation water use efficiency (IWUE) was greatest in the plot of 0.7 m spacing installed under ridge position than any other plot across growing season. Average soil water content in plots with 0.7 m dripline spacing was $0.21m^3\;m^{-3}$ at 5 cm depth layer, which was 45% greater compared to the plots with 1.4 m spacing, even though the gross irrigation amounts were greater in 1.4 m spacing plots. It is concluded that wide dripline spacing (1.4 m) is probably the more economical installation design for SDI system compared to 0.7 m spacing in this study soil because the initial cost for dripline may be reduced with wide spacing design, even though the IWUE is greater in the plot of 0.7 m dripline spacing.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.1
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• pp.37-47
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• 2017

Purpose: This study aimed to explore the influences of attitude to death and resilience on terminal care attitude among Korean nursing students. Methods: Participants were 230 nursing undergraduates from two nursing schools in Korea. The students responded to a self-report questionnaire that included demographics, attitude to death, resilience, and terminal care attitude. Results: The majority of the participants who had undertaken a clinical practicum had experienced the death of a patient during their clinical placements but had not yet received any support from their instructors or professionals, but also academic training on patients' death or terminal care. The mean score of terminal care of the students who had death-related education was significantly higher than among those who had not. Regression analysis indicated that attitude to death, grade, and resilience were the most significant predictors of terminal care attitude. These explained 30.3% of their terminal care attitude. Conclusion: Death-related education is needed throughout the curriculum including not only death but also resilience to develop emotional competences. In this way, nursing undergraduates will be better prepared to cope positively and constructively with the suffering and death they encounter, and thus may minimize the distress they experience in the patients' dying process. It may also create a significant positive increase in their terminal care attitude.