• Title/Summary/Keyword: Rigid method

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Paradox of Meritocracy of the Social Welfare Organization in the Neoliberalism (사회복지 실천현장의 신자유주의적 성과주의 역설: 사회복지사의 경험을 중심으로)

  • Lee, In Sook
    • 한국사회정책
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    • v.24 no.1
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    • pp.239-275
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    • 2017
  • The purpose of this study is to explore what social workers experience and how they experience the needs of Meritocracy in the social welfare organization in the neoliberalism.. Therefore, in-depth interviews were conducted with 18 social workers, and I analyzed Colaizzi(1978) in a phenomenological method through collected research materials. As a result, the analysis is integrated in a total of four essential themes. According to the research results, the meritocracy - oriented phenomenon in the social welfare organization was 'paradox of Meritocracy'. Participants were buried in creating "nominal performance without any effectiveness" based on effectiveness and efficiency. Clients were instrumentalized in performance; moreover, they lost contact points with the field. Above all, there was "a reorganization of practices" that contradicted the original values of practice, in which the quality deterioration of service and the connection between organizations were weakened. In addition, the implementation of accountability of social welfare organization, which was intended by Meritocracy, has become a criterion for external evaluation, and the challenge of uncertain result has left a "rigid accountability without discretion." While participants were devoted to making a nominal performance, they failed to be guaranteed by the distinct characteristics of social welfare group. They experienced lost pride of the practitioner in the reality which contained the value of social welfare. However, in spite of this paradox of Meritocracy, participants demonstrated flexibility in order to preserve the original value and reached "a compromise with reality in the identity conflict." Based on the results of the research, I presented the discussion and policy directions.

Current Trends in the Treatment of Syndesmotic Injury: Analysis of the Korean Foot and Ankle Society (KFAS) Member Survey (원위경비골인대 손상의 치료 동향: 대한족부족관절학회 회원 설문조사 분석)

  • Cho, Jaeho;Cho, Byung-Ki;Jeong, Bi O;Chung, Jin-Wha;Bae, Su-Young;The Academic Committee of Korean Foot and Ankle Society,
    • Journal of Korean Foot and Ankle Society
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    • v.26 no.2
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    • pp.95-102
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    • 2022
  • Purpose: This study was based on the Korean Foot and Ankle Society (KFAS) member survey and aimed to report the current trends in the management of syndesmotic injuries over the last few decades. Materials and Methods: A web-based questionnaire containing 36 questions was sent to all KFAS members in September 2021. The questions were mainly related to the preferred techniques and clinical experiences in the treatment of patients with syndesmotic injuries. Answers with a prevalence ≥50% of respondents were considered a tendency. Results: Seventy-six (13.8%) of the 550 members responded to the survey. The results showed that the most preferred method to diagnose a syndesmotic injury was magnetic resonance imaging (MRI). Intraoperatively, the external rotation stress test and the Cotton test were most frequently used to confirm syndesmotic diastasis. The reduction was usually done by a reduction clamp. One 3.5-mm screw was used most frequently over three cortices at 2~4 cm above the ankle joint. The preferred ankle position during fixation was 0° dorsiflexion. Removal of the syndesmotic screw was routinely done by most surgeons, mainly because of the limitation of movement and risk of screw breakage. Factors that affect suture button selection included non-rigid fixation which enables adequate fixation, early weight-bearing, and an infrequent need to remove the hardware. Inadequate reduction was considered the main factor that affects poor prognosis. Conclusion: This study proposes updated information about the current trends in the management of syndesmotic injuries in Korea. Consensuses in both the diagnostic and therapeutic approach to patients with syndesmotic injury were identified in this survey study. This study may raise the awareness of the various possible approaches toward the injury and should be used to further establish a standard protocol for the management of syndesmotic injuries.

Variation of Earth Pressure Acting on the Cut-and-Cover Tunnel Lining due to Geotextile Mat Reinforcement (지오텍스타일 매트의 설치에 의한 개착식 터널 라이닝에 작용하는 토압의 변화)

  • Bautista, F.E.;Park, Lee-Keun;Im, Jong-Chul;Joo, In-Gon
    • Journal of the Korean Geotechnical Society
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    • v.23 no.3
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    • pp.25-40
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    • 2007
  • Excessive earth pressure is one of the major mechanical factors in the deformation and damage of Cut-and-Cover Tunnel lining in shallow tunnels and portals of mountain tunnels (Kim, 2000). Excessive earth pressure may be attributed to insufficient compaction and consolidation of backfill material due to self-weight, precipitation and vibration caused by traffic (Komiya et al., 2000; Taylor et al., 1984; Yoo, 1997). Even though there were a lot of tests performed to determine the earth pressure acting on the tunnel lining, unfortunately there were almost no case histories of studies performed to determine remedial measures that reduce differential settlement and excessive earth pressure. In this study the installation of geotextile mat was selected to reduce the differential settlement and excessive earth pressure acting on the cut-and-cover tunnel lining. In order to determine settlement and earth pressure reduction effect (reinforcement effect) of geotextile mat reinforcement, laboratory tunnel model tests were performed. This study was limited to the modeling of rigid circular cut-and-cover tunnel constructed at a depth of $1.0D\sim1.5D$ in loose sandy ground and subjected to a vibration frequency of 100 Hz. Model tests with varying soil cover, mat reinforcement scheme and slope roughness were performed to determine the most effective mat reinforcement scheme. Slope roughness was adjusted by attaching sandpaper #100, #400 and acetate on the cut slope surface. Mat reinforcement effect of each mat reinforcement scheme were presented by the comparison of earth pressure obtained from the unreinforced and mat reinforced model tests. Soil settlement reduction was analyzed and presented using the Picture Analysis Method (Park, 2003).

Variation of Earth Pressure Acting on Cut-and-Cover Tunnel Lining with Settlement of Backfill (되메움토의 침하에 따른 개착식 터널 라이닝에 작용하는 토압의 변화)

  • Bautista F.E.;Park Lee-Keun;Im Jong-Chul;Lee Young-Nam
    • Journal of the Korean Geotechnical Society
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    • v.22 no.6
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    • pp.27-40
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    • 2006
  • Damage of cut-and-cover tunnel lining can be attributed to physical and mechanical factors. Physical factors include material property, reinforcement corrosion, etc. while mechanical factors include underground water pressure, vehicle loads, etc. This study is limited to the modeling of rigid circular cut and cover tunnel constructed at a depth of $1.0{\sim}1.5D$ in loose sandy ground and subjected to a vibration frequency of 100 Hz. In this study, only damages due to mechanical factors in the form of additional loads were considered. Among the different types of additional, excessive earth pressure acting on the cut-and-cover tunnel lining is considered as one of the major factors that induce deformation and damage of tunnels after the construction is completed. Excessive earth pressure may be attributed to insufficient compaction, consolidation due to self-weight of backfill soil, precipitation and vibration caused by traffic. Laboratory tunnel model tests were performed in order to determine the earth pressure acting on the tunnel lining and to investigate the applicability of existing earth pressure formulas. Based on the difference in the monitored and computed earth pressure, a factor of safety was recommended. Soil deformation mechanism around the tunnel was also presented using the picture analysis method.

Preparation of Silica Nanoparticles via Recycling of Silicon Sludge from Semiconductor Dicing Process and Electro-responsive Smart Fluid Application (반도체 다이싱 공정에서 발생하는 실리콘 슬러지를 재활용한 실리카 나노입자의 제조 및 전기감응형 유체로의 응용)

  • Yeon-Ryong Chu;Suk Jekal;Jiwon Kim;Ha-Yeong Kim;Chan-Gyo Kim;Minki Sa;Hyung Sub Sim;Chang-Min Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.3
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    • pp.15-25
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    • 2023
  • In this study, silicon sludge from semiconductor dicing process is recycled to fabricate silica nanoparticles, which are applied as dispersing materials for electro-responsive (ER) smart fluid. In specific, metal impurities are removed from silicon sludge by acid washing to obtain the high-purity silicon powder. And then, silica nanoparticles are synthesized by facile hydrothermal method employing the silicon powder as reactant material. To control the size of silica nanoparticles, the reaction time of hydrothermal method is varied as 8, 15, 20, and 30 hours are applied to control the size of silica nanoparticles. Sizes of silica nanoparticles are increased proportionally to the reaction time owing to the increased numbers of hydrolysis and condensation reactions. As-synthesized silica nanoparticles are prepared as electro-responsive smart fluids by dispersing into silicon oil. Silica nanoparticles synthesized by 30 hours of hydrothermal reaction (SiO2-H30) exhibit the highest shear stress of 21.4 Pa under an applied electric field strength of 3.0kV mm-1. Such enhancement in ER performance of SiO2-H30 among various silica nanoparticles are attribute to the reinforcing effect originated from the mixed particle size, which allowing the formation of rigid chain-like structures. Accordingly, this study successfully propose a recycling method of silicon sludge to synthesize silica nanoparticles and their derived ER fluids, which may suggest new possibility to ESG management emphasizing the eco-friendliness.

A Review on Ultimate Lateral Capacity Prediction of Rigid Drilled Shafts Installed in Sand (사질토에 설치된 강성현장타설말뚝의 극한수평지지력 예측에 관한 재고)

  • Cho Nam Jun;Kulhawy F.H
    • Journal of the Korean Geotechnical Society
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    • v.21 no.2
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    • pp.113-120
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    • 2005
  • An understanding of soil-structure interaction is the key to rational and economical design for laterally loaded drilled shafts. It is very difficult to formulate the ultimate lateral capacity into a general equation because of the inherent soil nonlincarity, nonhomogeneity, and complexity enhanced by the three dimensional and asymmetric nature of the problem though extensive research works on the behavior of deep foundations subjected to lateral loads have been conducted for several decades. This study reviews the four most well known methods (i.e., Reese, Broms, Hansen, and Davidson) among many design methods according to the specific site conditions, the drilled shaft geometric characteristics (D/B ratios), and the loading conditions. And the hyperbolic lateral capacities (H$_h$) interpreted by the hyperbolic transformation of the load-displacement curves obtained from model tests carried out as a part of this research have been compared with the ultimate lateral capacities (Hu) predicted by the four methods. The H$_u$ / H$_h$ ratios from Reese's and Hansen's methods are 0.966 and 1.015, respectively, which shows both the two methods yield results very close to the test results. Whereas the H$_u$ predicted by Davidson's method is larger than H$_h$ by about $30\%$, the C.0.V. of the predicted lateral capacities by Davidson is the smallest among the four. Broms' method, the simplest among the few methods, gives H$_u$ / H$_h$ : 0.896, which estimates the ultimate lateral capacity smaller than the others because some other resisting sources against lateral loading are neglected in this method. But it results in one of the most reliable methods with the smallest S.D. in predicting the ultimate lateral capacity. Conclusively, none of the four can be superior to the others in a sense of the accuracy of predicting the ultimate lateral capacity. Also, regardless of how sophisticated or complicated the calculating procedures are, the reliability in the lateral capacity predictions seems to be a different issue.

CLINICAL CHARACTERISTICS AND TREATMENT COURSES OF THE CHILDREN WITH SELECTIVE MUTISM (선택적 함구증 아동의 임상특성 및 치료경과)

  • Chung, Sun-Ju;Hong, Kang-E
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.74-89
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    • 1995
  • Selective mutism is a childhood condition defined by persisten failure to speak in specific social situation when speaking is expected, dispite preserved ability to comprehend spoken language and speak. Present study is to investigate clinical characteristics, treatment method and outcome of 23 children who were diagnosed as selective mutism by DSM-IV criteria at the child psychiatry ouptatient department of SNUH. The results were as follows : 1) The Sex ratio was 1: 4.8, female dominant Mear age of onset was 33 years old and mean age of first referral was 7.7 years old. 2) 22% of subjects had perinatal problem such as low birth weight, preterm birth, 26% of the subjects have history of delayed language development. There are subjects who had been separated with mam caretaker before 3 years old(26%) and who experienced physical or psychological trauma before 3 years old(26%). A few subjects had enurests(30%) and encoprests(4%). 3) Many subjects(65%) had symbiotic relationship with their mother. These families consist of dominant, verbally aggressive mother and passive father. Parents of 39% of all subjects were judged to have definite psychopathology(social phobic, depression, hysterical trait or alcohol problem) 26% of all subject, were reported physically abused. 4) The personality trait of the subjects were frequently described as follows(in order of frequency) ; Shy(100%), anxious(83%), stubborn(83%)m rigid and tense posture(78%), immature(65%) overdependent(65%), irritable(52%), manipulative(39%), depressive(39%). 5) The mean performance IQ of 16 subjects by KEDI-WISC was 88.3 Among them, the subjects with IQ below 69 were seven and those with IQ above 70 were nine. When comparing these two group(Mental retardation group vs Normal IQ group), we could find some difference in language development, personality trait, family dynamics and treatment outcome. 6) Among several treatment methods for selective mutism, play therapy was the most frequently used method(65%). Other commonly used treatment methods were pharmacotherapy(21%), behavioral therapy(8%), combined therapy(play therapy+pharmacotherapy+family therapy+behavioral therapy)(12%), 7) Regarding the outcome of treatment 8.6% was evaluated as Excellent, 30.4% as Good, 52% as Fair, 8.7% as Poor at the tinic of treatment. At follow up interview 21.7% was evaluated Excellent, 13% as Good, 21.7% as Fair, 34.8% as Poor. 8) We classified all subjects by Havden's 4 subtype. Symbiotic mutism was most common(65%) and other subtypes are Speech phobic mutism(8.6), Reactive mutism(13%) and Passive-aggressive mutism(30%).

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Experimental Study on the Performance Improvement of Velcro Reinforcement through Internal Filling (내부충진을 통한 벨크로 보강재의 성능향상에 대한 실험적 연구)

  • Jeong, Yeong-Seok;Kwon, Minho;Kim, Jin-Sup;Nam, Gwang-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.41 no.4
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    • pp.347-355
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    • 2021
  • During the earthquake, for multi-story structure, if the first floor is soft, the deformation will concentrate on that floor causing a serious damage to the column members which might leads to the collapse of the whole structure like Piloti structure during the Pohang earthquake in Korea. According to the 2016 National Disaster Management Research Institute's "Investigation of Seismic Reinforcement and Cost Analysis of Domestic Non-seismic Buildings", the rate of seismic resistance of private reinforced concrete buildings was 38.3 %. Among them, it was reported that the seismic-resistance ratio of the two to five-story structures was less than 50 %. Accordingly, the government is trying to improve the seismic rate through support projects, but the conventional seismic reinforcement methods are still expensive, and emergency construction is difficult. Therefore, in this study, the field applicability was evaluated by improving the reinforcement method using Velcro, which was developed through the research project of the Ministry of Land, Transport and Maritime Affairs in 2014. In order to improve the performance of the Velcro reinforcement method, introducing the initial tension of Velcro using high foaming rigid urethane filling between the Velcro and concrete of the columns was applied. Additionally, an experiment was conducted to evaluate the ductility of Velcro specimen from the concrete confinement effect. As a result, the ductility of the Velcro specimen was improved compare to Normal specimen. However, the energy dissipation capacity of VELCRO2 is better than VELCRO1, yet the maximum ductility of those two specimens did not show a significant difference. Therefore, the improvement of the internal filler material is still needed to have a better maximum ductility.

Analysis on dynamic numerical model of subsea railway tunnel considering various ground and seismic conditions (다양한 지반 및 지진하중 조건을 고려한 해저철도 터널의 동적 수치모델 분석)

  • Changwon Kwak;Jeongjun Park;Mintaek Yoo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.6
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    • pp.583-603
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    • 2023
  • Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

Limited Open Reduction and Internal Fixation of the Tibial Pilon Fractures (제한 절개를 통한 관혈적 정복 및 내고정술을 이용한 경골 Pilon 골절의 치료)

  • Kang, Chung-Nam;Kim, Jong-Oh;Kim, Dong-Wook;Koh, Young-Do;Ko, Sang-Hun;Yoo, Jae-Doo;Hwang, Jun-Ho
    • Journal of Korean Foot and Ankle Society
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    • v.1 no.2
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    • pp.102-111
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    • 1997
  • The tibial Pilon fracture, which is defined as a comminuted intraarticular fracture of the distal tibia, is difficult to manage because high axial compression and rotational forces to the ankle joint result in impaction, severe comminution, metaphyseal disruption and soft tissue damage. There are variable methods of treatment such as manipulation and cast, calcaneal traction and cast, external fixation, pin and plaster, limited open reduction and external fixation, and open reduction and rigid internal fixation. Though most of authors reported better result after a surgical treatment. than that of conservative treatment, many complications such as posttraumatic arthritis and soft tissue problem still remain troublesome. We have reviewed 19 cases of the tibial Pilon fractures in 18 patients which were treated with limited open reduction and internal fixation from September 1993 to May 1996. The results were as follows: 1. The fractures were classified into five types according to the system of Ovadia and Beals, and the most frequent type was type 3 (53%). The most common cause of injury was traffic accident (47%). 2. All of the cases of type 1 and 2, in which the injury of the ankle joint was less severe, revealed good or excellent clinical results. But in type 4 and 5, because the injury is much severe and accurate reduction is difficult, the clinical results were unsatisfaetory. 3. The most frequent complication was posttraumatic osteoarthritis, and which developed in second frequent complication, was developed m the three cases of type 3 in which the radiographic results were less than fair, but there were no correlation with the clinical results. 4. We could markedly reduce the complications related to the soft tissue problem of Pilon fracture by treatment with limited open reduction and internal fixation, and consider that this is a good method of treatment of Pilon fracture when the injury is less severe and accurate reduction is possible.

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