• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.25-26
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• 2019

The Reinforced concrete structure is deteriorated in durability due to various deterioration factors such as acid, salt, etc., and thus requires repair and reinforcement. In this study, compressive strength and weight change were measured by substituting blast furnace slag with excellent chemical resistance. As a result, the decrease in compressive strength decreased in proportion to the blast furnace slag substitution rate, and in the case of BFS40, the strength increased after sulfuric acid immersion. The weight change also decreased in proportion to the replacement amount.

• 응용통계연구
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• 제23권6호
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• pp.1147-1156
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• 2010

본 논문에서는 비 재생무료교체-수리보증이 종료된 이후의 수리가 가능한 시스템에 대한 교체정책을 제안한다. 이를 위해서, 비 재생무료교체-수리보증을 정의하고, 사용자 측면에서 비 재생무료교체-수리보증이 종료된 이후의 보전모형이 고려된다. 최적의 보전정책을 결정하기 위한 기준으로는 사용자 측면의 단위시간당 기대비용이 고려되고, 보증 기간이 종료된 이후에 발생되는 시스템의 유지비용은 사용자가 모두 지불하게 된다. 즉, 시스템의 운영기간 동안 사용자가 지불하여야 할 비용들이 주어져 있을 때, 비 재생무료교체-수리보증이 종료된 이후의 최적의 보전주기를 결정한다. 마지막으로 본 논문에서 제안된 보존정책을 설명하기 위해서 수치적 예를 살펴본다.

• 대한전자공학회논문지SD
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• 제47권11호
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• pp.30-36
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• 2010

최근의 메모리 반도체에 있어서, 수율과 품질을 유지하기 위하여 불량셀은 반드시 수리가 필요하다. 대부분의 워드단위 입출력을 갖는 system-on-chip (SoC)를 포함한 많은 메모리가 다중 블록으로 구성되어 있음에도 불구하고, 기존의 대부분의 자체내장수리연산회로의 연구들은 단일블록을 대상으로 하였다. 워드 단위 입출력 메모리의 특성상 다중메모리 광역대체수리구조를 갖는 경우가 많다. 본 논문에서는 이러한 메모리를 대상으로 기존에 최적 수리효율을 갖는 대표적인 자체내장 수리연산 회로인 CRESTA를 기본으로 하여, 보다 적은 면적으로 최적 수리효율을 낼 수 있는 알고리즘과 연산회로을 제안한다. 제안하는 자체내장수리 회로는 단위블록의 연산결과를 순차적으로 비교하여 워드단위 메모리의 제약조건을 만족시키는 최종 수리해를 구해내며, 기존의 회로보다 훨씬 빠른 시간 내에 최적의 수리 해를 구해 낼 수 있다.

• Archives of Plastic Surgery
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• 제33권3호
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• pp.308-312
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• 2006

Time to time, we face patients who missed the proper time for primary palatal repair. Although we do not have enough available documents, it is important to establish efficacy of palatal repair in patients more than 4 years old. From May 1995 to March 2005, we selected 14 patients who underwent palatal repair in more than 4 years old patients and they are able to tolerate speech articulation tests. Out of 14 patients 5 males an 9 females in sex, aged form 4 to 50 years old. 6 patients with incomplete cleft palate and 8 patients with submucous cleft palate. Double reversing Z-plasty(n=5), pushback palatoplasty(n=4), two flap palatoplasty(n=2), von Langenbeck palatoplasty(n=2), and intravelar veloplasty(n=1) were performed. Preoperative and postoperative speech articulation test, "Simple method of speech evaluation in Korean patients with cleft palate", were conducted. Satisfaction rate was sorted into 5 levels. There is no significant statistical correlation in the speech improvement, satisfaction rate, patients sex, cleft type and operative method. But there is significant statistical correlation between the speech improvement and patienet's age. There were better result in younger patient group than aged patients group.

• Archives of Plastic Surgery
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• 제40권6호
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• pp.721-727
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• 2013

Background One of the main concerns in orbital blowout fracture repair is a narrow operation field, due mainly to the innate complex three dimensions of the orbit; however, a deep location and extensive area of the fracture and soft tissue edema can also cause concern. Swelling of the orbital contents progresses as the operation continues. Mannitol has been used empirically in glaucoma, cerebral hemorrhage, and orbital compartment syndrome for decompression. The authors adopted mannitol for the control of intraorbital edema and pressure in orbital blowout fracture repair. Methods This prospective study included 108 consecutive patients who were treated for a pure blowout fracture from January 2007 to October 2012. For group I, mannitol was administered during the operation. Under general anesthesia, all patients underwent surgery by open reduction and insertion of an absorbable mesh implant. The authors compared postoperative complications, the reoperation rate, operation time, and surgical field improvement between the two groups. Results In patients who received intraoperative administration of mannitol, the reoperation rate and operation time were decreased; however, the difference was not statistically significant. The total postoperative complication rates did not differ. Panel assessment for the intraoperative surgical field video recordings showed significantly improved vision in group I. Conclusions For six years, mannitol proved itself an effective, reliable, and safe adjunctive drug in the repair of orbital blowout fractures. With its rapid onset and short duration of action, mannitol could be one of the best methods for obtaining a wider surgical field in blowout fracture defects.

• Clinics in Shoulder and Elbow
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• 제21권1호
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• pp.22-29
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• 2018

Background: This study is performed to evaluate anchor-related outcomes and complications after arthroscopic rotator cuff repair using 30% ${\beta}$-tricalcium phosphate (${\beta}$-TCP) with 70% poly lactic-co-glycolic acid (PLGA) biocomposite suture anchors. Methods: A total of 78 patients (mean age, $61.3{\pm}6.9years$) who underwent arthroscopic medium-to-large full-thickness rotator cuff tear repair were enrolled. The technique employed 30% ${\beta}$-TCP with 70% PLGA biocomposite suture anchors at the medial row (38 patients, Healix $BR^{TM}$ anchor [Healix group]; 40 patients, Fixone anchor B [Fixone group]). The radiologic outcomes (including perianchor cyst formation or bone substitution) and anatomical outcomes of the healing failure rate were evaluated using magnetic resonance imaging at least 6 months after surgery, the pain visual analogue scale at 3, 6 months, and final follow-up visit, and American Shoulder and Elbow Surgeons scores at least 1 year postoperatively. Anchor-related complications were also evaluated. Results: The perianchor cyst formation incidence was similar for both groups (60.5%, Healix group; 60.0%, Fixone group; p=0.967), although severe perianchor cyst incidence was slightly lower in the Fixone group (15.0%) than in the Healix group (21.1%). There was no occurrence of anchor absorption and bone substitution. No differences were observed in the healing failure rate (13.2%, Healix group; 15.0%, Fixone group; p=0.815) and functional outcome between groups (all p>0.05). Anchor breakage occurred in 5 patients (2 Healix anchors and 3 Fixone anchors); however, there were no major anchor-related complications in either group. Conclusions: No differences were observed in the clinical outcomes of the Healix and Fixone groups, neither were there any accompanying major anchor-related complications.

• 한국건설순환자원학회논문집
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• 제9권3호
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• pp.397-404
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• 2021

본 연구에서는 고상캡슐을 활용한 자기치유 표면보호재를 보수재료로 활용하기 위한 일환의 연구로써 고상캡슐이 표면보호재의 품질에 미치는 영향 및 장기재령의 치유 특성을 검토하였다. 고상캡슐 혼합에 따른 자기치유 표면보호재의 유변학적 특성 평가결과, 소성점도 및 항복응력, 테이블 플로우는 감소하는 경향이 나타났으며, 압축강도의 경우 고상캡슐 1%당 1 MPa이 비례적으로 감소하였다. 장기재령 치유특성을 평가한 결과, 재령 91일이 경과된 경우에도 고상캡슐이 보존되어 10% 혼합한 경우 치유재령 28일에 90% 수준의 치유율이 나타났으며, 치유재령 91일 경과후에는 고상캡슐 5%의 경우에도 90% 수준의 치유율이 나타났다.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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• pp.269-276
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• 1998

This paper proposes an opportunistic age replacement policy. The system has two types of failures. Type I failures (minor failures) are removed by minimal repairs, whereas type II failures are removed by replacements. Type I and type II failures are age-dependent. A system is replaced at type II failure (catastrophic failure) or at the opportunity after age T, whichever occurs first. The cost of the minimal repair of the system at age z depends on the random part C(z) and the deterministic part c(z). The opportunity arises according to a Poisson process, independent of failures of the component. The expected cost rate is obtained. The optimal $T^{\ast}$ which would minimize the cost rate is discussed. Various special cases are considered. Finally, a numerical example is given.

• Journal of the Korean Data and Information Science Society
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• 제14권2호
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• pp.393-403
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• 2003

In this paper, various replacement policies for the general failure model are considered. There are two types of failure in the general failure model. One is Type I failure (minor failure) which can be removed by a minimal repair and the other is Type II failure (catastrophic failure) which can be removed only by a complete repair. In this model, when the unit fails at its age t, Type I failure occurs with probability 1-p(t) and Type II failure occurs with probability p(t), $0{\leq}p(t){\leq}1$. Under the model, optimal replacement policies for the long-run average cost rate and the limiting efficiency are considered. Also taking the cost and the efficiency into consideration at the same time, the properties of the optimal policies under the Cost-Priority-Criterion and the Efficiency-Priority-Criterion are obtained.

• Management Science and Financial Engineering
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• 제7권2호
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• pp.73-90
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• 2001

This paper presents the reliability models for redundant systems composed of repairable components whose failure time and repair time distributions are phase-type. It is shown that the distribution of time to system failure is also phase-type. The dependency between components are considered and integrated into the model by the used of the rate adjustment factor. The phase-type representation is constructed for the system through algebraic operations on the parameters of components\` failure time and repair time distributions and the corresponding rate adjustment factors. Types of system structures considered are parallel, k-out-of-N system with load sharing scheme and standby system with operation priority.