• 한국정보과학회논문지:정보통신
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• 제31권1호
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• pp.81-90
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• 2004

모바일 애드 혹 네트워크 (MANET)는 무선 모바일 노드들이 하부구조(infrastructure)없이 동적으로 네트워크 토폴로지를 구성하는 것을 의미한다. AODV(Ad Hoc On-Demand Distance Vector) 프로토콜은 대표적인 요구기반 라우팅 프로토콜로서, 모바일 노드는 전송할 데이타가 있을 경우에만 라우팅 경로를 찾게 된다. 본 논문에서는 AODV의 지역 경로 복구 기법에 대해 다룬다 라우팅 링크가 단절되면 단절된 링크를 발견한 상위 노드는 목적지 노드까지의 라우팅 경로를 지역 경로 탐색과정을 통해 복구하게 된다. 이 과정에서 AODV 제어 메시지가 단절 경로의 상위노드로부터 목적지 노드까지를 반경으로 하는 지역에 퍼지게 된다. 본 논문에서는 AFLRS(AODV-based Fast Local Repair Scheme)이라고 하는 AODV를 위한 효율적인 지역 경로 복구 기법을 제안한다. AFLRS는 경로 단절이 일어나기 전에 라우팅 노드들이 유지하고 있던 라우팅 정보를 이용하므로 AODV 제어 메시지의 플러딩 범위를 줄이고 경로 복구 시간을 줄일 수 있다. 제안된 AFLRS의 성능평가를 위해 지역경로 기법들을 NS2와 AODV-UU 시뮬레이터를 이용하여 시뮬레이션 하였으며 실험결과에서 AFLRS가 AODV에서의 경로복구기법 보다 빠르게 경로 복구를 할 수 있음을 보인다.

• KIEAE Journal
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• 제12권5호
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• pp.29-34
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• 2012

A rental housing has a key role to supply the living space to non-ownership. A public rental housing is particularly aimed at providing the living space for the low-income households with a low rent fee. Therefore, the local government would try to maintain the facilities of the rental housing and to get the decent living condition. For getting the required living condition, it should make a maintenance plan, which contains the repair time, repair scope and targeted component and finishings. This study is aimed at providing the optimal repair time in 12 components and components of the rental housing which is controlled by the local government. The optimal repair time has two steps to get the final result. First, it would draw the 1'st repair time with the probabilistic and empirical approach. Second, comparing the drawn data and the service life, the optima repair time would be provided with considering the components' attributes. Result are as follows : First, the optimal repair time would be considered with the component attributes. There are user's convenience, its safety and physical aspect. Second, the kitchen utensils, elevator and water tap has a optimal time of 16, 19, 17 years respectively which is considered with physical aspect. In addition, the optima repair time of the wiring appliance and lighting equipment are 12 years and 10 years respectively.

• Journal of Trauma and Injury
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• 제27권4호
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• pp.178-185
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• 2014

Purpose: The aim of this study was to assess the clinical efficacy of combined treatment with local anesthesia and ketamine procedural sedation for pediatric facial laceration repair in the Emergency Department (ED). Methods: Patients aged 1 to 5 years receiving ketamine for facial laceration repair were prospectively enrolled in a double-blind, randomized, and controlled study at an ED. All patients were to receive intravenous ketamine (2 mg/kg). The local anesthesia group (LA group) received a local anesthetic along with ketamine, whereas the no local anesthesia group (NLA group) received only ketamine. The total time of sedation, the patients' movements and groans, adverse events, and the satisfaction ratings of physicians, nurses, and parents were recorded. Results: A total of 186 patients were randomized (NLA group: 90, LA group: 96). The total time of sedation (30.5 minutes for the NLA group, 32.6 minutes for the LA group; p=0.660), patients' groans (26 (28.9%) versus 23 (24.0%); 0.446) and movements (27 (30%) versus 35 (36.5%); p=0.350) was not affected by the addition of local anesthesia. Other adverse events were similar between the two groups. Also, the satisfaction ratings of physicians (median 4 for the NLA group versus 4 for the LA group (p=0.796)), nurses (2 versus 2.5 (p=0.400)), and parents (4 versus 4 (p=0.199)) were equivalent between the two groups. Conclusion: In this study, we found that local anesthesia was not required along with ketamine sedation for pediatric facial laceration repair.

• 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.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2003년도 가을 학술발표논문집 Vol.30 No.2 (3)
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• pp.400-402
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• 2003

Ad­hoc Network는 Mobile Node들 간에 Multi­hop 무선 링크로 구성되는 Network을 일컫는 말이며, 동시에 Network를 통제하는 Infrastructure없이 Node들 간의 상호 통신에 의해서 Network이 구성되기도 하고, Node들이 이동하거나 환경적인 장애에 의해서 일시적으로 Network이 구성되지 않기도 한다. 이 논문에서는 대표적인 On­demand Routing Algorithm인 DSR를 이용하여, 두 개의 경로를 유지하여 Primary Path에 문제가 발생하는 경우, Secondary Path가 Primary Path로 전환되어 Data를 전송하고, 이 전 Primary Path에 대하여 지역적으로 복구(Repair)를 수행하고, 설정된 Secondary Path에 대해서도 특정한 조건에서 복구작업을 수행함으로써 Ad­hoc Network에서 경로를 찾고 설정하는데 필요한 Routing Overhead를 줄이고 Ad­hoc Network의 특성상 반드시 보완하여야 하는 전송 Route에 대한 Robustness를 강화하는 방법이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.132-137
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• 2008

A failure analysis of ammonia converter which suffered hydrogen attack in two years since its initial operating time was presented. It is constructed from 2.25 Cr.1 Mo steel. Analysis showed that the failure on closing seam weld joint was due to local improper post weld heat treatment (PWHT). Improper PWHT can introduce high residual stresses in thick-walled pressure vessel. High residual stress level in weld joint is very prone to hydrogen attack for any components which are operating in hydrogen gas environment. The repair procedures based on the principle to decrease the residual stress then proposed. The repair was controlled very carefully by applying several nondestructive tests in the each stage of repair. To assure the successful of the proposed repair, after one year since repair time, high temperature ultrasonic and TOFD methods were applied on-stream to this equipment in order to evaluate its post repair condition. The two methods showed good results on the repaired area.

• Journal of Ubiquitous Convergence Technology
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• 제1권1호
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• pp.28-34
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• 2007

Tree-based reliable multicast protocols provide scalability by distributing error-recovery tasks among several repair nodes. These repair nodes perform local error recovery for their receiver nodes using the data stored in their buffers. We propose a packet loss patterns adaptive feedback scheduling scheme to manage these buffers in an efficient manner. Under our scheme, receiver nodes send NAKs to repair nodes to request packet retransmissions only when the packet losses are independent events from other nodes. At dynamic and infrequent intervals, they also send ACKs to indicate which packets can be safely discarded from the repair node's buffer. Our scheme reduces delay in error recovery because the requested packets are almost always available in the repair node's buffers. It also reduces the repair node's workload because (a) each receiver node sends infrequent ACKs with non-fixed intervals and (b) their sending times are fairly distributed among all the receiver nodes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권2호
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• pp.117-128
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• 2006

Free flap transplantation with microvascular anastomosis has been successfully performed by development of surgical technique, materials and postoperative monitoring equipments of flap. But success rate of microvascular anastomosis is influenced by various factors, and failure rate is about 5-10%. The most influential factor for success rate is surgical technique and other factors that influence failure of microvascular anastomosis are ischemic time of free flap, thrombus formation of anastomosis region and vascular spasm. Many studies has been published in microvascular anastomosis with histologic effect for irrigating solution. But local irrigation solution has been used clinically in microvascular anastomosis, the comparison with each solution, microhistological study for endothelial cell repair and vascular patency has not been reported. The heparin which is anti-thrombotic agent, and urokinase which is fibrinolytic agent are used for this study. Vascular patency and thrombus formation in experimental micro-arterial anastomosis, and endothelial repair were observed with histologic analysis, scanning electron microscopy, transmission electron microscopic examination. The results were obtained as follows: 1. In vascular patency test in 30 minute and 7 days after micro-arterial anastomosis, equal effects of good vascular patency were obtained in group of local irrigation with heparin and urokinase. 2. In thrombus formation in 7 days after micro-arterial anastomosis, equal effects of minimal thrombus formation were obtained in group of local irrigation with heparin and urokinase. 3. In toluidin blue staining in 7 days after micro-arterial anastomosis, local destruction of endothelial cell and inner elastic lamina were seen and endothelial repair was not seen. 4. In scanning electron microscope examination in 7 days after micro-arterial anastomosis, endothelial cell was not seen in peripheral to suture materials, thrombus associated fibrin network was observed. 5. In transmission electron microscope examination in 7 days after micro-arterial anastomosis, inflammatory cell was seen within smooth muscle cells in site of endothelial cell destruction, smooth muscle cell around suture material were arranged irregularly, some collagenous change were seen. From the results obtained in this study, same results of good vascular patency and anti-thrombotic effect of heparin and urokinase were obtained as a local irrigation solution, and repair of endothelial cell was not seen in 7 days after micro-arterial anastomosis.

• Advances in pediatric surgery
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• 제20권1호
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• pp.7-11
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• 2014

The present study compared the postoperative analgesic effects of ilioinguinal and iliohypogastric nerve block with infiltration of local anesthetics (bupivacaine) into the wound in children after inguinal hernia repair. Ninety children below 7 years old who were scheduled elective inguinal hernia repair were randomly allocated into one of three groups. The patients in nerve block (NB) group, ilioinguinal and iliohypogastric nerve block was done with 0.5 mL/kg of 0.25% bupivacaine. The patients in infiltration of local anesthetics (LI) group, 0.5 mL/kg of 0.25% bupivacaine was infiltrated into the wound after surgery. The patients in control group were allocated as a Control group. Postoperative pain was assessed at 1, 3, 5, and 24 hours after operation with FLACC scale and additional analgesic consumption were counted. The three groups were not significantly different in age, sex, body weight, and duration of operation. Pain scores at 1 hour and 3 hours after operation were significantly higher in Control group than in NB group and LI group (p<0.01), whereas there were no difference between NB group and LI group. The rescue analgesics administration was significantly higher in Control group (n=11) than in NB group (n=6) and LI group (n=7) (p<0.05). There were 2 cases of transient femoral nerve palsy in NB group. Both of ilioinguinal and iliohypogastric nerve block and infiltration of local anesthetics into the wound provided effective postoperative analgesia in early postoperative period following inguinal hernia repair in children. But no difference between the two methods. Technically, infiltration of local anesthetics into the wound was easier and safer than ilioinguinal and iliohypogastric nerve block.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제44권4호
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• pp.159-166
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• 2018

Objectives: The aim of the study was to compare wound healing complications following the use of either absorbable or non-absorbable sutures for skin closure in cleft lip repair. Materials and Methods: This was a randomized controlled trial conducted at the Department of Oral and Maxillofacial Surgery, Lagos University Teaching Hospital, Idi Araba, Lagos State, Nigeria. Sixty subjects who required either primary or secondary cleft lip repair and satisfied all the inclusion criteria were recruited and randomized into two groups (Vicryl group or Nylon group). The surgical wounds in all subjects were examined on 3rd, 7th, and 14th postoperative days (POD) for presence or absence of tissue reactivity, wound dehiscence, and local wound infection. Results: Hemorrhage, tissue reactivity, wound dehiscence, and local wound infection were identified as wound healing complications following cleft lip repair. The incidence of postoperative wound healing complications on POD3 was 33.3%. Tissue reactivity was more common throughout the evaluation period with the use of an absorbable (Vicryl) suture compared to a non-absorbable (Nylon) suture, although the difference was statistically significant only on POD7 (P=0.002). There were no significant differences in the incidences of wound dehiscence and infection between the two groups throughout the observation period. Conclusion: There were no statistically significant differences in the incidences of wound dehiscence and surgical site wound infection following the use of either Vicryl or Nylon for skin closure during cleft lip repair. However, more cases of tissue reactivity were recorded in the Vicryl group than in the Nylon group on POD7. Particular attention must be paid to detect the occurrence of wound healing complications, most especially tissue reactivity, whenever a Vicryl suture is used for skin closure in cleft lip repair.