• Journal of KIISE:Information Networking
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• v.31 no.1
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• pp.81-90
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• 2004

A Mobile Ad Hoc Network (MANET) is a collection of wireless mobile nodes dynamically self-organizing in arbitrary and temporary network topologies without the use of any existing network infrastructure. The AODV (Ad Hoc On-Demand Distance Vector) Protocol is one of the typical reactive routing protocols, in that mobile nodes initiate routing activities only in the presence of data packets in need of a route. In this paper, we focus upon the local repair mechanism of AODV. When a link is broken, the upstream node of the broken link repairs the route to the destination by initiating a local route discovery process. The process involves the flooding of AODV control messages in every node within a radius of the length from the initiating node to the destination. In this paper, we propose an efficient local repair scheme for AODV called AFLRS (AODV-based Fast Local Repair Scheme). AFLRS utilizes the existing routing information in the intermediate nodes which have been on the active route to the destination before a link break occurs. AFLRS can reduce the flooding range of AODV control messages and the route recovery time because it can repair route through the intermediate nodes. For the performance evaluation of the proposed AFLRS, we have simulated the local repair mechanisms by using NS2 and AODV-UU. The performance results show that AFLRS can achieve faster route recovery than the local repair mechanism of AODV.

• KIEAE Journal
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• v.12 no.5
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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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• v.27 no.4
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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.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.11
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• pp.30-36
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• 2010

In recent memories, repair is an unavoidable method to maintain its yield and quality. Although many word oriented memories as well as embedded memories in system-on-chip (SOC) consists of multiple local memory blocks with a global spare architecture, most of previous studies on built-in redundancy analysis (BIRA) algorithms have focused on single memory block with a local spare architecture. In this paper, a new BIRA algorithm for multiple blocks with a global spare architecture is proposed. The proposed BIRA is basd on CRESTA which is able to achieve optimal repair rate with almost zero analysis time. In the proposed BIRA, all repair solutions for local memory blocks are analyzed by local analyzers which belong to each local memory block and then compared sequentially and judged whether each solution can meet the limitation of the global spare architecture or not. Experimental results show that the proposed BIRA achieves much faster analysis speed compared to previous BIRAs with an optimal repair rate.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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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.

• Proceedings of the KSME Conference
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• 2008.11a
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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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• v.1 no.1
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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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• v.32 no.2
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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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• v.20 no.1
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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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• v.44 no.4
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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.