• Archives of Reconstructive Microsurgery
• /
• v.14 no.2
• /
• pp.131-137
• /
• 2005

The extensor digitorum brevis (EDB) muscle island flap is a reliable, safe method for coverage of foot and ankle. There are many variation in approach such as curvilinear, zigzag, L-shaped or vertical longitudinal incision for exposure of the EDB muscle. These approaches use only single incision excluding the distal incision for exposure of the distal tendon. Since dorsalis pedis artery vascular bundle and sinus tarsi branch of the lateral tarsal artery both requires careful dissection, single incision alone may cause not only difficulty in exposure but also skin sloughing at donor site. So we tried to modify the approach into two parallel longitudinal incision, one for dorsalis pedis vascular bundle and the other for sinus tarsi branch exposure. The author treated 9 patient with EDB muscle flap. We used single incision in six patients, and two parallel incision in three patients. All the flap survived. In two parallel incision group, dissection was more easy and rapid. So we would like to suggest that two parallel longitudinal incision approach is better method than the single incision technique for exposure of the EDB muscle flap.

• Journal of Korean Neurosurgical Society
• /
• v.65 no.1
• /
• pp.40-48
• /
• 2022

Objective : Placement of a single transverse stent via the nondominant A1 across the anterior communicating artery (AComA) into the contralateral A2 can provide sufficient neck coverage for wide-necked bifurcation AComA aneurysms. The authors described the feasibility, safety and long-term outcomes of this technique. Methods : Between January 2015 and February 2018, placement of a single transverse stent via the nondominant A1 was attempted in 17 wide-necked bifurcation AComA aneurysms. The authors reviewed the medical records and radiological studies. Results : The technical success rate was 94.1% (16/17). Periprocedural thromboembolic complications occurred in one patient (6.3%) without permanent neurological deficits. The mean clinical follow-up duration was 39.9±9.8 months. No deaths or delayed thromboembolic complications occurred. The mean angiographic follow-up duration was 38.9±9.8 months. The immediate and final follow-up complete occlusion rates were 87.4 and 93.7%, respectively. There was no recanalization during the follow-up period. Conclusion : Placement of a single transverse stent via the nondominant A1 across the AComA into the contralateral A2 is a feasible and relatively safe endovascular technique for the treatment of wide-necked bifurcation AComA aneurysms, with good long-term occlusion rates and a reasonable complication rate, if only the nondominant A1 is applicable.

• Genomics & Informatics
• /
• v.20 no.3
• /
• pp.34.1-34.11
• /
• 2022

Multilevel analysis is an appropriate and powerful tool for analyzing hierarchical structure data widely applied from public health to genomic data. In practice, however, we may lose the information on multiple nesting levels in the multilevel analysis since data may fail to capture all levels of hierarchy, or the top or intermediate levels of hierarchy are ignored in the analysis. In this study, we consider a multilevel linear mixed effect model (LMM) with single imputation that can involve all data hierarchy levels in the presence of missing top or intermediate-level clusters. We evaluate and compare the performance of a multilevel LMM with single imputation with other models ignoring the data hierarchy or missing intermediate-level clusters. To this end, we applied a multilevel LMM with single imputation and other models to hierarchically structured cohort data with some intermediate levels missing and to simulated data with various cluster sizes and missing rates of intermediate-level clusters. A thorough simulation study demonstrated that an LMM with single imputation estimates fixed coefficients and variance components of a multilevel model more accurately than other models ignoring data hierarchy or missing clusters in terms of mean squared error and coverage probability. In particular, when models ignoring data hierarchy or missing clusters were applied, the variance components of random effects were overestimated. We observed similar results from the analysis of hierarchically structured cohort data.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.11
• /
• pp.3086-3096
• /
• 1999

To declare conformance of multi-protocol Implementation Under Test(IUT), every layer of the multi-protocol IUT should be tested. According to ISO9646, single-layer test method is applied to testing the highest layer of multi-protocol IUT and single-layer embedded test method is used for the layers by layer all the protocols in a multi-protocol IUT. This paper proposes a new method for testing a multi-protocol IUT. The proposed test method assumes that a multi-protocol IUT is under test and that the interfaces between the layers cannot be controlled or observed by the tester. We apply the proposed test method to TCP/IP and compare the application results with those of the existing test turns out that the proposed test method significantly reduces the number of test cases as well as the number of test events while providing the same test coverage. In addition, the proposed test method shows the capability to locate the layer that is source of failure in testing multi-protocol IUTs.

• Journal of the Korean Ceramic Society
• /
• v.44 no.3 s.298
• /
• pp.142-146
• /
• 2007

High-quality one-dimensional GaN nanorods and nanowires were synthesized on Ni-coated c-plan sapphire substrate using halide vapor-phase epitaxy (HVPE). Their structure and optical properties were investigated by X-ray diffraction, scanning and transmission electron microscopy, and photoluminescence techniques. Full substrate coverage of densely packed, uniform, straight and aligned one-dimensional GaN nanowires with a diameter of 80nm were grown at $700{\sim}900^{\circ}C$. The X-ray diffraction patterns, transmission electron microscopic image, and selective area electron diffraction patterns indicate that the one-dimensional GaN nanostructures are a pure single crystalline and preferentially oriented in the [001] direction. We observed high optical quality of GaN nanowires by photoluminescence analysis.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.151-152
• /
• 2006

Multi-hop system has advantage of low power consumption, improved cell capacity, and enlarged service coverage. Most of previous researches show that multi-hop relaying beyond dual-hop relaying does not improve system performance significantly. This leads most researches are focused on dual-hop relaying system. In this paper, we propose an optimal boundary condition to support maximal data rate for fluctuation of traffic load in single cell dual-hop relay system.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.183-183
• /
• 2017

In the early part of rice growth, root volume primarily limits the amount of plant-accessible nitrogen (N). Therefore, knowledge of the root development is important for modeling N uptake of rice. The timing when the volume of rhizosphere cover the whole soil is also important to carry out timely top dressing. However, information about initial root expansion and associated N uptake is limited due to intrinsic technical difficulties in assessing below-ground processes. Some studies, however, showed a close relationship between below-ground root and above-ground leaf development, suggesting a possibility that above-ground attributes could serve as surrogates for the root processes. In this study, we investigated the relationship between below-ground and above-ground development of rice. Field experiments were conducted where we cultivated Koshihikari (a leading cultivar in Japan) for four different cropping schedules in 2012. In 2016, Gimbozu (HEG4) and three flowering time mutant lines of Gimbozu (X61 (se13), HS276 (ef7), DMG9 (se13, ef7)) were examined for a single season. Experiments were performed with three replications in a completely randomized design. We monitored ammonium-N concentration ([NH4+-N]) in soil solution by repeatedly taking samples from a porous tubing (10-cm long) vertically inserted at the most distant point from surrounding rice hills. Samples were taken in triplicate (= triplicate tubes) and every three days from transplanting in each experimental unit. For above-ground attributes, leaf area index (LAI) was measured in 2012, whereas soil coverage ratio was estimated by image processing in 2016. Results showed that [NH4+-N] increased gradually after transplanting and then rapidly decreased from a certain day. This distinct drop in [NH4+-N] informed us the timing at which the rice root system reached the point of porous tubing and thus essentially covered the whole soil volume. The LAI at the dropping point was about 0.43 regardless of the cropping schedules in 2012 experiment. In 2016, the coverage ratio at the N dropping point was within the range of 0.12 to 0.19 for four genotypes having different growth durations. In addition, the coverage ratios at seven weeks after the transplanting showed a good correspondence to LAI across the four genotypes. We therefore conclude that both LAI and coverage ratio may serve as robust indicators for root development and might be useful to estimate the timing when the root system fully cover the soil volume. Results obtained here will also contribute to develop models that can predict not only above-ground canopy development but also associated below-ground processes.

• Journal of Korean Institute of Industrial Engineers
• /
• v.34 no.2
• /
• pp.223-234
• /
• 2008

Mobile multi-hop relaying (MMR) technology is being considered as a promising solution capable to enhance coverage, user throughput, and system capacity of the current wired backbone dependent wireless access networks. Since the relaying nodes do not need a wired backbone access, MMR technology offers easy and low-cost deployment, flexible cell planning, and adaptive traffic handling performance. In this paper, we investigate performance and cost effectiveness of the MMR technology deployment in the IEEE802.16j based WiBro/WiMAX systems. We first introduce standardization activities and research issues of MMR WiBro/ WiMAX systems. Since the coverage extension problem may occur in metropolitan areas as well as suburban or rural areas where user density is relatively low or moderate, we introduce several MMR topologies and analyze cost-effectiveness of MMR based coverage extension with respect to the user traffic density. Then, we argue cost effect on MMR technology deployment and throughput performance, Finally, we introduce further study issues including sectorized base station based MMR deployment approaches and the single and multi-frame structure MMR approaches.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.43 no.8 s.350
• /
• pp.27-34
• /
• 2006

During Built-In Self-Test(BIST), The set of patterns generated by a pseudo-random pattern generator may not provide sufficiently high fault coverage and many patterns were undetected fault. In order to reduce the test time, we can remove useless patterns or change from them to useful patterns. In this paper, we reseed modify the pseudo-random and use an additional bit flag to improve test length and achieve high fault coverage. the fat that a random tset set contains useless patterns, so we present a technique, including both reseeding and bit modifying to remove useless patterns or change from them to useful patterns, and when the patterns change, we choose number of different less bit, leading to very short test length. the technique we present is applicable for single-stuck-at faults. the seeds we use are deterministic so 100% faults coverage can be achieve.

• Journal of the Korean Magnetics Society
• /
• v.1 no.2
• /
• pp.1-8
• /
• 1991

The electronic and magnetic structure of Fe overlayers on W(110) is determined by means of the all-electron local spin density full potential linearized augmented plane wave (FLAPW) method with a single slab approach. Charge and spin densities, magnetic moments, contact hyperfine fields, and layer projected density of states (LDOS) are presented. For bilayer Fe coverage, we find magnetic moments to be 2.90 and 2.30 ${\mu}_B$ for the surface and subsurface Fe layers, respectively, corresponding to a 18% enhancement of the total magnetization compared with the calculated bulk value (2.22${\mu}_B$);For monolayer coverage the moment is 2.56 ${\mu}_B$ which is enhanced by 16% compared to bulk. Unusual changes in the magnetic hyperfine interaction are found in going from a monolayer to a bilayer coverage. Comparison of the results to the theoretical ones of the clean Fe(110) to discuss the hybridization and the negative pressure effects. We discuss our results by comparing them to experimental results.