• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.73-82
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• 2014

The LM algorithm is used in solving the least square problem in a non linear system, and is used in various fields. However, in cases the applied field's target functionis complicated and high-dimensional, it takes a lot of time solving the inner matrix and vector operations. In such cases, the LM algorithm is unsuitable in embedded environment and requires a hardware accelerator. In this paper, we implemented the LM algorithm in hardware. In the implementation, we used pipeline stages to divide the target function operation, and reduced the period of data input of the matrix and vector operations in order to accelerate the speed. To measure the performance of the implemented hardware, we applied the refining fundamental matrix(RFM), which is a part of 3D reconstruction application. As a result, the implemented system showed similar performance compared to software, and the execution speed increased in a product of 74.3.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.3-7
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• 2000

The authors have realized reconstruction of 3D shape using contacting method with pins and TCP/IP communication. In this paper, the working principal of the mechanism is proposed and tested. A special sensor system is designed as 148 matrix form to measure 3D shape. When contact occurs between pin and the plate of the sensor matrix, the position information of pins is sent to computer and raised height data of the pin is obtained by counter which accumlates encoder signal. So, all datum which contain 3-dimensional coordinate, is transferred using TCP/IP communication. Finally, 3D shape is reconstructured by Web browser of remote computer. The measuring result shows that the proposed mechanism is reliable and promising as a remote measuring device through Internet.

• Archives of Plastic Surgery
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• v.48 no.2
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• pp.185-188
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• 2021

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome can be treated through numerous surgical and nonsurgical methods. We present a surgical technique in which a neovagina was reconstructed and shaped by a vaginal expander with acellular porcine dermal matrix (XCM Biologic Tissue Matrix) and mucosal interposition using microfragments harvested from the hymen. In our case, we found this procedure to be safe and effective, resulting in satisfactory sexual function and good cosmetic results, without donor site morbidity. To our best knowledge, this tissue-engineered biomaterial has never been used for vaginal reconstruction before.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.102-105
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• 1989

In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research.

• Smart Structures and Systems
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• v.28 no.6
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• pp.827-838
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• 2021

The dynamic displacement is considered to be an important indicator of structural safety, and becomes an indispensable part of Structural Health Monitoring (SHM) system for high-speed railway bridges. This paper proposes an indirect strain based dynamic displacement reconstruction methodology for high-speed railway box girders. For the typical box girders under eccentric train load, the plane section assumption and elementary beam theory is no longer applicable due to the bend-torsion coupling effects. The monitored strain was decoupled into bend and torsion induced strain, pre-trained multi-output support vector regression (M-SVR) model was employed for such decoupling process considering the sensor layout cost and reconstruction accuracy. The decoupled strained based displacement could be reconstructed respectively using box girder plate element analysis and mode superposition principle. For the transformation modal matrix has a significant impact on the reconstructed displacement accuracy, the modal order would be optimized using particle swarm algorithm (PSO), aiming to minimize the ill conditioned degree of transformation modal matrix and the displacement reconstruction error. Numerical simulation and dynamic load testing results show that the reconstructed displacement was in good agreement with the simulated or measured results, which verifies the validity and accuracy of the algorithm proposed in this paper.

• Archives of Plastic Surgery
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• v.46 no.5
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• pp.475-479
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• 2019

The Goldilocks technique for breast reconstruction utilizes redundant mastectomy flap tissue to construct a breast mound. This technique is suitable for women who decline, or are poor candidates for, traditional postmastectomy reconstruction. Moreover, this technique can be applied in secondary operations after the failure of initial reconstruction efforts. A 74-year-old patient underwent the Goldilocks procedure after reconstruction failure with an implant and acellular dermal matrix. At her 6-month follow-up, the cosmetic outcome of the procedure was satisfactory, and no complications were noted. Therefore, the Goldilocks procedure is a safe alternative to reconstruct breast mounds following reconstruction failure, especially in obese patients.

• Journal of Yeungnam Medical Science
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• v.36 no.3
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• pp.201-207
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• 2019

Implant-based breast reconstruction is the most commonly used reconstruction technique after mastectomy. This is because skin-sparing mastectomy has become possible with advancements in oncology. In addition, the development of breast implants and the advent of acellular dermal matrices have reduced postoperative complications and resulted in superior cosmetic results. The most frequently performed surgical breast reconstruction procedure for the past 20 years was the insertion of an implant under the pectoralis major muscle by means of the dual plane approach. However, some patients suffered from pain and animation deformity caused by muscle manipulation. Recently, a prepectoral approach has been used to solve the above problems in select patients, and the results are similar to subpectoral results. However, this technique is not always chosen due to the number of considerations for successful surgery. In this article, we will discuss the emergence of prepectoral breast reconstruction, indications and contraindications, surgical procedures, and outcomes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.5015-5038
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• 2018

In this paper, a novel spectral-spatial joint sparse representation algorithm for hyperspectral image classification is proposed based on multi-layer superpixels in various scales. Superpixels of various scales can provide complete yet redundant correlated information of the class attribute for test pixels. Therefore, we design a joint sparse model for a test pixel by sampling similar pixels from its corresponding superpixels combinations. Firstly, multi-layer superpixels are extracted on the false color image of the HSI data by principal components analysis model. Secondly, a group of discriminative sampling pixels are exploited as reconstruction matrix of test pixel which can be jointly represented by the structured dictionary and recovered sparse coefficients. Thirdly, the orthogonal matching pursuit strategy is employed for estimating sparse vector for the test pixel. In each iteration, the approximation can be computed from the dictionary and corresponding sparse vector. Finally, the class label of test pixel can be directly determined with minimum reconstruction error between the reconstruction matrix and its approximation. The advantages of this algorithm lie in the development of complete neighborhood and homogeneous pixels to share a common sparsity pattern, and it is able to achieve more flexible joint sparse coding of spectral-spatial information. Experimental results on three real hyperspectral datasets show that the proposed joint sparse model can achieve better performance than a series of excellent sparse classification methods and superpixels-based classification methods.

• Archives of Plastic Surgery
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• v.46 no.6
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• pp.544-549
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• 2019

Background As the indications for postmastectomy radiotherapy expand, innovative solutions are required to reduce operative complications and reconstructive failure after prosthetic breast reconstruction. In this study, we investigated the effectiveness of acellular dermal matrix (ADM) inlay grafts in preventing postoperative wound dehiscence of irradiated breasts in the context of prosthetic breast reconstruction. Methods A retrospective analysis was conducted of 45 patients who received two-stage prosthetic reconstruction and radiotherapy following mastectomy. An ADM graft was placed beneath the incisional site during the second-stage operation in 19 patients using marionette sutures, whereas the control group did not receive the ADM reinforcement. Patient demographics and complications such as wound dehiscence, capsular contracture, peri-prosthetic infection, cellulitis, and seroma were compared between the two groups. Results During an average follow-up period of 37.1 months, wound dehiscence occurred significantly less often in the ADM-reinforced closure group (0%) than in the non-ADM group (23.1%) (P=0.032). There was no significant difference between the two groups in relation to other complications, such as capsular contracture, postoperative infection, or seroma. Conclusions The ADM inlay graft is a simple and easily reproducible technique for preventing incisional dehiscence in the setting of radiotherapy after prosthetic breast reconstruction. The ADM graft serves as a buttress to offload tension during healing and provides a mechanical barrier against pathogens. Application of this technique may serve to reduce complications in prosthetic breast reconstruction after radiotherapy.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.158-165
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• 2022

Background Implant-based breast reconstruction has evolved tremendously in the last decades, mainly due to the development of new products and techniques that make the procedure safer and more reliable. The purpose of this study was to compare the outcomes in immediate one-stage breast reconstruction between acellular dermal matrix (ADM) and inferior dermal flap (IDF). Methods We conducted a retrospective comparative study of patients submitted to immediate breast reconstructions with an anatomical implant and ADM or IDF in a single center between 2016 and 2018. Outcomes evaluated included major complications, early complications, reinterventions, readmissions, and reconstruction failure. Simple descriptive statistics and univariate analysis were performed. Results A total of 118 breast reconstructions (85 patients) were included in the analysis. Patients in the IDF group had a higher body mass index (median = 27.0) than patients in the ADM group (median = 24). There were no statistically significant differences among both groups regarding immediate major complication, early complications, readmissions, and reinterventions. Conclusion There are no significant differences in complications between the ADM and IDF approach to immediate implant breast reconstruction. In patients with higher body mass index and large, ptotic breasts, we recommend an immediate implant reconstruction with IDF.