• International Journal of Railway
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• v.1 no.2
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• pp.64-71
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• 2008

The quality of track-bed fills of railways has been controlled by field measurements of density $({\gamma}_d)$ and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The Key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of OMC${\pm}$2% as well as the p-wave velocity.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.553-558
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• 2013

Background Skin-sparing mastectomy with immediate breast reconstruction is increasingly becoming a proven surgical option for early-stage breast cancer patients. Areola-sparing mastectomy (ASM) has also recently become a popular procedure. The purpose of this article is to investigate the reconstructive and aesthetic issues experienced with one-stage nipple and breast reconstruction using ASM. Methods Among the patients who underwent mastectomy between March 2008 and March 2010, 5 women with a low probability of nipple-areolar complex malignant involvement underwent ASM and immediate breast reconstruction with simultaneous nipple reconstruction using the modified C-V flap. The cosmetic outcomes of this series were reviewed by plastic surgeons and patient self-assessment and satisfaction were assessed via telephone interview. Results During the average 11-month follow-up period, there were no cases of cancer recurrence, the aesthetic outcomes were graded as excellent to very good, and all of the patients were satisfied. Two patients developed a gutter-like depression around the reconstructed nipple, and one patient developed skin erosion in a small area of the areola, which healed with conservative dressing. The other complications, such as necrosis of the skin flap or areola, seroma, hematoma, or fat necrosis did not occur. Conclusions Since one-stage nipple and breast reconstruction following ASM is an oncologically safe, cost-effective, and aesthetically satisfactory procedure, it is a good surgical option for early breast cancer patients.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.281-286
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• 2005

The goal in facial paralysis treatment is to achieve the normal appearance of the face as well as to reconstruct the natural symmetrical smile. In cases of facial paralysis, a widely accepted procedure is the two stage method, which combines neurovascular free muscle transfer with cross face nerve grafting. Although the results are promising, the two operations of this method, which are about 1 year apart, impose an economic burden on the patients and require a lengthy period before results are obtained. In order to overcome these drawbacks, one stage method, using latissimus dorsi neurovascuular free muscle flap was introduced. Between January 2000 and January 2004, fifteen patients with long standing facial paralysis were treated in the Korea University Anam Hospital. The segmental latissimus dorsi with long nerve and pedicle was transferred to the paralyzed side of the face. The first postoperative movement of the transferred muscle was reported at 8.9 months, faster than that of the two stage method. During the next 24 months, a constant increase in the power of muscle contraction was observed. The fifteen cases were evaluated within an average of 31.7 months following the surgery and satisfactory results including muscle contraction were obtained in eleven of the cases but muscle contraction was not found in three cases.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.539-557
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• 1998

This article is concerned with the problem of estimating the mean of a one-parameter exponential family through sequential sampling in three stages under quadratic error loss. This more general framework differs from those considered by Hall (1981) and others. The differences are : (i) the estimator and the final stage sample size are dependent; and (ii) second order approximation of a continuously differentiable function of the final stage sample size permits evaluation of the asymptotic regret through higher order moments. In particular, the asymptotic regret can be expressed as a function of both the skewness $\rho$ and the kurtosis $\beta$ of the underlying distribution. The conditions on $\rho$ and $\beta$ for which negative regret is expected are discussed. Further results concerning the stopping variable N are also presented. We also supplement our theoretical findings wish simulation results to provide a feel for the triple sampling procedure presented in this study.

• Journal of Korean Institute of Industrial Engineers
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• v.12 no.1
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• pp.73-80
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• 1986

This paper deals with the problem of the optimal location of warehouses in the two stage distribution system, i.e., the distribution system where the product is transported from plants to customer areas via warehouses. The Problem is formulated with a zero-one mixed integer programming and an efficient branch and bound algorithm is then used to solve the problem. In order to obtain the solution of this problem, this paper shows the procedure of conversion of two stage distribution system into one stage distribution system. An improved method of solving the linear programming at the nodes and branching decision rule is also showed by this study.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.10
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• pp.1021-1027
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• 2009

Finite element models of dynamic systems can be updated in two stages. In the first stage, mass and stiffness matrices are updated neglecting damping. In the second stage, a damping matrix is estimated with the mass and stiffness matrices fixed. Methods to estimate a damping matrix for this purpose are proposed in this paper. For a system with proportional damping, a damping matrix is estimated using the modal parameters extracted from the measured responses and the modal matrix calculated from the mass and stiffness matrices from the first stage. For a system with non-proportional damping, a damping matrix is estimated from the impedance matrix which is the inverse of the FRF matrix. Only one low or one column of the FRF matrix is measured, and the remaining FRFs are synthesized to obtain a full FRF matrix. This procedure to obtain a full FRF matrix saves time and effort to measure FRFs.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.93-99
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• 2007

Purpose: To report the clinical results and efficacies of one stage reverse lateral supramalleolar adipofascial flap for soft tissue reconstruction of the foot and ankle joint. Material and Methods: We performed 5 cases of one stage reverse lateral supramalleolar adipofascial flap from Jan 2005 to Sept 2005. All patients were males and mean age was 50(36~59) years old. The causes of soft tissue defects were 1 diabetic foot, 2 crushing injuries of the foot, 1 open fracture of the calcaneus, and 1 chronic osteomyelitis of the medial cuneiform bone. Average size of the flap was 3.6(3~4)${\times}$4.6(4~6) cm. All flaps were harvested as adipofascial flap and were performed with the split-thickness skin grafts (STSG) above the flaps simultaneously. Results: All flap survived completely and good taking of STSG on the flap was achieved in all cases. There were no venous congestion and marginal necrosis of the flap. In diabetic foot case, wound was healed at 4 weeks after surgery due to wound infection. There was no contracture on the grafted sites. Ankle and toe motion were not restricted at last follow up. All patients did not have difficulty in wearing shoes. Conclusion: The reverse lateral supramalleolar adipofascial flap and STSG offers a valuable option for repair of exposure of the tendon and bone around the ankle and foot. Also one stage procedure with STSG can give more advantages than second stage with FTSG, such as good and fast take-up, early ambulation and physical therapy, and good functional result.

• Structural Engineering and Mechanics
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• v.27 no.5
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• pp.527-540
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• 2007

The modal controller of single-input system cannot stabilize the defective system with positive real part of repeated eigenvalues, because some of the generalized modes are uncontrollable. In order to stabilize the uncontrollable modes with positive real part of eigenvalues, the multi-input system should be introduced. This paper presents a recursive procedure for designing the feedback controller of the multi-input system with defective repeated eigenvalues. For a nearly defective system, we first transform it into a defective one, and apply the same method to manage. The proposed methods are based on the modal coordinate equations, to avoid the tedious mathematic manipulation. As an application of the presented procedure, two numerical examples are given at end of the paper.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1427-1439
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• 2008

The quality of track-bed fills of railways has been controlled by field measurements of density (${\gamma}_d$) and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures is that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of $OMC{\pm}2%$ as well as the p-wave velocity.

• Quantitative Bio-Science
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• v.37 no.2
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• pp.133-141
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• 2018

Graphical lasso is one of the most popular methods to estimate a sparse precision matrix, which is an inverse of a covariance matrix. The objective function of graphical lasso imposes an ${\ell}_1$-penalty on the (vectorized) precision matrix, where a tuning parameter controls the strength of the penalization. The selection of the tuning parameter is practically and theoretically important since the performance of the estimation depends on an appropriate choice of tuning parameter. While information criteria (e.g. AIC, BIC, or extended BIC) have been widely used, they require an asymptotically unbiased estimator to select optimal tuning parameter. Thus, the biasedness of the ${\ell}_1$-regularized estimate in the graphical lasso may lead to a suboptimal tuning. In this paper, we propose a two-staged bias-correction procedure for the graphical lasso, where the first stage runs the usual graphical lasso and the second stage reruns the procedure with an additional constraint that zero estimates at the first stage remain zero. Our simulation and real data example show that the proposed bias correction improved on both edge recovery and estimation error compared to the single-staged graphical lasso.