• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.1
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• pp.52-63
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• 2008

The side collision reconstruction algorithm is developed using three dimensional car crash analysis. Medium size passenger car is modeled for finite element analysis. Total 24 side collision configurations, four different speed and six different angle, are set up for making side collision database. Deformation index and degree index are built up for each collision case. Deformation index is a kind of deformation estimate averaging displacement of side door of crashed car from finite element analysis result. Angle index is constructed measuring deformed angle of crashing car. There are two kinds of angle index, one is measured at driver's side and the other is measured at passenger's side. Also a collision analysis information in side of cars is used for giving a basis for scientific and practical reason in a reconstruction of the car accident. The analysis program, LS-DYNA3D is utilized for finite element analysis program for a collision analysis. Those database are used for side collision reconstruction. Side collision reconstruction algorithm is developed, and applied to find the collision conditions before the accident occurs. Three example collision cases are tried to check the effectiveness of the algorithm. Deformation index and angle index is extracted for the case from the analysis result. Deformation index is compared to the established database, and estimated collision speed and angle are introduced by interpolation function. Angle index is used to select a specific collision condition from the several available conditions. The collision condition found by reconstruction algorithm shows good match with original condition within 10% error for speed and angle. As a result, the calculation from the reconstruction of the situation is reproducing the situation well. The performance in this study can be used in many ways for practical field using deformation index and degree index. Other different collision situations may be set up for extending the scope of this study in the future.

• Journal of Korea Spatial Information System Society
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• v.7 no.3 s.15
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• pp.119-130
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• 2005

A spatial data warehouse is a system that stores geographical information as a subject oriented, integrated, time-variant, non-volatile collection for efficiently supporting decision. This system consists of a builder and a spatial data warehouse server. A spatial data warehouse server suspends user services, stores transferred data in the data repository and constructs index using stored data for short response time. Existing methods that construct index are bulk-insertion and index transfer methods. The Bulk-insertion method has high clustering cost for constructing index and searching cost. The Index transfer method has improper for the index reconstruction method of a spatial data warehouse where periodic source data are inserted. In this paper, the efficient index reconstruction method using a partial index in a spatial data warehouse is proposed. This method is an efficient reconstruction method that transfers a partial index and stores a partial index with expecting physical location. This method clusters a spatial data making it suitable to construct index and change treated clusters to a partial index and transfers pages that store a partial index. A spatial data warehouse server reserves sequent physical space of a disk and stores a partial index in the reserved space. Through inserting a partial index into constructed index in a spatial data warehouse server, searching, splitting, remodifing costs are reduced to the minimum.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.732-735
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• 2010

Purpose: In performing breast reconstruction, making symmetrical breast is still a challenge. A precise estimate of the volume of the breast specimen is necessary to reconstruct a symmetrical and aesthetically pleasing breast. This study aims at finding out the relationship with breast tissue density and body mass index designed to apply for breast reconstruction. Methods: By using the Archimedes' principle, the authors calculated the volume of the breast specimen and drew a correlation between the density of breast specimen and BMI. From October 2002 to November 2004, this method was used on 197 patients to predict breast volume for TRAM flap reconstruction. Results: The mean density was 0.9954g/cc and had no correlation with BMI (p-value=0.069). There was no difference between denstiy of breast tissue after skin spared mastectomy and that of breast tissue after nipple spared mastectomy. Conclusion: These data will be helpful to predict the needed volume for breast reconstruction.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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• pp.49-56
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• 2009

In this study, a side collision accident reconstruction using database based on the deformed shape information from the collision test using model cars is suggested. A deformation index and angle index related to the deformed shape is developed to set the database for the collision accident reconstruction algorithm. Two small size RC cars are developed to carry out the side collision test. Several side collision tests according to the velocity and collision angles are performed for establishing the side collision database. A high speed camera with 1000fps is used to capture the motion of the car. A side collision accident reconstruction algorithm is developed and applied to find the collision conditions before the accident occurs. Two collision cases are tested to validate the database and the algorithm. The results obtained by the reconstruction algorithm show good match with original conditions with regard to the velocity and angle.

• International Journal of Air-Conditioning and Refrigeration
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• v.8 no.2
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• pp.11-22
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• 2000

Holographic interferometric tomography can provide reconstruction of instantaneous three-dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80$\circ$. The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.87-94
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• 2012

The apartment reconstruction projects have the proper functions such as residential environment improvement and the new housing allocation system; however, intention of the projects are distorted by the combination of factors, like failure of relocation of the original occupants and income redistribution, speculation in real estate, sharp rise in housing price, disputation between various interested parties, inadequate system and etc and it makes the projects unable to go well. Disputations and litigations are due to spread of the small conflict. As a result of the problems, it could not going smoothly and that lead to increase or stop the period and cost. This study is to estimate the period and cost using the conflict index so as to prevent and solve the problem which is among the conflict in the reverse functions. The conflict index has estimated focus on the conflict impact and the period and cost has been estimated using an variable independent including the conflict index. Also, estimated the conflict index and estimate of the period and cost are able to succeed with a minimum of disputation and money.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4591-4596
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• 2023

Single-photon emission computed tomography SPECT image reconstruction methods have a significant influence on image quality, with filtered back projection (FBP) and ordered subset expectation maximization (OSEM) being the most commonly used methods. In this study, we proposed newly-designed adaptive non-blind deconvolution with a structural similarity (SSIM) index that can take advantage of the FBP and OSEM image reconstruction methods. After acquiring brain SPECT images, the proposed image was obtained using an algorithm that applied the SSIM metric, defined by predicting the distribution and amount of blurring. As a result of the contrast to noise ratio (CNR) and coefficient of variation evaluation (COV), the resulting image of the proposed algorithm showed a similar trend in spatial resolution to that of FBP, while obtaining values similar to those of OSEM. In addition, we confirmed that the CNR and COV values of the proposed algorithm improved by approximately 1.69 and 1.59 times, respectively, compared with those of the algorithm involving an inappropriate deblurring process. To summarize, we proposed a new type of algorithm that combines the advantages of SPECT image reconstruction techniques and is expected to be applicable in various fields.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.1
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• pp.27-36
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• 2000

As a potential approach for non-destructive testing of concrete structures, we evaluate the time-of-flight (TOF) ultrasound tomography technique In conventional X ray tomography, the reconstructed Image corresponds to the internal attenuation coefficient However, in TOF ultrasound tomography, the reconstructed Image is proportional to the retractive index of the medium Because refractive effects are minimal for X-rays, conventional reconstruction techniques are applied to reconstruct the Image in X-ray tomography However, since ultrasound travels in curved path, due to the spatial variations in the refractive index of the medium, the path must be known to correctly reconstruct the Image. Algorithm for determining the ultrasound path is developed from a Geometrical Optics point view and the image reconstruction algorithm, since the paths are curved It requires the algebraic approach, namely the ART or the SIRT Here, the difference between the computed and the measured TOP data is used as a basis, for the iteration process First the initial image is reconstructed assuming straight paths. It then updates the path based on the recently reconstructed image This process of reconstruction and path determination repeats until convergence The proposed algorithm is evaluated by computer simulations, and in addition is applied to a real concrete structure.

• Archives of Plastic Surgery
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• v.39 no.1
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• pp.71-75
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• 2012

Recurrent laryngeal nerve paralysis is the most common and serious complication after thyroid cancer surgery. The objective of this study was to report the advantages of the vein wrapping technique for nerve reconstruction in patients with thyroid cancer invading the recurrent laryngeal nerve and its effects on postoperative phonatory function. The subjects were three patients who underwent resection of the recurrent laryngeal nerve during surgical extirpation of papillary thyroid cancer. Free ansa cervicalis nerve graft or direct neurorrhaphy with a vein wrapping technique was used to facilitate nerve regeneration, protect the anastomosed nerve site mechanically, and prevent neuroma formation. One-year postoperative laryngoscopic examination revealed good vocal cord mobility. Maximum phonation time ($19.5{\pm}0.3$ sec) was longer than a previously-reported value in conventional reconstruction patients ($18.8{\pm}6.6$ sec). The present phonation efficiency index ($7.88{\pm}0.78$) was higher than that previously calculated in conventional reconstruction ($7.59{\pm}2.82$). The mean value of the Voice Handicap Index-10 was 6, which was within the normal range. This study demonstrates improvement in phonation indices measured 1 year after recurrent laryngeal nerve reconstruction. Our results confirm that the vein wrapping technique has theoretical advantages and could be favored over conventional reconstruction techniques for invenerate nerve injuries.

• 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.