• Journal of the Korean Geotechnical Society
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• v.38 no.12
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• pp.29-43
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• 2022

Various underground facilities are being constructed to improve the urban environment. Therefore, it is more necessary than ever to reasonably evaluate the seismic response of underground utility tunnels, playing a significant part in urban infrastructure. In this study, the major features and differences of two types of existing pseudo-static analysis methods are reviewed. Each method uses a simplified 2D frame model to represent the seismic behavior of underground structures. Applying each method to a one-barrel rectangular utility tunnel in Korea, the suitability in predicting seismic responses, especially the racking deformation of the tunnel, is examined. In addition, several precautions and suggestions are provided in this study against the inattentive application of the methods to seismic evaluation of underground structures.

• Journal of KIBIM
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• v.12 no.4
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• pp.19-31
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• 2022

With the development of 3D-based CAD (Computer Aided Design), attempts at freeform building design have expanded to small and medium-sized buildings in Korea. However, a standardized system for continuous utilization of shape data and BIM conversion process implemented with 3D-based NURBS is still immature. Without accurate review and management throughout the Freeform building project, interference between members occurs and the cost of the project increases. This is very detrimental to the project. To solve this problem, we proposed a continuous utilization process of 3D shape information based on BIM parameters. Our process includes algorithms such as Auto Split, Panel Optimization, Excel extraction based on shape information, BIM modeling through Adaptive Component, and BIM model utilization method using ID Code. The optimal cutting reference point was calculated and the optimal material specification was derived using the Panel Optimization algorithm. With the Adaptive Component design methodology, a BIM model conforming to the standard cross-section details and specifications was uniformly established. The automatic BIM conversion algorithm of shape data through Excel extraction created a BIM model without omission of data based on the optimized panel cutting reference point and cutting line. Finally, we analyzed how to use the BIM model built for automatic conversion. As a result of the analysis, in addition to the BIM utilization plan in the general construction stage such as visualization, interference review, quantity calculation, and construction simulation, an individual management plan for the unit panel was derived through ID data input. This study suggested an improvement process by linking the existing research on atypical panel optimization and the study of parameter-based BIM information management method. And it showed that it can solve the problems of existing Freeform building project.

• The Korea Journal of Herbology
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• v.32 no.2
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• pp.33-40
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• 2017

Objectives : This study is aimed at establishing the discriminative criteria for Adenophorae Radix (AT; Sasam), Codonopsis Lanceolatae Radix (CL; Yangyu) and Adenophorae Remotiflori Radix (AR; Jeni). Because of confusable publications and the similitude of herb shape, CL and AR have been used as AT in the markets. Methods : We firstly discriminated and confirmed AT, CL and AR through observing the external morphology of original plants. Then, external-internal morphological features of the medicinal herbs were studied. A stereoscope was used to determine macroscopic features of dried herbal medicines and a microscope was conducted to examine internal features with the samples, which were embedded in paraffin and stained. Results : 1. The original plant of CL was discriminated with the stem shape in comparison with others. AT and AR were classified by the leaf position of original plant. 2. In the macroscopic morphological study of medicinal herbs, CL had lumps, which seem like a wart. Also, AT and AR were different in the density of cross section. 3. In the microscopic morphological study of the medicinal herbs, the phloem, fissures and the arrangement of xylem were selected as discriminative criteria for 3 kinds of herbs. With these contents, we suggested the identification keys, including further details. Conclusions : These results, especially identification keys, will be helpful to distinguish 3 kinds of herbs, referred to as a 'Sasam'. Moreover, macroscopic and microscopic methods used in this article would be applicable tools for the discrimination of other herbs.

• The Korea Journal of Herbology
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• v.32 no.6
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• pp.49-54
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• 2017

Objectives : Bangki is commonly Sinomeni Caulis et Rhizoma (SC) in Korea. But it often confused with others such as Cocculi Radix (CR), Stephaniae Tetrandrae Radix (SR) and Aristolochiae Fangchi (AR) due to the similarity in herbal names and morphological characteristics. However, because all of these types of Bangi have different healing properties, they need to be differentiated. Methods : A discrimination on external features of original plants and external characteristics of herbal medicines was carried out using visual examination, stereoscope. For the examination of Internal characteristics of herbal medicines, tissues were dyed using fast green FCF, hematoxylin and safranin O, and the features were observed by the microscope. Results : In external morphology of original plants, the original plants of SC and AR were lignum plants and others were herbaceous plants. The leaf blade and the petiole were another discriminative criteria. In external morphology of herbal medicines, SR and AR have powders and others didn't. Also, SC and CR were determined by the dense of the radiation pattern in the cross section. In internal morphology of herbal medicines, SR and AR were distinguished by the dense of Stone cells. Moreover, SC and CR were different in the pattern of medullary ray and vascular bundle. Conclusions : The results above could be used as identification keys of Bangki. Moreover, these identifications might attribute as a fundamental material to further studies like physicochemical pattern analysis and biological reaction.

• The Korea Journal of Herbology
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• v.34 no.5
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• pp.1-12
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• 2019

Objectives : The consumption of licorice is large in Korea, but domestic production is insufficient due to the lack of adaptability. This study aimed to provide a morphological basis for adding interspecific hybrid licorice with improved adaptability to pharmacopoeia. Methods : This study was to establish identification criteria for the original plants, external and internal morphology of the authentic herbal medicines (Glycyrrhiza uralensis, G. glabra and G. inflata), market products and artificially interspecific hybrid forms of licorice. For this purpose, previous studies were investigated and visual and histological observations were carried out. We focused on the internal morphology by microscopic observation for securing objectivity. Finally, we proposed the identification keys for precise classification of each part. Results : 1) Original plant : Licorice species in the compendium were distinguished by the number of leaflets, presence of hair on the fruit, curvature and swelling of the fruit. 2) External morphology : Licorice species were distinguished by degree of powderiness, tearing gap, radial structure in the cross section and existence of protrusion of outer epidermis. 3) Internal morphology : Licorice species were distinguished by the degree of development of phloem fiber bundle, development of obliterated sieve, whether the secondary medullary ray are branched. In the case of interspecific hybrids, the characteristics of both species used for hybridization were mixed in all observation methods. Conclusions : These results suggest that the interspecific crossbred licorice is suitable for the pharmacopoeial standard. Therefore, it can be applied as a herbal medicine through additional supplementary study.

• The Korea Journal of Herbology
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• v.34 no.1
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• pp.33-42
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• 2019

Objectives : This study aimed to be used as basic data for obtaining excellent quality of Salvia miltiorrhiza (SM) root. Methods : SM cultivated in Anhui Bozou, Henan, Shandong, Henan Wenxian, Zhejiang, Hebei, Liaoning, Shanxi, Shaanxi Shangluo, Sichuan Zhongjiang, Sichuan Minyang and Jiangsu in China were gathered and its internal morphology and physicochemical patterns were analyzed. Results : Cross-section of sang plants according to cultivated regions in China showed that cork layers consisted of cells with four to six layers, cortex width was wide, and phloem was semilunar-shaped. Although there are forms layers, yet boundary was vague. It was observed that eight to ten vascular bundles were arranged in wooden parts in all directions and as a single line of vascular was distributed nearby form layers as it nears to the center. Tanshinon IIA identified a spot in the same location with standard product near by Rf 0.9 in the test identifying TLC of SM according to cultivated areas in China. The largest amount was 0.535% identified in Shandong and the lowest amount of 0.05% in Hebei. Salvianolic acid B identified a spot in the same location with standard product near by Rf 0.7 in the test identifying TLC of SM according to cultivated areas in China. The largest amount was 2.72% identified in Liaoning and the lowest amount of 0.825% in Jiangsu. Conclusions : The results are assumed to be used as basic data for obtaining excellent quality of SM oriental medical hers and distinguishing authentic or fake herbs.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.27 no.1
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• pp.15-26
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• 2023

The purpose of this study is to determine the artificial intelligence-based degradation index from the image of the cross-section of the microstructure taken with a scanning electron microscope of the specimen obtained by the creep test of DA-5161 SX, a nickel-based superalloy used as a material for high-temperature parts. It proposes a new method of quantification and proposes a model that predicts degradation based on Bayesian inference without destroying components of high-temperature parts of operating equipment and a creep life prediction model that predicts Larson-Miller Parameter (LMP). It is proposed that the new degradation indexing method that infers a consistent representative value from a small amount of images based on the geometrical characteristics of the gamma prime phase, a nickel-base superalloy microstructure, and the prediction method of degradation index and LMP with information on the environmental conditions of the material without destroying high-temperature parts.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.108-114
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• 2002

Red pine(Pinus densiflora) square timbers with 14.0 cm and 16.5 cm of face size and 24 m long were dried in a vacuum-press kiln and in a radio-frequency/vacuum(RF/V) kiln to compare drying rate, moisture content(MC) distribution and specific energy. RF/V drying rate was higher than vacuum-press drying rate. The effect of size of cross section on the RF/V drying rates were more pronounced than those of vacuum-press drying. The longitudinal- and the transverse MC distribution of dried square timber showed convex profile for the vacuum-press drying and concave profile for the RF/V drying. Moisture gradient of width direction was similar to the thickness direction in vacuum-press dried square timber and was more slight than that of the thickness direction in the RF/V dried large square timber. The specific energy consumption curve increased as MC decreased. Specific energy(kWh/kg of water evaporated) of the vacuum-press process required more than that of the RF/V process.

• Steel and Composite Structures
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• v.44 no.2
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• pp.199-210
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• 2022

This study build finite element analysis (FEA) models describing the bending events of coiled tubing (CT) at the wellhead and trips into the hole, accurately provide the state of stress and strain while the CT is in service. The bending moment and axial force history curves are used as loads and boundary conditions in the diametrical growth models to ensure consistency with the actual working conditions in field operations. The simulation diametrical growth results in this study are more accurate and reasonable. Analysis the factors influencing fatigue and diametrical growth shows that the internal pressure has a first-order influence on fatigue, followed by the radius of the guide arch, reel and the CT diameter. As the number of trip cycles increase, fatigue damage, residual stress and strain cumulatively increase, until CT failure occurs. Significant residual stresses remain in the CT cross-section, and the CT exhibits a residual curvature, the initial residual bending configuration of CT under wellbore constraints, after running into the hole, is sinusoidal. The residual stresses and residual bending configuration significantly decrease the buckling load, making the buckling and buckling release of CT in the downhole an elastic-plastic process, exacerbating the helical lockup. The conclusions drawn in this study will improve CT models and contribute to the operational and economic success of CT services.

• Structural Engineering and Mechanics
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• v.82 no.1
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• pp.1-16
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• 2022

This work elaborately investigates the influences of the guideway geometry parameters and track irregularity on the dynamic performances of the suspended monorail vehicle-guideway system (SMVGS). Firstly, a spatial dynamic analysis model of the SMVGS is established by adopting ANSYS parameter design language. Then, the dynamic interaction between a vehicle with maximum design load and guideway is investigated by numerical simulation and field tests, revealing the vehicle-guideway dynamic features. Subsequently, the influences of the guideway geometry parameters and track irregularity on the dynamic performances of the SMVGS are analyzed and discussed in detail, and the reasonable ranges of several key geometry parameters of the guideway are also obtained. Results show that the vehicle-guideway dynamic responses change nonlinearly with an increase of the guideway span, and especially the guideway dynamic performances can be effectively improved by reducing the guideway span; based on a comprehensive consideration of all performance indices of the SMVGS, the deflection-span ratio of the suspended monorail guideway is finally recommended to be 1/1054~1/868. The train load could cause a large bending deformation of the pier, which would intensify the car-body lateral displacement and decrease the vehicle riding comfort; to well limit the bending deformation of the pier, its cross-section dimension is suggested to be more than 0.8 m×0.8 m. The addition of the track irregularity amplitude has small influences on the displacements and stress of the guideway; however, it would significantly increase the vehicle-guideway vibrations and rate of load reduction of the driving tyre.