• Journal of the Korean Geotechnical Society
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• v.37 no.7
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• pp.13-23
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• 2021

If roads, bridges, buildings, etc. are built on the ground with soft clay or organic soil, there may be a lot of problems in geotechnical engineering such as settlement and stability due to the large settlement and lack of bearing capacity. In extreme cases, it may appear due to shear failure or collapse of the constructed structure, so a ground improvement method is indispensable to increase the strength of the ground and to suppress settlement. In this study, the settlement according to each groundwater level condition was analyzed using the measurement results for the groundwater level conditions, one of the important factors in predicting the settlement in dredged and reclaimed ground, and the groundwater level conditions applied to the settlement analysis were proposed by comparing it with settlement generated 5 years after construction. As a result of the analysis, it is judged that it is reasonable to apply the measured groundwater level during construction and the low water ordinary neap tide (L.W.O.N.T) during load application for the groundwater level in the settlement analysis. In addition, in the case of the dredged and reclaimed ground, it is estimated that the water pressure acting on the clay layer is nonlinear, as the result of the observations of the head of water at the observation points above and below the in-situ clay layer were different.

• (The) Research of the performance art and culture
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• no.37
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• pp.327-363
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• 2018

Bhutan's mask dance drama, Cham is performed in the festival of Tshechu. Originating from the 17th century, Tschechu is a religious ritual as well as a traditional festival held to commemorate the birth of Padmasambhava, who spread Buddhism in the kingdom of Bhutan. Bhutanese Cham and Tibetan Cham share similar traits in their content of , , and in their characters of Pawo and Pamo. Meanwhile, , , , , , , , are distinctive performances of Bhutanese cham. Moreover, the clown character Atsara in Bhutanese cham is a character that does not appear in the Tibetan Cham. Atsara, a humorous character, can be identified by its use of a long phallus ornament on the head or by a distorted face mask with a phallus in its hand. Bhutanese Cham, originally from Tibet, is a religious mask dance drama handed down in Lamaism temples. In later generations, new performances reflective of Bhutan's history, myth, legends, and religion were added in large amount. Thus, the Cham of Bhutan now has very independent and characteristic aspects.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.178-188
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• 2019

When using a distributed system, it is very important to know the intention of a target ship in order to prevent collisions. The action taken by a certain ship for collision avoidance and the action of the target ship it intends to avoid influence each other. However, it is difficult to establish a collision avoidance plan in consideration of multiple-ship situations for this reason. To solve this problem, a Distributed Stochastic Search Algorithm (DSSA) has been proposed. A DSSA searches for a course that can most reduce cost through repeated information exchange with target ships, and then indicates whether the current course should be maintained or a new course should be chosen according to probability and constraints. However, it has not been proven how the parameters used in DSSA affect collision avoidance actions. Therefore, in this paper, I have investigated the effect of the parameters and weight factors of DSSA. Experiments were conducted by combining parameters (time window, safe domain, detection range) and weight factors for encounters of two ships in head-on, crossing, and overtaking situations. A total of 24,000 experiments were conducted: 8,000 iterations for each situation. As a result, no collision occurred in any experiment conducted using DSSA. Costs have been shown to increase if a ship gives a large weight to its destination, i.e., takes selfish behavior. The more lasting the expected position of the target ship, the smaller the sailing distance and the number of message exchanges. The larger the detection range, the safer the interaction.

• Journal of the Korean Society of Radiology
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• v.14 no.7
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• pp.975-980
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• 2020

Cervical neural foraminal stenosis is a very common spinal disease that affects a relatively large number of people of all ages. However, since imaging methods that quantitatively provide neural foraminal stenosis are lacking, this study attempts to present quantitative measurement results by reconstructing 3D computed tomography images. Using a 3D reconstruction software, the surrounding bones were removed, including the spinous process, transverse process, and lamina of the cervical spine so that the neural foramen were well observed. Using Image J, a region of interest including the neural foramen area of the 3D image was set, and the number of pixels of the neural foramen area was measured. The neural foramen area was calculated by multiplying the number of measured pixels by the pixel size. In order to measure the widest area of the neural foramen, it was measured between 40-50 degrees in the opposite direction and 15-20 degrees toward the head. The measured cervical neural foramen area showed consistent measurement values. The largest measured area of the right neural foramen C5-6 was 12.21 ㎟, and after 2 years, the area was measured to be 9.95 ㎟, indicating that 18% stenosis had progressed. Since 3D reconstruction using axial CT scan images, no additional radiation exposure is required, and the area of stenosis can be objectively presented. In addition, it is good to explain to patients with neural stenosis while viewing 3D images, and it is considered a good method to be used in the evaluation of the progression of stenosis and post-operative evaluation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.1
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• pp.57-78
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• 2022

The disc cutter and cutterbit, which are the most important factors to increase the excavation efficiency of TBM, are key factors in the design and construction of the cutter head. The arrangement, spacing, number, size, and material of disc cutters suitable for the ground conditions determine the success or failure of TBM construction. The disc cutter, which is a representative consumable part in TBM construction, can cause enormous disruption to the construction cost as well as the construction cost unless accurate prediction of wear and replacement cycle is accompanied. Therefore, in this study, the method of calculating the replacement cycle of the disc cutter calculated at the time of design for the slurry shield TBM field, and the depth of wear and replacement location of the disc cutter that occurred during actual construction were compared by analyzing the field data. For a quantitative comparison, weathered soil/weathered rock, soft rock, and hard rock were classified according to the ground in the section showing constant excavation data, and the trajectory of circle was different depending on the location of the disc cutter, so it was compared and analyzed.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.1
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• pp.93-114
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• 2023

Information extraction can facilitate the intensive analysis of documents by providing semantic triples which consist of named entities and their relations recognized in the texts. However, most of the research so far has been carried out separately for named entity recognition and relation extraction as individual studies, and as a result, the effective performance evaluation of the entire information extraction systems was not performed properly. This paper introduces two models of end-to-end information extraction that can extract various entity names in clinical records and their relationships in the form of semantic triples, namely pipeline and joint models and compares their performances in depth. The pipeline model consists of an entity recognition sub-system based on bidirectional GRU-CRFs and a relation extraction module using multiple encoding scheme, whereas the joint model was implemented with a single bidirectional GRU-CRFs equipped with multi-head labeling method. In the experiments using i2b2/VA 2010, the performance of the pipeline model was 5.5% (F-measure) higher. In addition, through a comparative experiment with existing state-of-the-art systems using large-scale neural language models and manually constructed features, the objective performance level of the end-to-end models implemented in this paper could be identified properly.

• Journal of the Korean Geotechnical Society
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• v.26 no.10
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• pp.61-68
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• 2010

A pilot-scale model test was performed to estimate the availability of new material, Fe-loaded zeolite, as the filling material in permeable reactive barrier (PRB) against the contaminated groundwater with both Cd and Cr(VI). Aquifer was simulated by filling up a large scale soil tank with sands, and mobilizing the water flow by the head difference of water level in both ends of the tank. Then, the mixture of concentrated Cd and Cr(VI) solution was injected into the aquifer to form a contaminant plume, and its behavior through Fe-loaded zeolite barrier was monitored. The test results showed that Fe-loaded zeolite barrier successfully treated the contaminant plume containing both Cd and Cr(VI) and that the immobilized contaminants in the barrier were not desorbed or released. The results indicated that the Fe-loaded zeolite could be a promising material in PRBs against the multiple contaminants with different ionic forms like Cr(VI) and Cd.

• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.5-12
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• 2008

Biot proposed the frequency dependent formulation for the propagation of elastic waves in saturated media based on the coupled theory mixtures. Based on Biot theory, a special frequency called 'the characteristic frequency' contains unique information of the permeability of soils. The characteristic frequency is measured from I/Q (inverse quality factor) versus frequency curve by an acoustic sweep test, and the permeability of soils is computed from Biot equation. In this paper, laboratory tests are performed at The University of Mississippi using a large test box. The measured characteristic frequency is consistently obtained at 3500 Hz for mortar sands. The computed permeability of mortar sands based on Biot equation turned out 2.01 $10^{-4}m/sec$, while the permeability from the laboratory constant head test turned out 1.49 $10^{-4}m/sec$. This paper addresses the theoretical background and experimental procedure of this technique.

• Analytical Science and Technology
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• v.21 no.4
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• pp.259-271
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• 2008

The analytical method of extracting compounds from human blood to examine accumulated organochlorine pesticides (OCPs) has been widely used the traditional liquid-liquid extraction (LLE) method and solid-phase extraction (SPE) method, yet these methods have certain limitations in purification and usafe of a large amount of sample. In order to overcome the se problems reside in these, solid-phase microextraction (SPME), known as a highly efficient extration method with less samples and relatively simple, was employed to collect 18 different kinds of OCPs in blood as extraction method in this study. To optimize extraction method, we examine various experimental SPME-parameters such as adsorption (fiber type, adsorption time, adsorption temperature, salting out effect), and desorption (desorption time, desorption temperature etc.). From the experimental results, the optimal conditions are as follows: fiber was polyacrylate with $85{\mu}m$, adsorption time was for 5 min, adsorption optimum temperature was at $280^{\circ}C$, and salting out effect was NaCl with 0.1 g. MDL, precision and accuracy was in the ranges of 0.05~0.20 ng/mL, 5.59~13.39%, respedively, and accuracy was -0.5% ~24.5% for all OCPs.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.121-128
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• 2023

Two specimens of Polymetme elongata (Phosichthyidae; Polymetme) were collected by a bottom trawl from both the southern coastal waters of Jejudo Island in October 2016 (70.65 mm SL) and Yellow Sea, Korea in August 2022 (54.04 mm SL). They are an elongated body with large mouth, 11 dorsal fin rays, 10 pectoral fin rays, 7 pelvic fin rays, 30~32 anal fin rays, 1 adipose fin, 18 gill rakers, 44 vertebrae, 1 preorbital photophore, 1~2 ventrolateral rows of photophores on body, 1 paired photophores in symphysis of lower jaw, 9 branchiostegal rays, 2 rows of 8 phorophores between pelvic fin origin and anal fin origin, and 1 row of 23 photophores thereafter. At the origin of anal fin, the second photophore is more higher than third photophore and the first photophore is most lowest. Our specimens differ from the other species of the same genus by the ratio of the head length to the standard length (1/5) and the gill rakers (18), absolutely. As this species is the first record of the family Phosichthyidae, genus Polymetme, and P. elongata in Korean waters, we suggest their new Korean names, "Gin-ael-tung-i-gwa", "Gin-ael-tung-i-sog", and "Gin-ael-tung-i", respectively.