• Journal of the Korean Geotechnical Society
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• v.34 no.10
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• pp.29-38
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• 2018

The slime formed at the bottom of the borehole causes the excessive displacement and loss of the bearing capacity of the drilled shaft. In this study, the slime meter is developed for the evaluation of the slime based on the electrical properties of the fluid and the slime in the borehole. The slime meter is composed of a probe instrumented with electrodes and temperature sensor and a frame with rotary encoder, so that the slime meter profiles the electrical resistivity compensated with temperature effect along the depth. For the application of the slime meter, three field tests are conducted at a borehole with a diameter of 3 m and a depth of 46.9 m with different testing time and locations. For all the tests, the experimental results show that while electrical resistivities are constantly measured in the fluid, the electrical resistivities sharply increase at the surface of the slime. Therefore, the slime thicknesses are estimated by the differences in the depths of the slime surface and the ground excavation. The experimental results obtained at the same testing point with different testing time show that the estimated thickness of the slime increases by the elapsed time. Also, the estimated slime at the side of the borehole is thicker than that at the center of the borehole. As the slime meter estimates the slime in the borehole by measuring the electrical resistivity with simple equipment, the slime meter may be effectively used for the evaluation of the slime formed at the bottom of the borehole.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.3
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• pp.139-148
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• 2000

In this paper, the interaction of oblique incident waves with a bottom-mounted and fluid-filled flexible membrane structure is investigated in the frame of linear hydro-elastic theory. The static shape of a membrane structure containing the fluid of a specific density is initially unknown and must be calculated before the hydrodynamic analysis. To solve hydrodynamic problem, the fluid domain is divided into the inner and outer region. The inner solution based on discrete membrane dynamic model and simple-source distribution over the entire fluid boundaries is matched to the outer solution ba~ed on an eigenfunction expansion method. The numerical results were compared to a series of Ohyama's experimental results. The measured reflection and tran¬smission coefficients reasonably follow the trend of predicted values. Using the computer program developed, the performance of a bottom-mounted and fluid-filled flexible membrane strocture is tested with various system parameters (membrane shape, internal pressure, density ratio) and wave characteristics (wave frequencies, incident wave angle). It is found that a bottom-mounted and fluid-filled flexible membrane structure can be an effel;tive wave barrier if properly designed.

• Journal of the Korean Society of School Health
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• v.17 no.1
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• pp.85-95
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• 2004

Objectives : The aim of this study was to identify the trend of school health research by analyzing articles related to school health for the last 10 years. this information can be used to guide research direction for the future. Methods : This study is a descriptive study that analyzed annual data. using an objective frame of evaluation about the methodology and research domain in each paper, all the papers included in the journals concerning school health from January 1993 to December 2000 were analyzed. The data was processed statistically by frequency and percentage. Results : 455 papers in 9 journals related to school health were published. The Journal of the Korean Society of School Health had 204 articles, the highest number of any journal. most of the articles were descriptive, but the number of experimental studies increased over time. the most common research subjects were students were the greatest ones, but the trend to study both parents and teachers increased near the end of the sampling period. the most common selection of subjects appeared to be based on convenience, but probability sampling gradually increasing annually. the most common research instrument was the questionnaire and the reliability and the validity of instruments were described in approximately half of the studies. The survey was the most commonly used method of data collection. The papers that met ethical issue in data collection were less than those that did not. In addition, the papers that provided the rationale for the calculation of sample size were less than those that did not. parametric statistics were the main methods of data analysis, but some advanced statistics were used more often than simple descriptive statistics in the latter part of the sampling period. In general, limit of the studies were not frequently mentioned but more recommendations were made. regarding the characteristics of the research area, the assesment domain was remarkable. The rate of school health problem assesment was the highest among research subjects. Sex- related subjects were the highest in detail research subjects. Conclusions : The research of school health has increased quantitatively, but it is difficult to ascertain its qualitative development. Therefore, on the basis of the research completed up until now, more school-based intervention studies and longitudinal studies need to be another target for the evaluation of the effects of the school health service. as well, policy suggestion through international and cross-sectional comparison studies are needed to assist in the establishment of the long term direction of school health.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.884-891
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• 2020

The collapse of bridges can cause massive casualties and economic losses. Therefore, it is thus essential to evaluate the structural safety of bridges. For this task, structural reliability analysis, considering various bridge-related uncertainty factors, is often used. This paper proposes a new computational platform to perform structural reliability analysis for bridges and evaluate their structural safety under various loading conditions. For this purpose, a software package of reliability analysis, Finite Element Reliability Using MATLAB (FERUM), was integrated with MIDAS/CIVIL, which is a widely-used commercial software package specialized for bridges. Furthermore, a graphical user interface (GUI) control module has been added to FERUM to overcome the limitations of software operation. In this study, the proposed platform was applied to a simple frame structure, and the analysis results of the FORM (First-Order Reliability Method) and MCS (Monte Carlo simulation), which are representative reliability analysis methods, were compared. The proposed platform was verified by confirming that the calculated failure probability difference was less than 5%. In addition, the structural safety of a pre-stressed concrete (PSC) bridge was evaluated considering the KL-510 vehicle model. The proposed new structural reliability analysis platform is expected to enable an effective reliability-based safety evaluation of bridges.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.901-907
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• 2019

The aim of this study is to evaluate the ability of target localizations of Leksell GammaPlan(LGP) in Gamma Knife Subthalamotomy(or Pallidotomy, Thalamotomy) of functional diseases. To evaluate the accuracy of LGP's location settings, the difference Δr of the target coordinates calculated by LGP (or LSP) and author's algorithm was reviewed for 10 patients who underwent Deep Brain Stimulation(DBS) surgery. Δr ranged from 0.0244663 mm to 0.107961 mm. The average of Δr was 0.054398 mm. Transformation matrix between stereotactic space and brain atlas space was calculated using PseudoInverse or Singular Value Decomposition of Mathematica to determine the positional relationship between two coordinate systems. Despite the precise frame positioning, the misalignment of yaw from -3.44739 degree to 1.82243 degree, pitch from -4.57212 degree to 0.692063 degree, and rolls from -6.38239 degree to 7.21426 degree appeared. In conclusion, a simple in-house algorithm was used to test the accuracy for location settings of LGP(or LSP) in Gamma Knife platform and the possibility for Gamma Knife Subthalamotomy. The functional diseases can be treated with Gamma Knife Radiosurgery with safety and efficacy. In the future, the proposed algorithm for target localizations' QA will be a great contributor to movement disorders' treatment of several Gamma Knife Centers.

• Journal of KIISE:Software and Applications
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• v.35 no.9
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• pp.554-561
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• 2008

Prediction technique of user's intention can be used as a post-processing method for reducing the search space of an automatic speech recognizer. Prediction technique of system's intention can be used as a pre-processing method for generating a flexible sentence. To satisfy these practical needs, we propose a statistical model to predict speakers' intentions that are generalized into pairs of a speech act and a concept sequence. Contrary to the previous model using simple n-gram statistic of speech acts, the proposed model represents a dialogue history of a current utterance to a feature set with various linguistic levels (i.e. n-grams of speech act and a concept sequence pairs, clue words, and state information of a domain frame). Then, the proposed model predicts the intention of the next utterance by using the feature set as inputs of CRFs (Conditional Random Fields). In the experiment in a schedule management domain, The proposed model showed the precision of 76.25% on prediction of user's speech act and the precision of 64.21% on prediction of user's concept sequence. The proposed model also showed the precision of 88.11% on prediction of system's speech act and the Precision of 87.19% on prediction of system's concept sequence. In addition, the proposed model showed 29.32% higher average precision than the previous model.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.3
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• pp.160-163
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• 2008

$CO_2$ ocean sequestration is being considered as a way to earn a frame of time to change other industrial life pattern to overcome the global warming crisis. The method is to dilute the captured $CO_2$ into ocean by ejecting the liquefied $CO_2$ through nozzles. The main issue of such method is the effectiveness and safety, and in both problems the rising speed of those LCO2 droplet is the key parameter. In this paper, the rising speed of LCO2 droplets is numerically studied including the effect of the surfactant which can be residing along the density interface of the droplets. A front tracking method with a simple surface tension model is developed and the rising speed of the droplets is carefully investigated with varying the various parameters. It is demonstrated that the variable surface tension can change the deformation of the droplet, the flow near the interface, and the rising speed.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.204-210
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• 2006

Mobile phone has become one of the most essential thing in modern life. In the past, it was only means of cummunication among people. But now, the function of mobile phone is getting diversified. People listen to music, take pictures and play games with their mobile phone. According to the Research in Jan. 2005, members of Korean 3 mobile cummunication companies were 36 million. And the Research in Jan. 2006 shows that number of 2 million and 16 thousand of members are incresed in a year. (36million to 38million 16 thousands) Mobile game is the most popular fuction among teenagers. People like mobile game becase they can enjoy the mobile game anywhere with easy and simple way. So some companies are even launching dedicated phone for mobile game. And with the unification of platform, people can enjoy various kinds of mobile game now. Most of the mobile character bobies are divided into 2 parts such as 'Head parts' and 'Body parts'. If the body is divided into more than 4 parts, it is difficult to express emotions and actions of the character becase of the small screen of mobile phone. That is why most of the characters have 2 parts - divided body. I stadied how the Design Factor of Mobile Characters such as materials of characters, shape of characters and Frame of accessory's movement are used in the mobile game.

• Korea journal of population studies
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• v.18 no.2
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• pp.1-22
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• 1995

In this paper, the methods to measure the mean age at first marriage is examined, and by analysing data of Korean women for the period 1970-1990, the differences that each methods make on measurements of the mean age at first marriage are presented. The main findings were : The Hajnal's SMAM, the most used index in studies of the pattern of marriage in Korea, was not a measure based on the marriages for a specific period. The resulting biases, in cases of 1970-1990 Korean women, were below 0.3 year in age, which can be considered small, if the changes in the pattern of marriage in these periods took into account. But the possibility of bringing larger bias cannot be excluded. Also the direction of biases was toward raising the mean age when marriage was in upward tendency. Considering the availability of data in Korea, the utilization of the simple mean or the measure from Agarwala method according to the purpose is recommendable. The mean age at first marriage by Agarwala(ASMAM) meets with the one computed from a gross nuptiality table based on the cohort's marriage rates for a specific period. The time series of the proportion single by age groups obtained from the population censuses showed high consistency. However when they were compaired with those computed from sample surveys at a same point of time, significant differences(at $\alpha$=0.05) were found in some major age groups. It was also pointed out that these differences were not caused by the problems related with the sampling frame for surveys or the survey questions.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.103-112
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• 2014

Oh, hein-kuhn is a representative portrait photographer in Korea. His works, , , , which treated portraits of women are a bit different from those of the past that described the appearance of characters. The artist expressed the figure of inner side that conflicts and feels uneasy between 'family and society' and 'child and woman' along with the look of character. That is, he included specific aura which the whole of aunts and girls' group radiates by showing similar photos repeatedly, that we can be aware of 'aunt' and 'girl' by seeing them. The important technique of Oh, hein-kuhn's Portrait Photograph is 'repetition' of image. The artist delivers the meaning of the photo by looking at the character upright in the front and showing photos with similar frame repeatedly. Such form and content of the work as this might feel a bit boring, since it's very simple just like identification picture. However, the photos in the frames which do not move in the fixed position can deliver the meaning of work more clearly rather than the image which expresses flowing time and moving space, we can grasp the message that the artist intends to deliver rather quickly. In the environment of photograph production mainly with image transformation, Oh, hein-kuhn's works of authentic original work method definitely stand forth. Through the portraits of aunts and girls, the artist tells an aspect of our society and we reconfirm the reality through the portraits made by him.