• Journal of Distribution Science
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• v.14 no.9
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• pp.85-94
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• 2016

Purpose - Recently, Mobile technologies and devices including smart phones and tablets have increased the possibility of communicating with other people and sharing personal information without time and space restriction. In order to realize the market potential related to mobile technologies, a large number of internet services have been incorporated into mobile platforms. Especially, The number of MIM(Mobile Instant Messenger) users has been increasing dramatically and services using MIM platform also have diversified. In spite of drastic growth in markets related to MIM, there is little empirical research on MIM and users' behaviors. This study designed to examine the structural relationships among belongingness, loneliness, self-disclosure intention, system quality, and self-disclosure behavior in context of MIM. Research design, data, and methodology - Three hypotheses were about the relationship among belongingness, loneliness and self-disclosure intention. The other two hypotheses were about the moderating effect of system quality in the causal relationship between self-disclosure intention and self-disclosure behavior. The data was analyzed by structural equation modeling. Research data were obtained from 330 undergraduate students who were KakaoTalk users and total 314 valid questionnaires were used in the final analysis. Results - The results from this study are as follow. First, the belongingness and the loneliness had a significant impact on self-disclosure intention in MIM. Second, the self-disclosure intention in MIM also had a positive impact on the self-disclosure behavior. Lastly, there is a moderating effect of the system quality in the relationship between the self-disclosure intention and self-disclosure behavior in MIM. Specifically, the higher system quality level was perceived, the positive effect of the self-disclosure intention in MIM on the self-disclosure behavior was greater. Conclusions - Based on the results from this study, academic and practical implications can be drawn. First, the study extends the scope of research about SNS through focusing on MIM to be classified by closed type SNS and identifies the relationship between emotion, behavioral intention and behaviors in MIM. Second, this study provides strategic guidelines to increase the efficiency for promotion activity. Limitations for the study also should be discussed.

• Korean Journal of Plant Taxonomy
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• v.47 no.1
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• pp.27-45
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• 2017

A taxonomic study of the genus Hosta (Lilliaceae) in Korea was conducted based on morphological characteristics. Hosta clausa varieties share several characteristics (rhizomes with underground stolons, smooth scapes, and purple anthers). Hosta clausa var. normalis has an open perianth, long pistils, and fertile fruit. H. clausa var. clausa can be distinguished from H. clausa var. normalis by its closed perianth and sterile fruit. H. clausa var. geumgangensis has sterile fruit, green petioles, short pistils, and short narrow perianth tubes. H. clausa var. ensata has very narrow, sword-shaped leaves. It can be included in H. clausa var. normalis, which has a large degree of variation in leaf and petiole shape. H. jonesii has smooth scapes, yellow anthers, and bell-shaped flowers. It can be distinguished from the related species H. tsushimensis found on the Tushima islands in Japan by its wide perianth tube. H. yingeri is distinguished by its funnel-shaped flowers, 3 long and 3 short stamens, and smooth scape; the related species H. laevigata has 6 equally-sized stamens, narrowly lanceolate leaves, and wavy leaf margins. Because H. laevigata is not found in its type locality Isl. Heugsando, its taxonomic position must be determined at a later time. H. minor shares several characteristics (scapes with ridges and yellow-colored anthers) with the related taxa H. venusta. However, H. venusta is changed to H. minor var. venusta because it has overlapping characteristics in plant size, number of flowers, leaf size, and leaf shape. Consequently, the genus Hosta in Korea is classified into 5 species, 3 varieties, and 6 forms.

• Journal of Gastric Cancer
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• v.4 no.2
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• pp.126-130
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• 2004

Purpose: A Krukenberg tumor is an ovarian tumor of a signet-ring cell type. This tumor arises more commonly in young women, and the prognosis is poor. The primary focus of this tumor is often found at gastrointestinal malignancy, especially gastric cancer. We tried to identify the clinical characteristics of this tumor, and in that regard, this report might be helpful. Materials and Methods: We reviewed the 61 patients with Krukenberg tumors, who had been diagnosed at our hospital from 1994 to 2002, and retrospectively analyzed the clinical features. Results: The age distribution ranged from 15 to 59 years, and the mean age was 41 years. The most common symptom was a lower abdominal mass ($46\%$). Fourty-two cases ($77\%$) showed bilateral ovarian involvement, and the size of this tumor was variable, but in 24 cases ($4\%$) the size was $5\∼10$ cm for the largest diameter. Among 54 cases, 40 cases had ascites, and the volume of ascites was variable. The median survival of the 61 patients was 10 months, and Krukenberg tumor developed 19.7 months after the primary operation. The median survival durations of recurrence patterns were 20 months for the Krukenberg tumor alone, and 7 months for the Krukenberg tumor with peritoneal seeding. Conclusion: In young women treated with a gastrectomy, especially one for an advanced tumor, closed observation with abdominal ultrasonography or computed tomography to detect a Krukenberg tumor is recommended. The patient with a Krukenberg tumor alone has a better prognosis than one with a Krukenberg tumor combined peritoneal seeding. We will have to consider more progressive treatment for the patient with a Krukenberg tumor alone.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.237-245
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• 2011

Asphalt Plug Joint(APJ) is a new type of expansion joint that it's application are increased in USA as well as several European countries. APJ's' advantages are cheap construction and maintenance costs, and simple construction and securing of excellent flatness. However, APJ's usability is hindered because it showed a problem of premature failure. Research for solving this problem has been progressed, and FEM analysis among existing researches was peformed. However, the behavior of APJ was insufficiently analyzed and the reliability of the analysis was much low, since the material showing complicated behavior was oversimplified, Therefore, a material model was proposed and its effectiveness was confirmed by comparing it with actual behavior in order to improve the reliability of FEM analysis in this paper. ABAQUS program was used for FEM analysis, and an elasto-plastic model and a viscous-plastic model as the material model of APJ were suggested on the base of experiment results of APJ material performed by Bramel et al. The elasto-plastic model was defined by time-independent analysis since it didn't consider time and strain rate, and the viscous-plastic model was defined by time-dependent analysis since it considered. Influence of various elements affecting the behavior of APJ was investigated, and it was confirmed that the time-dependent analysis showed better result closed to actual behavior than the time-independent analysis.

• Progress in Medical Physics
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• v.24 no.4
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• pp.290-294
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• 2013

Stereotactic Radiosurgery require high accuracy and precision of patient positioning and target localization. We evaluate the real time positioning accuracy of isocenter using optic guided patient positioning system, ExacTrac (BrainLab, Germany), during spinal radiosurgery procedure. The system is based on real time detect multiple body markers attached on the selected patient skin landmarks. And a custom designed patient positioning verification tool (PPVT) was used to check the patient alignment and correct the patient repositioning before radiosurgery. In this study, We investigate the selected 8 metastatic spinal tumor cases. All type of tumors commonly closed to thoracic spinal code. To evaluate the isocenter positioning, real time patient alignment and positioning monitoring was carried out for comparing the current 3-dimensional position of markers with those of an initial reference positions. For a selected patient case, we have check the isocenter positioning per every 20 millisecond for 45 seconds during spinal radiosurgery. In this study, real time average isocenter positioning translation were $0.07{\pm}0.17$ mm, $0.11{\pm}0.18$ mm, $0.13{\pm}0.26$ mm, and $0.20{\pm}0.37$ mm in the x (lateral), y (longitudinal), z (vertical) directions and mean spatial error, respectively. And body rotations were $0.14{\pm}0.07^{\circ}$, $0.11{\pm}0.07^{\circ}$, $0.03{\pm}0.04^{\circ}$ in longitudinal, lateral, table directions and mean body rotation $0.20{\pm}0.11^{\circ}$, respectively. In this study, the maximum mean deviation of real time isocenter positioning translation during spinal radiosurgery was acceptable accuracy clinically.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.72-77
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• 2010

The Incheon Bridge, which was opened to the traffic in October 2009, is an 18.4 km long sea-crossing bridge connecting the Incheon International Airport with the expressway networks around the Seoul metropolitan area by way of Songdo District of Incheon City. This bridge is an integration of several special featured bridges and the major part of the bridge consists of cable-stayed spans. This marine cable-stayed bridge has a main span of 800 m wide to cross the vessel navigation channel in and out of the Incheon Port. In waterways where ship collision is anticipated, bridges shall be designed to resist ship impact forces, and/or, adequately protected by ship impact protection (SIP) systems. For the Incheon Bridge, large diameter circular dolphins as SIP were made at 44 locations of the both side of the main span around the piers of the cable-stayed bridge span. This world's largest dolphin-type SIP system protects the bridge against the collision with 100,000 DWT tanker navigating the channel with speed of 10 knots. Diameter of the dolphin is up to 25 m. Vessel collision risk was assessed by probability based analysis with AASHTO Method-II. The annual frequency of bridge collapse through the risk analysis for 71,370 cases of the impact scenario was less than $0.5{\times}10^{-4}$ and satisfies design requirements. The dolphin is the circular sheet pile structure filled with crushed rock and closed at the top with a robust concrete cap. The structural design was performed with numerical analyses of which constitutional model was verified by the physical model experiment using the geo-centrifugal testing equipment. 3D non-linear finite element models were used to analyze the structural response and energy-dissipating capability of dolphins which were deeply embedded in the seabed. The dolphin structure secures external stability and internal stability for ordinary loads such as wave and current pressure. Considering failure mechanism, stability assessment was performed for the strength limit state and service limit state of the dolphins. The friction angle of the crushed stone as a filling material was reduced to $38^{\circ}$ considering the possibility of contracting behavior as the impact.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.466-477
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• 2012

This study aimed to develop the comprehensive indicators which can be used for evaluating greenhouse for tomato cultivation. To achieve this aim, the study developed the evaluation indicators composed of evaluation items, grades and criteria by extracting preliminary evaluation items through analyzing the related papers and preceding studies, and conducting Delphi survey on an expert group. During the three surveys, the questions of closed-ended type were given to a panel of 100 experts - professors related to tomato cultivation and facilities, researchers and farmers (practical users). As a result, the finally established evaluation indicators consist of 4 categories and 39 specific evaluation items. The 4 categories are the structural factor of greenhouse, equipment factor of greenhouse, cultivation factor, and infrastructure factor. These factors consist of specific evaluation items of 9, 15, 7 and 8, respectively. In addition, on 39 specific evaluation items, weighted values were calculated and grades and criteria were established by collecting opinions of the experts. The newly developed evaluation indicators through this study will play an important role in developing new greenhouse models, considering things that should be complemented preferentially regarding in-use facilities, and improving the efficiency of projects supported by the government.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.325-337
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• 2021

On the road and rail tunnels, the evacuation pathway and facilities such as smoke-control and fire suppression system are essential in tunnel fire. In the long twin tunnels, the cross-connection tunnel is usually designed to evacuate from the tunnel where the fire broke out to the other tunnel. In twin shield tunnels, the segment lining has to be demolished to construct the cross-connection tunnel. Considering the modern shield TBM is mostly the closed chamber type, the exposure of underground soil induced by removal of steel segment lining is the most danger construction step in the shield tunnel construction. This case study introduces the excavation method using the thrust of large steel pipe and reviews the measured data after the construction. The large steel pipe thrust method for the cross-connection tunnel can stabilize the excavated face with the two mechanisms. Firstly, the soil in front of excavated face is cylindrically pre-supported by the large steel pipe. Secondly, the excavated face is supported by the plugging effect caused by the soil pressed into the steel pipe. It was reviewed that the large steel pipe thrust method in the cross-connection tunnel is enough to secure the construct ability and stability in soil from the measurement results about the deformation and stress of steel pipe.

• Journal of Internet Computing and Services
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• v.22 no.2
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• pp.77-87
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• 2021

With the development of the Internet and personal computers, various and complex attacks begin to emerge. As the attacks become more complex, signature-based detection become difficult. It leads to the research on behavior-based log anomaly detection. Recent work utilizes deep learning to learn the order and it shows good performance. Despite its good performance, it does not provide any explanation for prediction. The lack of explanation can occur difficulty of finding contamination of data or the vulnerability of the model itself. As a result, the users lose their reliability of the model. To address this problem, this work proposes an explainable log anomaly detection system. In this study, log parsing is the first to proceed. Afterward, sequential rules are extracted by Bayesian posterior probability. As a result, the "If condition then results, post-probability" type rule set is extracted. If the sample is matched to the ruleset, it is normal, otherwise, it is an anomaly. We utilize HDFS datasets for the experiment, resulting in F1score 92.7% in test dataset.

• Journal of the Korean Society for Heat Treatment
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• v.32 no.5
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• pp.201-211
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• 2019

Low carbon steel (S20C steel) and SPCC steel sheet have been austenitic nitrided at $700^{\circ}C$ in a closed pit type furnace by changing the flow rate of ammonia gas and heat treating time. When the flow rate of ammonia gas was low, the concentration of residual ammonia appeared low and the hardness value of transformed surface layer was high. The depth of the surface layer, however, was shallow. With increasing the concentration of residual ammonia by raising up the ammonia gas flow, both the depth of the surface layer and the pore depth increased, while the maximum hardness of the surface layer decreased. By introducing a large amount of ammonia gas in a short time, a deep surface layer with minimal pores on the outermost surface was obtained. In this experiment, while maintaining 10~12% of residual ammonia, the flow rate of inlet ammonia gas, 7 liter/min, was introduced at $700^{\circ}C$ for 1 hour. In this condition, the thickness of the surface layer without pores appeared about $60{\mu}m$ in S20C steel and $30{\mu}m$ in SPCC steel plate. Injecting additional methane gas (carburizing gas) to this condition played a deteriorating effect due to promoting the formation of vertical pores in the surface layer. For $1^{st}$ transformed surface layer for S20C steel, maintaining 10~12% residual ammonia condition via austenitic nitriding process resulted in ${\varepsilon}$ phase with relatively high nitrogen concentration (just below 4.23 wt.%N) among the mixed phases of ${\varepsilon}+{\gamma}$. The ${\varepsilon}$ phase was formed a specific orientation perpendicular to the surface. For $2^{nd}$ transformed layer for S20C steel, ${\gamma}$ phase was rather dominant (just above 2.63 wt.%N). For SPCC steel sheet, there appeared three phases, ${\gamma}$, ${\alpha}(M)$ and weak ${\varepsilon}$ phase. The nitrogen concentration would be approximately 2.6 wt.% in these phases condition.