• Journal of Korean Society of Steel Construction
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• v.15 no.6 s.67
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• pp.701-709
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• 2003

The paper presented the seismic performance of T-stiffener moment connections for use in steel moment-resisting frames. The connections were strengthened by welding the vertical and horizontal clement of the T-stiffener to the beam flange and column f1ange. Finite clement analysis and experiments were conducted to determine the behavior of T-stiffener-reinforced connections. The results of the finite element analysis confirmed the effectiveness of the T-stiffener, whose horizontal element lengthened to mitigate local stress concentrations of the beam flange on the horizontal stiffener. Full-scale specimens were also tested cyclically to study hysteresis behavior. The main parameters used were the ratio of the T-stiffener to beam strength and the shape of the horizontal element. As the length of the horizontal element increased, the deformation capacity of the connections enhanced. Likewise, all specimens behaved according to the Ramberg-Osgood curve and showed stable hysteresis behavior.

• The korean journal of orthodontics
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• v.45 no.2
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• pp.59-65
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• 2015

Objective: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. Methods: A retrospective study of 34 patients (23 men, 11 women; mean age, $26.2{\pm}6.6years$) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. Results: The significant T0 to T1 mandibular changes occurred $-9.24{\pm}3.97mm$ horizontally. From T1 to T2, the mandible tended to move forward $1.22{\pm}2.02mm$, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). Conclusions: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.53-60
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• 2020

With the major advancement of vehicle-related technologies and services, the demands for the in/out-vehicle service expansion increase significantly. The key importance of the service expansion is to provide various vehicle-centric services in addition to improve the convenience and usability of users with connectivity. Recently, Internet of Things (IoT) gains major attention for small device connectivity and service, and it widens its area to other industries including automotive to advance and diversify its services. In this paper, we investigated the technical direction of the IoT service with the analysis of IoT technologies in the perspective of the vehicle. At first, we analyzed the vehicle and IoT services in each so that we are able to suggest the service design guideline and consideration to release integrated services between vehicle and IoT. Also, we reviewed the cases of few vehicle and home IoT integration services for the major insights and future direction of the integration services.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.2
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• pp.59-66
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• 2018

Android Things is an Android-based platform running in Google's IoT environment. Android smartphones require permissions from application users to use certain features, but in the case of Android Things, there is no display to send request notifications to users. Therefore Does not make a request to use the permissions and automatically accepts the permissions from the system. If the privilege is used indiscriminately, malicious behavior such as system failure or leakage of personal information can be performed by a function which is not related to the function originally. Therefore, By monitoring the privileges that a device uses in an Android-based IoT system, users can proactively respond to security threats that can arise through unauthorized use of the IoT system. This paper proposes a system that manages the rights currently being used by IoT devices in the Android Things based IoT environment, so that Android-based IoT devices can cope with irrelevant use of rights.

• Journal of Digital Convergence
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• v.13 no.2
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• pp.291-297
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• 2015

The basic idea of IoT(Internet of Things) is interconnection and cooperation with a variety of things in real life such as Radio-Frequency Identification(RFID) tags, sensors, mobile phone, etc, through internet. IoT technologies which applied to these fields consist of sensor network technology and middleware, application. Currently, IoT technology is applied to various fields such as health care, home care, automotive, transportation, construction, agriculture, environment, food, and etc, based on its technologies. This paper focuses on discussion of the IoT development trend in game field. In order to achieve this purpose, first, the IoT technologies for game development based on sensor network technology and middleware, application is mentioned. Second, covers serious game and gamification that is expected to be a growing that is expected to be a growing, by applying IoT technologies to the game field. It can help for game developers by using IoT technologies.

• Journal of the Korean Statistical Society
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• v.17 no.1
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• pp.30-45
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• 1988

Let ${X(t) : 0 \leq t < \infty}$ be a real-valued process with stationary independent increments. In this paper, we obtain necesary and sufficint condition for there to exist a positive, nondecreasing function $\beta(t)$ so that $0 < lim sup $\mid$X(t)$\mid$/\beta(t) < \infty$ a.s. both as t tends to zero and infinity. When no such $\beta(t)$ exists we give a simple integral test for whether $lim sup $\mid$X(t)$\mid$/\beta(t)$ is zero or infinity for a given $\beta(t)$.

• Proceedings of the Technology Innovation Conference
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• 2005.06a
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• pp.140-158
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• 2005

Science & Technology (S&T) is the most important thing to attain competitiveness in the 21st century. Our traditional S&T policies have been focused on hardware infra structure. But, we should consider soft infra of S&T to enhance welfare development of S&T personnel. S&T should be had a correct understanding method of the creation for S&T culture. It implies that S&T policy in the 21st century should consider non-material factors which include social, human, environment and culture. Under this background. This paper defines the concept of welfare of S&T personnel. Also this paper deals with the change of S&T policy of Korea and analyzes the characteristic of each phase. This paper argues that all actors (for example S&T personnel, corporate using S&T, public) should participate in the process of S&T innovation since the 21st century is the generation of popularization of S&T. The purpose of this paper is to suggest a few methods of welfare improvement of S&T personnel to reinforce soft infra structure of S&T.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.779-780
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• 2015

As IoT becomes a main technology of the age, many IoT products have developed and are being developed now. By using open-source hardware "Arduino"and open-source IoT platform "Temboo" to analize CAN signal from vehicle and make vehicle IoT environment to analize and use it through the mobile phone, figured out the way to develop the IoT environment with low cost. Also suggest the way to solve problems and improove.

• Journal of the Korean Institute of Gas
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• v.25 no.5
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• pp.70-77
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• 2021

As IoT technology develops along with the 4th industrial revolution, gas safety products to which IoT technology is applied are being developed. However, since the gas safety system was not allowed, system improvement and operation reliability test for IoT gas safety products are required. This thesis researches IoT fuse cock and smart multi-function meter among IoT gas safety products, and analyzes the empirical data of IoT fuse cock to secure operational reliability data, thereby becoming a leader in IoT gas safety products. It aims to develop gas barrier technology one step further through various test evaluations and methods in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.394-400
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• 2004

To investigate the efficacy of alternatives to antibiotics, the present study was conducted to compare the effects of antibiotic, lactic acid, a blend of commercial essential oils (EOs) and EOs in combination with lactic acid on growth performance and the functional activity of the gut in broiler chickens. A total of 168 broiler chickens were given the basal diet supplemented with 10 ppm colistin (T1), 0.1% lactic acid (T2), 25 ppm EOs (T3), 25 ppm EOs+0.1% lactic acid (T4), 50 ppm EOs (T5) or 50 ppm EOs+0.1% lactic acid (T6) in the period 3 to 35 days of age. As a result, the broiler chickens assigned to T4 group throughout the experimental period had apparently (p<0.05) greater body weight and total gain than these assigned to T1, T2, T3 and T5 groups. However, there was no difference in growth performance among the birds fed the diets supplemented with antibiotic (T1), lactic acid (T2) and EOs (T3 and T5) alone. The weights of digestive organs and the number of lactobacilli and E. coli in the lower ileum were not affected by dietary treatments. Total trypsin activity was significantly (p<0.05) greater in T4 than T1, T2, T3 and T5 groups. Total and specific pancreatic $\alpha$-amylase activities were significantly (p<0.05) enhanced in the broiler chickens fed T4 diet compared with these fed T1, T2 and T3 diets. However, there were no differences in growth performance and digestive enzyme activities including pancreatic trypsin and $\alpha$-amylase between T4 and T6 groups fed the diets supplemented with either low or high EOs levels in combination of lactic acid. In conclusion, a blend of commercial EOs combined with lactic acid showed significant increases in digestive enzyme activities of the pancreas and intestinal mucosa, leading to increase in growth performance.