• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.352-357
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• 1993

The purpose of the present study was to evaluate and compare the periodontal conditions of distally extending cantilever bridges(CB) and removable patial dentures(RPD). 78 patients treated with removable partial dentures were divided into 2 groups; bilateral free-ending (type 1) and unilateral free-ending(type 2). 43 patients treated with distally extending cantilever bridges were divided into 4 groups according to position of missing molars and number of including abutment tooth (or teeth) (type 1-4). Prosthodontic status of the abutment teeth were assessed; overcontoured crown, overhanged margin, embrasure closure, and others. Their Periodonted status were assessed with Plaque Index Gingial Index(GI) Sulcus bleedy Index (SBI), Tooth mobility(TM) & Posher depth(PPD). 35.9% of RPD group and 38.1 of CB grouphad disconfort on mastication with prosthetics. 16.7% of RPD group and 6.1% of CB group showed on opposing sites. Overhanged margins were 58.3% for RPD group and 86.6% for GB group. 45.5% of RPD group and 72% of CB group had embrasure closure on the abutment teeth. 30.5% of GB group had oversized pontic. Gb group showed much higher clinical parameters than RPD groups, but statistically not significant. Type 2 of RPD group showed lower GI and SBI, but statistically not significant. Type 3 of CB group showed the highest GI and SBI and type 2 showed the highest tooth mobility, but there is no differences between the same type of groups. In conclusion, only minor differences in periodontal conditions were recorded in RPD and CB group.

• Journal of Advanced Navigation Technology
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• v.26 no.3
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• pp.144-160
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• 2022

Research on urban air mobility (UAM) is being actively conducted as a method of next-generation transportation. eVTOL, an airplane to be used for urban air mobility, is classified into a complex type, a tilt rotor type, a tilt wing type, a tilt duct fan type, and a multicopter type according to the propulsion method. In this study, conceptual design was performed for the next generation eVTOL of the new tilt rotor type in accordance with the existing design requirements. The aerodynamic analysis programs of OpenVSP and XFLR5 were used to perform aerodynamic analysis. The power required for each flight mission stage was calculated, the battery and motor were selected accordingly, and MTOW (Maximum Take-Off Weight) was predicted by estimating the weight of each component.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.281-287
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• 2024

In general, design education related to transportation has been recognized as a department specialized in transportation design or as an area of detailed transportation majors within industrial design majors. However, as technological, social, and environmental factors change, the concept of mobility and the ecosystem related to the mobility industry are diversifying, and accordingly, the category of mobility-related design is expanding further. Based on this background, this study is not a mobility design major, but it aims to find implications by analyzing the trend and type of topic selection related to the mobility ecosystem among the last five years of graduation design topics conducted in the design engineering major. As a result of the study, of a total of 131 graduation design works conducted over the past five years, about 30 works were highly related to mobility, and their types were very diverse. In conclusion, it was confirmed that the change and expansion of the mobility ecosystem expanding from products to services and systems were also reflected in the selection of graduation works in that various topics approached from user-centered and user experience were proposed and made into works.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.699-705
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• 2005

In order to identify the speciation of As and trace elements which are contained weathered waste rocks on the abandoned Jangpoong Cu mine area, five fraction sequential extraction was carried out. Concentrations of the extraction solutions which were acquaired each fraction were mesured by ICP-AES. Mineral characters of weathered waste rocks were determinated by XRD. The weathered waste rocks could divide into two types (Type I and type II). Type land type II weathered waste rocks are mainly composed of a quartz and a calcite, respectively. The most dominant speciation of As, Co and Fe is residual phase. Most of the speciation of Cd, Mn and Zn is residual phase for type I and Fe-Mn oxide phase for type II. In case of Cu, residual phase is predominant in type I and sulfide is predominet in type II. The most dominant speciation of Pb for type I and type II is associated with the residual phase and Fe-Mn oxide phase, respectively. At pH 4-7 range, the order of relative mobility considers Zn>Cu>Cd>Pb>Co>AS in type I, and Cd>Cu>Zn>Pb>As>Co in type II.

• Journal of the Korean Society of Physical Medicine
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• v.5 no.3
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• pp.363-373
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• 2010

Purpose : The purpose of this study was to compare differences in thoracolumbar ranges of motions by comparing ratios among 4 type diagnosis for patient with chronic low back pain. Methods : The subjects were 58 chronic low back pain patients. A motion analysis program (Global Postural System) was used after photography for posture measurement. To analyze differences in mobility percentages and ratios of thoracolumbar ranges of motion, one-way ANOVA was used. Results : Regional difference spinal posture and movement were found to diagnosis patients with chronic low back pain. Comparison of thoracolumbar ranges of motion revealed significant differences in the thoracic region during forward-bending of the trunk (p<.05). In the upper thoracic region, the herniated intervertebral lumbar disc (HILD) group was significantly larger than the spinal stenosis/herniated intervertebral lumbar disc (SS/HILD) group (p<.05). In the lower thoracic region, chronic sprains (CS) were significantly greater than in the spinal stenosis (SS) group and in the (SS/HJLD) group (p<.05). Comparative analysis of thoracic/lumbar mobility ratio showed the CS group's ratio during forward bending was largest: 1.66, while the HILD group's ratio was smallest: 84 a significant difference between the two groups (p<.01). Diagnosis was not associated with difference in thoracolumbar backward-bending range of motion (p>.05). Conclusion : Theses results indicate the clinical efficacy of diagnosing for chronic low back pain by evaluating spinal mobility.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.243-248
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• 2014

The demand for messenger service goes on growing rapidly with widespread use of smartphones. Generally, the smartphone messenger provides group communication functions in which users can make the group and communicate with each other. In the mobile meeting, the attendees can participate in the meeting with use of smartphone messengers wherever they are. To make the mobile meeting put to practical use, the mobility and privacy should be ensured to attendees. To satisfy the mobility requirement, the user which is not belong to the group members should not be able to participate in the meeting. To ensure the privacy requirement, the attendees should have not to repudiate the meeting results. In this study, the mobile meeting authentication scheme is proposed which provides mobility and privacy. The proposed scheme consists of meeting group creation, group key generation, group signature and verification protocols. All attendees should have to participate in the signature verification because it is based on the challenge-response type protocol. Thus, it's not possible to collude with malicious attendees to change the meeting results.

• Fashion & Textile Research Journal
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• v.26 no.1
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• pp.123-136
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• 2024

This study aimed to assess the mobility and thermal comfort of personal protective equipment (PPE) among female healthcare workers, taking into account wearers' physique and PPE protection levels. A total of 16 participants (age: 26.3 ± 8.3 y, height: 161.5 ± 7.3 cm, body weight: 57.1 ± 11.0 kg, BMI: 21.9 ± 3.6), representing diverse body types, underwent four PPE conditions: L (Low_Plastic gown ensemble), M (Medium_Tyvek 400), H (High_Tyvek 800J with Powered Air Purifying Respirator [PAPR]), and E (Extremely high_Tychem 2000 with PAPR, Bib apron, and Chemical-resistant gloves). The mobility protocol consisted of 10 different tasks in addition to donning and doffing. The 10 tasks were repeated twice at an air temperature of 24.3 ± 0.1℃, 59±4%RH. Findings revealed a disproportionate relationship between PPE protection and wearer discomfort. Significant differences in clothing microclimate and total sweat rate were observed between the lowest (L) and highest (E) protection levels (p < 0.01), while distinctions among medium levels were inconclusive. Subjective evaluations favored conditions H and L over M and E (p < 0.05), indicating reduced heat, and humidity, increased comfort, and lower exertion. Instances of mobility discomfort, specially in the small body type group, underscored the need for a suitable PPE size system for Korean adult female medical workers. Furthermore, enhancements in gloves, shoe cover, and PAPR hood designs are essential for improving ease of movement and preventing hindrance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.5
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• pp.885-896
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• 2013

MTC(Machine Type Communications), providing a variety of services anytime and anywhere by connecting the cellular network to the machine and things without human intervention, is being considered as a major challenge of the next-generation communications. Currently, When a massive MTC devices simultaneously connect to the network, each MTC device needs an independent access authentication process. Because of this process, authentication signaling congestion and overload problems will cause in LTE-Advanced. In this paper, we propose a group-based authentication protocol and a key management protocol. For managing the MTC devices as group units, the proposed protocol elects a group leader and authentications only once with the core network. After the authentication is completed, a group leader manages the rest members and MME(Mobility Management Entity) by constructing a binary tree. Finally, the propose protocol analysis show that the proposed protocol not only can reduces the authentication signaling which generated in between the MTC devices and the core network but also can manages the MTC devices, efficiently.

• The Journal of Bigdata
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• v.7 no.2
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• pp.235-244
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• 2022

The rental history data of public bicycles in Seoul were analyzed to examine how pandemic phenomena such as COVID-19 caused changes in people's micro mobility. Data for 2019 and 2021 were compared and analyzed by dividing them before and after COVID-19. Data were collected from public data portal sites, and data marts were created for in-depth analysis. In order to compare the changes in the two periods, the riding direction type dimension and the rental station type dimension were added, and the derived variables (rotation rate per unit, riding speed) were newly created. There is no significant difference in the average rental time before and after COVID-19, but the average rental distance and average usage speed decreased. Even in the mobility of Ttareungi, you can see the slow rhythm of daily life. On weekdays, the usage rate was the highest during commuting hours even before COVID-19, but it increased rapidly after COVID-19. It can be interpreted that people who are concerned about infection prefer Ttareungi to village buses as a means of micro-mobility. The results of data mart-based visualization and analysis proposed in this study will be able to provide insight into public bicycle operation and policy development. In future studies, it is necessary to combine SNS data such as Twitter and Instagram with public bicycle rental history data. It is expected that the value of related research can be improved by examining the behavior of bike users in various places.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.286-289
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• 2001

Single phase CuGaS$_2$ thin film with the highest diffraction peak of (112) at diffraction angle (2$\theta$) of 28.8$^{\circ}$ was made at substrate temperature of 7$0^{\circ}C$, annealing temperature of 35$0^{\circ}C$ and annealing time of 60 min. And second highest (204) peak was shown at diffraction angle (2$\theta$) of 49.1$^{\circ}$. Lattice constant of a and c of that CuGaS$_2$ thin film was 5.37 $\AA$ and 10.54 $\AA$ respectively. The greatest grain size of the thin film was about 1${\mu}{\textrm}{m}$. The (112) peak of single phase of CuGaS$_2$ thin film at annealing temperature of 35$0^{\circ}C$ with excess S supply was appeared with a little higher about 10 % than that of no exces S supply And the resistivity, mobility and hole density at room temperature of p-type CuGaS$_2$ thin film with best crystalline was 1.4 $\Omega$cm, 15 cm2/V . sec and 2.9$\times$10$^{17}$ cm$^{-3}$ respectively. It was known that carrier concentration had considerable effect than mobility on variety of resistivity of the fabricated CuGaS$_2$ thin film, and the polycrystalline CuGaS$_2$ thin films were made at these conditions were all p-type.