• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.797-804
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• 2006

A development of regression model for asphalt concrete pavements using Falling Weight Deflectometer deflections is presented in this paper. A backcalculation program based on layered elastic theory was used to generate the synthetic modulus database, which was used to generate 95% confidence intervals of modulus in each layer. Using deflection basins of FWD data used in developing this procedure were collected from Pavement Management System in flexible pavements. Assumptions of back-calculation are that one is 3 layered flexible pavement structure and another is depth to bedrock is finite. It is found that difference of between 95% confidence intervals and modulus ranges of other papers does not exist. So, the data of 95% confidence intervals in each layer was used to develop multiple regression models. Multiple regression equations of each layer were established by SPSS, package of Statics analysis. These models were proved by regression diagnostics, which include case analysis, multi-collinearity analysis, influence diagnostics and analysis of variance. And these models have higher degree of coefficient of determination than 0.75. So this models were applied to predict modulus of domestic asphalt concrete pavement at FWD field test.

• Journal of the Korean Applied Science and Technology
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• v.41 no.3
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• pp.586-598
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• 2024

This study aimed to improve the service quality of the ski rental industry and provide basic data to satisfy customers' needs by investigating how the service quality of ski rental shops affects consumers' perceived value and purchasing behavior. Therefore, a survey was conducted on users visiting rental shops at six ski resorts in Korea (High1 Resort, Yongpyeong Resort, Jisan Resort, Gonjiam Resort, Phoenix Park, and Welli Hilli). The collected data was conducted by using SPSS (B. 25.0) program, visual factors analysis, and multivariate distributed analysis, simple, simple and multivariate variance analysis, simple and multivariate analysis. The results derived from this study are as follows. First, it was found that the service quality of ski resort rental shops had a significant effect on perceived value in the order of convenience, empathy, service, and facility environment. Second, it was found that the perceived value of purchasing behavior of purchase behavior and recommendations. Third, it was found that the service quality of ski resort rental shops had a significant effect on purchase intention and recommendation intention of purchase behavior in the order of empathy, facility environment, convenience, and service.

• The Korean Journal of Petroleum Geology
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• v.5 no.1_2 s.6
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• pp.9-15
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• 1997

The study area is located in the Central Bransfield Basin, Antarctica. To analyze the morphology of seafloor, structure of basement, and seismic stratigraphy of the sedimentary layers, we have acquired, processed, and interpreted the multi-channel seismic data. The northwest-southeastern back-arc extension dramatically changes seafloor morphology, volcanic and fault distribution, and basin structure along the spreading ridges. The northern continental shelf shows a narrow, steep topography. In contrast, the continental shelf or slope in the south, which is connected to the Antarctic Peninsula, has a gentle gradient. Volcanic activities resulted in the formation of large volcanos and basement highs near the spreading center, and small-scale volcanic diapirs on the shelf. A very long, continuous normal fault characterizes the northern shelf, whereas several basinward synthetic faults probably detach into the master fault in the south. Four transfer faults, the northwest-southeastern deep-parallel structures, controlled the complex distributions of the volcanos, normal faults, depocenters, and possibly hydrocarbon provinces in the study area. They have also deformed the basement structure and depositional pattern. Even though the Bransfield Basin was believed to be formed in the Late Cenozoic (about 4 Ma), the hydrocarbon potential may be very high due to thick sediment accumulation, high organic contents, high heat flow resulted from the active tectonics, and adequate traps.

• Geophysics and Geophysical Exploration
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• v.24 no.4
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• pp.194-201
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• 2021

Induced polarization (IP) effect is known to be caused by electrochemical phenomena at interface between minerals and pore water. Spectral induced polarization (SIP) method is an electrical survey to localize subsurface IP anomalies while injecting alternating currents of multiple frequencies into the ground. This method was effectively applied to mineral exploration of various ore deposits. Titanomagnetite ores were being produced by a mining company located in Gonamsan area, Gwanin-myeon, Pocheon-si, Gyeonggi-do, South Korea. Because the ores contain more than 0.4 w% vanadium, the ore deposit is called as Gwanin vanadiferous titanomagnetite (VTM) deposit. The vanadium is the most important of materials in production of vanadium redox flow batteries, which can be appropriately used for large-scale energy storage system. Systematic mineral exploration was conducted to identify presence of hidden VTM orebodies and estimate their potential resources. In geophysical exploration, laboratory geophysical measurement of rock samples is helpful to generate reliable property models from field survey data. Therefore, we performed laboratory SIP data of the rocks from the Gwanin VTM deposit to understand SIP characteristics between ores and host rocks and then demonstrate the applicability of this method for the mineral exploration. Both phase and resistivity spectra of the ores sampled from underground outcrop and drilling cores were different of those of the host rocks consisting of monzodiorite and quartz monzodiorite. Because the phase and resistivity at frequencies below 100 Hz are mainly dependent on the SIP characteristics of the rocks, we calculated mean values of the ores and the host rocks. The average phase values at 0.1 Hz were ores: -369 mrad and host rocks: -39 mrad. The average resistivity values at 0.1 Hz were ores: 16 Ωm and host rocks: 2,623 Ωm. Because the SIP characteristics of the ores were different of those of the host rocks, we considered that the SIP survey is effective for the mineral exploration in vanadiferous titanomagnetite deposits and the SIP characteristics are useful for interpreting field survey data.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.252-263
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• 1984

This study was conducted to find out the effect of thyroid function on Hypophysis, and serum FSH and LH concentrations in female rats. One hundred and forty-four female rats (wistar-imamichi albino rats) of 25 days old were divided into 4 groups; thyroidectomy (Thx.) propylthiouracil (PTU), thyroxine (Thyro.) and control (Cont.) groups. Thirty-six heads of rats were arranged to each group. The thyroid glands of the thyroidectomized groups were removed by surgery. The PTU treated groups were drunk the propylthiouracil solution of 0.05% and the thyroxine treated groups were administered subcutaneously with $30{\mu}g$ per 100 g body weight on 3 days intervals. Every 6 heads of rats in each group were sacrificed at 1, 2, 3, 4, 5, and 6 weeks after treatment with time elapse for investigating the weights and histological changes of hypophysis. The results obtained were as follows : 1. The weights of hypophysis at all treated groups were higher than control group, but significantly increased from 3 to 5 weeks. The significance was not recognized between Thyro. and control groups, and Thx. and PTU groups. 2. In the histological changes of hypophysis, eosinophils atrophied from 4 weeks after treatment in Thx. and PTU groups, and basophils showed hypertrophy and hyperplasia from 2 weeks after treatment and thereafter this tendency was more serious showing vacuolization from 4 weeks after treatment. In Thyro. treated group, eosinophils showed slight hypertrophy and basophils atrophied from 5 weeks after treatment but the group showed the similar histological changes in comparison with the control group. 3. The changes of the concentrations of serum FSH at all observation times were significantly recognized among all observation groups. The concentrations in True and PTU groups were significantly lower than those in control group, but those in Thyro. group were significantly higher than those in control group. 4. The changes of the concentrations of serum LH in all treated groups were significantly lower than those in control group. The significance was not recognized between True and PTU group, and Thyro. and control groups.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.5
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• pp.492-501
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• 2007

Coastal disasters have become one of the most important issues in every coastal country. In Korea, coastal disasters such as storm surge, sea level rise and extreme weather have placed many coastal regions in danger of being exposed or damaged during subsequent storms and gradual shoreline retreat. A storm surge is an onshore gush of water associated with a tow pressure weather system, typically in typhoon season. However, it is very difficult to predict storm surge height and inundation due to the irregularity of the course and intensity of a typhoon. To provide a new scheme of typhoon damage prediction model, the scenario which changes the central pressure, the maximum wind radius, the track and the proceeding speed by corresponding previous typhoon database, was composed. The virtual typhoon scenario database was constructed with individual scenario simulation and evaluation, in which it extracted the result from the scenario database of information of the hereafter typhoon and information due to climate change. This virtual typhoon scenario database will apply damage prediction information about a typhoon. This study performed construction and analysis of the simulation system with the storm surge/coastal inundation model at Masan coastal areas, and applied method for predicting using the scenario of the storm surge.

• Journal of Hospice and Palliative Care
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• v.20 no.4
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• pp.226-234
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• 2017

Purpose: With the implementation of the Act on Life Sustaining Treatment, hospice-palliative care will be extended to non-cancer diseases including the acquired immunodeficiency syndrome (AIDS). However, there are concerns about negative perceptions and prejudice toward AIDS patients. The purpose of this study was to investigate factors related with willingness to volunteer (WV) for patients with end-stage AIDS among hospice volunteers. Methods: Participants were 326 hospice volunteers from 19 institutions. A self-administered questionnaire was employed to investigate the participants' WV for end-stage AIDS patients, and the questions were answered using an 11-point rating scale. Demographics, volunteer activity, satisfaction with hospice volunteering, knowledge of AIDS, and attitudes towards AIDS patients (i.e., fear AIDS patients, negative attitude towards AIDS patients, personal stigmatization and stigmatizing attitude) were also investigated. A multiple regression analysis was performed to examine factors associated with WV for patients with end-stage AIDS. Results: WV for patients with end-stage AIDS was 2.82 points lower than that for cancer patients (P<0.001). The multiple regression analysis showed that the higher the level of satisfaction with hospice volunteering (P=0.002) and the lower the level of "personal stigmatization" (P<0.001), participants showed greater WV for end-stage AIDS patients. Conclusion: The level of satisfaction with hospice volunteering and "personal stigmatization" were factors associated with participants' WV for patients with end-stage AIDS.

• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.39-44
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• 1999

High-resolution images are drawn from existing seismic data which were originally obtained by Korea Ocean Research & Development Institute (KORDI) during 1994-1997 for deep seismic studies on the East Sea of Korea. These images are analyzed for mapping Quaternary faults and near-bottom gas pockets. First 12 channels are selected from shot gathers for reprocessing. The processing sequence adopted for high-resolution seismic images comprises data copy, trace editing, true amplitude recovery, common-midpoint sorting, initial muting, prestack deconvolution, bandpass filtering, stacking, highpass filtering, poststack deconvolution, f-x migration, and automatic gain control (AGC). Among these processing steps, predictive deconvolution, highpass filtering, and short window AGC are the most significant in enhancement of resolution. More than 200 Quaternanry faults are interpreted on the migrated sections in the shallow depths beneath the seafloor. Although numerous faults are found mostly at the western continental slope and boundaries of the Ulleung Basin, significant amount of the faults are also indicated within the basin. Many of these faults are believed to be formed with reactivation of basement, from geotectonic activities including volcanism, and often originated in Tertiary, indicating that the tectonic regime of the East Sea might be unstable. Existence of shallow gas pockets casts real hazardous warnings to deep-sea drillings and/or to underwater constructions such as inter-island cables and gas pipelines. On the other hand, discovery of these gas pockets heightens the interests in developing natural resources in the East Sea. Reprocessed seismic sections, however, show no typical seismic characteristics for gas hydrates such as bottom-simulating reflectors in the western continental slope and ocean floor.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.633-638
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• 2017

The amount of radioactive waste has been rapidly increased with development of radiation treatment in medical field. Recently, it has been a common practice to use I-131 for thyroid cancer, F-18 for PET/CT and Tc-99m for diagnosis of nuclear medicine. All the wastes concerned have been disposed of by means of the self-disposal method, for example incineration, after storage enough to decay less than clearance level. IAEA proposed criteria for clearance level of waste which depends on the individual ($10{\mu}Sv/y$) and collective dose (1 man-Sv/y), and concentration of each nuclide (IAEA Safety Series No 111-P-1.1, 1992 and IAEA RS-G-1.7, 2004). In this study, specific radioactivity of radioactive waste contaminated with Re-186 was measured to confirm whether it meets the clearance level. Re-186 has long half life of 3.8 days relatively and emits beta and gamma radiation, therefore it can be applied in treatment and imaging purposes. The specific radioactivity of contaminated gloves weared by radiation workers was measured by MCA(Multi-channel Analyzer) which was calibrated by reference materials in accordance with the measuring procedure. As a result, comparison evaluation of decay storage period between the half-life which was calculated by attenuation curve based on real measurement and physical half-life was considered, and it is showed that the physical half-life is longer than induced half-life. Therefore, the storage period of radioactive waste for self-disposal may be curtailed in case of application of induced half-life. The result of this study will be proposed as ISO standard.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.10
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• pp.493-501
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• 2007

The imprecise real-time system provides flexibility in scheduling time-critical tasks. Most scheduling problems of satisfying both 0/1 constraint and timing constraints, while the total error is minimized, are NP-complete when the optional tasks have arbitrary processing times. Liu suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on uniprocessors for minimizing the total error. Song et at suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on multiprocessors for minimizing the total error. But, these algorithms are all off-line algorithms. In the online scheduling, the NORA algorithm can find a schedule with the minimum total error for the imprecise online task system. In NORA algorithm, EDF strategy is adopted in the optional scheduling. On the other hand, for the task system with 0/1 constraint, EDF_Scheduling may not be optimal in the sense that the total error is minimized. Furthermore, when the optional tasks are scheduled in the ascending order of their required processing times, NORA algorithm which EDF strategy is adopted may not produce minimum total error. Therefore, in this paper, an online algorithm is proposed to minimize total error for the imprecise task system with 0/1 constraint. Then, to compare the performance between the proposed algorithm and NORA algorithm, a series of experiments are performed. As a conseqence of the performance comparison between two algorithms, it has been concluded that the proposed algorithm can produce similar total error to NORA algorithm when the optional tasks are scheduled in the random order of their required processing times but, the proposed algorithm can produce less total error than NORA algorithm especially when the optional tasks are scheduled in the ascending order of their required processing times.