• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.365-372
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• 1999

The plane deformation and spatial seepage(PDSS) analysis was developed to consider 3D flow of excess pore water as well as plane deformation of ground. Here is newly developed an equivalent model for PDSS analysis, which was the purpose to reduce number of finite elements and to take the effects of smear and well resistance into consideration. As the result of PDSS analysis with applying the new model, it is showed that the settlement-tin e relationship by PDSS agrees well with those of Plane strain(PS) and axisymmetric analyses, irrespective of existence of untreated layer. And the excess pore pressure distribution by PDSS is relatively agreed with that of axisymmetric analysis, not with that of PS.

• Safety and Health at Work
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• v.10 no.4
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• pp.461-469
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• 2019

Background: Collisions involving workers and mobile machines continue to be a major concern in underground coal mines. Over the last 30 years, these collisions have resulted in numerous injuries and fatalities. Recently, the Mine Safety and Health Administration (MSHA) proposed a rule that would require mines to equip mobile machines with proximity detection systems (PDSs) (systems designed for automated collision avoidance). Even though this regulation has not been enacted, some mines have installed PDSs on their scoops and hauling machines. However, early implementation of PDSs has introduced a variety of safety concerns. Past findings show that workers' trust can affect technology integration and influence unsafe use of automated technologies. Methods: Using a mixed-methods approach, the present study explores the effect that factors such as mine of employment, age, experience, and system type have on workers' trust in PDSs for mobile machines. The study also explores how workers are trained on PDSs and how this training influences trust. Results: The study resulted in three major findings. First, the mine of employment had a significant influence on workers' trust in mobile PDSs. Second, hands-on and classroom training was the most common types of training. Finally, over 70% of workers are trained on the system by the mine compared with 36% trained by the system manufacturer. Conclusion: The influence of workers' mine of employment on trust in PDSs may indicate that practitioners and researchers may need to give the organizational and physical characteristics of each mine careful consideration to ensure safe integration of automated systems.

• ETRI Journal
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• v.38 no.3
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• pp.425-434
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• 2016

A novel average magnitude difference function (AMDF)-based pitch detection scheme (PDS) is proposed to achieve better performance in speech quality. A performance evaluation of the proposed PDS is carried out through both a simulation and a real-time implementation of a speech analysis-synthesis system. The parameters used to compare the performance of the proposed PDS with that of PDSs that are based on either a cepstrum, an autocorrelation function (ACF), an AMDF, or circular AMDF (CAMDF) methods are as follows: percentage gross pitch error (%GPE); a subjective listening test; an objective speech quality assessment; a speech intelligibility test; a synthesized speech waveform; computation time; and memory consumption. The proposed PDS results in lower %GPE and better synthesized speech quality and intelligibility for different speech signals as compared to the cepstrum-, ACF-, AMDF-, and CAMDF-based PDSs. The computational time of the proposed PDS is also less than that for the cepstrum-, ACF-, and CAMDF-based PDSs. Moreover, the total memory consumed by the proposed PDS is less than that for the ACF- and cepstrum-based PDSs.

• Clinical and Experimental Pediatrics
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• v.54 no.1
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• pp.29-35
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• 2011

Purpose: Korean adolescents have severe nighttime sleep deprivation and daytime sleepiness because of their competitive educational environment. However, daytime sleep patterns and sleepiness have never been studied using age-specific methods, such as the pediatric daytime sleepiness scale (PDSS). We surveyed the daytime sleepiness of Korean adolescents using a Korean translation of the PDSS. Methods: We distributed the 27-item questionnaire, including the PDSS and questions related to sleep pattern, sleep satisfaction, and emotional state, to 3,370 students in grades 5-12. Results: The amount of nighttime sleep decreased significantly with increasing age. During weekday nights, $5-6^{th}$ graders slept for $7.95{\pm}1.05h$, $7-9^{th}$ graders for $7.57{\pm}1.05h$, and $10-12^{th}$ graders for $5.78{\pm}1.13h$. However, the total amounts of combined daytime and nighttime sleep during weekdays were somewhat greater, $8.15{\pm}1.12h$ for $5-6^{th}$ graders, $8.17{\pm}1.20h$ for $7-9^{th}$ graders, and $6.87{\pm}1.40h$ for $10-12^{th}$ graders. PDSS scores increased with age, $11.89{\pm}5.56$ for $5-6^{th}$ graders, $16.57{\pm}5.57$ for $7-9^{th}$ graders, and $17.71{\pm}5.24$ for $10-12^{th}$ graders. Higher PDSS scores were positively correlated with poor school performance and emotional instability. Conclusion: Korean teenagers sleep to an unusual extent during the day because of nighttime sleep deprivation. This negatively affects school performance and emotional stability. A Korean translation of the PDSS was effective in evaluating the severity of daytime sleepiness and assessing the emotional state and school performance of Korean teenagers.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.544-551
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• 2020

Background: Previous studies have shown the insecticidal efficacy of ginsenosides. In the present study, we aimed to investigate the metabolic mechanism related to the inhibitory effect of panaxadiol saponins (PDSs) against the Asian corn borer Ostrinia furnacalis (Guenee). Methods: Third instar larvae of O. furnacalis were fed normal diets with different concentrations of PDSs for 4 days. The consumption index, relative growth rate, approximate digestibility, and conversion of ingested and digested food were recorded. A targeted gas chromatographye-mass spectrometry assay was performed to detect the profiles of amino acids, fatty acids, and carbohydrates in larvae of O. furnacalis. In addition, the activity of detoxification-related enzymes was determined. Results and Conclusions: PDSs decreased the consumption index, relative growth rate, approximate digestibility, and conversion of ingested and digested food in the 3rd instar larvae of O. furnacalis in a dose-dependent manner. PDSs decreased 15 free amino acids, 16 free fatty acids, and 5 carbohydrates and increased the levels of palmitoleic acid, palmitic acid, and 9-octadecenoic acid in the 3rd instar larvae. The activity of detoxification-related enzymes, such as acetylcholinesterase, glutathione S-transferase, cytochrome P450, carboxylesterase, trehalase, acid phosphatase, and alkaline phosphatase, was reduced in a dose-dependent manner in the 3rd instar larvae exposed to PDSs. These data confirmed the inhibitory effect of PDSs against growth, food utilization, and detoxification in the 3rd instar larvae of O. furnacalis and the potential for using PDSs as an efficient tool for insect pest management for O. furnacalis larvae.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.207-209
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• 2011

Numerous reports show that alternative project delivery systems (PDSs) such as design-build (DB), construction management at risk (CMR), and design-build-maintain (DBM) are increasingly used in many countries. This study compared characteristics of each PDS (design-bid-build (DBB), DB, CMR, or DBM) by analyzing quantitative data from 9 research articles. In order to compare characteristics between DBB and alternative PDSs, the study is based on principal 3 factors - Time, Cost, and Quality. DB shows the best performance in the time part and also the cost performance depending on facility type and project size. The performance of quality has minor difference among different PDSs. These results support the fact that using an appropriate PDS by the characteristic of a project makes high value of efficiency and productivity.

• Anxiety and mood
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• v.2 no.2
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• pp.108-114
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• 2006

Objectives : Only a few prospective studies of panic disorder are available. This study investigated naturalistic outcome of panic disorder patients at twelve months after the initial diagnosis. Methods : A total of 84 subjects were diagnosed with panic disorder by diagnostic interview, Structured Clinical Interview for DSM-IV (SCID-IV) and Anxiety Disorder Interview Schedule for DSM-IV (ADISIV). Among them, 80 subjects could be evaluated by means of Panic Disorder Severity Scale (PDSS) at follow-up interview after twelve months. Treatment continuation was also examined at follow-up interview. Results : At initial intake, 80 patients were classified into 22% with mild, 33% with moderate-to-marked, and 45% with severe symptoms on the basis of their PDSS total score. At twelve months, 20% of patients reached remission, 65% had mild and 15% had moderate-to-marked symptoms. Initial panic symptom severity, presence of agoraphobia, panic symptom duration before diagnosis, number of comorbid Axis I disorders were associated with significantly higher PDSS total score at twelve months. Forty six percent of total patients continued medication and 23% have stopped treatment by clinician's recommendation and 31% have selfdiscontinued their medication. At twelve months, all three groups were improved but self-discontinuation group had significantly higher PDSS total score. Conclusion : In the one-year naturalistic outcome study of panic disorder patients, high percentage of patients achieved remission or had mild symptoms.

• Korean Journal of Clinical Pharmacy
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• v.34 no.1
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• pp.21-29
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• 2024

Background: Daytime sleepiness, a common phenomenon among adolescents focused on academics, has negative effects on aspects such as growth and overall learning. However, research on various drugs and diseases affecting daytime sleepiness is lacking in the reality. Therefore, this study aims to investigate the factors influencing daytime sleepiness in adolescents with daytime sleepiness. Methods: This study was conducted through a survey of 2,432 middle and high school students, aged 14 to 19. The questionnaire consisted of information on socio-demographic characteristics, overall health status, and sleep patterns. The Pediatric Daytime Sleepiness Scale (PDSS), translated into Korean, was used to assess daytime sleepiness. Daytime sleepiness was measured by calculating the total score for each item of the PDSS, and divided into two groups based on the cutoff value of 19, which was the upper quartile. Results: We analyzed a total of 1,770 students including 799 boys and 971 girls. Students with a PDSS score of 19 or higher made up 33.3% of boys and 66.7% of girls. In multivariate analyses, females, smoking, poor self-reported health level, sleep after 12 am, not feeling refreshed in the morning, headache, muscle pain, and scoliosis increased the risk of daytime sleepiness significantly. The AUROC of PDSS, including significant factors in multivariate analyses, was 0.751 (95% CI 0.725~0.776). Conclusions: Daytime sleepiness in adolescents affects growth, academic performance, and emotional stability. Therefore, it is important to manage medications, diseases, and other factors that affect daytime sleepiness on a social level.

• Journal of Oriental Neuropsychiatry
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• v.28 no.4
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• pp.333-340
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• 2017

Objectives: The purpose of this study was to evaluate the efficacy and safety of Korean medicine treatment for pregnant women with panic disorder. Methods: We treated pregnant women with panic disorder with Acupuncture, Herb extract granules, and Korean medicine psychotherapy. PDSS, BAI, and BDI were evaluated every two months. Results: PDSS was reduced from 24 points to 8 points. BAI was reduced from 35 points to 10 points. BDI was reduced from 22 points to 8 points. Mental and body symptoms were also reduced. Both mother and the baby were healthy after delivery. No specificities or adverse effects were reported during the entire treatment. Conclusions: Korean medicine treatment may be effective and safe to control symptoms of pregnant woman with panic disorder.

• Journal of Environmental Health Sciences
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• v.32 no.6
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• pp.539-542
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• 2006

The objective of this paper is to compare the applicability of assimilable organic carbon (AOC) or biodegradable dissolved organic carbon (BDOC) for quantifying biodegradable organic material (BOM) and bio-stability in distribution systems for a variety of finished waters. The study the data is derived from was part of an AWWARF and Tampa Bay Water tailored collaboration project to determine the effect of blending different waters on distribution system water quality. Seven different finished waters were produced from surface, ground, or brackish water on site and fed 18 independent pilot distribution systems (PDSs), either as single finished water or as a blend of several finished waters. AOC and BDOC have often been used as indicators of bacterial regrowth potential in distribution systems. In this study, AOC was the more useful assay of the two for the BOM concentrations observed in the PDSs. BDOC did not distinguish BOM while AOC did at the low BOM levels from many of the advanced treatments (e.g. RO, $O^3/BAC$). AOC in contrast allowed much more meaningful calculations of the consumption or production of AOC as the blends passed through the PDSs even for very low BOM blends. In addition, meaningful trends corresponding to changes in heterophic plate count (HPC) were observed for AOC but not for BDOC. Moreover, AOC stability was associated with waters produced from advanced membrane treatment.