• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.423-446
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• 2023

Shield TBM tunnel linings are segmented into segments and rings. This study investigates the response characteristics of the stress and displacement of the segment lining under seismic waves through modeling that considers the interface behavior between segments by applying a shell interface element to the contact surface between segments and rings. And there is no management criteria for ovaling deformation of segment linings in Korea. So, this study the ovality criteria and meaning of segment lining. The results of study showed that the distribution patterns of stress and displacement under seismic waves were similar between continuous linings and segment linings. However, the maximum values of stress and displacement showed differences from segment linings. The stress distribution of the continuous lining modeled as a shell type has a stress distribution that has continuity in the 3D cylindrical shape, but the segment lining is concentrated outside the segment, and the largest stress occurs at the location where the contact surface between the segment and the ring is concentrated. This intermittent and localized stress distribution shows an increasing as the ovality of the lining increases at seismic waves. The ovality at which the increase in stress distribution begins to show irregularity and localization is about 150‰. Ovality of 150‰ is an unrealistic value that cannot represent actual lining deformation. Therefore, the ovality of the segment lining increase with depth, but it does not have a significant impact on the stability caused by seismic load.

• Journal of Marine Life Science
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• v.9 no.1
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• pp.9-21
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• 2024

Paralytic shellfish poisoning (PSP) including Saxitoxin (STX) is caused by harmful algae, and poisoning occurs when the contaminated seafood is consumed. The mouse bioassay (MBA), a standard test method for detecting PSP, is being sanctioned in many countries due to its low detection limit and the animal concerns. An alternative to the MBA is the Neuro-2a cell-based assay. This study aimed to establish various test conditions for Neuro-2a assay, including cell density, culture conditions, and STX treatment conditions, to suit the domestic laboratory environment. As a result, the initial cell density was set to 40,000 cells/well and the incubation time to 24 hours. Additionally, the concentration of Ouabain and Veratridine (O/V) was set to 500/50 μM, at which most cells died. In this study, we identified eight concentrations of STX, ranging from 368 to 47,056 fg/μl, which produced an S-shaped dose-response curve when treated with O/V. Through inter-laboratory variability comparison of the Neuro-2a assay, we established five Quality Control Criteria to verify the appropriateness of the experiments and six Data Criteria (Top and Bottom OD, EC₅₀, EC₂₀, Hill slop, and R² of graph) to determine the reliability of the experimental data. The Neuro-2a assay conducted under the established conditions showed an EC₅₀ value of approximately 1,800~3,500 fg/μl. The intra- & inter-lab variability comparison results showed that the coefficients of variation (CVs) for the Quality Control and Data values ranged from 1.98% to 29.15%, confirming the reproducibility of the experiments. This study presented Quality Control Criteria and Data Criteria to assess the appropriateness of the experiments and confirmed the excellent repeatability and reproducibility of the Neuro-2a assay. To apply the Neuro-2a assay as an alternative method for detecting PSP in domestic seafood, it is essential to establish a toxin extraction method from seafood and toxin quantification methods, and perform correlation analysis with MBA and instrumental analysis methods.

• Journal of Korean Dental Hygiene Science
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• v.6 no.2
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• pp.79-89
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• 2023

Background and Objectives: The prevalence of dementia is steadily increasing each year, and preceding studies continue to explore the association between dementia and oral health. Dental hygienists require specialized competencies to provide appropriate dental healthcare services, necessitating the development of a tool for the objective measurement of their knowledge levels. This study aimed to develop a knowledge assessment tool for dental hygienists concerning considerations for dental care for patients with dementia. Methods: The study constructed preliminary items based on a literature review and then conducted expert validation, a pilot survey, and the main survey. The main survey was conducted among 220 dental hygienists. Validity and reliability analyses were conducted with the collected data to select the final items, and the correctness rates for each selected item were verified. Results: As a result of the analysis of the collected data, 18 items were eliminated out of a total of 40 preliminary items, leaving a total of 6 factors and 22 items. The Cronbach's α value for the selected items was 0.791. The six factors are as follows: 'Considerations during dental treatment for dementia patients' (5 items), 'medication side effects in dementia patients' (4 items), 'oral care methods for dementia patients' (4 items), 'communication with dementia patients' (4 items), 'psychological reactions of dementia patients' (3 items), and 'guidance for dementia patients' (2 items). The item with the highest correctness rate was item 2 of the 'guidance for dementia patients' category at 98.6%, while the item with the lowest correctness rate was item 2 of the 'psychological reactions of dementia patients' category at 5.9%. Conclusion: This study validated the reliability and validity of the knowledge assessment tool, which lays the foundation for future research on dental hygienists and dementia. It contributes essential data for ongoing education, development of educational programs, and establishing operational guidelines in healthcare institutions.

• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.257-265
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• 2024

In this study, we applied AEC(Auto Exposure Control), which is used in many chest examinations, to evaluate whether medical devices inserted into the body affect the dose and image quality of chest images. After attaching three HIMD(Human implantable medical devices) to the ion chamber, the Monte Carlo methodology-based program PCXMC(PC Program for X-ray Monte Carlo) 2.0 was applied to measure the effective dose by inputting the DAP(Dose Ares Product) value derived from the Pacemaker and CRT and Chemoport Additionally, to evaluate image quality, we set three regions of interest and one noise region on the chest and measured SNR and CNR. The final study results showed significant differences in DAP and Effective dose. There was a significant difference between Pacemaker and CRT when AEC was applied and not applied. (p<0.05) When applied, the dose increased by 37% for Pacemaekr and 52% for CRT. Chemoport showed a 10% increase in effective dose depending on whether AEC was applied, but there was no significant difference. (p>0.05) In the image quality evaluation, there was no significant difference in image quality between all HIMD insertions and AEC applied or not. (p>0.05) Therefore, when the HIMD was inserted into the chest during a chest x ray and overlapped with the ion chamber sensor, the effective dose increased, and there was no difference in image quality even at a low dose without AEC. Therefore, when performing a chest X-ray examination of a patient with a HIMD inserted, it is considered that performing the examination without applying AEC is a method that can be considered to reduce the patient's radiation exposure.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.1
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• pp.8-16
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• 2024

Limestone (CaCO₃, calcium carbonate), which is used as a raw material in the portland cement and steel industry, emits CO₂ through decarbonation by high temperatures in the manufacturing process. To reduce CO₂ emissions by the use of raw materials like limestone, it has been proposed to replace limestone with various industrial by-products that contain CaO but less or none of the carbonated minerals, that cause CO₂ emissions. Loss of Ignition (LOI), Thermogravimetric analysis (TG), and Infrared Spectroscopy (IR) are used to quantitative the amount of CO₂ emission by using these industrial by-products, but CO₂ emissions can be either over or underestimated depending on the characteristics of by-product materials. In this study, we estimated CO₂ contents by LOI, TG, IR and DTG(Differential Thermogravimetric analysis) of calcite(CaCO₃) and samples that contain CO₂ in the form of carbonate and whose weight increases by oxidation at high temperatures. The test results showed for CaCO₃ samples, all test methods have a sufficient level of reliability. On the other hand, for the CO₂ content of the sample whose weight increases at high temperature, LOI and TG did not properly estimate the CO₂ content of the sample, and IR tended to overestimate compared to the predicted value, but the estimated result by DTG was close to the predicted valu e. From these resu lts, in the case of samples that contain less than a few percent of CO₂ and whose weight increases during the temperature that carbonate minerals decompose, estimating the CO₂ content using DTG is a more reasonable way than LOI, TG, and IR.

• Journal of Service Research and Studies
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• v.14 no.1
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• pp.44-62
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• 2024

The development of online funeral services and social issues of eco-friendly funeral culture have raised awareness of the new need for online funeral culture. There have been several attempts to revitalize online funeral services in domestic institutions and companies, but the effect is weak. The purpose of this study is to propose a design that can improve the accessibility and usability of online memorial services by analyzing the usability problem factors through a First Time User Experience analysis of the online memorial platform. Therefore, in this study, in order to identify the problem factors of the online memorial platform, a literature review on the UX, OOBE, and FTUE theories was conducted. The subject of the study was the app 'Memorial'. Before analyzing the First-Time User-Experience, IA was compared and analyzed with other similar services to understand the characteristics of the UX service of the app 'Memorial', which is the subject of the study. In addition, tasks corresponding to the Unpack-Setup/Configure-First Use stage were performed on 10 subjects who had no experience using the online memorial platform. The experimental process was expressed as the UX Curve to identify factors that caused negative experiences. As a result, the major problem factors included unnecessary UI elements, the need for sensitive personal information at the membership stage, and lack of immersion in the service. The improvements included strengthening community functions to facilitate the sharing of emotions and promote smooth communication between users. We proposed UI/UX service developments that enhanced the app by incorporating these insights. In order to verify the effectiveness, serviceability, and value of the developed prototype, an interview with a expert was conducted. The interviewes consisted of three service design experts. This study was conducted to contribute to the quality improvement and activation of the recently emerging online funeral services. The study is significant as it aims to understand the current status of these services and identify the factors necessary to improve service accessibility and usability. Subsequent studies require in-depth user verification of how much the proposed improvement plan affects the actual user experience.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.107-117
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• 2024

This study investigated temporal changes in forest physical variables and their effects on thermal comfort and physiological and psychological responses. Environmental factors (air temperature, mean radiant temperature, wind speed, and relative humidity), the predicted mean vote (PMV), and the predicted percentage of dissatisfied (PPD) visitors were continuously measured between 9:00 AM and 6:00 PM. We assessed the physiological and psychological responses (heart rate variability, heart rate, oral temperature, blood pressure, pulse rate, thermal sensation vote, comfort sensation vote, and subjective feelings) of 30 male university students (average age: 21.7±1.9 years), who closed their eyes and relaxed for 5 minutes every hour. Examination of correlations between environmental factors and physiological responses showed that ① the mean radiant temperature, wind speed, and relative humidity significantly changed with time; ② PMV and PPD also showed significant changes over time, and the thermal sensation vote corresponded with PMV; however, the comfort sensation vote did not correspond with PPD; ③ Among the physiological responses, parasympathetic nerve activity, sympathetic nerve activity, heart rate, and diastolic blood pressure significantly varied with time, with parasympathetic nerve activity having the lowest value and sympathetic nerve activity the highest at the highest air temperature (2:00-4:00 PM); and ④ Air temperature, mean radiant temperature, and wind speed showed a negative correlation with parasympathetic nerve activity and a positive correlation with sympathetic nerve activity. These findings indicate that the relaxation effects of the forest environment depend on what time of day people are exposed to it, and the changes occurring in forest environmental factors over time modulate these effects.

• Sim-seong Yeon-gu
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• v.28 no.2
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• pp.107-138
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• 2013

The purpose of this article is to awaken our colleagues to the culture and mind issues that have been forgotten or neglected by contemporary psychiatry under the prevalence of materialistic orientation. Cultural psychiatry too, though it has been contributed a great deal to widen the mental vision of psychiatry, has revealed several limitations in its approach. In the course of one sided search for culture specific factors in relation to mental health, conventional cultural psychiatry has neglected an effort to explore the common root underlying the different cultures and the common foundation of human mind. Cross sectional comparisons of the cultures alone have inevitably prevented the global considerations to culutre and mind in historical aspects and the dynamic interactions between mind and culture more in depth. The author suggested that the total view of mind and total approach of analytical psychology of C.G. Jung might be capable to replenish those limitations. Author explained the ways of C.G. Jung's observations and experiences of non-western culture and his concepts of culture and mind. The author demonstrated Jung's view of culture with the example of Filial Piety, Hyo, the Confucian moral norm which can be regarded as components of the collective consciousness though connected with archetypal patterns of behavior of intimacy between parent and child. In regard to the coexistence of multi-religious cultures in Korea the author made a proposal of 'culture spectrum' model for understanding value orientations of person in religious cultures. He identified in case of the Korean 4 types of cultural spectrums: Person with predominantly the Buddhist culture; with the Confucian; with the Shamanist; and with the Christian culture. The author also made an attempt to depict the dynamic interactions of different religious cultures in historical perspectives of Korea. Concepts of mind from the Eastern thoughts were reviewed in comparison with Jung's view of mind. The Dao of Lao Zi, One Mind by Wonhyo, the Korean Zen master from the 7th century, the Diagram of the Heaven's Decree by Toegye, a renowned Neo-Confucianist of Korea from the 16th century and his theory of Li-Ki, were explored and came to conclusion that they represent certainly the symbol of the Self in term of C.G. Jung. The goal of healing is 'the becoming whole person'. Becoming whole person means bringing the person as an individual to live not only within the specific culture but also to live in the world beyond the culture which is deeply rooted in the primordial foundation of human mind.

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.1-44
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• 1969

The important results which have been obtained in the investigation can be recapitulated as follows. 1. As demostrated by the experimental results and analyses concerning their effects in the on-ground type mushroom house, the constructions in relation to the side wall and ceiling of the experimental houses showed a sufficient heat insulation on effect to protect insides of the houses from outside climatic conditions. 2. As the effect on the solar type experimental mushroom house which was constructed in a half basement has been shown by the experimental results and analyses, it has been proved to be effective for making use of solar heat. However there were found two problems to be improved for putting solar houses to practical use in the farm mushroom growing: (1) the construction of the roof and ceiling should be the same as for the on-ground type house, and (2) the solar heat generating system should be reconstructed properly. A trial solar heat generating system is shown in Fig. 40. 3. Among several ventilation systems which have been studied in the experiments, the underground earthen pipe and ceiling ventilation, and vertical side wall and ceiling ventilation systems have been proved to be most effective for natural ventilation. 4. The experimental results have shown that ventilation systems such as the vertical side wall and underground ventilation systems are suitable to put to practical use as natural ventilation systems for farm mushroom houses. These ventilation systems can remarkably improve the temperature of fresh air which is introduced into the house by heat transfers within the ventilation passages, so as to approach to the desired temperature of the house without any cooling or heating operation. For example, if it is assuming that x is the outside temperature and y is the amount of temperature adjustment made by the influence of the ventilation system, the relationships that exist between x and y can be expressed by the following regression lines. Underground iron pipe ventilation system ${\cdots}{\cdots}$ y=0.9x-12.8 Underground earthen pipe ventilation system ${\cdots}{\cdots}$y=0.96x-15.11 Vertical side wall ventilation system${\cdots}{\cdots}$ y=0.94x-17.57 5. The experimental results have shown that the relationships existing between the admitted and expelled air and the $Co_2$ concentration can be described with experimental regression lines or an exponent equation as follows: 1) If it is assumed that x is an air speed cm/sec. and y is an expelled air speed in cm/sec. in a natural ventilation system, since the y is a function of the x, the relationships that exist between x and y can be expressed by the regression lines shown below: 2) If it is assumed that x is an admitted volume of air in $m^3/hr$ and y is an expelled volume of air in $m^3/hr$ in a natural ventilation system, since the y is a function of the x, the relationships that exist between x and y can be expressed by the regression lines shown below. 3) If it is assumed that the expelled air speed in cm/sec and replacement air speed in cm/sec. at the bed surface in a natural ventilation system are shown as x and y, respectively, since the y is a function of the x, the relationships that exist between x and y can be expressed by the following regression line: G.E. (100%)- C.V. (50%) ventilation system${\cdots}$ y=0.54X+0.84 4) If it is assumed that the replacement air speed in cm/sec. at the bed surface is shown as x, and $CO_2$ concentration which is expressed by multiplying 1000 times the actual value of $CO_2$ % is shown as y, in a natural ventilation system, since the y is a function of the x the relationships that exist between x and y can be expressed by the following regression line: G.E. (100%)- C.V. (50%) ventilation system${\cdots}{\cdots}$ y=114.53-6.42x 5) If it is assumed that the expelled volume of air is shown as x and the $CO_2$ concentration which is expressed by multiplying 1000 times the actual of $CO_2$ % is shown as y in a natural ventilation system, since the y is a function of of the x, the relationships that exist between x and y can be expressed by the following exponent equation: G.E. (100%)-C.V. (50%) ventilation system${\cdots}{\cdots}$ $$y=127.18{\times}1.0093^{-X}$$ 6. The experimental results have shown that the ratios of the crass sectional area of the G.E. and C.V. vent to the total cubic capacity of the house, required for providing an adequate amount of air in a natural ventilation system, can be estimated as follows: G.E. (admitting vent of the underground ventilation)${\cdots}{\cdots}$ 0.30-0.5% (controllable) C.V. (expelling vent of the ceiling ventilation)${\cdots}{\cdots}$ 0.8-1.0% (controllable) 7. Among several heating devices which were studied in the experiments, the hot-water boilor which was modified to be fitted both as hot-water toiler and as a pressureless steam-water was found most suitable for farm mushroom growing.

• Journal of Korean Society of Forest Science
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• v.16 no.1
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• pp.1-32
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• 1972

By means of the interspecific hybridization in the Sub-genus Diploxylon of the Genus Pinus, $F_1$ hybrids of Pinus rigida${\times}$elliottii, Pinus rigida${\times}$radiata, P. rigida${\times}$serotina and P. densiflora${\times}$thunbergii had been produced. And on the basis of the crossabilities of these hybrids the taxonomic affinities of these pines were examined. And the needle characteristics of these hybrid and the occurence of phenolic substances in these $F_1$ hybrid were also investigated to see the potential usefulness of these characteristics for the diagnosis of the taxonomic affinity. And, the growth performances of the $F_1$ hybrids have also been compared with those of parental species. In order to contribute to the establishment of the hybrid seed orchard the introgression phenomena between P. densiflora and P. thunbergii in the eastern coastal area have also been investigated along with the investigation of the heterozygosity of plus trees of P. densiflora growing in the clone bank in Suwon. And the results were summarized as follows. 1. On the basis of crossabilities as well as on the taxonomic affinities according to the systems of Shaw, Pilger and Duffield, it has been proven that the parental species of those hybrids are of close affinities and range of the fertile hybrid seed production rate was as high as 28-58% in the best hybrid combination (Table 13). 2. Among those hybrids, the ${\times}$ Pinus, rigiserotina hybrid seemed to be most promising in the growth performance exhibiting 109-155% more volume growth compared to the seed parent with the statistic significance of 1% level (Tables 16 and 17). 3. Notwithstanding the fact that the all of the pollen parents are cold tender, all hybrids exhibit cold hardiness as much as their seed parent and it seems to suggest that the characteristics of cold hardiness were transmitted from the seed parent. 4. Though a striking difference in needle length was observed between the parental species of each hybrid, it was difficult to distinguish each hybrid from their seed parent by the needle length except ${\times}$P. rigiserotina which is characterized by long needle which is 65% more longer than the needle of the seed parent (Table 21). 5. With regard to the anatomical characteristics of needle, the hypoderm is apparently thicker in most of the $F_1$ hybrid pines and the characteristics of resin canals are dominated by medial in most $F_1$ hybrid. And, the fibrovascular bundles were apart as were in their seed parent. Therefore it was found to be possible to distinguish the hybrids pines from their parents by the needle characteristics. And, it is to be noticed that the ${\times}$P. densithunbergii was more close to the pollen parent having RDI value of 0.73 (Fig.l, Table 22). 6. It has been demonstrated that ${\times}$P. rigielliottii, ${\times}$P. rigiradiata and ${\times}$P. rigitaeda have a phenolic substance (No.7) of light yellow at Rf-0.46, same as their seed parent, but no trace of phenolic substance was observed in their pollen parent. This fact will serve as an important criteria for early identification of hybridity in progeny testing. However, the fact that both of ${\times}$P. rigiserotina and ${\times}$P. densithunbergii exhibit the same reactions of phenolic substances as well their parental species seems to indicate the close affinities between the parental species of the respective hybrid (Fig.2, Table 23). 7. The separation and the reaction of phenolic substance developed on TLC were found to be same in the same species showing no variations between the individuals, and no variations due to tree part of sampling, tree age or pollen sources. And the reaction was also observed regardless of the not varied by the kind of developing solvent whether it is Aceton-Chloroform (3:7 v/v) or Benzene-Methanol-Acetic acid (90:16:8 v/v). 8. The introgression phenomena of natural Pinus densifiora stand in both east and west coastal area indicates that the major part of the red pines investigated are all heterozygous and the heterozygosity of pines are higher in the west coast than in the east coast(Tables 24 and 25). 9. Based on the RDI, among the plus trees of Pinus densiflora selected in Korea and Japan as well, no pure P. densiflora has been found. Since all of the sample trees of Pinus densiflora were found to be as heterozygous bearing part of the characteristics of P. thunbergii, those red pines were considered to be natural heterotic hybrid pines(Figs. 3 and 4. Tables 26 and 27).