• Journal of the Korean Geotechnical Society
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• v.22 no.12
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• pp.67-76
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• 2006

The reasonable assessment of the shear stiffness of a dredged soft ground and soft clay is difficult due to the soil disturbance. This study addresses the development and application of a new in-situ shear wave measuring apparatus (field velocity probe: FVP), which overcomes several of the limitations of conventional methods. Design concerns of this new apparatus include the disturbance of soils, cross-talking between transducers, electromagnetic coupling between cables, self acoustic insulation, the constant travel distance of S-wave, the rotation of the transducer, directly transmitted wave through a frame from transducer to transducer, and protection of the transducer and the cable. These concerns are effectively eliminated by continuous improvements through performing field and laboratory tests. The shear wave velocity of the FVP is simply calculated, without any inversion process, by using the travel distance and the first arrival time. The developed FVP Is tested in soil up to 30m in depth. The experimental results show that the FVP can produce every detailed shear wave velocity profiles in sand and clay layers. In addition, the shear wave velocity at the tested site correlates well with the cone tip resistance. This study suggests that the FVP may be an effective technique for measuring the shear wave velocity in the field to assess dynamic soil properties in soft ground.

• Journal of the Korean Geotechnical Society
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• v.25 no.2
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• pp.45-54
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• 2009

The electrical characteristics of soils have been used for investigating soil properties. The purpose of this study is the development and application of the electrical resistivity cone probe (ERCP) for the evelation of the porosity in the field with high precision. The shape of the probe tip is a cone shape to minimize the disturbance during penetration. In addition, the four terminal pair configuration is adopted to minimize the electrical interference. The electrical resistances are continuously measured during penetration of the ERCP using penetration rigs with 0.33 mm/sec penetration rate at Incheon and Busan sites. With the measured resistance profile and electrical resisivity of electrolyte of undisturbed samples, soil porosity profiles are obtained by using Archie's law. The empirical coefficients for the Archie's law are obtained based on the electrolyte extracted from the undisturbed samples. The estimated porosity profiles show similar trends to those of in-situ penetration tests such as SPT, CPT, and DMT. This study suggests that the ERCP may be an effective tool for the porosity estimation in the field with minimum disturbance.

• 한국노년학
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• v.39 no.4
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• pp.825-846
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• 2019

This study aims to identify subgroups of ageism among young adults of age 20-39, and to examine its relationship to perceptions of generational conflict and elderly welfare policy. Latent Profile Analysis(LPA) was applied on the data 'Survey on Age Integration and Generational Integration', which was executed by institute for Age Integration Researchof Ewha Womans university, and descriptive statistics and cross-tabulation analysis were performed to examine the socio-demographic characteristics of each subgroup. Then, regression analysis was performed to observe the effect of the subgroups on the perceptions of generational conflict and elderly welfare policy. The results are as follows. The resulting subgroups of ageism among young adults were 'compound perception on aging and active age discrimination', 'medium-level aging anxiety and passive age discrimination', and 'low-level aging anxiety and beyond age discrimination'. Subgroups of ageism affected both perceptions of generational conflict and elderly welfare policy, whereas social support only affected perception of elderly welfare policy. Based on the results, political implications, such as activation of education on perception on aging, expansion of generational exchange for age integration, and renewal of social atmosphere for intergenerational coexistence, which will promote social integration

• Journal of Korean Biological Nursing Science
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• v.4 no.1
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• pp.25-39
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• 2002

The purpose of this study is to develop and evaluate a web-based instruction Program(WBI) to help nurses improving their knowledge and skill of cardiopulmonary resuscitation. Using the model of web-based instruction(WBI) program designed by Rhu(1999), this study was carried out during February-April 2002 in five different steps; analysis, design, data collection and reconstruction, programming and publishing, and evaluation. The results of the study were as follows; 1) The goal of this program was focused on improving accuracy of knowledge and skills of cardiopulmonary resuscitation. The program texts consists of the concepts and importances of cardiopulmonary resuscitation(CPR), basic life support(BLS), advanced cardiac life support(ACLS), treatment of CPR, nursing care after CPR treatment. And in the file making step, photographs, drawings and image files were collected and edited by web-editor(Namo), scanner and Adobe photoshop program. Then, the files were modified and posted on the web by file transfer protocol(FTP). Finally, the program was demonstrated and once again revised by the result, and then completed. 2) For the evaluation of the program, 36 nurses who in K university hospital located in D city, and related questionnaire were distributed to them as well. Higher scores were given by the nurses in its learning contents with $4.2{\pm}.67$, and in its structuring and interaction of the program with $4.0{\pm}.79$, and also in its satisfactory of the program with $4.2{\pm}.58$ respectively. In conclusion, if the contents of this WBI educational program upgrade further based upon analysis and applying of the results the program evaluation, it is considered as an effective tool to implement for continuing education as life-long educational system for nurse.

• Progress in Medical Physics
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• v.25 no.4
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• pp.271-280
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• 2014

Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.8
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• pp.367-376
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• 2007

In this paper, we introduce an application-specific and adaptive power management technique for portable systems that support dynamic voltage scaling (DVS). We exploit both the idle time of multitasking systems running soft real-time tasks as well as memory- or CPU-bound code regions. Detailed power and execution time profiles guide an adaptive power manager (APM) that is linked to the operating system. A post-pass optimizer marks candidate regions for DVS by inserting calls to the APM. At runtime, the APM monitors the CPU's performance counters to dynamically determine the affinity of the each marked region. for each region, the APM computes the optimal voltage and frequency setting in terms of energy consumption and switches the CPU to that setting during the execution of the region. Idle time is exploited by monitoring system idle time and switching to the energy-wise most economical setting without prolonging execution. We show that our method is most effective for periodic workloads such as video or audio decoding. We have implemented our method in a multitasking operating system (Microsoft Windows CE) running on an Intel XScale-processor. We achieved up to 9% of total system power savings over the standard power management policy that puts the CPU in a low Power mode during idle periods.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.191-197
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• 2018

This study investigated the influence of starch extraction (ST-EX) solutions on the extraction yield and characteristics of Chinese yam (CY) starches from domestic Dioscorea batatas. Ascorbic acid (VitC), $Na_2S_2O_3$, $NaHCO_3$, and $Na_2CO_3$ were used as ST-EX solutions (0.4%, w/v). The extracted CY starches were examined for ST-EX yield, chemical composition, size distribution, X-ray diffraction, solubility, swelling power, gelatinization, and pasting viscosity. The highest ST-EX yield was obtained from $NaHCO_3$, followed by VitC. Lower protein content, relative crystallinity, and gelatinization enthalpy were found in CY starches from alkaline ST-EX solutions ($NaHCO_3$ and $Na_2CO_3$). Size distribution and gelatinization temperature did not generally differ for CY starches from the different ST-EX solutions. Pasting viscosities increased in the order from $Na_2CO_3$ > $Na_2S_2O_3$ > $NaHCO_3$ > VitC ST-EX solutions. Thus, VitC may be most appropriate to extract CY starch from Dioscorea rhizomes, considering its ST-EX yield, total starch content, and variation in pasting viscosity.

• Journal of The Korean Association For Science Education
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• v.36 no.5
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• pp.757-768
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• 2016

This study developed an SSI (Socio-Scientific Issue) discussion program that applies a creative technique called six thinking hats, and then investigated the differences in argumentation patterns and effects on the decision-making abilities of each character feature of students between SNS debate and existing face to face debate. There were three SSI themes - Designer Babies, embryonic stem cell study, and legitimacy of abortion. Students were divided into two groups, the debate group using SNS and face to face debate group. The character patterns of students were divided to 'extraversion,' 'agreeableness,' and 'conscientiousness' through test sheets for character features for each student. Both groups were educated for creative discussion methods using six thinking hats and then, the class progressed. As a result of analyzing argumentation patterns used in SNS debate and face to face debate, the most used argumentation pattern was the "cause pattern." But comparing to face to face debate, other patterns (mark, inference, authority, motive) were also used in SNS debate. The study analyzed three factors of decision-making ability for each character feature of students such as complexity, perspectives, and inquiry. As a result, for 'complexity' factor, there was a significant difference between SNS debate group and face to face debate group only in the student group of Agreeableness. For 'perspectives' factor, there were significant differences between SNS debate group and face to face debate group in all three characters. Finally, for inquiry, there were no significant differences between SNS debate group and face to face debate group in all three characters. Accordingly it would be necessary to apply SNS debate using the six thinking hats in SSI education to enhance perspectives.

• Progress in Medical Physics
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• v.9 no.2
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• pp.77-88
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• 1998

Wedge shaped isodoses are desired in a number of clinical situations. Hard wedge filters have provided nominal angled isodoses with dosimetric consequences of beam hardening, increased peripheral dosing, nonidealized gradients at deep depths along with the practical consequendes of filter handling and placement problems. Dynamic wedging uses a combination of a moving collimator and changing monitor dose to achieve angled isodoses. The segmented treatment tables(STT) that monitor unit setting by every distance of moving collimator, was induced by numerical formular. The characteristics of dynamic wedge by STT compared with real dosimetry. Methods and Materials : The accelerator CLINAC 2100C/D at Yonsei Cancer Center has two photon energies (6MV and 10MV), currently with dynamic wedge angles of 15$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$ and 60$^{\circ}$. The segmented treatment tables(STT) that drive the collimator in concert with a changing monitor unit are unique for field sizes ranging from 4.0cm to 20.0cm in 0.5cm steps. Transmission wedge factors were measured for each STT with an standard ion chamber. Isodose profiles, isodose curves, percentage depth dose for dynamic wedge filters were measured with film dosimetry. Dynamic wedge angle by STT was well coincident with film dosimetry. Percent depth doses were found to be closer to open field but more shallow than hard wedge filter. The wedge transmission factor were decreased by increased the wedge angle and more higher than hard wedge filters. Dynamic wedging probided more consistent gradients across the field compared with hard wedge filters. Dynamic wedging has practical and dosimetric advantages over hard filters for rapid setup and keeping from table collisions. Dynamic wedge filters are positive replacement for hard filters and introduction of dynamic conformal radiotherapy and intensity modulation radiotherapy in a future.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.165-173
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• 2003

This study was carried out to develop a better fruit-dressing than previous mayonnaise in terms of calories, salt content and color, using kiwis, oranges, strawberries, and apples. This study was aimed to identify the perception, physico-chemical and sensory characteristics of the 4-kinds of fruits dressing. The results were as follows: The perception of the fruit dressings received the highest score (3.90) for 'It's convenience foods'. The misture in the dressings ranged from 49.3 to 59.4%, and was highest in apple dressing, followed by the kiwi, strawberry, and orange dressings, in that order. The crude ash for the dressings ranged from 0.8 to 1.4%, and was highest in the orange dressing. The L value was highest in the apple dressing, the a(-) value in the kiwi dressing, the a(＋) value in the strawberry dressing and the b value in the orange dressing. The Ca/ P ratio was about 1.17 : 1. The results of mineral contents analyses were also examined. The calcium, magnesium and potassium levels were highest in the orange dressing. The mineral contents of fruit dressings were 6.7 to 20.4mg/100g for calcium, 6.5 to 20.5mg/100g for magnesium and 67.2 to 182.6mg/100g for potassium. The sodium content of the fruit dressings were lower than in the previous mayonnaise, especially for the kiwi-dressing, which was 30% that in the mayonnaise. As a result of the sensory evaluations of the 4-kinds of fruits dressing, the kiwi dressing received the highest scores (3.50) of all the fruit-dressings in relation to the taste and palatability. Fruit are good for producing dressings that are low in calories and salt, with kiwi dressing proving to be the best of those fruits tested.