• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.1
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• pp.109-116
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• 2024

The Rapid Hardening Composite Mat (RHCM) is a product that improves the initial strength development speed of conventional Geosynthetic Cementitious Composite Mats (GCCM). It offers the advantage of quickly securing sufficient strength in railway slopes with insufficient formation level, and provides benefits such as preventing slope erosion and inhibiting vegetation growth. In this study, an analysis of the practical applicability of RHCM in railway settings was conducted through experimentation. The on-site applicability was assessed by categorizing it into fire resistance, durability, and stability, and conducting combustibility test, ground contact pressure test, and daily displacement analyses. In the case of South Korea, where a significant portion of the territory is composed of forested areas, the prevention of slope fires is imperative. To analyze the fire resistance of RHCM, combustibility tests were conducted as an essential measure. Durability was assessed through ground contact pressure tests to analyze the deformation and potential damage of RHCM caused by the inevitable use of small to medium-sized equipment on the construction surface. Furthermore, daily displacement analysis was conducted to evaluate the structural stability by comparing and analyzing the displacement and behavior occurring during the application of RHCM with railway slope maintenance criteria. As a result of the experiments, the RHCM was analyzed to meet the criteria for heat release rate and gas toxicity. Furthermore, the ground contact pressure was observed to be consistently above 50 kPa during the curing period of 4 to 24 hours under all conditions. Additionally, the daily displacement analyzed through field site experiments ranged from -1.7 mm to 1.01 mm, confirming compliance with the criteria.

• Journal of Korean Elementary Science Education
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• v.43 no.3
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• pp.402-414
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• 2024

The purpose of this study is to explore the experiences of Science Chief Teachers in schools, focusing on the specific activities in which they engage during the school year as a part of the science curriculum in the school. To do so, five research participants were selected who were in charge of the activities of the Science Chief Teacher in elementary schools. After the interviews, their activities and roles were categorized into "planning and implementation" and "management and supplementation." In addition, the research participants were asked to bring documents they had drafted and provide information about accomplishments related to science contests, lists of materials and equipment used in science labs, and other materials to be used as reference data for the research. As prompted by the research, the category of "planning and implementation," which represented the activities conducted by the Science Chief Teachers, was further classified into "operation of the intramural events for the Month of Science at the beginning of the school year," "participation in contests sponsored by the Office of Education in accordance with the results of the intramural events," " the operation of the science club in school," and "preparation for the end of the year evaluation of the science education performance." As for the category of "management and supplementation," it was further classified into "constant management and improvement of the science lab," "maintenance of the relationship with the public service officials present at science lab," and "management of other matters related to the science education." Through this study, it was possible to look into the activities of the Science Chief Teachers who supported the smooth progress of science education in schools. This study will provide implications for improving the work efficiency of the Chief Science Teachers and indicate the difficulties expected in the future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.3
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• pp.203-212
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• 2005

Cellulose insulation is primarily manufactured from recycled newsprint and treated with fire retardants for the fire resistance. Thanks to the fire retardants, it is not combustible and flammable. In addition to that, Its thermal resistance is much better than that of fiberglass or rock wool. It is made from waste paper and easily decayed when it is demolished, and it has small embodied energy. So it is very environment-friendly building material. For broader use of cellulose insulation in buildings in Korea, it is necessary to test its physical performance to compare the results with the requirements on the Korean Building Code. To this end, apparent thermal conductivity (ka) measurements of Korean-made loose-fill cellulose insulations were recently completed using equipment that was built and operated in accordance with ASTM C 518 and the fire resistance was tested in accordance with ASTM C 1485. Korean loose-fill cellulose has thermal conductivity about 5% greater than the corresponding U.S. product at the same density. This is likely due to differences in the recycled material being used. Both spray-applied and loose-fill cellulose insulation lose about 1.5% of their thermal resistivity for $5.5^{\circ}C$ increase in temperature. The fire resistance of cellulose insulation is increased in linear proportion to the increase of the rate of fire retardant. Thanks to the high fire resistance, cellulose insulation can be used as a substitution of Styrofoam or Urethane foam which is combustible. The thermal conductivity of cellulose insulation was $0.037-0.043W/m{\cdot}K$ at the mean specimen temperature from $4-43^{\circ}C$. It corresponds to the thermal resistance of "Na Grade" according to the Korean Building Code. The effect of chemical content on thermal conductivity was negligible for all but the chemical-free specimen which had the highest value for the thermal conductivity over the temperature range tested. The thermal resistance of cellulose insulation is better than that of fiberglass or rock wool, and its fire resistance is higher than that of Styrofoam or Urethane foam. Therefore it can be substituted for those above considering its physical performance. Cellulose insulation is no more expensive than Styrofoam or rock wool, so it is recommended to use it more widely in Korea.

• Journal of Intelligence and Information Systems
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• v.16 no.2
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• pp.73-94
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• 2010

The attending system is a medical system that allows doctors in clinics to use the extra equipment in hospitals-beds, laboratory, operating room, etc-for their patient's care under a contract between the doctors and hospitals. Therefore, the system is very beneficial in terms of the efficiency of the usage of medical resources. However, it is necessary to develop a strong support system to strengthen its weaknesses and supplement its merits. If doctors use hospital beds under the attending system of hospitals, they would be able to check a patient's condition often and provide them with nursing care services. However, the current attending system lacks delivery and assistance support. Thus, for the successful performance of the attending system, a networking system should be developed to facilitate communication between the doctors and nurses. In particular, the nursing records in the attending system could help doctors monitor the patient's condition and provision of nursing care services. A nursing record is the formal documentation associated with nursing care. It is merely a data repository that helps nurses to track their activities; nursing records thus represent a resource of primary information that can be reused. In order to maximize their usefulness, nursing records have been introduced as part of computerized patient records. However, nursing records are internal data that are not disclosed by hospitals. Moreover, the lack of standardization of the record list makes it difficult to share nursing records. Under the attending system, nurses would want to minimize the amount of effort they have to put in for the maintenance of additional records. Hence, they would try to maintain the current level of nursing records in the form of record lists and record attributes, while doctors would require more detailed and real-time information about their patients in order to monitor their condition. Therefore, this study developed a system for assisting in the maintenance and sharing of the nursing records under the attending system. In contrast to previous research on the functionality of computer-based nursing records, we have emphasized the practical usefulness of nursing records from the viewpoint of the actual implementation of the attending system. We suggested that nurses could design a nursing record dictionary for their convenience, and that doctors and nurses could confirm the definitions that they looked up in the dictionary through negotiations with intelligent agents. Such an agent-based system could facilitate networking among medical institutes. Multi-agent systems are a widely accepted paradigm for the distribution and sharing of computation workloads in the scientific community. Agent-based systems have been developed with differences in functional cooperation, coordination, and negotiation. To increase such communication, a framework for a multi-agent based system is proposed in this study. The agent-based approach is useful for developing a system that promotes trade-offs between transactions involving multiple attributes. A brief summary of our contributions follows. First, we propose an efficient and accurate utility representation and acquisition mechanism based on a preference scale while minimizing user interactions with the agent. Trade-offs between various transaction attributes can also be easily computed. Second, by providing a multi-attribute negotiation framework based on the attribute utility evaluation mechanism, we allow both the doctors in charge and nurses to negotiate over various transaction attributes in the nursing record lists that are defined by the latter. Third, we have designed the architecture of the nursing record management server and a system of agents that provides support to the doctors and nurses with regard to the framework and mechanisms proposed above. A formal protocol has also been developed to create and control the communication required for negotiations. We verified the realization of the system by developing a web-based prototype. The system was implemented using ASP and IIS5.1.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.19-30
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• 2012

Due to the fact that the social environment is improved and the urban development is stabilized, the demand of new construction of apartment becomes slowdown. Accordingly, there are many researches to lengthen the service life of the existing apartment through the remodeling and its importance is continuously rising. However, reliable design specifications and guidelines for the design of remodeling with partial demolition are not provided yet in Korea. Specially, in the apartment remodeling, slab collapse accidents take major portion in all accidents that reported by Korean Government. It is very important to prevent intial crack of slab because intial crack could cause severe accident like collapse of all structure in a short period of time. The purpose of this study is to develop structural guidelines that could guarantee the structural safety and serviceability of slab structure and could be adopted in Korean remodeling with partial demolition. There are mainly two components to determine structural behavior of slab structure. One is the shape of slab structure and the other is load which is resisted by the slab structure. In this study, the weight per unit volume of concrete debris and concrete strength are estimated through the analysis of previous researches to recognize the relationship between the shape of slab and load that loaded on the slab. Accordingly, approximately 300 pieces of floor plan are collected and analyzed. The finite element analysis is conducted using these analyzed and estimated results. From the finite element analysis results, the limited stacking height of debris is suggested and the stacking method is also discussed. In addition, to find the relationship between movement of demolition equipment and structural behavior of slab, the static and dynamic loading tests are conducted. From the results of loading tests, the impact factor which will be considered in the remodeling design could be estimated.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.140-146
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• 2019

In order to manage non-point sources, the paradigm of the system should be changed so that the management of non-point sources will be systematized from the beginning of the use and development of the land. It is necessary to change the method of national subsidy support and poeration plan for the non-point source management area. In order to increase the effectiveness of the non-point source reduction project, it is necessary to provide a minimum support ratio and to provide additional support according to the performance of the local government. A new system should be established to evaluate the performance of non-point source reduction projects and to monitor the operational effectiveness. It is necessary to establish the related rules that can lead the local government to take responsible administration so that the local governments faithfully carry out the non-point source reduction project and achieve the planned achievement and become the sustainable maintenance. Alternative solutions are needed, such as problems with the use of $100{\mu}m$ filter in automatic sampling and analysis, timely acquisition of water sampling and analysis during rainfall, and effective management of non-point sources network operation management. As an alternative, it is necessary to consider improving the performance of sampling and analysis equipment, and operate the base station. In addition, countermeasures are needed if the amount of pollutant reduction according to the non-point source reduction facility promoted by the national subsidy is required to be used as the development load of the TMDLs. As an alternative, it is possible to consider supporting incentive type of part of the maintenance cost of the non-point source reduction facility depending on the amount of pollutants reduction.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.4
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• pp.20-36
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• 2022

This study aims to provide basic data for high-quality street tree management by setting reasonable management items and appropriate unit prices by reviewing the adequacy of current street tree management. Currently, street tree management items, except for street tree pruning, use general landscape tree quantity per unit for the street tree management quantity per unit. KEPCO (Korea Electric Power Corporation) applied pruning items from standard electric production infrastructure and carried out the activities at an average unit price of 51% lower for heavy pruning and 39% lower for light pruning than the standard estimate. This was judged to be a level that could not maintain or increase the quality of street tree management. It was determined that an appropriate standard unit price for street tree management was necessary. To improve the quantity per unit for the proper management of street trees, it was necessary to review costs in the field. However, due to the absence of data on actual construction costs in the domestic landscape field, detailed items of the US RSMeans Building Construction Cost Data (RSMeans) were reviewed, and the actual construction costs were calculated by applying personal domestic expenses. As a result, the standard of the estimated unit showed a good ratio of 107% for heavy pruning of street tree pruning compared to the actual construction cost, but light pruning was underestimated with a 59% ratio. Shrub pruning was 82%, weeding was 92%, tree fertilization was 87%, and windbreak wall installation was 91% under-engineered. In addition, it was also confirmed that the watering by sprinkler trucks and chemical spraying were over-designed compared to the actual construction cost at the rates of 118% and 124%, respectively. Due to the specificity of the street trees, the increase in personal expenses and the input cost of equipment, such as road safety controls, were judged to be the main cause of the underestimation of items. Therefore, it is necessary to add items related to street trees and general landscape trees to the landscape maintenance items of the standard of the estimated unit.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.2
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• pp.17-24
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• 2023

A post-processing technique for the measurement signal of a solenoid-type sensor is introduced. The solenoid-type sensor nondestructively evaluates an external tendon of prestressed concrete using the total flux leakage (TFL) method. The TFL solenoid sensor consists of primary and secondary coils. AC electricity, with the shape of a sinusoidal function, is input in the primary coil. The signal proportional to the differential of the input is induced in the secondary coil. Because the amplitude of the induced signal is proportional to the cross-sectional area of the tendon, sectional loss of the tendon caused by ruptures or corrosion can be identified by the induced signal. Therefore, it is important to extract amplitude information from the measurement signal of the TFL sensor. Previously, the amplitude was extracted using local maxima, which is the simplest way to obtain amplitude information. However, because the sampling rate is dramatically decreased by amplitude extraction using the local maxima, the previous method places many restrictions on the direction of TFL sensor development, such as applying additional signal processing and/or artificial intelligence. Meanwhile, the proposed method uses amplitude demodulation to obtain the signal amplitude from the TFL sensor, and the sampling rate of the amplitude information is same to the raw TFL sensor data. The proposed method using amplitude demodulation provides ample freedom for development by eliminating restrictions on the first coil input frequency of the TFL sensor and the speed of applying the sensor to external tension. It also maintains a high measurement sampling rate, providing advantages for utilizing additional signal processing or artificial intelligence. The proposed method was validated through experiments, and the advantages were verified through comparison with the previous method. For example, in this study the amplitudes extracted by amplitude demodulation provided a sampling rate 100 times greater than those of the previous method. There may be differences depending on the given situation and specific equipment settings; however, in most cases, extracting amplitude information using amplitude demodulation yields more satisfactory results than previous methods.

• Geophysics and Geophysical Exploration
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• v.26 no.2
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• pp.52-61
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• 2023

The use of ultra-high-resolution (UHR) seismic surveys to preceisly characterize coastal and shallow structures have increased recently. UHR surveys derive a spatial resolution of 3.125 m using a high-frequency source (80 Hz to 1 kHz). A digital streamer system is an essential module for acquiring high-quality UHR seismic data. Localization studies have focused on reducing purchase costs and decreasing maintenance periods. Basic performance verification and application tests of the developed streamer have been successfully carried out; however, a comparative analysis with the existing benchmark model was not conducted. In this study, we characterized data obtained by using a developed streamer and a benchmark model simultaneously. Tamhae 2 and auxiliary equipment of the Korea Institute of Geoscience and Mineral Resources were used to acquire 2D seismic data, which were analyzed from different perspectives. The data obtained using the developed streamer differed in sensitivity from that obtained using benchmark model by frequency band.However, both type of data had a very high level of similarity in the range corresponding to the central frequency band of the seismic source. However, in the low frequency band below 60 Hz, data obtained using the developed streamer showed a lower signal-to-noise ratio than that obtained using the benchmark model.This lower ratio can hinder the quality in data acquisition using low-frequency sound sources such as cluster air guns. Three causes for this difference were, and streamers developed in future will attempt to reflect on these improvements.

• Journal of Korean Academy of Nursing
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• v.1 no.1
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• pp.27-43
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• 1970

This study is designed to find out proper nursing activities for the needs of the colostomy patients, i.e., mental and psychological as well as physical needs for rapid recovery, and to help them build up the follow-up care for proper social adjustment. The study is based on 268 cases out of 381 colostomy patient's records kept in Ewha Womans University Hospital, Yonsei Medical Center, and National Medical Center in between the period from Jan. 1953 to Jan. 1970. The items of study are mainly on etiology, sex, age, duration of hospitalization, mortality rate, seasonal frequency, time from the onset of illness to the admission of the hospital, signs and symptoms. 1. Frequency of onset by etiology: Neoplastic disease 112 cases (42%), Inflammatory disease 33 cases (12%), Congenital malformation 30 cases (11%), Intussusception 25 cases (9.3%), Trauma 24 cases (9%), Volvulus 17 cases (6.3%), and Crohn's disease 6 cases (2.2%). 2. By sex: male 167 cases (62.9%), and female 101 cases (37.1%). So the ratio of portion of male and female 2:1. 3. By age: under 1·year·old 27 cases (10.1%) highest, 41-50 yrs 54 cases (20.2%), 51-60 yrs 42 cases (15.5%), above 71 yrs 5 cases (1.9%). 4. Duration of hospitalization: the shortest is 2-days and the longest is 470 days. 1-20-days 52%, 40-60 days 14%. 5. Mortality rate: Under the 10-days-admission 19.5%, and the beyond 30-days-admission 3.9%. 6. Seasonal frequency: Higher in summer (32% ). 7. Signs and symptoms: abdominal pain (56%), abdominal distention (54%), vomiting (40%), bloody mucoid diarrhea (38%) , pain of anal region (18%), abdominal tenderness, anorexia, indigestion, constipation, disuria, tenesmus, high fever and chilling sensation, bile tingled vomiting. Nursing activities for the patient's physical needs are as follows: Skin care for colostomy region, Prevention of colostomy constriction and depression, Removal of an offensive odor, The use of colostomy bag-selection for, and demonstration of the use of inexpensive colostomy irrigation equipment, Personal hygiene, general skin care, care of hair, finger nails and toe-nails, Oral hygiene, sleep and rest, aquate, Daily activities, etc. Measures for regulation of bowl movement. Keeping the instruction of taking food, Preparing the meal and help for anorexia, Constipation and it's solution, Prevention of diarrhea, helping the removal of mucous, and stretch constricted steam as needed. Nursing activities for pt's socio-psychological needs are as follows; Help the patient to make decision for the operation, Remove pt's anxiety toward operation and anesthesia, To meet the pt's spiritual needs at his death bed, Help to establish family and friends cooperation, Help to reduce anxiety at the time of admission and it's solution, Help to meet religious need, Help to remove pt's anxiety for loosing his job and family maintenance, Follow-up studies for 7 cases have been done to implement the present thesis. The items of the personal interviews with the patients are as follows: Acceptability for artificial anus, The most anxious thing they had in mind at the time of discharge, The most anxious thing they hat·e in mind at present, Their friends and family's attitudes toward the patient after operation, Relations with other colostomy patients, Emotional damage from the operation, Physical problem of enema, irrigation, Control of diet, Skin care, Control of offensive odor, Patient's suggestions to nurses during hospital stay and after discharge. In conclusion, the follow-up care for colostomy patients shares equal weight or perhaps more than the post-operative care. The follow-up care should include the spiritual care for moral support of the patient, to drag him out of isolation and estrangement, and make him fully participate in social activities. It is suggested that the following measures would help to rehabilitate the colostomy patients (1) mutual acquaintance with other colostomy patients if possible form a sort of club for the colostomy patient to exchange their experiences in care (2) through the team work of doctor, nurse and rehabilitation specialists, to have a sort of concerted effort for betterment of the patient.