• Explosives and Blasting
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• v.42 no.1
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• pp.23-33
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• 2024

Recently, various techniques and patented methods on blasting operation are being newly developed. In this study, test construction of the MDS blasting method was performed, and the fragmentation size and the occurrence rate of rocks exceeding 300mm were measured and analyzed in comparing to normal blasting method. Test construction was performed three times each for normal and the MDS at the same bench for each round, and fragmentation size(P80) and occurrence rate of rocks exceeding 300mm(S30) were measured using digital image processing. A sieve bucket was also manufactured on-site to sort oversized rock particles from muck piles, and their weights and equivalents were measured to calculate actual values. As a result, the fragmentation size decreased of 21.0% with the MDS compared to normal, and 100-S30 decreased of 10.1%, with actual values decreasing of 7.6%. Although there were variations in blasting effects for each round due to differences in rock quality at site, overall, the MDS proved to be more effective compared to normal blasting method under equivalent conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.187-194
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• 1986

Present stadies were carried out to obtain fundermental data for effective management of the soils by investigating the physicochemical characteristics rubber fiber, humification grade and bearing power of peats and muck which were included in Geongdeog series, and Gimje series in Honam area. The results abtained were as follows; 1. Humification grade of peats were about 23, while that of muck soils was about 45-71 and those were higher in Gimje series than Bongnam series. 2. The organic tiers which humification grade was higher were high pH, bulk density, and contents of K, $P_2O_5$, B.S and while were low OM, T-C, T-N, Na, $SiO_2$ and rubbed fiber. 3. In peats and mucks, bulk density, pH, contents of T-N $P_2O_5$ and ash were negatively correlated with rubbed fiber and OM, CEC, T-C, PAC, C/N, C/P were positively correlated with one, while these physicochemical characteristics were oppositely correlated with humification grade. 4. Cone bearing power of each soil tiers was low in every Geongdeog series which had the thick organic tiers and showed poorly drainage and it was the highest in Gimje series which was similar to in organic soils because of its thin organic tiers.

• Korean journal of communication and information
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• v.41
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• pp.108-144
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• 2008

This study examines how the watchdog concert in journalism field has been created and develope4 Related studies found that the watchdog is related not so muck with free press theory as with a privilege awarded to the press because the press serves for the public interests. It was found that in the U.S., the watchdog concept was derived from the a lot of libel cases in the late 1890s. At the time, the newspaper owners and editors continuously claimed the very protection over vulnerability of newspaper's collecting, reporting, and printing news. While, in Korea, the concept of watchdog emerged in the late 1990s after the establishment of the Constitution Court. Even though the watchdog concert was accepted very late by the Korean courts, it is believed to be a kind of special privilege to prevent the press from being recklessly regulated in libel cases. Rather, the Korean courts expand the extent of the role of the press as a watchdog by deciding that not only the public officials and politicians but also other socially influential public figures could be included in the criticism from the press. However, how these court decisions can be practically implemented depends upon how the court apply the probability of the press to believe the news true and intention of malice in writing and publishing the stories.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.6
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• pp.599-614
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• 2014

When tunnelling with TBM (Tunnel Boring Machine), accessibility to tunnel face is very limited because tunnel face is mostly occupied by a bunch of machines. Existing techniques that can predict ground condition ahead of TBM tunnel are extremely limited. In this study, the TBM Resistivity Prediction (TRP) system has been developed for predicting anomalous zone ahead of tunnel face utilizing electrical resistivity. The applicability and prediction accuracy of the developed system has been verified by performing field tests at subway tunnel construction site in which an EPB (Earth Pressure Balanced) shield TBM was used for tunnelling work. The TRP system is able to predicts the location, thickness and electrical properties of anomalous zone by performing inverse analysis using measured resistivity of the ground. To make field tests possible, an apparatus was devised to attach electrode to tunnel face through the chamber. The electrode can be advanced from the chamber to the tunnel face to fully touch the ground in front of the tunnel face. In the 1st field test, none of the anomalous zone was predicted, because the rock around the tunnel face has the same resistivity and permittivity with the rock ahead of tunnel face. In the 2nd field test, 5 m thick anomalous zone was predicted with lower permittivity than that of the rock around the tunnel face. The test results match well with the ground condition predicted, respectively, from geophysical exploration, or directly obtained either from drilling boreholes or from daily observed muck condition.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.3-11
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• 1999

The effects of major cations in soils, soil : extractant ratio, and EDTA : lead stoichiometric ratio on the extraction efficiency of lead using EDTA were studied for 4 different actual lead-contaminated soils and one artificially lead-contaminated soil. Extraction of lead from the lead-contaminated soil was not affected by a soil : extractant ratio as low as 1 : 3 but instead was dependent on the quantity of EDTA present. Results of the experiments showed that the extraction efficiency for each soil was different, but if sufficiently large amount of EDTA was applied, all the lead may be extracted except for a soil from lead mining area. The differences in extraction efficiencies nay be due to the major cations present in soils which may compete with lead for active sites on EDTA. The total molar amount of major cations extracted was as muck as 20 times more than the added molar amount of EDTA. For some of the soils tested, the extraction efficiency of lead may be affected by being occluded in the Fe and Mn oxides present in the soil. While major cations present in the soil may be one of the factors affecting lead extraction efficiency, the type of lead species present may also play a role. When these factors affect severely, the using of EDTA to extract lead from lead-contaminated soil might be non-effective method.

• Journal of the Society of Disaster Information
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• v.8 no.3
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• pp.223-233
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• 2012

Steel fiber is high stiffness and large weight. So, Pumping hose to rupture of the safety management is difficult. Steel fiber caused by corrosion of the deterioration of durability and high-rebound losses are needed for the improvements. Thus, the revised regulations in 2009 by a steel fiber to reinforce other materials is possible. Variety of fiber reinforcement material for concrete review of applicability is needed. Steel fiber strength than the other fibers is large and by the geometry of the fibers are attached to improve performance. However, compared to steel fiber organic fibers and low modulus of elasticity and tensile strength of fiber and agglomeration occurs in the concrete to be used as reinforcement material is difficult. In this regard, the present study as a single object in the micro-fiber bouquet sharp entanglement through make muck attach surface area, distributed fibers from surfactant of the surface enhanced polyamide fibers, steel fiber and PP fiber reinforced concrete by comparing the scene to provide a basis for the use.

• Science of Emotion and Sensibility
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• v.8 no.3
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• pp.177-187
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• 2005

This article examined how the amount of information presented in ad design affect consumer's evaluation on the ad Existing researches have mainly considered external information presented in the ad from the resource principle perspective. This study investigated how internal information processing such as imagery information processing caused by brand names moderates persuasion effects according to the amount of external information through two experiments. The experiments leave us the conclusion that brand names presented in the ads stimulate imagery information processing when surplus cognitive resources do exist and they lead ad recipients' evaluation to positive direction in prestige brand condition and to the contrary to negative direction in non-prestige brand condition. The results contribute to the direction of ad design in that ad needs not contain as muck product-related information as needed in order to increase persuasion effects in prestige brand condition. Rather, it's necessary to leave the room for internal information processing such as imagery information processing by well structured brand equity. On the contrary, non-prestige brand needs to contain explicit product-relevant information to exert a potent influence on a4 persuasion. We hope this study result is helpful for design direction of advertisement in order to heighten persuasion effects toward ad recipients.

• Informatization Policy
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• v.25 no.3
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• pp.3-28
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• 2018

The purpose of this study is to analyze the research trends and present future research directions in the field of Cyber Physical System (CPS), a key element in the 4th Industrial Revolution, Industry 4.0, and Smart Manufacturing that are currently promoted as important innovation agenda both at home and abroad. In this study, (1) the concepts of industry 4.0, smart manufacturing and CPS are summarized; (2) analysis criteria of these fields are established; and 3) analysis results are presented and future research direction is proposed. 74 overseas and 8 domestic literature on manufacturing CPS from 2013 to 2017 are identified through 'Google Scholar Search'. Major results of the analysis are summarized as follows: (1) research on a common methodology and framework for the manufacturing CPS needs to be done based on the analysis of the existing methodologies and frameworks of various perspectives; (2) in order to improve the maturity of the manufacturing CPS, it is necessary to study actual deployment and operations of CPS, including the existing systems; (3) it is necessary to study the diagnostic methodology that can evaluate manufacturing CPS and suggest improvement strategy; and (4) as for the detailed model and tool, it is necessary to reinforce research on SCM production planning and human-machine collaboration while considering the characteristics of CPS.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.1029-1044
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• 2017

The Discrete Element Method (DEM) is one of the useful numerical methods to analyze the behavior of the ground formation by computing the motion and interaction using particles. The DEM has not been applied in civil engineering but also a wide range of industrial fields, such as chemical engineering, pharmacy, material science, food engineering, etc. In this study, to review a performance of the spoke-type earth pressure balance (EPB) shield TBM (Tunnel Boring Machine), the commercial software based on the DEM technology was used. An analysis of the TBM during excavation was conducted according to two pre-defined excavation conditions with the different rotation speed of a cutterhead. During the analysis, the resistant torque at the face of the cutterhead, the compressive force at the cutterhead and shield surface, the muck discharge at the screw auger were measured and compared. Upon the two kinds of excavation conditions, the applicability of the DEM analysis was reviewed as a modelling method for the TBM.

• Journal of Korean Academy of Nursing
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• v.13 no.3
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• pp.1-33
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• 1983

The role and function of nursing care nowadays, tend to acquire sophisicated technology because specialization has expended due to increase of the medical population and the improvement of national health standards. To implement nursing care independently as a professional nurse, the apprehension of specific knowledge and skill should be acquired during basic nursing education. So it is important for nursing education not only to include theory and actual techniques, but also to strengthen the practical training in the actual clinical setting. This study was carried out with the following objectives; 1. To survey the detailed content and frequency of actual nursing students display during their clinical training. 2. To investigate the detailed content and frequency of actual nursing behavior which students display in each clinical a area. 3. To identify the motive for selection of nursing as their major and to determine the degree of self confidence, extent of knowledge and recognition of nursing responsibility. 4. To observe the relationship between actual nursing behavior and each of the following; 1) Motive for selecting nursing as a major 2) Self confidence 3) Knowledge of nursing care 4) Recognition of nursing responsibility The conclusions of this study were as follows; 1. Among the detailed nursing behavior which junior nursing college students carry out in clinical training; taking respiration's showed the highest frequency, and taking body temperatures, blood pressures, and pulses and making beds were next in frequency in this order. 2. In detailed nursing behaviors according to clinical area; taking vital signs showed the highest frequency in the emergency room, pediatric ward, orthopedic ward, general surgical ward and internal medicine ward. However, in the operating room, assisting with endotracheal tube insertion and sterile techniques were showen to have the highest frequencies. In nursery, umbilical cord care and the measurement of body weight were the highest in frequency In neurosurgical ward, the measurement of vital signs, changing position and tracheostomy care were the highest in frequency. In obstetric and gynecological ward and in the delivery room, checking duration, intensity and frequency of contractions was the highest in frequency. 3. In regard to the motive for majoring in nursing, the aptitude and interest of the student had the highest percentage(32.86%), and self-confidence in nursing activities (M=3.36), knowledge in nursing activities.(M=3. 09), and the recognition of the nursing activity (M= 3.76) wire in the middle range. 4. When the detailed nursing behaviors were compared with motive, self confidence, knowledge and recognition, it was found that when the nursing behavior was difficult and regarding much endeavor although the motive was high, the frequency of the nursing behavior was rather low. But in the cases in which there was much self confidence and a high level of skill was required, nursing behavior was carried more frequently. When there was muck self confidence and skill was not required, the frequency of nursing behavior was rather low. In the cases of a high level of knowledge, the frequency of nursing behavior was low and when recognition for nursing behavior was given the frequency of nursing behavior was low.