• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.79-88
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• 2012

Small amount of salt and various microorganisms are contained in natural soils or clays near the shore. In this study, most common clay minerals such as kaolinite and bentonite are used to evaluate the effect of salt and microorganism on liquid and plastic limits. The effect of time after mixing clays with water was also investigated for the consistency limits of clays. The test was conducted immediately, 1 day, or 7 days after mixing soils. For liquid limit tests two different test methods were used, the percussion cup method by Casagrande and the fall cone method. When sea water or microbial solution was used for mixing soils rather than distilled water, the liquid limit of kaolinite decreased by 6-15% and that of bentonite further decreased up to 37-53%. The liquid limit obtained from the fall cone method was approximately 10% for bentonite and 20% for kaolinite, which are higher than those from the percussion cup method. The effect of time on liquid and plastic limits was significant for those tested immediately or 1 day later but the values obtained after 1 day or 7 days did not vary a lot, regardless of soils, mixing waters or test methods.

• Korean Journal of Construction Engineering and Management
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• v.19 no.3
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• pp.3-10
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• 2018

In recent years, mechanized construction has become commonplace due to increases in the scale and complexity of construction, and construction machinery is a major factor in successful construction. However, even though the proportion of construction machinery is increasing, analysis of the work capacity of construction machinery is inadequate. In addition, since the standards for all construction machines are currently not defined in quantity-per-unit, the construction period is arbitrarily applied according to the operator at the time of the construction plan. As a result, the construction period of the actual construction is insufficient, and rushed work or construction delays occur. Therefore, in this study, in order to calculate the construction period of the piling work of the pile driver used in the PRD method more accurately than the existing method, the formula for calculating the time required for the piling work of the pile driver was established by collecting piling time data from the daily task reports through the field survey. If the precise construction period of piling work is estimated based on the results of this study, it will be possible to prevent the rushed work and construction delays that occur due to the short construction period.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.313-320
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• 2022

The light buoy installed on the sea is always flexible, because it is affected by the weather as well as passing vessels. The position of the light buoy can be cached through the AtoN AIS (Automatic Identification System) and RTU (Remote Terminal Unit). This study analyzed the position data of the light buoys for the last five years (2017-2021), as well as the distribution of the light buoys within the maximum separated position. As a result, there was a basic error of 17.9% in the position data. Additionally, the separated position error of 197 light buoys to be analyzed was 70.64%, and the AtoN RTU was worse than the AtoN AIS by equipment. On the other hand, as a result of the plotting the position data of the light buoy, it was classified into four types. The most common percussion center type, the percussion center dichotomous type in which the position is divided into two zones based on the chimney, the central movement type with a fluctuating center, and the drag type, in which the position is deviated from the center for a certain period. Except for Type-1, the type was determined according to the position at which the light buoy was installed. This study is the first to analyze the position data of the light buoy, and it is expected that it will contribute to the improvement of the quality of the position data of the light buoy.

• (The) Research of the performance art and culture
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• no.39
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• pp.637-667
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• 2019

I have researched in the field the religious and performance culture of Indonesia through the musical iconography of Borobudur. There are many kinds of musical instruments which belong to India or Indonesia, performers being either court or folk musicians. Contemporary south-east Asian Indonesia has a broad religious heritage. Most of the population is Muslim, but the culture and customs are rooted in Indian Ramayana. I discovered, for example, the same percussion instruments played on a person's knees. I also came across similar string instruments with long and elliptical resonance casks on the iconography of the Incense Burner and Byam temple stone pagoda of Beakje dynasty in Korea and in Borobudur in Indonesia. The two musical instruments can not be found in other countries, such as Silla, Koguryŏ, China or the silk road area, but only Indonesia or India. This suggests that Beakje Buddhism is from the southern regions rather than China. I also discovered the same dancing motion with the court performers on the iconography of Borobudur, and the same musical instrument and performance in the Gamelan in today's Indonesian performance. Despite a disjuncture between the people and their past, the Shailendra Buddhism is alive in people's life and culture in the present day. So we can discover some familiarities between Indonesia's Gamelan and the percussional performance in Korean Buddhist rituals.

• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.95-102
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• 1999

The purpose of this study was to observe histopathologically the influence of advanced periodontitis on pulp tissue, and to conclude the correlation between the results with clinical manifestations. The samples were teeth with over 7mm pocket depth and over 50% radiographic bone loss. These were diagnosed to have very poor prognosis and thus planned to be extracted. Those with any of following conditions were excluded from the samples, loss of vitality, periapical pathology, restoration or prosthesis, dental caries, and attrition or abrasion. It was because these conditions could affect pulp without any correlation with periodontal disease. For the experiment, 17 teeth from 11 patients were selected. Average age of patient was 47. Each tooth was examined for following categoris; pocket depth, gingival recession, electric pulp test, mobility, percussion test, sensitivity test. The extracted teeth were fixed buffered neutral formalin solution. It was decalcified using 4% nitric acid. Sliced histological samples observed using light microscope, for pulp status, and severeity of inflammation. 4 samples were excluded due to histologic sample discrepency. Thus 13 samples were subject to observation. 4 showed normal conditions. Focal reversable pulpitis was shown in 5 samples. Chronic pulpitis was observed 1 sample. Pulpal abscess was observed in 3 samples.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.10
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• pp.1869-1876
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• 1992

The effect of particle property on FOD(foreign object damage) and strength degradation in structural ceramics especially, silicon carbide was investigated by accelerating a spherical particle having different material and different size. The damage induced showed significant differences in their patterns with increase of impact velocity. Also percussion cone was formed at the back part of specimen when particle size became large and its impact velocity exceeded a critical value. The extent of ring cracks was linearly related to particle size, however the impact of steel particle produced larger ring cracks than that of SiC particle. Increasing impact velocity the residual strength showed different degradation behaviors according to particle and its size. In the region the impact site represents nearly elastic deformation behavior, the residual strength was dependent upon the depth of cone crack regardless of particle size. However in elastic- plastic deformation region, the radial cracks led to rapid drop in residual strength.

• Archives of Reconstructive Microsurgery
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• v.10 no.1
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• pp.7-11
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• 2001

Purpose : To evaluate the neurologic abnormalities in the donor limb after contralateral C7 transfer in brachial plexus injury. Materials and Methods : From August 1996 to December 1999, five patients with brachial plexus injury were treated with contralateral C7 nerve root transfer. The average follow up was 16 months(range, 5 to 36 months). The clinical findings were assessed using the British Medical Research Council Grading System, and also measured grip power, pinch power of hand and two point discrimination of the fingers. Results : We had no difference in shoulder abduction and elbow flexion after contralateral C7 transfer. The grip and pinch strength were recovered within 4weeks. Sensory loss occurred in all patients and was noted to be more severe on index and middle finger. Four patients recovered within 2 weeks, one continued till one year. Subjective numbness and pain on percussion minimally persisted until last follow-up. Conclusion : The division of the C7 nerve root resulted in minimal and temporary functional deficit in the donor upper limb.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.1-7
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• 2006

Nowadays, out of other transmission parts, the sleeve is getting more and more important part for exact and smooth shifting from gear ratio change whenever drivers are needed. To exact and smooth shifting when drivers are needed, all the parts connected with gear shifting should be machined exactly and having dimensions designers are intended. Especially, in case of the sleeve that the most important functional part to shift from gear ratio change that drivers are intended, it needs high precision grade and quality in both sides runout and outer dia runout as well as inner spline small dia & large dia. Because it's assembled with the synchro hub spline and shifted directly with the mating cone. So, it should be applied the hear treatment(hereinafter referred to H.T.M.T) to prevent the friction and percussion loss from shifting with mating cone. At this time, the deformation problems are raised from almost H.T.M.T. process and it makes the inferior part.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.227-238
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• 1993

IRRI Engineering Division has developed a well drilling rig attachment that matched power tiller or hand tractor. It was designed in response to the growing demand for ground water utilization for small-scale irrigation, especially in drought-sticken and rained farms in Asian countries. The power tiller-driven rig can drill 30 meters of 100mm well in an unconsolidated formation in one day and can be rapidly converted from rotary to jetting or to the percussion method of drilling to suit different soil and rock formation. In addition, the power tiller can be quickly installed or removed from the rig frame and can be used for transporting the rig to other sites. The rig can be dismantled into smaller sub-assemblies for carrying by hand into less accessible areas. One manufacturer in Central luzon Philippines has started to produce the rig for well drillers in Central Luzon. The Department of Agriculture in the Philippines have procured thirty three(33) units of these machines f r their Shallow Tubewell program.

• Journal of Korean Clinical Nursing Research
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• v.14 no.3
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• pp.47-59
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• 2008

Purpose: The purpose of the study was to compare the active pain management (APM) with structured physiotherapy (SPT) with the conservative care on postoperative pulmonary complications, pain, and comfort in children under three year. Method: A non-equivalent control group, non-synchronized design study was used. A total of 64 children participated in the study. The children in the experimental group (n=32) received APM with SPT after surgical operation. After transferred to the general unit, the parents were instructed to hold the child for 30 minutes to relieve anxiety and have him/her sleep comfortably for 2 hours. Scheduled 20 minutes chest percussion was performed by the parents for 2 days: twice every 4 hours, one in 6 hours, then one every 8 hours for the rest of two days. Analgesic was administered as needed. Pain and comfort were observed and recorded by nurses using the FLACC and COMFORT Behavior Scale. Results: One child in the control group was diagnosed with postoperative pneumonia. The children in the experimental group who were received the APM with SPT reported higher scores in comfort and lower scores in pain than those in the control group. Conclusion: The findings suggest that APM with SPT can help prevent postoperative pulmonary complications and pain.