• International Journal of Highway Engineering
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• v.11 no.2
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• pp.85-98
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• 2009

The in-situ Compaction test using sand cone (RC) and Plate Bearing Capacity Test (PBT) has been widely used for evaluating the subgrade and subbase condition on the pavement system. However, because the in-situ RC and PBT test are expensive and take plenties of time for operation, these are very difficult to figure out the in-situ characteristics of subgrade and subbase strength in detail. Therefore, for faster and economical operation, this study is to compare the Light Falling Weight Tests and propose the LFWD test as the in-situ Compaction test. This study suggests the relationship between in-situ RC value, $K_{30}$, $M_R$ and $E_{LFWD}$ of the subgrade and subbase materials in Korea using the laboratory and in-situ testing.

• The Journal of Korean Society for School & Community Health Education
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• v.13 no.2
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• pp.107-118
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• 2012

Backgrounds: In order to prevent dental injuries that often occur in child and adolescent, it is intended to investigate and assess actual state of the injury development, present epidemiological background, and consider and discuss for preparing preventive means against the injury development. Purpose: It was attempted to understand major features of dental injuries developing in child and adolescent and indentify high risk factors of dental injuries in child and adolescent. Methods: In this study, 523 cases of computerized data collected as disease entities of dental injuries among 1-18 years old patient visiting S university hospital located in Seoul in 2009 were analyzed and following results were obtained. Results: It was found that the ratio of dental injuries by genders in child and adolescent was 66.14% of male and 33.86% of female. It was shown also that causes of dental injuries by ages were more in order of falling, bumping, chewing, traffic accident, sports, violence, and crash. In addition places where dental injuries occur by ages were home in less than 5 year old group, park, playground, and play yard in 6-11 year old group, park, playground, and play yard also in 12-14 year old group, and stairs, road, and outdoor places such as mountain climbing, beach, and camping in 15-18 year old group. It was found that time rages when dental injuries in child and adolescent often develop were 15-19 o'clock for falling, 15-19 o'clock for crash, 15-19 o'clock for bumping, 19-03 o'clock for violence, 15-19 o'clock for traffic accident, 15-19 o'clock for sports activity, and 15-19 o'clock for chewing. Conclusion: Background of dental injury inducing factors are very complicated and diversified, so deep study and analysis are required for its prediction. Therefore, it seems necessary to identify risk factors by phases such as before, at, and after accident, establish strategies to reduce injury development, and develop and utilize necessary programs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.11-15
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• 1988

Square slices of sea tangle was dried in constant condition of thickness (1.54mm), air temperature $(50^{\circ}C)$, relative humidity $(30\%)$ and air velocity (0.4m/s). The shrunk surface area and the shrinking rate were investigated. The results obtained are summarized as follows : 1) Comparing the shrinking of transverse section with that of vertical section, the transverse section was proceeded more double shrinkage than vertical section. 2) The shrunk surface area curve showed nearly a linear shrinkage up to 90min of drying time. 3) The shrinking rate was rapidly increased in first falling rate period, and was largest in the early period of second falling rate period.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1294-1303
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• 1999

The purpose of this study was to develop a tool to assess the powerlessness and to measure the powerlessness of elderly. From the result of pre-test, twenty seven items were finally selected to survey the elderly's powerlessness. The questionnaires on the elderly's powerlessness were drafted so that such tool may be evaluated in accordance with the four point Likert Scale. The number of subjects is 1,150 with ages of 60 years or more and who live in a large city, a small and middle-sized city and a rural area. The subjects of the test and retest were 85 elderlies. Collected data were analyzed by utilizing SAS program with Cronbach's $\alpha$ and Pearson's correlation, factor analysis method and known group techniques, descriptive statics, t-test and ANOVA. The results from this study were summarized below:1. When the factor analysis method was applied for validity, the tool for powerlessness of elderly was separated into 5 factors: loss of self-confidence to deal with physical, emotional, social aspects of life; expulsion by others from meaningful human relate; perception that life is meaningless and time passes quickly; falling behind young people; being rejected by other people, having no influence on others. An application of the known group technique showed a significant difference with the result of the degree of elderly's powerlessness tools developed by the two groups, with illness and without. 2. In testing reliability, it was found that coefficient of test-retest was .9435(P<.0001) when the test-retest method was used as a test of stability, and that the alpha coefficient of internal consistency was .9141 over all items within the tool of elderly's powerlessness 3. In powerlessness of elderly, total mean is 2.8493. And in factor of powerlessness, the highest factor is falling behind young people (M=3.1713), the lowest factor is loss of self- confidence to deal with physical, emotional, social aspects of life(M=2.6080). 4. The results from the test for the degree of powerlessness, according to the subject's demographic variables, showed that there were significant differences between age, sex, marital status, educational level, religion, possession of house, job, monthly pocket money, health status, illness and a place of residence.

• Explosives and Blasting
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• v.26 no.1
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• pp.15-21
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• 2008

In case of estimating the shocking vibration during the blasting demolitions, the weight and falling height of the structure, that is a potential energy, had been considered. But, this study presented a new equation which used the impulse concerning a falling weight instead of potential energy as a method of predicting the shock vibration. In this experiment, the data of the impulse were compared with the data of the potential energy by performing the free-fall, and all data were comparatively analyzed by the regression analysis method. Also, the method of the superposition theory, which is calculated by the diminution ratio according to distance, the free-fall difference according to height, and the time giving the shock to the ground according to the breakdown pattern, was compared with the previous vibration data occurring from the blasting demolitions in the same conditions. As a result, this study suggests that the impulse and the method of superposition theory be applied as a method of predicting the shocking vibration. Therefore, these results could be expected to estimate the shocking vibration more accurately than the previous method.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.1
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• pp.47-62
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• 2001

An experimental study was peformed to provide the numerical models to predict the physical fate of marine debris with the key information concerning their trifling and sinkage on the sea. For hygroscopic materials their floating times in a pseudo ocean environment were measured, and for non-hygroscopic objects their drifting limes in a certain wave condition were measured. For sinking materials or objects became to be sinkable free falling experiment was performed to evaluate their falling speed. Summarized information was condensed into a numerical model to predict the most possible region of a significant marine debris accumulation, and the seas connected to the Han river and the Nak-Dong river were considered for the simulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.64-69
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• 1992

To examine the effects of blanching treatments on the drying of hot red pepper, the pilot scale hot-air dryer equipped with the weight sensor using strain gauge type load cell and strain amplifier was designed and manufactured. The drying characteristic curves of cut hot red pepper showed a settling down period followed by a constant rate period and falling rate period, but blanched hot red pepper showed only falling rate period. According as the blanching time and temperature rises, the drying rates and the capsanthin contents of hot red pepper fairly increased. Considering the drying rates and the color values of dried hot red pepper, we suggest the desirable blanching condition of hot red pepper should be water blanching at $80^{\circ}C$ for 3 mins.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.61-67
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• 1977

Seed separation from half-cut red pepper were investigated with free falling, up-and-down shaking and rotating collision methods. The separation rates were related with impact appiied and the rotating case was distinguished from the other two methods. Beside the impact effect, velocity of the pod and tumbling factors were involved. Momentum effectiveness of seed separation were calculated as $2.50{\times}10^{-6}$, $2.09{\times}10^{-6}$, and $3.94{\times}10^{-8}$ for free falling, shaking and rotating method on the same velocity basis, respectively. The tendency of separation rate was similar to that of red pepper drying rate against time.

• Journal of Trauma and Injury
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• v.31 no.3
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• pp.117-124
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• 2018

Purpose: This study was to analyze clinical and epidemiological characteristics of elderly patients who were admitted to the emergency department (ED) due to falls by separating male and female. Methods: We retrospectively analyzed the fall patients aged 65 years or older from the data of the in-depth surveillance study of injured patients visit to the ED under the supervision of the Korea Centers for Disease Control and Prevention (KCDC) from 2011 to 2016 by separating male and female. Results: A total of 361,588 elderly fall patients were analyzed and, among them, 14,429 (37.3%) were males and 24,208 (62.7%) were females. Male and female showed similar frequency of damage happening season. However, they showed falling accident mostly on winter. The time of injury occurrence is mostly from 12:00 to 18:00 with 4,949 (34.3%) male and 8,564 (35.4%) female. Most falls occurred in daily activities, accounting for 7,614 (52.8%) in males and 14,957 (61.8%) in females, respectively. Unintentional damage accounted for the most part and 7,395 (51.2%) of male and 15,343 (63.4%) of female were injured indoors. Head and neck were the most common site of injuring, with 8,392 (58.2%) in males and 7,851 (32.4%) in females. According to ED examination outcomes, most of the patients were discharged, while the majority of the hospitalized patients were admitted to the general patient room. Conclusions: The elderly falls occurred mostly from 12:00 to 18:00, during winter and to elderly women. Also, they happened unintentionally indoors in everyday life, mostly. Proved clinical, epidemiological characteristics from this research will be used as useful indicator at validity research of development of prevent program of falling accident for elderly people.

• PNF and Movement
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• v.19 no.3
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• pp.435-440
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• 2021

Purpose: The purpose of this study is to investigate the effects of older adult's head-turn gait on gait parameters by comparing with head oriented forward gait and to provide criteria for their risk of falling compared to young adult. Methods: The subjects were 19 young adults in their 20s and 18 older adults in their 60s or above residing in Daegu or Gyeongsangbuk-do. To evaluate their gait parameters, spatiotemporal gait parameters were measured using a gait analysis tool (Legsys, BioSensics, USA) under two conditions: 1) walking while keeping one's eyes forward and 2) walking while turning the head. The measurement for each test was performed after one practice session, and the mean value of three measurements was analyzed. The collected data were statistically processed using a two-way analysis of variance (ANOVA) to compare any differences in gait parameters between the two groups under the two conditions. The statistical significance level was set at α=0.05. Results: According to the comparison of gait parameters in young adult and older adult between the head oriented forward gait and head-turn gait, statistically significant differences were observed in two parameters: stride length according to the height ratio and stride speed obtained by dividing the stride length according to the height ratio by time (p<0.05). Conclusion: The results of this study indicate that the head-turn gait causes greater differences in stride length and speed among older adult than in young adult and therefore can act as a cause of falling.