• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.2
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• pp.206-212
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• 2008

Purpose: This study was done to identify the effects of self-care behavior, self-efficacy and family support on the occurrence of peritonitis in patients on CAPD (Continuous Ambulatory Peritoneal Dialysis). Methods: Data were collected from 81 patients on CAPD either as out-patients or in-patients between July and September 2004. Data were analyzed to identify relevant frequencies, percentages, averages, and standard deviations, and t-test and logistic regression were done using SPSS WIN 10.0 Results: a) Mean score for self-care behavior was 2.9 (of a possible 4.0), for general self-efficacy, 3.2 (of a possible 5.0), for specific self-efficacy 3.5 (of a possible 5), and for family support, 3.7 (of a possible 5). Family support generally showed the most positive results. b) Occurrence of peritonitis was not affected by general characteristics. c) There was a significant difference in the occurrence of peritonitis in terms of self-efficacy. Patients with peritonitis had lower self-efficacy than those who did not. 4) Of the four factors reviewed in relation to peritonitis, only self-efficacy was statistically significant: an increase in self- efficacy by 1 point increased the occurrence of peritonitis by 0.90. Conclusion: Among the four factors potentially affecting peritonitis in CAPD patients, general self-efficacy was found to be the main factor influencing the occurrence of peritonitis.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.40-49
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• 2019

In this paper, failure probabilities of the OPR1000 reactor vessel under pressurized thermal shock (PTS) were estimated using the probabilistic fracture mechanics code, R-PIE. Input variables of initial crack distribution, crack size, copper contents, and upper shelf toughness were selected for the sensitivity analyses. A wide range of the input data were considered. Through-wall cracking frequencies determined by the product of the vessel failure probability and the corresponding occurrence frequency of the transient were also compared to the acceptance criterion. The results showed that transient history had the most significant impact on the vessel failure probability. Moreover, conservative assumptions resulted in extremely high through-wall cracking frequencies.

• Structural Engineering and Mechanics
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• v.8 no.3
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• pp.285-297
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• 1999

A method is presented to find the location and magnitude of damage in a structure using data from dynamic tests. The test data include a combination of natural frequency measurements, taken before and after the occurrence of damage, and response measurements taken after damage. An algorithm is developed to identify localized increases in the flexibility of the structural members. Increases in flexibility are attributed to damage. The algorithm uses the sensitivity of the flexibility matrix to changes in the natural frequencies of the structure to identify the damage. A set of under determined equations is solved using an objective function which is derived from measurements of the system moments. Damage ranging from 10 to 60% increase in the flexibility of a member was successfully identified in a 50 d.o.f. structure, using a small number of natural frequency and velocity measurements.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.216-221
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• 2005

Many tanks such as a fresh water tank, an aft peak tank and oil tanks are arranged in the engine room and aft part areas of the ship. By added mass effect of the fluid inside the tanks, the natural frequency will be changed according to filling height of the tank. For this reason, there is possibility of occurrence of excessive vibration by resonance between natural frequencies of local structure and excitation frequencies of the propeller or main engine. Therefore, calculation of natural frequencies is required for structure for many types of tank which are contacting with water or oil to consider added mass effect for anti-resonance design at design stage. In this study, a case of structure damage on the fresh water tank for 2600 TEU container vessel is introduced. In addition, natural frequency analysis and vibration measurement have been performed to investigate vibration characteristics for excessive vibration control.

• Structural Monitoring and Maintenance
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• v.9 no.2
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• pp.201-220
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• 2022

Lateral vibrations of footbridges may induce synchronization between pedestrians and structure itself, resulting in amplification of such vibrations, a phenomenon identified by lock-in. However, investigations about accelerations and frequencies of the structural movement that are related to the occurrence of synchronization are still incipient. The aim of this paper is to investigate conditions that could lead to avoidance of synchronization among pedestrians themselves and footbridge, expressed in terms of peak acceleration. The focus is on the low acceleration range, employed in some guidelines as a criterion to avoid synchronization. An experimental campaign was carried out, employing a prototype footbridge that was set into oscillatory motion through a pneumatic exciter controlled by a fuzzy system, with controlled frequency and amplitude. Test subjects were then asked to cross the oscillating structure, and accelerations were simultaneously recorded at the structure and at the subject's waist. Pattern and phase differences between these signals were analysed. The results showed that test subjects tended to keep their walking patterns without synchronization induced by the vibration of the structure, for structural peak acceleration values up to 0.18 m/s², when frequencies of oscillation were around 0.8 to 0.9 Hz. On the other hand, for frequencies of oscillation below 0.7 Hz, structural peak accelerations up to 0.30 m/s² did not induce synchronization.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.267-268
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• 2012

To evaluate the incoming salt quantitatively which is the reason of salt attack is a very important aspect to calculate the durability life of the structure. Incoming salt is influenced by various weather changes during the transmission and consequently, the changes of incoming salt quantity occur. Therefore, the study to analyze incoming salt quantity was executed which are changed by the weather environments (occurrence frequency of wind direction / wind speed); study results showed that influences to the changes of incoming salt quantity are bigger than those of wind speed, compared with the frequencies.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.4
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• pp.379-385
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• 1998

The Holzworth's method was applied to estimate the daily maximum mixing height (DMMH) in Pohang, Osan and Kwangju areas. The data-base were established with meteorological data collected at air bases in these areas during the period 1983∼1992. It was investigated the seasonality, monthly trends and occurrence frequencies of the estimated DMMH data in each area. The estimated mean DMMH were found in the range of 1,100 m (winter) to 1,450m (spring). These mean DMMH data showed a typical seasonality in which higher values are commonly seen during spring and fall, while lower values during summer and winter seasons. An occurrence of estimated mean DMMH which in the range of 1,000∼2,000m altitude was appeared to be about 60%.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.3
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• pp.202-208
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• 1997

The knocking is one of major parameters to improve engine performance in a spark ignition engine. Many researches have been carried out to identify them using cylinder pressure, vibration signal and so on. In the present study, measurement and analysis was conducted to set up the criteria of knock occurrence by using microphone signal. Cylinder pressure was measured for the reference signal of knocking. It has been observed that resonance frequencies of pressure wave are nearly independent of engine operating conditions such as engine speed, air fuel ratio, load and octane number of fuel within to limited experimental conditions. SDBP(sum of different band-pass data) method using resonance frequency of knock was proposed for estimating knock intensity. SDBP method is superior to identify knock occurrence and its intensity in case of sound pressure measurement.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.461-470
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• 2018

The frequency of extreme weather events was analyzed using meteorological data (air temperature, precipitation, and duration of sunshine) collected from 61 stations over a 36-year span (1981-2016). The 10-day meteorological data were used as a basic unit for this analysis. On average, the frequency of occurrence of abnormal weather was 9.88 per year and has increased significantly during this 36-year period. According to the type of abnormal weather, the frequencies of occurrence of abnormally high air temperature and short duration of sunshine have increased by 0.50 and 0.41 per 10 years, respectively; however, that for abnormally low air temperature has decreased by 0.31 per 10 years and the trend was statistically significant. The highest frequency of abnormal weather appeared in 2007, with a frequency of 14.31. Abnormal weather was the most frequent at Yeongdeok station with an average frequency of 11.78 per year over this 36-year span.

• Safety and Health at Work
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• v.9 no.3
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• pp.308-313
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• 2018

Background: A behavior-based safety initiative card-issuing system was introduced at a cement-manufacturing company in Zimbabwe in 2008 to try and curb accident occurrence. The purpose of this study was to evaluate the effectiveness of the Behaviour Based Safety Initiative card system as a tool used for reducing accident frequencies. Methods: A mixed-method approach that involving administering piloted questionnaires to 40 out of 244 randomly selected employees, making observations, and reviewing secondary data were done to collect data from different sources in the organization in 2013. A paired t-test was conducted to test whether there was significant difference in accident occurrence before and after the implementation of the BBSI. Scatterplots were also used to establish the correlation between the issuance of cards and the accident and injury occurrence. Results: The findings suggest that the introduction of the card system brought a significant decrease in accident and injury occurrence. A negative correlation between card issuance and accident occurrence was observed, i.e., the greater the number of cards issued, the fewer the number of accidents. It was also noted that the card system positively influenced the mindset of workers towards safe work practices. Conclusion: The card system had an influence on the reduction of accidents and injuries. The organization should leverage on issuing more cards to further reduce the number of accidents and injuries to zero.