• Journal of Korean Society for Quality Management
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• v.31 no.3
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• pp.185-192
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• 2003

In this paper, the properties on the optimal replacement policies for the general failure model are developed. In the general failure model, two types of system failures may occur : one is Type I failure (minor failure) which can be removed by a minimal repair and the other, Type II failure (catastrophic failure) which can be removed only by complete repair. It is assumed that, when the unit fails, Type I failure occurs with probability 1-p and Type II failure occurs with probability p, $0\leqp\leq1$. Under the model, the system is minimally repaired for each Type I failure, and it is repaired completely at the time of the Type II failure or at its age T, whichever occurs first. We further assume that the repair times are non-negligible. It is assumed that the minimal repair times in a renewal cycle consist of a strictly increasing geometric process. Under this model, we study the properties on the optimal replacement policy minimizing the long-run average cost per unit time.

• Management Science and Financial Engineering
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• v.6 no.1
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• pp.1-19
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• 2000

This papeer proposes a general approach of the multivariate expontially weighted moving average(MEWMA) chart, in which the smoothing matrix has full elements instead of only diagonal elements. The average run length (ARL) properties of this scheme are examined for a diverse set of quality control environments and the information to design the chhart is provied. Performance of the scheme is measured by estmating ARL and compared to those of two group cumulative sum (CUSUM) chats. The comparison resullts show that the MEWMA chart can improve its ARL performance in detecting a small shifts out-of-control in the start-up stage, the general MEWMA chart of a full smoothing matrix appears to offer an exceptional protection aginst departures from control in the process mean.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.340-345
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• 2000

This study was carried out to analyze the light and thermal environment in model greenhouse using infrared absorption film as shading screen and to compare with the case of no shading and using general shading screen such as aluminum foil-backed film, black polyethylene film and thermal blanket. PPFD(photosynthetic photon flux density) of inside the model greenhouse under infrared absorption film was increased by 22% than under general shading screen on the average. And temperature of inside air under infrared absorption film was 2$^{\circ}C$ lower than under general shading screen on the average. So, it is expected that infrared absorption film is useful as shading screen.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.383-394
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• 2001

This paper is a generalization of single and two-level skip-lot sampling plans to n-level. On every skipping inspection of the n-level skip-lot sampling plan, not only the number of consecutive lots to be accepted but also the fraction of lots to be inspected can be freely choosed. The general formulas of the operating characteristic function, average fraction inspected, average sample number and average outgoing quality in n-level skip-lot sampling plan are derived. The operating characteristic curves, average sample number and average outgoing quality of a reference plan, two-level and five-level skip-lot sampling plans are compared.

• Archives of Plastic Surgery
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• v.37 no.3
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• pp.265-270
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• 2010

Purpose: Most of the bilateral structures in our body are not perfectly balanced, such that one side is preferred than the other or it has physiological superiority. Eyes also have an imbalance; the eye with sensory and motional superiority compared to the other is called dominant eye. Authors of this study focused on analyzing the correlation between the dominant eye and levator palpebrae superioris muscle. Methods: The subject of this study was 42 patients with no ptosis and with no past history of blepharoplasty. Hand dominance was identified through questionnaire and dominant eye was identified by hole-in-the-card dominance test (Dolman's test) in all patients. The function of levator palpebrae superioris muscle was measured by MLD (marginal limbal distance). During the measuring procedure, frontalis muscle was not inhibited to avoid the eyelid skin hooding. Results: Out of 42 patients, 27 patients (64.3%) were right ocular dominant, 15 patients (35.7%) were left ocular dominant, 36 patients (85.7%) were right hand dominant and 4 patients (9.5%) were left hand dominant. Out of 27 right ocular dominant patients, right MLD was larger than the left in 26 patients (96.3%). It was larger in average of 0.47 mm (p<0.001) in 27 right ocular dominant patients. Also, left MLD was larger than the right in 11 patients (73.3%) out of 15 left ocular dominant patients. It was larger in average of 0.57 mm (p=0.003) in 27 left ocular dominant patients. MLD on the side of the dominant eye was larger in average of 0.50 mm (p<0.001) than the MLD of non-dominant eye side. Right MLD was larger than the left in average of 0.28mm (p=0.010) in right hand dominant patients, and left MLD was larger than the right in average of 1.15 mm (p=0.025) in left hand dominant patients. Conclusion: The function of levator palpebrae muscle differs in right and left, and the difference correlates with the dominant eye. Also, the function of levator palpebrae muscle is stronger in the dominant eye. We were able to present statistical evidence regarding the difference of the function in right and left levator palpebrae muscle. This may be a factor worth consideration in terms of balancing the eyes during the blepharoplasty.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.811-818
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• 2008

This paper is the generalization of the modified two-level skip-lot sampling plan(MTSkSP2) to n-level. The general formulas of the operating characteristic(OC) function, average sample number(ASN) and average outgoing quality(AOQ) for the plan are derived using Markov chain properties.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.3 no.1
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• pp.11-16
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• 2007

The use of general anesthesia as a special method of behavior management is necessary if certain handicapped or disabled child patient to receive dental treatment. This study was designed to report the results of 53 cases of complete oral rehabilitation under general anesthesia. The data were obtained from patients who were provided with dental treatment under general anesthesia for last 3years managed at the Dept. of pediatric dentistry in PNU Hospital. The distribution of age, gender, primary reason for general anesthesia, duration of dental procedure, number of treated tooth and periodic recall check-up were surveyed. In distribution of age, most(78%) were younger than 10 years and mean was 13.0 years. The reasons for providing general anesthesia were lack of cooperation due to various mental and physical handicapped situation(74%), congenital heart disease(13%), combined with medically compromised and behavior problem and others. The average duration of the treatments was 2 hours and 41 minutes and average duration of the anesthesia was 3 hours and 6minutes. The mean number of treated with restoration a children were 16.7 teeth. From the results, total dental rehabilitation under general anesthesia is a favorable modality to improve for disabled children's oral condition.

• Journal of Korean Academy of Nursing
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• v.34 no.1
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• pp.93-101
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• 2004

Purpose: This study was designed to explore the relationship of situational meaning with maternal self-esteem in mothers with high risk newborn. Method: The subjects of this study were 82 mothers with high risk newborn. Data were collected using a translated Family Meaning Attribution Scale and Maternal Self-Report Inventory. Data were analyzed using descriptive statistics, t-test, Pearson Correlation Coefficients and Stepwise Multiple Regression. Result: The average score of the situational meaning in high risk newborn mothers was 64.0l(possible score is between 0-96) and the average score of each item was 1.98. The average score of the maternal self-esteem in high risk newborn mothers was 81.96(possible score is between 26-104) and the average score of each item was 3.15. No significant differences were found in situational meaning according to general characteristics except whether it was a planned pregnancy or not. No significant differences were found in maternal self-esteem according to general characteristics except disease or admission experience during pregnancy. There was significant positive correlation between situational meaning and maternal self-esteem. Conclusion: It is necessary for nurses to provide high risk newborn mothers with care for improving situational meaning that is attributed to the mothers. It can be helpful to improve maternal self-esteem and in the end it will facilitate the maternal transition in mothers with high risk newborn.

• Journal of radiological science and technology
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• v.45 no.3
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• pp.205-211
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• 2022

This study aimed to provide basic data for 3D printing in the medical health field by developing upper wear fixation device (UWFD), an auxiliary device for shortening chest AP examination time on emergency room beds and non-contact with patients. The standard of hooks was modeled according to the bed frame using the Autodesk Fusion 360. It was printed with Form2 (Formlabs, Somerville, MA, USA), as SLA (stereo lithography apparatus) method, and was washed and hardened using Form Wash and Form Cure. The completed UWFD conducted an online survey on 4 items of stability, convenience, availability, preference and general characteristics. The total stability average was 3.93±0.80, the total convenience average was 3.93±0.68, the total availability average was 4.01±0.89, and the total preference average was 3.80±1.08. This study was significant in suggesting improvements in the general X-ray examination process in the emergency room by designing and making aids to easily fixing the patient's top to the frame of the emergency bed while meeting promptness and non-contact with the patient.

• Archives of Plastic Surgery
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• v.36 no.2
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• pp.147-152
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• 2009

Purpose: First web space contracture of the hand has been treated with various surgical techniques such as Z - plasty, local flap, pedicled flap, distant free flap, and anterolateral thigh free flap. Among those surgical techniques, anterolateral thigh free flap provide a thin and pliable flap, which is a useful method for correction of first web space contracture. Methods: From August 2003 to September 2007, authors selected 9 patients who had first web space contracture with limitation of thumb abduction within 30 degrees. All of patients had received first web contracture release with anterolateral thigh free flap. Age ranged from 24 to 51, and all the patients were male. Average follow up period was 12 months and authors performed photographic analysis of the thumb abduction angle of postoperative increase. Result: All the flaps were survived. Donor site was closed with primary closure in 8 cases and covered with split - thickness skin graft in 1 case. Average flap size was $8{\times}9cm$ and average thickness was 0.6 cm in suprafascial flap. The procedure resulted in increased thumb abduction angle of $34.7^{\circ}$ in average and showed concave shape of first web space in suprafascial flap. Additional operations were performed with Z - plasty in 3 cases, local flap in 5 cases, and opponensplasty in 3 cases. Conclusion: In suprafascial flap, we obtained relatively thin flap thickness and were able to make natural concave shape of first web space. In releasing severe contracture of the first web space, anterolateral thigh free flap provided a good coverage of appropriate thickness and pliable soft tissue and allowed limited donor site morbidity.