• The Journal of Korean Medicine
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• v.23 no.3
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• pp.1-10
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• 2002

Objective: There exist gender differences in pulsatile contour waveform. Women have a greater age-related increase in left ventricular mass than do men and more likely to experience symptomatic heart failure after infarction. SDPTG (the second derivative of photoplethysmogram waveform) is a noninvasive method for evaluating the pulse wave and is correlated with age and other risk factors for atherosclerosis. We studied the effect of gender on SDPTG and made clear why the gender differences appear. Methods: To study the effects of effect factors, including height and blood pressure, on SDPTG in the fourth decade, data on height, weight, PTD (pulse transit distance), blood pressure, serum lipid levels, and SDPTG were collected in 115 laboratory healthy men and women. SDPTG is derived from double-differential processing of fingertip photoplethysmography and consists of a, b, c, and d waves in systole and an e wave in diastole; SDPTG aging index (AI) was calculated as (b-c-d-e)/a. Results: There were significant gender-related differences of SDPTG AI, height, and blood pressure. Age, height, and mean blood pressure were respectively and significantly correlated with SDPTG AI. SDPTG is dependent upon age, height, and blood pressure. Restricting analysis to SDPTG AI, age, height, and mean blood pressure, yielded that there were gender-related differences in SDPTG AI (P<0.05) which were derived from those of height (F<0.001, df=l, P=0.994). Conclusions: These new data may help to explain previous findings about age-related differences in pulsatile contour waveforms and why gender differences of SDPTG appear. The results of this study suggest that SDPTG AI, used for evaluation of biological vascular aging, should be calibrated by height as well as age and blood pressure.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2567-2572
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• 2011

It is the key component that motor block system affect safety and performance of railway. It is very important to examine the performance of motor block for improvement of safety and reliability of rolling stock. As such, the motor block is an essential part of rolling stock. But provisioning quantities and spare quantities depend on the operator' experience. There are many problems that occur lots of spare or lack of spare. If there are lots of spare, it is difficult to keep the circumstance by cost issues. On the contrary, if there are lack of spare, it may have a adverse effect on the whole railway. Thus, this study offers method to estimate optimal spare of motor block using the analysis of data related with Failure rate, MTBF, standards and guidelines. And we expect this study to contribute to determine optimal spare parts.

• Structural Engineering and Mechanics
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• v.37 no.4
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• pp.427-442
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• 2011

In fatigue life design of mechanical components, uncertainties arising from materials and manufacturing processes should be taken into account for ensuring reliability. A common practice is to apply a safety factor in conjunction with a physics model for evaluating the lifecycle, which most likely relies on the designer's experience. Due to conservative design, predictions are often in disagreement with field observations, which makes it difficult to schedule maintenance. In this paper, the Bayesian technique, which incorporates the field failure data into prior knowledge, is used to obtain a more dependable prediction of fatigue life. The effects of prior knowledge, noise in data, and bias in measurements on the distribution of fatigue life are discussed in detail. By assuming a distribution type of fatigue life, its parameters are identified first, followed by estimating the distribution of fatigue life, which represents the degree of belief of the fatigue life conditional to the observed data. As more data are provided, the values will be updated to reduce the credible interval. The results can be used in various needs such as a risk analysis, reliability based design optimization, maintenance scheduling, or validation of reliability analysis codes. In order to obtain the posterior distribution, the Markov Chain Monte Carlo technique is employed, which is a modern statistical computational method which effectively draws the samples of the given distribution. Field data of turbine components are exploited to illustrate our approach, which counts as a regular inspection of the number of failed blades in a turbine disk.

• Journal of the Korea Safety Management & Science
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• v.15 no.3
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• pp.61-69
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• 2013

According to ISO 26262 (the international standard on functional safety for automotive industry), the functional safety should be considered during the whole automotive systems life cycle from the design phase throughout the production phase. In order to satisfy the standard, the automotive and related industry needs to take appropriate actions while carrying out a variety of development activities. This paper presents an approach to coping with the standard. Analyzing the standard indicates that the safety issues of the automotive systems should be handled with a system's view whereas the conventional approach to solving the issues has been practiced with focus on the component's level. The aforementioned system's view implies that the functional safety shall be incorporated in the system design from both the system's life-cycle view and the hierarchical view for the structure. In light of this, the systems engineering framework can be quite appropriate in the functional safety development and thus has been taken in this paper as a problem solving approach. Of various design issues, the analysis and verification of the safety requirements for functional safety is a key study subject of the paper. Note, in particular, that the conventional FMEA (failure mode effects analysis) and FTA (fault tree analysis) methods seem to be partly relying on the insufficient experience and knowledge of the engineers. To improve this, a systematic method is studied here and the result is applied in the design of an ABS braking system as a case study.

• Journal of the Korean Institute of Rural Architecture
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• v.4 no.3
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• pp.39-52
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• 2002

Some projects being in force by the Ministry of Government Administration & Home Affairs and the Ministry of Agriculture & Forestry for farm village area activation offers experience activity of various form to city dwellers, and to farm village inhabitants, affirmative effect is expected in aspect that activation becomes possible for a lot of visitors. But, to farm village(rural district) area activation that huge budget and effort carried out successfully, there are some items that specialist, administration and the persons concerned must inspect together now. First, to project for farm village area activation succeeds; leading participation of inhabitants should be premised. Second, that stagnated economy revives is as rightful result that appears in case farm village area activation effort succeeds. But, can drop more highlights like the value pursuit of life in case put success or failure of all businesses in income enlargement. Third, because inhabitant cultivates own in making process, the attachment and pride for area can be inculcated. Doing not become focus is set to economical logic to do, the heritage of area as well as history culture, must consider that apply eco-museum concept that magnify nature heritage and industry heritage. Fourth, actually the plan period given usually is too shortly than received huge budget. Furthermore, in case it carries out by desirable inhabitants leading type so. Project that not consider the period that is cost to the statement of inhabitants' active opinion and finding out a point of compromise may be hard to get desirable result.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7359-7363
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• 2015

Background: As a result of significant progress made in treatment of many types of cancers during the last few decades, there have been an increased number of patients who do not experience mortality. We refer to these observations as cure or immune and models for survival data which include cure fraction are known as cure rate models or long-term survival models. Materials and Methods: In this study we used the data collected from 438 female patients with breast cancer registered in the Cancer Research Center in Shahid Beheshti University of Medical Sciences, Tehran, Iran. The patients had been diagnosed from 1992 to 2012 and were followed up until October 2014. We had to exclude some because of incomplete information. Phone calls were made to confirm whether the patients were still alive or not. Deaths due to breast cancer were regarded as failure. To identify clinical, pathological, and biological characteristics of patients that might have had an effect on survival of the patients we used a non-mixture cure rate model; in addition, a Weibull distribution was proposed for the survival time. Analyses were performed using STATA version 14. The significance level was set at $P{\leq}0.05$. Results: A total of 75 patients (17.1%) died due to breast cancer during the study, up to the last follow-up. Numbers of metastatic lymph nodes and histologic grade were significant factors. The cure fraction was estimated to be 58%. Conclusions: When a cure fraction is not available, the analysis will be changed to standard approaches of survival analysis; however when the data indicate that the cure fraction is available, we suggest analysis of survival data via cure models.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8259-8263
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• 2014

Aims: To determine the clinical characteristics, pathological features, local and distant failure patterns in patients with carcinoma of major salivary glands treated with surgery and postoperative radiotherapy (PORT). Materials and Methods: We retrospectively reviewed 106 cases of major salivary gland tumor seen at our centre (1998-2008). Sixty five cases of major salivary gland carcinoma were selected for analysis (exclusions: benign, palliative, non-carcinomas). The patient population treated by surgery and PORT was divided into two groups: 1) Patients who underwent surgery and immediate PORT (Primary PORT); 2) Patients with recurrent carcinoma who underwent at least two surgeries and received PORT in the immediate post-operative period of the last performed surgery (Recurrent PORT). Recurrence free survival (RFS) was assessed using the Kaplan-Meier method. Results: Median age was 35 years with a male: female ratio of 1.3:1. The majority of cancers were located in the parotid gland (86.2%) and the most common histology was mucoepidermoid carcinoma (43%). Thirty nine cases (60%) were primary while 26 (40%) were recurrent. Optimal surgery was performed in 59/65 patients (90.8%). 43 patients (66.2%) underwent neck dissection, of which 14 (32.5%) had nodal metastasis. Overall, 61 (93.8%) patients complied with the prescribed radiotherapy. Median dose of PORT was 60 Gy. Median follow-up was 13.1 months (range 2-70). Relapse free survival was 50.4% at 60 months. Some 12 cases (18.5%) recurred with a median time to recurrence of 16.9 months. Conclusions: Surgery and PORT is an effective treatment for major salivary gland carcinoma with over 90% compliance and <20% recurrence. Early treatment with postoperative radiotherapy may increase the survival rate in major salivary gland carcinoma patients.

• Journal of architectural history
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• v.7 no.3 s.16
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• pp.137-149
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• 1998

The purpose of this study is to learn from a lesson of the historical fact, the Team 10's break away from the CIAM, which is selected as the most important event in the whole 20th century architecture by author as a historian. The CIAM, organized in 1928 by leading European architects in order to propose new architecture in the industrial era, expanded to the world, met almost annually with an idea of economic efficiency, new functional order, and industrial production for thirty years. Young architects had conflicted with old established group from 6th congress, and after 10th congress they met independently in 1959; the CIAM was disappeared and the Team 10 was born. Main issue of the break-away was human aspect. The Team 10 started from real man, concept of 'human contact', 'sense of community', and 'belonging' instead of abstract functional order. Although CIAM did not suggest inhumane architecture, their biological criteria with sunlight, air, sufficient site became physical determinism. Critique against the Team 10, unsuccess for making humane architecture leads to underestimation like a generational hegemony struggle. However, architect is not specialist of life but form. Historical reevaluation for Team 10 should be that they are the first group to raise an human issue in architecture. Success or not to solve the problem belongs to another domain. After 1960, modern architecture was attacked from the common people, not clients but 'users'. Academic circle tried to solve the problem with behavioral approach through a clear process, 'design method' and with phenomenological approach on real human experience. However practice became reactionary tendency, to make form a little complex, they became post-modern and deconstruction form. Failure of the Team 10's form proved that a complex form does not necessarily make a good life of people. In the Korean historic situation of colony ruling, confusion of liberation, and the War, we did not know the existence of both CIAM and Team 10. After 1970s' economic development, we have just copied Western form from Modern via Post-Modern to Deconstruction. If we make architecture people mattered, we should start from the basic, learning from the Team's break-away, instead of copying.

• Radiation Oncology Journal
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• v.34 no.4
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• pp.260-264
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• 2016

Purpose: Stereotactic body radiotherapy (SBRT) takes advantage of low ${\alpha}/{\beta}$ ratio of prostate cancer to deliver a large dose in few fractions. We examined clinical outcomes of SBRT using CyberKnife for the treatment of low- and intermediate-risk prostate cancer. Materials and Methods: This study was based on a retrospective analysis of the 33 patients treated with SBRT using CyberKnife for localized prostate cancer (27.3% in low-risk and 72.7% in intermediate-risk). Total dose of 36.25 Gy in 5 fractions of 7.25 Gy were administered. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored. Results: Thirty-three patients with a median 51 months (range, 6 to 71 months) follow-up were analyzed. There was no biochemical failure. Median PSA nadir was 0.27 ng/mL at median 33 months and PSA bounce occurred in 30.3% (n = 10) of patients at median at median 10.5 months after SBRT. No grade 3 acute toxicity was noted. The 18.2% of the patients had acute grade 2 genitourinary (GU) toxicities and 21.2% had acute grade 2 gastrointestinal (GI) toxicities. After follow-up of 2 months, most complications had returned to baseline. There was no grade 3 late GU and GI toxicity. Conclusion: Our experience with SBRT using CyberKnife in low- and intermediate-risk prostate cancer demonstrates favorable efficacy and toxicity. Further studies with more patients and longer follow-up duration are required.

• Journal of Chest Surgery
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• v.50 no.5
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• pp.317-325
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• 2017

Background: Extracorporeal membrane oxygenation (ECMO) has become an important treatment modality in pediatric patients with cardiopulmonary failure, but few studies have been conducted in Korea. Methods: We conducted a retrospective review of pediatric patients younger than 18 years who were placed on ECMO between January 2004 and December 2014 at Samsung Medical Center. Results: We identified 116 children on ECMO support. The overall rate of successful weaning was 51.7%, and the survival to discharge rate was 37.1%. There were 39, 61, and 16 patients on ECMO for respiratory, cardiac, and extracorporeal cardiopulmonary resuscitation, respectively. The weaning rate in each group was 48.7%, 55.7%, and 43.8%, respectively. The survival rate was 43.6%, 36.1%, and 25.0%, respectively. Sixteen patients on ECMO had functional single ventricle physiology; in this group, the weaning rate was 43.8% and the survival rate was 31.3%. Ten patients were on ECMO as a bridge to transplantation (8 for heart and 2 for lung). In patients with heart transplantation, the rate of survival to transplantation was 50.0%, and the overall rate of survival to discharge was 37.5%. Conclusion: An increasing trend in pediatric ECMO utilization was observed. The outcomes were favorable considering the early experiences that were included in this study and the limited supply of specialized equipment for pediatric patients.