• Journal of Trauma and Injury
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• v.21 no.2
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• pp.108-114
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• 2008

Purpose: Using a propensity analysis, a recent study reported that blood transfusion might not be an independent predictor of mortality in critically ill patients, which contradicted the results of earlier studies. This study aims to reveal whether or not blood transfusion is an independent predictor of mortality in trauma patients. Methods: A total of three hundred fifty consecutive trauma patients who were admitted to our emergency center from January 2004 to October 2005 and who underwent an arterial blood gas analysis and a venous blood analysis were included in this study. Their medical records were collected prospectively and retrospectively. Using a multivariate logistic analysis, data on the total population and on the propensity-score -matched population were retrospectively analyzed for association with mortality. Results: Of the three hundred fifty patients, one hundred twenty-nine (36.9%) received a blood transfusion. These patients were older (mean age: 48 vs. 44 years; p=0.019) and had a higher mortality rate (27.9% vs. 7.7%; p<0.001). In the total population, the multivariate analysis revealed that the Glasgow coma scale score, the systolic blood pressure, bicarbonate, the need for respiratory support, past medical history of heart disease, the amount of blood transfusion for 24 hours, and hemoglobin were associated with mortality. In thirty-seven pairs of patients matched with a propensity score, potassium, new injury severity score, amount of blood transfusion for 24 hours, and pulse rate were associated with mortality in the multivariate analysis. Therefore, blood transfusion was a significant independent predictor of mortality in trauma patients. Conclusion: Blood transfusion was revealed to be a significant independent predictor of mortality in the total population of trauma patients and in the propensity-score-matched population.

• Journal of Gastric Cancer
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• v.19 no.2
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• pp.212-224
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• 2019

Purpose: Splenic hilar lymph node dissection (LND) during total gastrectomy is regarded as the standard treatment for proximal advanced gastric cancer (AGC). This study aimed to investigate whether splenic hilar LND or D2 LND is essential for proximal AGC of pT2- 4aN0M0 stage. Materials and Methods: Data of curative total gastrectomies (n=370) performed from 2000 to 2010 for proximal AGC of pT2-4aN0 stage were retrospectively reviewed. Clinicopathological characteristics and long-term outcomes were compared using propensity score matching between patients who underwent splenectomy (n=43) and those who did not (n=327) and between patients who underwent D2 LND (n=122) and those who underwent D1+ LND (n=248). Results: Tumors of larger size and a more advanced T stage and significantly lower overall and relapse-free survival (P<0.001) were observed in the splenectomy group than in the 2 spleen-preserving groups. Before propensity score matching, worse overall and relapse-free survival (P<0.001) was observed in the splenectomy group than in the non-splenectomy group. After matching, although the overall survival became similar (P=0.123), relapse-free survival was worse in the splenectomy group (P=0.021). Compared with D1+ LND, D2 LND had no positive impact on the overall (P=0.619) and relapse-free survival (P=0.112) after propensity score matching. Conclusions: Splenic hilar LND with or without splenectomy may not have an oncological benefit for patients with pathological AGC with no LN metastasis.

• Journal of Digital Convergence
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• v.17 no.5
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• pp.157-165
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• 2019

The objective of this study is to identify the relationship between tourists' intention upon UTAUT and purchase intention on tourism omnichannel considering moderating effect of trust and purchase propensity. As the results, 1) there are partially significant and positive relationship between tourists' intention and purchase intention. There are partially significant and positive moderating effect of 2) trust and 3) purchase propensity upon the relationship between tourists' intention and purchase intention on tourism omnichannel. In order to increase the purchase intention of diversified customers, it is necessary to secure the reliability of OmniChannel which integrates the on-off line, for the future, more in-depth study of purchase propensity of tourism omnichannel should be needed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.1
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• pp.71-82
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• 2022

Most of the predictions using machine learning are neutral predictions considering the symmetrical situation where the predicted value is not smaller or larger than the actual value. However, in some situations, asymmetric prediction such as over-prediction or under-prediction may be better than neutral prediction, and it can induce better judgment by providing various predictions to decision makers. A method called Asymmetric Twin Support Vector Regression (ATSVR) using TSVR(Twin Support Vector Regression), which has a fast calculation time, was proposed by controlling the asymmetry of the upper and lower widths of the ε-tube and the asymmetry of the penalty with two parameters. In addition, by applying the existing GSVQR and the proposed ATSVR, prediction using the prediction propensities of over-prediction, under-prediction, and neutral prediction was performed. When two parameters were used for both GSVQR and ATSVR, it was possible to predict according to the prediction propensity, and ATSVR was found to be more than twice as fast in terms of calculation time. On the other hand, in terms of accuracy, there was no significant difference between ATSVR and GSVQR, but it was found that GSVQR reflected the prediction propensity better than ATSVR when checking the figures. The accuracy of under-prediction or over-prediction was lower than that of neutral prediction. It seems that using both parameters rather than using one of the two parameters (p_1,p_2) increases the change in the prediction tendency. However, depending on the situation, it may be better to use only one of the two parameters.

• Journal of Korea Entertainment Industry Association
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• v.13 no.6
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• pp.307-317
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• 2019

This study is to investigate the effects of sensation seeking propensity of sports participants on the social support and exercise obsession. In order to achieve the objective of this study was to collect data to target the 250 people who regularly participate in sport in Seoul. The data collected by utilizing SPSS WIN 18.0 and AMOS 18.0 statistical reliability and to perform confirmatory factor analysis, a multivariate analysis, correlation analysis, multiple regression analysis, the following results were obtained. As a result of the analysis, First, there were statistically significant differences among the variables according to demographic characteristics. Second, there was a statistically or negatively related relationship among the measured variables. Third, the sensory pursuit propensity had a statistically significant effect on social support and exercise obsession. Finally, social support had a statistically significant effect on exercise obsession.

• Journal of Trauma and Injury
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• v.37 no.1
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• pp.6-12
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• 2024

Purpose: Open pelvic bone fractures are relatively rare and are considered more severe than closed fractures. This study aimed to compare the clinical outcomes of open and closed severe pelvic bone fractures. Methods: Patients with severe pelvic bone fractures (pelvic Abbreviated Injury Scale score, ≥4) admitted at a single level I trauma center between 2016 and 2020 were retrospectively analyzed. Patients aged <16 years and those with incomplete medical records were excluded from the study. The patients were divided into open and closed fracture groups, and their demographics, treatment, and clinical outcomes were compared before and after 1:2 propensity score matching. Results: Of the 321 patients, 24 were in the open fracture group and 297 were in the closed fracture group. The open fracture group had more infections (37.5% vs. 5.7%, P<0.001) and longer stays in the intensive care unit (median 11 days, interquartile range [IQR] 6-30 days vs. median 5 days, IQR 2-13 days; P=0.005), but mortality did not show a statistically significant difference (20.8% vs. 15.5%, P=0.559) before matching. After 1:2 propensity score matching, the infection rate was significantly higher in the open fracture group (37.5% vs. 6.3%, P=0.002), whereas the length of intensive care unit stay (median 11 days, IQR 6-30 days vs. median 8 days, IQR 4-19 days; P=0.312) and mortality (20.8% vs. 27.1%, P=0.564) were not significantly different. Conclusions: The open pelvic fracture group had more infections than the closed pelvic fracture group, but mortality was not significantly different. Aggressive treatment of pelvic bone fractures is important regardless of the fracture type, and efforts to reduce infection are important in open pelvic bone fractures.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.2
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• pp.220-228
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• 2024

Backgrounds/Aims: Postoperative pancreatic fistula is the key worry in the ongoing debate about the safety and effectiveness of total laparoscopic pancreaticoduodenectomy (TLPD). Laparoscopic-assisted pancreaticoduodenectomy (LAPD), a hybrid approach combining laparoscopic resection and anastomosis with a small incision, is an alternative to TLPD. This study compares the short-term outcomes and oncological efficacy of LAPD vs. open pancreaticoduodenectomy (OPD). Methods: A retrospective analysis of data of all patients who underwent LAPD or OPD for periampullary carcinoma at a tertiary care center in Northeast India from July 2019 to August 2023 was done. A total of 30 LAPDs and 30 OPDs were compared after 1:1 propensity score matching. Demographic data, intraoperative and postoperative data (30 days), and pathological data were compared. Results: The study included a total of 93 patients, 30 underwent LAPD and 62 underwent OPD. After propensity score matching, the matched cohort included 30 patients in both groups. The LAPD presented several advantages over the OPD group, including a shorter incision length, reduced postoperative pain, earlier initiation of oral feeding, and shorter hospital stays. LAPD was not found to be inferior to OPD in terms of pancreatic fistula incidence (Grade B, 30.0% vs. 33.3%), achieving R0 resection (100% vs. 93.3%), and the number of lymph nodes harvested (12 vs. 14, p = 0.620). No significant differences in blood loss, short-term complications, pathological outcomes, readmissions, and early (30-day) mortality were observed between the two groups. Conclusions: LAPD has comparable safety, technical feasibility, and short-term oncological efficacy.

• Tribology and Lubricants
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• v.23 no.6
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• pp.266-271
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• 2007

The brake performance of sintered friction materials for the high speed train was studied. In this study, newly developed sintered materials based on copper were compared with the commercial products for high speed trains. They were tested on a 1/5 scale dynamometer using low carbon steel disks. Effectiveness, fade, and recovery tests were carried out to examine friction performance and the change of disk thickness variation (DTV) during brake applications and noise propensity were also evaluated. Results showed that the two sintered friction materials exhibit similar friction coefficients and braking performance, whereas the newly developed friction material was superior in terms of DTV generation and noise propensity to the commercial friction material. The improvement of the newly developed friction material was attributed to the high graphite content which reduced the stick-slip phenomena and prevented uneven disk wear by producing friction films on the counter disk.

• The Korean Journal of Health Service Management
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• v.11 no.3
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• pp.65-78
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• 2017

Objectives : Obesity is a worldwide health concern due to an increasing obese population. This study proposed to analyze the differences in medical costs and care utilization between obese and normal group using propensity score matching. Methods : Data were collected from the sample cohort database by the Korea National Health Insurance Corporation. Propensity score matching(PSM) was applied to control selection bias, and factors affecting obesity were used as covariates in PSM. Results : The results showed higher medical costs and care utilization in the obese group than the normal group. According to gender and medical type, there were differences in the relationships between obesity and medical charges and utilization. In particular, the differences in the female population were larger in both outpatients and inpatients than the male population. Conclusions : It is important to manage obesity, because obesity has a negative effect on national health insurance costs. These findings suggest directions for future research.

• Journal of the Korean Home Economics Association
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• v.39 no.9
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• pp.153-174
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• 2001

The objectives of this study were to examine the propensity and to analyze some determinants of complaining behavior about the educational services of private institutes. The survey was conducted by means of self-administered questionnaire with 546 university students Living in Seoul and Cheongjoo. They had an experience of studying in the educational services of private institutes in recent two years. Major findings were as following: (1) The propensity of private complaining behavior about the educational services of private institutes averages 3.36 points out of 5. This score is beyond the middle slightly. Whereas the propensity of pubic complaining behavior is very low. (2) According to the discriminant analysis, tuition fee, information supplied for solving the dissatisfaction, and altitude about the complaining behavior are the determinants to distinguish between complaining/non complains behavior group of private complaining behavior. (3) Information supplied for solving the dissatisfaction, kindness of the stars, the establishment, the way of making tuition fees, the degree of awareness of cost, the attitude about complaining behavior, the confidence of success for complaining behavior are the determinants to distinguish between complaining/non complains behavior group of public complaining behavior.