• Journal of Gastric Cancer
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• v.1 no.3
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• pp.168-173
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• 2001

Purpose: A positive esophageal margin is encountered in a total gastrectomy not infrequently. The aim of this retrospective review was to evaluate whether a positive esophageal margin predisposes a patient to loco-regional recurrence and whether it has an independent impact on long-term survival. Materials and Methods: A retrospective review of 224 total gastrectomies for adenocarcinomas was undertaken. The Chisquare test was used to determine the statistical significance of differences, and the Kaplan-Meier method was used to calculate survival rates. Significant differences in the survival rates were assessed using the log-rank test, and independent prognostic significance was evaluated using the Cox regression method. Results: The prevalence of esophageal margin involvement was $3.6\%$ (8/224). Univariate analysis showed that advanced stage (stage III/IV), tumor size ($\geq$5 cm), tumor site (whole or upper one-third of the stomach), macroscopic type (Borrmann type 4), esophageal invasion, esophageal margin involvement, lymphatic invasion, and venous invasion affected survival. Multivariate analysis demonstrated that TNM stage, venous invasion, and esophageal margin involvement were the only significant factors influencing the prognosis. All patients with a positive esophageal margin died with metastasis before local recurrence became a problem. A macroscopic proximal distance of more than 6 cm of esophagus was needed to be free of tumors, excluding one exceptional case which involved 15 cm of esophagus. Conclusion: All of the patients with a positive proximal resection margin after a total gastrectomy had advanced disease with a poor prognosis, but they were not predisposed to anastomotic recurrence. Early detection and extended, but reasonable, surgical resection of curable lesions are mandatory to improve the prognosis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.1107-1110
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• 2013

Intrahepatic cholangiocarcinoma (ICC), one of the primary liver cancers, is frequent in the northeastern part of Thailand. Surgical resection remains the best method of treatment, but patients suffering from ICC usually present at a late stage of the disease. Studies of survival and prognostic factors after surgery remain rare. The aim here was to evaluate the survival rate and factors affecting the survival of patients with intrahepatic cholangiocarcinoma after surgery. The study used a retrospective cohort design. The subjects were 73 consecutive patients with ICC, who were admitted for surgery to Srinagarind Hospital, Khon Kaen University, during the period 2005-2009. The censoring date was 31 December, 2011, data being evaluated using uni- and multivariate analyses. Postoperative survival analysis was performed by the Kaplan-Meier method, and the Cox proportional hazard model was used to identify independent prognostic factors. The total follow-up time was 99 person-years. The total number of deaths was 59, giving a mortality rate of 59 per 100 person-years. The cumulative 1-, 3-, and 5-year survival rates were 52.1%, 21.7%, and 11.2%, respectively. The median duration of survival after resection was 12.4 months. Univariate analysis revealed stage of disease, lymph node metastasis, histological type, histological grade and macroscopic classification to be statistically significant (p-value<0.05) prognostic factors. In the multivariate analysis, only macroscopic classification was statistically significant (p-value<0.05). In conclusion, macroscopic classification was the only independent factor found to be significantly associated with survival following surgical treatment of ICC.

• Journal of the Korean Institute of Gas
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• v.23 no.4
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• pp.19-27
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• 2019

The consumption of liquefied natural gas (LNG) has increased annually due to the strengthening of international environmental regulations. In order to produce stable and efficient LNG, it is essential to divide the global (overall) operating condition and construct a quick and accurate monitoring system for each operation condition. In this study, multi-mode monitoring system is proposed to the LNG plant fractionation process. First, global normal operation data is divided to local (subdivide) normal operation data using global principal component analysis (PCA) and k-means clustering method. And then, the data to be analyzed were matched with the local normal mode. Finally, it is determined the state of process abnormality through the local PCA. The proposed method is applied to 45 fault case and it proved to be more than 5~10% efficient compared to the global PCA and univariate monitoring.

• Earthquakes and Structures
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• v.23 no.3
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• pp.259-269
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• 2022

In this study, we introduce a canonical correlation analysis method to accurately assess the tunnel damage potential of ground motion. The proposed method can retain information relating to the initial variables. A total of 100 ground motion records are used as seismic inputs to analyze the dynamic response of three different profiles of tunnels under deep and shallow burial conditions. Nine commonly used ground motion parameters were selected to form the canonical variables of ground motion parameters (GMP_CCA). Five structural dynamic response parameters were selected to form canonical variables of structural dynamic response parameters (DRP_CCA). Canonical correlation analysis is used to maximize the correlation coefficients between GMP_CCA and DRP_CCA to obtain multivariate ground motion parameters that can be used to comprehensively assess the tunnel damage potential. The results indicate that the multivariate ground motion parameters used in this study exhibit good stability, making them suitable for evaluating the tunnel damage potential induced by ground motion. Among the nine selected ground motion parameters, peck ground acceleration (PGA), peck ground velocity (PGV), root-mean-square acceleration (RMSA), and spectral acceleration (Sa) have the highest contribution rates to GMP_CCA and DRP_CCA and the highest importance in assessing the tunnel damage potential. In contrast to univariate ground motion parameters, multivariate ground motion parameters exhibit a higher correlation with tunnel dynamic response parameters and enable accurate assessment of tunnel damage potential.

• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.703-711
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• 2018

Water distribution system (WDS) pipe bursts are caused from excessive pressure, pipe aging, and ground shift from temperature change and earthquake. Prompt detection of and response to the failure event help prevent large-scale service interruption and catastrophic sinkhole generation. To that end, this study proposes a improved Western Electric Company (WECO) method to improve the detection effectiveness and efficiency of the original WECO method. The original WECO method is an univariate Statistical Process Control (SPC) technique used for identifying any non-random patterns in system output data. The improved WECO method multiples a threshold modifier (w) to each threshold of WECO sub-rules in order to control the sensitivity of anomaly detection in a water distribution network of interest. The Austin network was used to demonstrated the proposed method in which normal random and abnormal pipe flow data were generated. The best w value was identified from a sensitivity analysis, and the impact of measurement frequency (dt = 5, 10, 15 min etc.) was also investigated. The proposed method was compared to the original WECO method with respect to detection probability, false alarm rate, and averaged detection time. Finally, this study provides a set of guidelines on the use of the WECO method for real-life WDS pipe burst detection.

• Journal of Gastric Cancer
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• v.5 no.4 s.20
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• pp.281-287
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• 2005

Purpose: This study was conducted to evaluate the effectiveness and the role of post-operative adjuvant chemoradiation therapy in a stage-II (UICC, 1997) primary gastric cancer. Materials and Methods: From September 1994 to December 2004, 954 stage-II gastric-cancer patients were seen, and all of them underwent a curative resection with extensive (D2) lymph-node dissection. The chemotherapy consisted of fluorouracil $(400mg/m^2)$ plus leucovorin $(20mg/m^2)$ for 5 days, followed by 4,500 cGy of radiotherapy for 5 weeks with fluorourcil and leucovorin on the first 4 days and the last 3 days of radiotherapy. Two five-day cycles of chemotherapy were given four weeks after the completion of radiotherapy. The Kaplan-Meier method was used to estimate the survival rates. To assess the importance of potential prognostic factors, we performed univariate and multivariate analyses using a log-rank test and Cox's proportional hazards regression model. A P value <0.05 was considered significant. Results: Univariate analysis revealed that age, tumor size, gross type, surgical method, and postoperative adjuvant therapy had statistical significance. Among these factors, age, surgical method, tumor size, surgical method, and postoperative adjuvant therapy were found to be independent prognostic factors by using a multivariate analysis. The postoperative adjuvant chemotherapy group and the chemoradiation therapy group had survival benefit compared to the surgery-only group. However the chemoradiation therapy group had no significant survival benefit compared to the chemotherapy group. Conclusion: The postoperative adjuvant therapy in stage-II gastric-cancer patients had significant benefit. Therefore, postoperative adjuvant chemoradiation therapy has an acceptable effect. A large-scale, randomized study is needed to evaluate the effectiveness and the role of postoperative radiation therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.199-203
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• 2012

Purpose: To evaluate the prognostic value of serum CYFRA21-1, CEA and hemoglobin levels regarding long-term survival of patients with esophageal squamous cell carcinoma (ESCC) treated with concurrent chemoradiotherapy (CRT). Methods: Age, gender, Karnofsky Performance Status (KPS), tumor location, tumor length, T stage, N stage and serum hemoglobin, and CYFRA21-1 and CEA levels before concurrent CRT were retrospectively investigated and related to outcome in 113 patients receiving 5-fluorouracil and cisplatin combined with radiotherapy for ESCC. The Kaplan-Meier method was used to analyze prognosis, the log-rank to compare groups, the Cox proportional hazards model for multivariate analysis, and ROC curve analysis for assessment of predictive performance of biologic markers. Results: The median survival time was 20.1 months and the 1-, 2-, 3-, 5- year overall survival rates were 66.4%, 43.4%, 31.9% and 15.0%, respectively. Univariate analysis showed that factors associated with prognosis were KPS, tumor length, T-stage, N-stage, hemoglobin, CYFRA21-1 and CEA level. Multivariate analysis showed T-stage, N-stage, hemoglobin, CYFRA21-1 and CEA level were independent predictors of prognosis. By ROC curve, CYFRA21-1 and hemoglobin showed better predictive performance for OS than CEA (AUC= 0.791, 0.704, 0.545; P=0.000, 0.000, 0.409). Conclusions: Of all clinicopathological and molecular factors, T stage, N stage, hemoglobin, CYFRA21-1 and CEA level were independent predictors of prognosis for patients with ESCC treated with concurrent CRT. Among biomarkers, CYFRA21-1 and hemoglobin may have a better predictive potential than CEA for long-term outcomes.

• Journal of Korean Clinical Health Science
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• v.1 no.3
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• pp.39-48
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• 2013

Purpose. This study was performed on survey related dental hygienist job stress and job satisfaction, to improve the work efficiency of the dental hygienist and for dental hygienist to eliminate the cause of stress for health promotion and for management to be able to help to finding ways to provide basic data. Method. This survey is based on 235 people who are dental hygienists working in Changwon city from November 1 to November 30 2012, by statistical analysis of collected data using SPSS Win Program 20.0 version t-test, univariate analysis of variance (one-way ANOVA), correlation analysis that performed to determine statistical significance with a significance level of 0.05 was considered. Results. For correlation of job satisfaction and job stress, the job demands, job insecurity, and workplace culture shows a negative correlation. For Correlation of the physical environment, insufficient job control, interpersonal conflict, and organizational system is, lack of reward shows a positive correlation. The less job stress due to Insufficient job control, interpersonal conflict, organizational system, is, the higher job satisfaction due to job demands and workplace culture is.(p <0.05), The higher job stress is, the higher the job satisfaction is(p <0.05). Conclusions. Job satisfaction and job stress may be relevant each other, there fore several measures should be sought to solve insufficient job control, interpersonal conflict, organizational system and the lack of reward, consequently to increase the job satisfaction of dental hygienists.

• Journal of Chest Surgery
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• v.26 no.4
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• pp.249-254
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• 1993

Atrial fibrillation is commonly associated with organic mitral valve disease including rheumatic valvular heart diasease or mitral valve prolapse and so forth. Although spontaneous sinus reversion may occur in some patients after mitral valve operation, recurrence of atrial fibrillation is the rule in most of these patients. We have tried to maintain sinus rhythm after mital valve operation with oral quinidine therapy, and we will show the efficacy of this therapy in this report. From January 1986 to August 1992, 60 patients of mitral valvular heart disease, who had had atrial fibrillation preoperatively and gained sinus rhythm postoperatively, were selected for this study. These patients were divided into 2 groups: Control group [n=30] and Quinidine trial group [n=30]. The age,sex, duration of symptoms,left atrial size and other risk factors of the reversion to atrial fibrillation were adjusted to be similar between the two groups. The maintenance rate of sinus rhythm was calculated by Kaplan-Meier method, and the rate was significantly higher in quinidine trial group than in control group [ p=0.0001 ]. Univariate analysis was performed on the risk factors of reversion to atrial fibrillation, and the difference of maintenance rate between the two groups were corrected with this result: the difference was still statistically significant [ p=0.0205 ]. The quinidine levels were measured in postoperative days, and there were no difference of serum quinidine level between the quinidine success group and quinidine failure group. In conslusion, oral quinidine therapy was effective for the maintenance of sinus rhythm after mitral valve operation compared to control group, and there was no correlation between the serum quinidine level and clinical efficacy of quinidine therpy.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.4102-4102
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• 2001

In multivariate analysis, absorbance spectrum is measured over a band of wavelengths. One does not often pay attention to the size of this wavelength band. However, it is desirable that spectrum is measured at only necessary wavelengths as long as the acceptable accuracy of prediction can be met. In this paper, the method of selecting an optimal band of wavelengths based on the loading vector analysis was proposed and applied for determining total protein in human serum using near-infrared transmission spectroscopy and PLSR. Loading vectors in the full spectrum PLSR were used as reference in selecting wavelengths, but only the first loading vector was used since it explains the spectrum best. Absorbance spectra of sera from 97 outpatients were measured at 1530∼1850 nm with an interval of 2 nm. Total protein concentrations of sera were ranged from 5.1 to 7.7 g/㎗. Spectra were measured by Cary 5E spectrophotometer (Varian, Australia). Serum in the 5 mm-pathlength cuvette was put in the sample beam and air in the reference beam. Full spectrum PLSR was applied to determine total protein from sera. Next, the wavelength region of 1672∼1754 nm was selected based on the first loading vector analysis. Standard Error of Cross Validation (SECV) of full spectrum (1530∼l850 nm) PLSR and selected wavelength PLSR (1672∼1754 nm) was respectively 0.28 and 0.27 g/㎗. The prediction accuracy between the two bands was equal. Wavelength selection based on loading vector in PLSR seemed to be simple and robust in comparison to other methods based on correlation plot, regression vector and genetic algorithm. As a reference of wavelength selection for PLSR, the loading vector has the advantage over the correlation plot since the former is based on multivariate model whereas the latter, on univariate model. Wavelength selection by the first loading vector analysis requires shorter computation time than that by genetic algorithm and needs not smoothing.