• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.355-359
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• 2001

This paper presents an implementation of digital control system of speed sensorless for Reluctance Synchronous Motor (RSM) drives with DTC. The control system consists of stator flux observer, rotor position/speed/torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source inverter, and TMS320C31 DSP controller by using fully integrated control software. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control that inputs are current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor position is estimated by observed stator flux-linkage space vector. The estimated rotor speed is determined by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operating area. It does not require the knowledge of any motor parameters, nor particular care for motor starting, In order to prove the suggested control algorithm, we have a simulation and testing at actual experimental system. The developed sensorless control system is shown a good speed control response characteristic results and high performance features in 50/1000 rpm with 1.0Kw RSM having 2.57 ratio of d/q reluctance.

• Journal of Power Electronics
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• v.2 no.2
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• pp.146-153
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• 2002

this paper presents an implementation of digital control system of speed sensorless for Reluctance Synchronous Motor (RSM) drives with direct torque control (DTC). The problem of DTC for high-dynamic performance RSM drive is generating a nonlinear torque due to a saturated nonlinear inductance curve with various load currents. The control system consists of stator flux observer, compensating inductance look-up table, rotor position/speed/torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source unverter, and TMS320C31 DSP controller. The stator flux observer is based on the combined voltage and current model with stator flux feedback adapitve control that inputs are the compensated inductances, current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor position is estimated rotor speed is determined by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operation area. It does not requrie the knowledge of any montor paramenters, nor particular care for moter starting, In order to prove the suggested control algorithm, we have simulation and testing at actual experimental system. The developed sensorless control system is showing a good speed control response characterisitic result and high performance features in 20/1500 rpm with 1.0Kw RSM having 2.57 ratio of d/q reluctance.

• Journal of Hospice and Palliative Care
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• v.7 no.1
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• pp.49-63
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• 2004

Purpose: The Hospice Oriented Medical Record (HOMR) was developed for assessing the pain and symptoms of terminal cancer patients. Methods and Results: The HOMR consists of an instruction for users and 2 assessment pages which include the graph showing vital signs (temperature, blood pressure, pulse, respiration rate and pain score), current problem lists, performance status, laboratory data, pain characteristics and management, sedation score, associated symptoms and drug side effects, etc. Pilot study was performed in the inpatient Hospice Care Unit in Guro Hospital, Korea University Medical Center. Because an one-week progress data was recorded in HOMR as a flow sheet, the patient's condition and pain control status could be seen at a glance. Conclusion: The HOMR is useful for assessing the terminal cancer patients because it is simple and convenient to use. Further research is needed before it can be universally used in the clinical settings.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4251-4254
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• 2014

Background: Treatment of anemia is an important issue in the palliative care setting. Blood transfusion is generally used for this purpose in supportive care. However the place of blood transfusion in terminally ill cancer cases is less far established. Objective: We aimed to outline the use of transfusions and to find the impact of blood transfusion on survival in patients with advanced cancer and very near to death. Design: Patients dying in 2010-2011 with advanced cancer were included in the study. We retrospectively collected the data including age, type of cancer, the duration of last hospitalisation, ECOG performance status, Hb levels, transfusion history of erythrocytes and platelets, cause and the amount of transfusion. The anaemic patients who had transfusion at admission were compared with the group who were not transfused. Survival was defined as the time between the admission of last hospitalisation period and death. Results: Three hundred and ninety eight people with solid tumours died in 2010-2011 in our clinic. Ninety percent of the patients had anemia at the time of last hospitalisation. One hundred fifty three patients had erythrocyte transfusion at admission during the last hospitalisation period (38.4%). In the anaemic population the duration of last hospitalisation was longer in patients who had erythrocyte transfusion (15 days vs 8 days, p<0.001). Conclusions: Patients who had blood transfusion at the end of life lived significantly longer than the anaemic patients who were not transfused. This study remarks that blood transfusions should not be withheld from terminal cancer patients in palliative care.

• Journal of Hospice and Palliative Care
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• v.7 no.2
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• pp.214-220
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• 2004

Purpose: As for the malignant bowel obstruction of terminal cancer patient, a prognosis is relatively bad. Physicians consider palliative procedures or surgery for the quality of life, but sometimes it is hard to decide. After diagnosis of a malignant bowel obstruction in terminal cancer patients, we investigated the clinical characteristics, the prognostic factors and the survival of patients with palliative procedures or surgery. Methods: we retrospectively reviewed the medical records in 40 malignant bowel obstruction patients who had been diagnosed as terminal cancer from May in 2002 to May in 2004. Results: There were 21 males (53%) and 19 females (47%), and median age of patients was $64.1{\pm}1.58$ years. The most common cause of malignant bowel obstruction was colorectal cancer (18 patients, 45%), followed by stomach cancer (11, 28%), pancreatic cancer (4, 10%), others (7, 19%). Metastases were carcinomatosis peritonei (14 patients, 35%), liver (13, 33%). During a bowel obstruction, symptoms were vomiting (15 patients, 38%), abdominal pain (10, 25%), constipation (6, 15%), abdominal distension (5, 13%). Performance status (ECOG) was 2 score (16 patients, 40%), 3 score (20, 50%), 4 score (4, 10%). Palliative procedure group were 30 patients, the others 10. Median survival in palliative procedure group was 142 days, that of no palliation group 30. Median survival time of palliative procedure group from palliative procedures or surgery were significantly higher than that of no palliation group from diagnosis of malignant bowel obstruction. Prognostic factors of palliative procedure group were PS, site of obstruction and primary cancer. Median survival in PS 2, lower GI obstruction and colorectal cancer was higher than PS 3, upper GI obstruction and others, respectively. Conclusion: we recommend aggressively palliative procedures or surgery in malignant bowel obstruction patients diagnosed with terminal cancer if palliative procedures or surgery could be performed effectively.

• Journal of Hospice and Palliative Care
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• v.22 no.4
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• pp.198-206
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• 2019

Purpose: The Act on Hospice and Palliative Care and Decisions on Life-sustaining Treatment for Patients at the End of Life was enacted in 2016 and has taken effect since 2018 February. The content of this act was based on Physician Orders for Life-Sustaining Treatment (POLST) in the United States and we modified it for terminal cancer patients registering hospice. The object of this study is to investigate preference and implementation rate for modified Korean POLST (MMK-POLST) items in hospice ward. Methods: From February 1, 2017 to April 30, 2019, medical records regarding MMK-POLST were retrospectively analyzed for all patients hospitalized in the hospice ward of Gyeongsang National University Hospital. Results: Of the eligible 387 total cohorts, 295 patients filled out MK-POLST. MK-POLST has been completed in 133 cases (44.1%) by the patient themselves, 84 cases (28.5%) by the spouse, and 75 cases (25.4%) by their children, respectively. While only 13 (4.4%) out of 295 MK-POLST completed patients refused the parenteral nutrition and 5 patients (1.7%) for palliative sedation, the absolute majority of 288 (97.6%) patients did not want cardiopulmonary resuscitation (CPR) and ventilators and 226 people (76.9%) for pressor medications. Kappa values for the matched strength of MK-POLST implementation were poor for all items except CPR, ventilators and palliative sedation. Conclusion: Hospice patients refused to conduct cardiopulmonary resuscitation, ventilators and pressor agents. In contrast, antibiotics, parenteral nutrition and palliative sedation were favored in the majority of patients.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.1
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• pp.69-78
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• 2017

As the smartphone-based devices are diffused and developed rapidly, they provide the convenience to the users. The abovementioned sentence technologies are being used not only in the existing sensor and wireless network technology but also in the application services of the diverse fields application services such as smart appliance, smart car, smart health care, etc. and the new fusion paradigm from the industry is presented by undertaking the researches in diverse area by the enterprises and research institutions. However, the smart environment exposes its weaknesses in the mobile terminal area, existing wireless network and IT security area. In addition, due to new and variant ways of attack, not only the critical information are disclosed However also the financial damages occur. This paper proposed the protocol to perform the smartphone-based safe device monitoring and safe communication. The proposed protocol designed the management procedure of registration, identification, communication protocol and device update management protocol and the safety against the attack techniques such as the an-in-the-middle-attack, impersonation attack, credential threat, information leaks and privacy invasion was analyzed. It was observed that the proposed protocol showed the performance improved by approximately 52% in the communication process than the existing system.

• Journal of Hospice and Palliative Care
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• v.19 no.4
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• pp.303-309
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• 2016

Purpose: Malignant ascites is a common complication in terminal cancer patients. Less-invasive pigtail catheter insertion is the most frequent procedure in patients who need repeated ascites drainage. This study investigated effects and adverse events associated with catheter insertion for ascites drainage and evaluated prognostic outcomes. Methods: We reviewed medical records between 2010 and 2013 of hospice and palliative care institutions in Seoul, South Korea. Among 2,608 inpatients, 67 patients received ascites pigtail catheter drainage. We reviewed demographic data, palliative performance scale, laboratory data, duration of catheter insertion, prevalence and type of complications, use and duration of antibiotics, and survival time. Univariate and multivariate Cox regression models were used to evaluate prognostic outcomes related with catheter insertion. Results: Ascites drainage was performed most commonly in hepatobiliary and gastric cancer patients. Ascites symptoms improved in 55 patients after the catheter drainage. Adverse events included pain (19.4%), leakage (14.9%), disconnection (7.5%), catheter occlusion (6%) and fever (4.5%). In Cox regression analysis, survival time from the catheter insertion was significantly associated with Palliative Performance Scale (PPS) (HR 0.73; P value 0.045) and serum sodium level (HR 2.77; P value 0.003) in a multivariate model. Conclusion: Patients' PPS and serum sodium level should be considered before making a decision of pigtail catheter insertion.

• Journal of Hospice and Palliative Care
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• v.19 no.1
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• pp.26-33
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• 2016

Purpose: This study was conducted to identify clinical characteristics of oncologic patients at a point when they signed their do-not-resuscitate (DNR) orders. Methods: From January through December 2014, we retrospectively analyzed the records of 197 patients who passed away after agreeing to a DNR order in the hemato-oncology department of a tertiary hospital. Results: Of all, 121 patients (61.4%) were male and 76 (38.6%) were female, and their average age was 58.7 years. Ninety-four patients (47.7%) had gastrointestinal cancer. The ECOG performance status at admission was grade 3 in 76 patients (36.5%) and grade 4 in 11 (5.6%). The patients' mean hospital stay was 20 days. The mean duration from the admission to DNR decision was 13 days, and the mean duration from DNR decision to death was seven days. Conclusion: Study results indicate that a decision on signing or refusing a DNR order was made by medical staff mostly based on the opinions of patients' guardians rather than the patients themselves. This suggests that patients' own wishes are not well respected. Thus, it is urgent to establish institutional devices to enhance cancer patients' autonomy regarding DNR and to define an adequate timing for withdrawal of treatments.

• Journal of Hospice and Palliative Care
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• v.11 no.4
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• pp.181-187
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• 2008

Purpose: In order to establish efficient palliative treatment plans. It is important to estimate the survival time of a terminally ill cancer patient as accurate as possible. Proper estimation of life expectancy aids not only in improving the quality of life of the patient, it also promotes productive communication between the medical staff and the patient. The aim of this study is to determine the efficacy of neutrophil-lymphocyte ratio as a predictor of survival time in terminally ill cancer patients. Methods: Between January 2004 and June 2007, 67 terminally ill cancer patients who were admitted or transferred for palliative care, were included. Patients were categorized into three groups by Neutrophil-Lymphocyte Ratio. Demographic characteristics, clinical characteristics and blood samples were analyzed. Results: In univariate analysis, survival time of the highest Neutrophil-Lymphocyte Ratio group (${\geq}12.5$) was significantly shorter than that of the others (hazard ratio (HR)=3.270, P=0.001). After adjustment for low performance status (ECOG score 4) and dyspnea, high Neutrophil-Lymphocyte Ratio (${\geq}12.5$) was significantly and independently associated with short survival time (HR=2.907, P=0.007). Neutrophil-Lymphocyte Ratio was also significantly increased before death (P=0.001). Conclusion: Neutrophil-Lymphocyte Ratio can be useful in predicting life expectancy in terminally ill cancer patients.