• Steel and Composite Structures
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• v.49 no.1
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• pp.1-17
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• 2023

Based on Ahmadzadeh-Varvani hardening rule (A-V model), multiaxial ratcheting effect of Z2CND18.12N austenitic stainless steel is simulated by ABAQUS with user subroutine UMAT. The results show that the predicted results of the origin multiaxial A-V model are lower than the experimental data, and it is difficult to control ratcheting strain rate. In order to improve the predicted capability of A-V model, the A-V model is modified. In this study. Moreover, under the assumption of the von Mises yield criterion and normal plasticity flow rule, we develop a numerical algorithm of plastic strain with the improved model to implement the finite element calculation of the model. Internal iteration in the numerical algorithm was implemented with the Euler backward method, which calculated the trial strain for each equilibrium iteration using the consistent tangent matrix. With a user subroutine, the proposed model is programmed into ABAQUS for a user - executable version. By simulating the uniaxial ratcheting of a round bar made of Z2CND18.12N austenitic stainless steel, we observe that the predicted results simulated by ABAQUS with UMAT are compared with the experimental data. The predicted results of the improved multiaxial A-V model are consistent well with the experimental data.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1491-1496
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• 2009

Stroke is usually associated with the cerebral blood flow of the central nervous system. However, studies concerning the effects of neurologic sysmptoms induced from stroke on the peripheral blood flow has not taken place sufficiently. To ascertain the feasibility of a blood flow meter adopting to use doppler ultrasonogrphy, under the prospect that hemiparesis induced from stroke may have effect on the peripheral blood flow, the peripheral blood flow velocity was observed. The control group made up of healthy people without any factors capable of effecting the peripheral blood flow velocity, and patient group which consist of hemiparetic people induced from stroke, were recruited. Volumes of recruitment are 21 persons in the patient group, and 29 persons in the control group, but the final numbers of people are 17 and 21 respectively because of the inconsistancy in the method of the test. The non-invasive method of Doppler effect of Ultrasound was used to measure the blood flow velocity. The blood flow velocity in the peripheral part of left and right fourth fingers:dorsal branches of proper palmar digital artery to dorsum of distal phalanges, was measured in the control group and patient group through Doppler Ultrasound. In comparison of the control group and the patient group, the systolic blood flow velocity from the peripheral part of the upper extremity was lower in the patient group than that of the control group. According to such results, it is concluded that hemiparesis induces the reduction of the peripheral blood flow velocity in the systolic phase.

• The Korean Journal of Nuclear Medicine
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• v.15 no.2
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• pp.11-17
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• 1981

Cholescintigraphic studies with $^{99m}Tc-HIDA$(dimethyl iminodiacetic acid) were performed in 22 cases of normal subjects, 21 of acute cholecystitis, 12 of chronic cholecystitis and 12 others, with the results of, 1) In normal control group, liver and intrahepatic biliary tree, CBD and gall bladder, and G-I tract appeared at 10, 20 and 30 minutes after intravenous injection of $^{99m}Tc-HIDA$ respectively, 2) In acute cholecystitis, 20 among 21 cases showed non-visualization of gall bladder with the diagnostic accuracy, sensitivity and specificity of 93.2%, 95.2% and 100% respectively. 3) In chronic cholecystitis, 5 among 12 cases showed non-visualization of gall bladder and remained 7 among 12 cases showed poor contraction of gall bladder (4), delayed visualization of gall bladder (1) and normal findings (2). 4) In the other disease group, the 12 cases which initially suspected as acute cholecystitis, revealed normal scan findings to exclude the cystic duct obstruction easily, With the above results, this scintigraphic procedure was found very rapid, accurate and easily available method for the determining of the cystic duct patency.

• The Journal of Internal Korean Medicine
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• v.38 no.3
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• pp.367-375
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• 2017

Objective: To investigate the effect of Artemisiae Iwayomogii Herba, Curcumae Radix, and Aurantii Fructus Immaturus complex extract (ACA) on dyslipidemia-related factor expression and anti-oxidation in HepG2 cells. Method: After treatment with ACA in the HepG2 cells, DPPH, ABTS radical scavenging activity, ROS production, and glutathione (GSH) production were measured. The free fatty acid, lipid peroxidation (MDA), ACAT1, and HMG-CoA reductase mRNA expression were measured in the HepG2 cells after treatment with ACA. Results: 1. DPPH, ABTS radical scavenging activity increased in an ACA concentration-dependent manner. 2. ACA significantly decreased ROS production in comparison to the control group. 3. ACA significantly increased glutathione production. 4. ACA significantly decreased free fatty acid and lipid peroxidation (MDA) in the HepG2 cells. 5. ACA decreased the mRNA expression of ACAT1 and HMG-CoA reductase. Conclusion: These results suggest that Artemisiae Iwayomogii Herba, Curcumae Radix, and Aurantii Fructus Immaturus complex extract (ACA) inhibits dyslipidemia-related factor expression and that it is effective in anti-oxidation. A future in vivo experiment with ACA is needed to investigate the effect on anti-dyslipidemia. It is expected that ACA is effective in anti-dyslipidemia and applied to cardiovascular disease, ischemic heart disease, stroke, etc.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.158-166
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• 2004

Background & Object : The aim of this study was to investigate the usefulness of electrogastrography in the diagnosis field of traditional medicine through a study of the relationship between gastric motility and health condition based on oriental medicine diagnostic theory in functional dyspepsia. Method : 86 patients (male 27, female 59) with functional dyspepsia and 10 healthy control subjects (male 5, female 5) were involved in the investigation. The disease information of functional dyspepsia (based on Rome criteria II) was used for dyspeptic index and scores were obtained from the comprehensive diagnosis of Qui, Xue, Shui was applied as index for health condition, those were all investigated by questionnaire. Gastric motility were recorded and analyzed using electrogastrography in fasting and postprandial period. Results : The total score of comprehensive diagnosis of Qui Xue Shui was influenced by the number of functional dyspepsia symptoms (p=0.026). In terms of electrogastrographical parameters, both postpranial normal slow waves regularity(p=0.003) and power ratio (p=0.001) in the patients had the statistical significance and they showed an incremental inverse correlation with the number of symptoms. Dominant frequency and fasting normal slow waves regularity ratio had no statistical significance. Conclusion : Results suggest that electrogastrography is useful in evaluating the health condition of patient by comprehensive diagnosis of Qui Xue Sui.

• Gut and Liver
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• v.12 no.6
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• pp.728-735
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• 2018

Background/Aims: The combination of nab-paclitaxel and gemcitabine (nab-P/Gem) is widely used for treating metastatic pancreatic cancer (MPC). We aimed to evaluate the therapeutic outcomes and prognostic role of treatment-related peripheral neuropathy in patients with MPC treated with nab-P/Gem in clinical practice. Methods: MPC patients treated with nab-P/Gem as the first-line chemotherapy were included. All 88 Korean patients underwent at least two cycles of nab-P/Gem combination chemotherapy (125 and $1,000mg/m^2$, respectively). Treatment-related adverse events were monitored through periodic follow-ups. Overall survival and progression-free survival were estimated by the Kaplan-Meier method, and the Cox proportional hazards regression linear model was applied to assess prognostic factors. To evaluate the prognostic value of treatment-related peripheral neuropathy, the landmark point analysis was used. Results: Patients underwent a mean of $6.7{\pm}4.2$ cycles during $6.3{\pm}4.4$ months. The median overall survival and progression-free survival rates were 14.2 months (95% confidence interval [CI], 11.8 to 20.3 months) and 8.4 months (95% CI, 7.1 to 13.2 months), respectively. The disease control rate was 84.1%; a partial response and stable disease were achieved in 30 (34.1%) and 44 (50.0%) patients, respectively. Treatment-related peripheral neuropathy developed in 52 patients (59.1%), and 13 (14.8%) and 16 (18.2%) patients experienced grades 2 and 3 neuropathy, respectively. In the landmark model, at 6 months, treatment-related peripheral neuropathy did not have a significant correlation with survival (p=0.089). Conclusions: Nab-P/Gem is a reasonable choice for treating MPC, as it shows a considerable disease control rate while the treatment-related peripheral neuropathy was tolerable. The prognostic role of treatment-related neuropathy was limited.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.1
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• pp.42-48
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• 2006

Open reduction and rigid internal fixation is the most popular treatment method for maxillofacial fracture patients, and it is unevitable that postoperative pain can be developed. Many surgeons including oral & maxillofacial surgeons have made constant efforts to decrease postoperative pain. This study is a comparison of postoperative analgesia and intramuscular analgesia in patients with mandibular fractures. In this study, twenty-one patients (Experimental group) were randomly selected and they were injected with IV patient-controlled analgesia (PCA; Walkmed$^{(R)}$, USA). For control group another twenty-one patients were injected with intramusclar non-steroid anti-inflammatory drugs (Rheoma$^{(R)}$, Samsung Pharm. Co.). And then, we measured visual analogue scale (VAS) scores from first postoperative day to second day at regular time interval. The following results were uptained; 1. In patient group who with open reduction and rigid internal fixation, there was significant difference of postoperative analgesic effect during the first postoperative day(p<0.05). 2. In patient group with over 90 minutes surgery time, there was significant difference of postoperative analgesic effect during the first and second postoperative day when compared between experimental group and control group(p<0.05). 3. In patient group with less than 90 minutes surgery time, there was no significant difference of postoperative analgesic effect during the first and second postoperative day when compared between experimental group and control group(p>0.05). 4. In patient group with surgery of open reduction using rigid internal fixation at single fractured site, there was no significant difference of postoperative analgesic effect during the first and second postoperative day when compared between experimental group and control group(p>0.05). 5. In patient group with surgery at two fractured sites, there was significant difference of postoperative analgesic effect during the first postoperative day when compared between experimental group and control group(p<0.05). As mentioned above, it suggest that patient-controlled analgesia is more effective for postoperative pain relief than intramuscular injection in patients with rigid internal fixation by open reduction after mandibular fracture occurred. Especially, it is considered that in patient with more than 90 minutes surgery time or in cases with multiple fractured sites had more effective results with PCA therapy than conventional intramuscular analgesics.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.178-187
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• 2007

One important issue in power systems is dynamic instability due to loosing balance relation between electrical generation and a varying load demand that justifies the necessity of stabilization. Moreover, Power System Stabilizer (PSS) must have capability of producing appropriate stabilizing signals over a wide range of operating conditions and disturbances. To overcome these drawbacks, this paper proposes a new method for robust design of PSS by using an auto-tuning fuzzy control in combination with Real-Coded Genetic Algorithm (RCGA). This method includes two fuzzy controllers; internal fuzzy controller and supervisor fuzzy controller. The supervisor controller tunes the internal one by on-line applying of nonlinear scaling factors to inputs and outputs. The RCGA-based method is used for off-line training of this supervisor controller. The proposed PSS is tested in three operational conditions; nominal load, heavy load, and in the case of fault occurrence in transmission line. The simulation results are provided to compare the proposed PSS with conventional fuzzy PSS and conventional PSS. By evaluating the simulation results, it is shown that the performance and robustness of proposed PSS in different operating conditions is more acceptable

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.590-599
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• 1996

Background : Bronchial artery embolization has been established as an effective means to control hemoptysis, especially in patients with decreased pulmonary function and those with advanced chronic obstructive pulmonary disease. We evaluated the effect of arterial embolization in immediate control of massive hemoptysis and investigated the clinical and angiographic characteristics and the course of patients with reccurrent hemoptysis after initial succeseful embolization. Another purpose of this study was to find predictive that cause rebleeding after bronchial artery embolization. Method : We reviewed 47 cases that underwent bronchial artery embolization for the management of massive hemoptysis, retrospectively. We analyzed angiographic findings in all cases before bronchial artery embolization and also reviewed the angiographic findings of patients that underwent additional bronchial artery embolization for the control of reccurrent hemoptysis to find the clauses of rebleeding. Results : 1) Underlying causes of hemoptysis were pulmonary tuberculosis(n=35), bronchiectasis(n=5), aspergilloma(n=2), lung cancer(n=2), pulmonary A-V malformation(n=1), and unknown cases(n=2). 2) Overal immediate success rate was 94%(n=44), an6 recurrence rate was 40%(n=19). 3) The prognostic factors such as bilaterality, systemic-pulmonary artery shunt, multiple feeding arteries and degree of neovascularity were not statistically correlated with rebleeding tendency (p value>0.05). 4) At additional bronchial artery embolization, Revealed recannalization of previous embolized arteries were 14/18cases(78%) and the presence of new deeding arteries was 8/18cases(44%). 5) The complications(31cases, 66%) such as fever, chest pain, cough, voiding difficulty, paralytic ileus, motor and sensory change of lower extremity, atelectasis and splenic infarction were occured. Conclusion : Recannalization of previous embolized arteries is the major cause of recurrence after bronchial artery embolization. Despite high recurrence rate of hemoptysis, bronchial artery embolization for management of massive hemoptysis is a effective and saute procedure in immediate bleeding control.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.14-19
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• 2004

This paper presents two approaches for designing a digital controller of UPS inverter with time response requirements and a fixed sampling time, which are inward and outward approaches based on a double loop feedback structure. In both approaches, the emulation method. is occupied. Thus we first design continuous-time controllers and then obtain digital controllers by using discretization. We apply the characteristic ratio assignment (CRA) in order to achieve the time response specifications. Also, the internal model control has been used for compensating phase delay in outward approach. The performances of the proposed controller are evaluated through several simulations carried out with Simpower system toolbox 3.0 of $Simulink^{(R)}$.