• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.1
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• pp.33-42
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• 2003

This paper deals with the FEM analysis of nonlinear sloshing of incompressible, invicid and irrotational flow in two dimensional rectangular tank. We use laplace equation based on potential theory as governing equation. For large amplitude sloshing motion, kinematic and dynamic free surface conditions derived from Bernoulli equation are applied. This problem is solved by FEM using 9-node elements. For the time integration and accurate velocity calculation, we introduce predictor-corrector time marching scheme and least square method. Also, numerical stability in tracking of free surface is obtained by direct calculation of free surface location to time variation. Numerical results of sloshing induced by harmonic excitations, while comparing with those of linear theory and references, prove the accuracy and stability. After verification of our program, we analyze sloshing response characteristics to the fluid height and the excitation amplitude.

• The Korean Journal of Pain
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• v.21 no.2
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• pp.164-167
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• 2008

Frozen shoulder is known to be a self-limited disease, and it is associated with chronic pain and limitation of joint movement. Although its etiology is still unknown, frozen shoulder is associated with several diseases. The diagnosis is made based on the medical history, the clinical and radiological examinations and exclusion of other shoulder pathologies. The skeleton is one of the most common sites of metastasis in patients with lung cancer. It has been reported that the incidence of bone metastases in lung cancer patients is approximately 30-40%, and the median survival time of patients with such metastases is 6-7 months. We experienced a case of a 77-year-old female patient who complained of right shoulder pain and limited joint mobility, and these symptoms were due to metastatic lung cancer in the shoulder.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.1
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• pp.55-63
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• 2022

A stranded ship means a ship which is stuck on a rock or a seabed, and cannot move by itself. The lightening plan is required to refloat the stranded ship. For this, we have to understand the forces and moments acting on the ship, which is composed of the gravity, buoyancy, and reaction force due to the touched area below the ship. This study defines those forces and moments, and proposed the calculation method to find the posture based on the static equilibrium. It is divided by two steps. In the first step, the magnitude and position of the reaction force are obtained based on the known information such as initial trim angle and draft of the ship. In the second step, the reaction force and the posture is calculated due to the three cases such as addition, reduction, and movement of the cargo. It is applied to three examples in order to calculate the reaction force, and the trim angle due to changes of the cargo. As a results, we successfully obtain the magnitudes and positions of forces acting on the stranded ship and to check the posture of the stranded ship.

• Composites Research
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• v.27 no.5
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• pp.190-195
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• 2014

This paper predicts the complex permittivity of MWNT added epoxy depending on agglomeration by numerical analysis. 1wt% MWNT added epoxy specimen is prepared using 3-roll-mill method and its complex permittivity is measured in X-band (8.2~12.4 GHz) using freespace measurement system. The analytic model is comprised of cube epoxy and perfect sphere agglomeration. The complex permittivity of the agglomeration model is predicted by complex permittivity mixing rule using the measured complex permittivity of epoxy and 1 wt% MWNT added epoxy. Commercial electromagnetic analysis software, CST, is used to obtain S-parameter of the analytic model and MATLAB code is used to calculate complex permittivity from the S-parameter. It is confirmed that the complex permittivity increases when the agglomeration size decreases.

• Radiation Oncology Journal
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• v.24 no.2
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• pp.103-109
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• 2006

Purpose: To evaluate the treatment outcome according to the salvage treatment modalities and identify the prognostic factors influencing the survival. Materials and Methods: Forty-five patients with locally recurrent rectal cancer treated between 1994 to 2003 were reviewed retrospectively. Median time from initial surgery to loal recurrence was 16months. Of the patients, 25 (56%) recurred at presacral and perirectal space. Among the 18 (40%) patients who received salvage surgery, 14 patients were treated with postoperative chemoradiotherapy. Among 27 (60%) patients who didn't receive salvage surgery, 16 were treated with chemoradiotherapy and 11 were treated with radiotherapy alone. Radiotherapy was given with total dose ranging from 37.5 to 64.8 Gy. Results: Five-year locoregional progression-free survival rate and overall survival rate of all patents were 49.5% and 34.3%, respectively. The 5-year locoregional progression-free survival rate and overall survival rate of patients undergoing salvage surgery were 77.0% and 52.1% compared with 36.0% and 37.9% f3r patients treated with chemoradiotherapy and 0% and 0% for patients treated with radiotherapy alone, respectively. The 5-year locoregional progression free survival and overall survival of patients who recurred earlier than 24 months were higher (67.5% and 59.1%) than the other patients (39.5% and 24.9%). Among the 27 patients who didn't receive salvage surgery, there was no significant difference for locoregional progression free survival and overall survival between re-irradiated patients and radiation-naive patients. Conclusion: Surgical resection is preferred to treatment for locally recurrent rectal cancer. If salvage surgery is not possible, chemoradiotherapy may achieve higher locoregional progression free survival and overall survival than radiotherapy alone.

• Journal of Gastric Cancer
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• v.9 no.3
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• pp.143-151
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• 2009

Purpose: Gastric cancer is prevalent in Korea, therefore the purpose of this study was to determine the clinicopathologic characteristics, 5-year survival rate, and prognostic factors for gastric patients who underwent gastrectomy by a single surgeon. Materials and Methods: A total of 1,435 patients diagnosed with gastric cancer who underwent gastrectomy in the Department of Korean Gastric Cancer Center at Seoul Paik Hospital between September 1998 and August 2003, and the gender, age, location and size of the tumor, visual and histologic analysis, depth of invasion, lymph node metastasis, invasion (perineural, venous, and lymphatic), and surgical method were examined retrospectively. Results: The ratio between males and females was 2.29 : 1, and the average age was 56.7 years. Based on the UICC TNM classification, the patients were distributed as follows: IA 35.4%, IB 14.1%, II 12.6%, IIIA 12.3%, IIIB 8.3% and IV 17.3%. The 5-year survival rate was 69.6%. The results of univariate analysis showed that there were significant differences in the survival rate by age, location and size of tumor, Borrmann type, level of differentiation, Lauren's classification, depth of invasion, metastasis in lymph nodes, UICC TNM stage, invasion (perineural, venous, and lymphatic), and surgical method. Based on multivariate analysis, only the depth of invasion and lymph node metastasis were independent prognostic factors. Conclusion: Although various clinicopathologic characteristics affect the prognostic factors of the patients with gastric cancer, the results of this study showed that the stage of disease, such as depth of invasion and metastasis in lymph nodes, are the most critical factors. There is a need to establish the diagnosis of gastric cancer early and to study and develop various treatment methods based on the diagnostic factors in order to improve the survival of patients with gastric cancer.

• Radiation Oncology Journal
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• v.21 no.2
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• pp.125-134
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• 2003

Purpose: To report the early results of preopeartive concurrent radio-chemotherapy (CRCT) for treating rectal cancer. Materials and Methods: From June 1999 to April 2002, 40 rectal cancer patients who either had lesions with a questionable resectability or were candidates for sphincter-sacrificing surgery received preoperative CRCT. Thirty-seven patients completed the planned CRCT course. 45 Gy by 1.8 Gy daily fraction over 5 weeks was delivered to the whole pelvis in the prone position. The chemotherapy regimens were oral UFT plus oral leucovorin (LV) in 12 patients, intravenous bolus 5-FU plus LV in 10 patients, and intravenous 5-FU alone in 15 patients (bolus infusion in 10, continuous infusion in 5). Surgery was planned in 4$\~$6 weeks of the completion of the preoperative CRCT course, and surgery was attempted in 35 patients. Results: The compliance to the current preoperative CRCT protocol was excellent, where 92.5$\%$ (37/40) completed the planned treatment. Among 35 patients, in whom surgery was attempted after excluding two patients with new metastatic lesions in the liver and the lung, sphincter-preservation was achieved in 22 patients (62.9$\%$), while resection was abandoned during laparotomy in two patients (5.7$\%$). Gross complete resection was peformed in 30 patients, gross incomplete resection was peformed in one patient, and no detailed information on the extent of surgery was available in two patients. Based on the surgical and pathological findings, the down-staging rate was 45.5$\%$ (15/33), and the complete resection rate with the negative resection margin 78.8$\%$ (26/33). During the CRCT course, grade 3 $\~$4 neutropenia developed in four patients (10.8$\%$). Local recurrence after surgical resection developed in 12.1$\%$ (4/33), and distant metastases after the preoperative CRCT start developed in 21.6$\%$ (8/37). The overall 3-years survival rate was 87$\%$. Conclusion: Preoperative CRCT in locally advanced rectal cancer is well tolerated and can lead to high resection rate, down-staging rate, sphincter preservation rate, however, longer term follow-up will be necessary to confirm these results.