• Journal of Navigation and Port Research
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• v.43 no.3
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• pp.143-152
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• 2019

In this paper, the towing stability of the LNG bunker barge was estimated. Currently, LNG bunkering barge is being developed for the bunkering of LNG (Liquefied Natural Gas), an eco-friendly energy source. Since the LNG bunkering barge assumes the form of a towed ship connected to the tow line, the towing stability of the LNG bunker barge is crucial f not only for the safety of the LNG bunker barge but also the neighboring sailing vessels. In the initial stages, a numerical code for towing simulation was developed to estimate the towing stability of the LNG bunkering barge. The MMG (Maneuvering Mathematical modeling Group) model was applied to the equations of motion while the empirical formula was applied to the maneuvering coefficients for use in the initial design stage. To validate the developed numerical code, it was compared with published calculation and model test results. Towing simulations were done based on the changing skeg area and the towing position of the LNG bunkering barge using the developed numerical codes. As a result, the suitability of the designed stern skeg area was confirmed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.1
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• pp.109-115
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• 2019

In arc-welding applying to the present automobile part manufacturing process, a wrist-hollow type arc welding robot can shorten the welding cycle time, because feedability of a welding wire is not affected by a robot posture and thus facilitates high-quality arc welding, based on stable feeding with no entanglement. In this paper, we will propose the optimization of wrist design for a wrist-hollow type 6-Axis articulated robot. Specifically, we will perform the investigation on the optimized design of inner diameter of hollow arms (Axis 4 and Axis 6) and width of the upper arm by using the simulation of robot motion characteristics, using a Genetic Algorithm (i.e., GA). Our simulations are based on $SolidWorks^{(R)}$ for robot modeling, $MATLAB^{(R)}$ for GA optimization, and $RecurDyn^{(R)}$ for analyzing dynamic characteristics of a robot. Especially $RecurDyn^{(R)}$ is incorporated in the GA module of $MATLAB^{(R)}$ for the optimization process. The results of the simulations will be verified by using $RecurDyn^{(R)}$ to show that the driving torque of each axis of the writs-hollow 6-axis robot with the optimized wrist design should be smaller than the rated output torque of each joint servomotor. Our paper will be a guide for improving the wrist-hollow design by optimizing the wrist shape at a detail design stage when the driving torque of each joint for the wrist-hollow 6-axis robot (to being developed) is not matched with the servomotor specifications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.337-342
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• 2010

Generally most sluice gates are closed and opened by a mechanical winch, a winch using an oil-pressure, or a winch mixing both. Because of their size and structure, they should be safely operated with more than two pulling devices helping each other. At the moment of their opening and closing, there usually occur some additional loads to the structure which cannot be exactly measurable at the stage of designing. Such additional loads can cause the sluice gate to be unbalanced and make it hard to open and close the gate, and by also overloading a winch, they can inflict a significant damage to the safety of the sluice gate. This paper explains a FDC(Force-Displacement Control) system which simultaneously considered the oil-pressure and displacement in order to evenly distribute the force and make a winch balanced at the opening and closing motion. This FDC system was implemented by means of the PID(Proportional Integral Derivative) function of XG 5000 program. It was experimented on a model of the sluice gate winch with the hydraulic oil pressure cylinder. The experiments showed that the developed FDC system made the winch of hydraulic oil pressure cylinder open and close cooperatively in spite of various external loads. Therefore the FDC system is proven effective when it is applied to a winch of sluice gate.

• Korean Journal of Legislative Studies
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• v.27 no.2
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• pp.71-109
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• 2021

The purpose of this study is to find out what factors influence lawmakers' voting decisions in the plenary session. In particular, the study examines causes and characteristics of waffling and strategic waffling, which express opposition or abstention in a discharge petition or a vote at the plenary session despite participating in a bill sponsorship. The study on waffling is meaningful because it has not been covered in previous literatures. To this end, the Gadeokdo New Airport Special Act, which the National Assembly passed in February 2021, was set as an analysis target. The study examined the factors that affected legislators' voting decisions and participation in bill sponsorship and who were related with waffling. Statistical results showed that the age variable influenced the motion of the bill while seniority and party affiliation had an effect on the participation of the bill. Likewise, the study found that party affiliation and district had an influence on the approval of the bill. In addition, the analysis of waffling showed that lawmakers with higher seniority tended not to participate in the vote. It could be interpreted that lawmakers with more legislative experience judged that they would benefit from strategic waffling. There is a limit to understanding lawmakers' decision-making and waffling through a limited analysis of the Gadeokdo New Airport bill. However, given that lawmakers tend to choose avoidance strategies in ambiguous situations, and given the high intelligence of lawmakers who know better than anyone about the future impact of a new bill, the decision-making shown by lawmakers in each stage of the situation is a prudent judgment gained from their experience. It indicates that it is necessary to research the legislative activities of lawmakers in various ways.

• Journal of Veterinary Clinics
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• v.41 no.2
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• pp.71-78
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• 2024

Changes in elimination behavior, including urination and defecation, are common clinical signs of numerous disorders in cats. Therefore, this study attempted to automatically measure the elimination behavior of cats using the litter box and develop an early warning system for the guardian in case of abnormalities. To construct an early warning system for abnormal changes through cat elimination behavior, it consisted of a litter box, an automatic sensor for data collection and data wifi transmission, a server for data analysis, and a mobile phone app for result transmission and early warning. To establish the reference interval (RI), the elimination behavior was monitored for more than 2 weeks using a motion sensor within a litter box in 37 healthy cats and 19 diseased cats. The data were expressed as daily total visits, daily total stay duration, average stay duration per elimination, weekly total visits, and weekly total stay duration. Healthy cats showed median daily total visits of 3 times/day (RI 1.0-7.0) and daily total stay duration of 192 s/day (RI 8.0-452.0). For weekly data, the median total visits were 20 times/week (RI 3.0-35.25) and the median total stay duration was 1,147 s/week (RI 80.0-2,249.5). The average stay duration per elimination was 59 s/elimination (RI 4.67-132.0). Diseased cats showed more frequent elimination behavior than healthy cats (p < 0.001). Otherwise, for each elimination, diseased cats had shorter stay durations than healthy cats (p < 0.001). This study established the RIs of elimination behavior parameters (frequency and duration) in healthy cats. The present study might help guardians and veterinarians detect changes in elimination behaviors in diseased cats at an early stage.

• Radiation Oncology Journal
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• v.25 no.1
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• pp.26-33
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• 2007

[ $\underline{Purpose}$ ]: The aim of this study is to evaluate and compare the incidence and aspects of myocardial perfusion defects in patients who were subjected to either two-dimensional or three-dimensional simulation techniques for early left-sided breast cancer. The myocardial perfusion defects were determined from using single photon emitted computerized tomography (SPECT) myocardial perfusion images. $\underline{Materials\;and\;Methods}$: Between January 2002 and August 2003, 32 patients were enrolled in this study. The patients were diagnosed as having early (AJCC stage T1-T2N0M0) left-sided breast cancer and were treated with tangential irradiation after breast-conserving surgery and systemic chemotherapy. The patients were divided into two groups according to the type of simulation received: two-dimensional simulation using an X-ray fluoroscope simulator or three-dimensional simulation with a CT simulator. All patients underwent technetium-99m-sestamibi gated perfusion SPECT at least 3 years after radiotherapy. The incidence and area of myocardial perfusion defects were evaluated and were compared in the two groups, and at the same time left ventricular ejection fraction and cardiac wall motion were also analyzed. The cardiac volume included in the radiation fields was calculated and evaluated to check for a correlation between the amount of irradiated cardiac volume and aspects of myocardial perfusion defects. $\underline{Results}$: A myocardial perfusion defect was detected in 11 of 32 patients (34.4%). There were 7 (46.7%) perfusion defect cases in 15 patients who underwent the two-dimensional simulation technique and 4 (23.5%) patients with perfusion defects in the three-dimensional simulation group (p=0.0312). In 10 of 11 patients who had myocardial perfusion changes, the perfusion defects were observed in the cardiac apex. The left ventricular ejection fraction was within the normal range and cardiac wall motion was normal in all patients. The irradiated cardiac volume of patients in the three-dimensional simulation group was less than that of patients who received the two-dimensional simulation technique, but there was no statistical significance as compared to the incidence of perfusion defects. $\underline{Conclusion}$: Radiotherapy with a CT simulator (three-dimensional simulation technique) for early left-sided breast cancer may reduce the size of the irradiated cardiac volume and the incidence of myocardial perfusion defects. Further investigation and a longer follow-up duration are needed to analyze the relationship between myocardial perfusion defects and clinical ischemic heart disease.

• (The) Research of the performance art and culture
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• no.37
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• pp.5-31
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• 2018

The mask dance drama Goseong Ogwangdae's first act, Mundung Bukchum. The story is about a man who was born to the upper class but contracted leprosy, an incurable disease, due to his ancestors' accumulated sin. Although he is suffering, he is able to triumph over the disease through sinmyeong (catharsis) that is expressed through the wordless act of Mundung Bukchum. This thesis focuses on Goseong Ogwangdae's Mundung Bukchum, particularly the meaning, costume, accompanying music, and process of pedagogical transmission. The chronological characteristics of Goseong Ogwangdae's Mundung Bukchum are as follows. First, as time goes on, the number of dance motions in Mundung Bukchum has increased and the motions used have become reified. Second, I address the small barrel drum used in Mundung Bukchum and check how, through the drum, the changed expression of Mundung is shown.In a 1965 video introduced Mundung is grasping the drum and stick and the dance appears to be made up only of humorous motions. Also in a 1969 video, "Mundung Gwangdae," from the start Mundung is grasping the drum and stick. In 1988 in a video we can see the same scene as today, with the drum and stick sitting in the center of the stage at the start of the dance. We can also confirm that the same fourteen dance motions used today are present. Third, we can also confirm the changes in Goseong Ogwangdae's signature motion, baegimsae as time goes on. Observing the video from 1965, baegimsae does not appear in Mundung Bukchum. In 2000 we can clearly see the baegimsae performed once to the left and to the right while Mundung is squatting. Comparing 1969 to 1988, there is no symmetry in the motions, baegimsae is not done to both left and right, but only in one direction. Watching the record from 2000, the baegimsae motion is performed just as it is now, with the body thrown forward with a sharp push off the ground. Fourth I confirmed how the music used to accompany Goseong Ogwangdae's Mundung Bukchum has changed over time. In 1965 according to records of Mundung Bukchum's appearance, the dance was accompanied by the taryeong rhythmic pattern played on the usual four percussion instruments (barrel drum, hourglass drum, large gong, small gong). In the 1969 records of Mundung Bukchum the accompanying music is gutgeori rhythmic pattern performed on the usual four percussion instruments-an obvious difference. In 1988 the music with Mundung Bukchum is gutgeori rhythmic pattern transitioning into jajinmori rhythmic pattern. In 2000 the music with Mundung Bukchum includes the percussion instruments as well as taepyeongso (double reed oboe) playing gutgeori and jajinmori rhythmic patterns.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.52-58
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• 2019

Purpose: Fungal periprosthetic joint infection (PJI) is a rare but devastating complication following total knee arthroplasty (TKA). On the other hand, a standardized procedure regarding an accurate treatment of this serious complication of knee arthroplasty is lacking. The clinical progress of staged reimplantation in patients who had fungus-related PJI after TKA was reviewed retrospectively. Materials and Methods: Ten patients who had a fungal related PJI after TKA between 2006 and 2017 using staged reimplantation surgery were reviewed. These patients were compared with 119 patients who had a PJI in the same period. The failure rate of infection control, intravenous antimicrobial using the period, and the clinical results were evaluated by comparing the range of motion and Korean knee score (KKS) between pre-staged reimplantation and the last follow-up. Results: In the fungal infection group, 7 out of 10 cases (70.0%) had failed in infection control using staged reimplantation and in the non-fungal group, 7 out of 119 cases (5.9%) had failed (p=0.04). In the non-fungal group, the mean duration of antibiotics was 6.2 weeks. In the fungus group, the mean duration of antibiotics was 15.3 weeks, which was 9.1 weeks longer (p<0.001). The range of motion of the knee was increased in the two groups (p=0.265). At the last follow-up, the KKS was 71.01 points in the non-fungal group and 61.3 points in the fungal group (p=0.012). Erythrocyte sedimentation rate and C-reactive protein (CRP) decreased in the two groups, but the CRP was significantly different in the two groups (p=0.007). Conclusion: The treatment of fungus-related PJIs using staged reimplantation showed uneven clinical progress and unsatisfactory clinical improvements compared to non-fungal PJI. Therefore, it is necessary to consider the use of an antifungal mixed cement spacer at resection arthroplasty and oral antifungal agent after reimplantation.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.85-89
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• 2014

Arterial thromboembolism (ATE) is a common and fatal complication of hypertrophic cardiomyopathy (HCM) in cats. Therefore in this study, we evaluated the hypercoagulability (using plasma concentration of D-dimer) in HCM cats with different stage of heart failure and left atrial enlargement and also investigated the any correlation with echocardiographic indices (including left free wall thickness at diastole, interventricular septal thickness at diastole, LA to Ao ratio, heart failure stage, existence of systolic anterior motion of mitral valve). The median plasma D-dimer concentration in this study population was $0.51{\pm}0.70$ (range 0 to 2.50) ug/mL in the control group, $1.47{\pm}1.29$ (range 0.3 to 5.79) ug/mL in the HCM group, $1.48{\pm}1.65$ (range 0.3 to 5.79) ug/mL in the ISACHC I group, $1.62{\pm}0.4$ (range 1.31 to 2.07) ug/mL in the ISACHC II group, $1.36{\pm}0.91$ (range 0.3 to 2.31) ug/mL in the ISACHC III group, $1.90{\pm}1.60$ (range 0.3 to 5.79) ug/mL in the cat with LA dilation, $1.72{\pm}0.72$ (range 0.6 to 2.31) ug/mL in cats with SEC-T, $1.19{\pm}0.70$ (range 0.3 to 2.31) ug/mL in the cats with SAM, and $1.63{\pm}0.80$ (range 0.6 to 2.31) ug/mL in the cats with ATE. Our study found the median and mean concentration of plasma D-dimer was higher in cat with HCM, ATE, SECT and SAM and clearly provides evidence of hypercoagulability in cats with HCM, although the severity was not correlated to the dilation of LA and the presence of heart failure. This is the first study evaluating the hypercoagulability in cats with HCM in Korea.

• The Journal of the Korean bone and joint tumor society
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• v.7 no.2
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• pp.51-58
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• 2001

Purpose : In patients having malignant and aggressive bone tumors around knee joint requiring amputation, segmental resection and rotationplasty were performed and the clinical results were analyzed. Materials and Methods : Twenty-six patients underwent segmental resection and rotationplasty between February 1988 and June 1994, because limb salvage with tumor prosthesis after removal of tumor was impossible. The mean follow-up of malignant tumors was 57(6~120) months and the average age of patients was 21.4(5~37) years old. Out of 26 patients, there were 18 osteosarcoma(${\geq}$stage IIB), 2 synovial sarcoma, and 6 giant cell tumor. Results : Clinical results were evaluated by the Shriner's rating system. Four patients were excluded due to death or amputation and remaining 22 patients were included for assessment. Eighteen patients had excellent result, 3 good, and 1 fair. Range of motion of ankle joint was -11(dorsiflexion)~80(plantarflexion) degrees and daily walking activity with prosthesis was possible. Local recurrence developed in 2 patients and distant metastasis in 10. Early complications had 3 thrombosis and 1 sepsis, and late complications had 6 nonunion, 2 malrotation and 1 stiffness of ankle joint. Conclusion : Rotationplasty which is functionally excellent may serve as an effective partial limb salvage procedure, especially in patients less than 10 years old that lower extremity discrepancy or loosening tumor prosthesis due to enlargement of medullary cavity are anticipated or amputation is inevitable for wide resection margin.