• Journal of Institute of Control, Robotics and Systems
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• v.17 no.12
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• pp.1256-1265
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• 2011

Automated parking assist systems are being commercialized and rapidly spread in the market. In order to improve odometry accuracy, we proposed a practical odometry calibration scheme of Car-Like Mobile Robot (CLMR). However, there were some open problems in our prior work. For example, it was not clear whether the kinematic parameters always converged or not using the proposed calibration scheme. In addition, test driving had to be carried out "twice" without detailed explanation. This research aims to provide answers for the addressed questions though the convergence property analysis of the calibration scheme. In this paper, we evaluate on the effect of the kinematic parameter error on the odometry error at the final pose by numerical computation. The evaluation will show that the wheel diameter and tread of the CLMR can be calibrated by iterative test drives. In addition, the region of convergence in the parametric space will be discussed. Presented experimental results clearly showed that the proposed calibration scheme would be useful in practical applications.

• Journal of Chest Surgery
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• v.24 no.1
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• pp.8-14
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• 1991

Methods for the operative management of patent ductus arteriosus are now well established, and in the vast majority of children the circulatory shunt can be safely and effectively abolished by dividing the ductus or by closing it in continuity with ligatures and transfixing sutures. In adults, however, closure of patent ductus arteriosus may pose important technical problems, particularly when there are associated pulmonary hypertension, calcification, aneurysm and infective endocarditis. Under these circumstance, division or ligation is unusually hazardous because the diseased vessels often fracture or tear when sutures are placed in them. Then we closed the patent ductus arteriosus by use of cardiopulmonary bypass in 18 patients and ligated the ductus via thoracotomy in 18 patients from Jan. 1986 to May 1990. And we compared the results between two different methods. We concluded that ligation of ductus had a problem of rupture and transpulmonary internal suture closure of PDA had a problem of injury of recurrent laryngeal nerve.

• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.300-309
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• 2016

This paper proposes a method for motion estimation of consecutive cameras using 3-D straight lines. The motion estimation algorithm uses two non-parallel 3-D line correspondences to quickly establish an initial guess for the relative pose of adjacent frames, which requires less correspondences than that of current approaches requiring three correspondences when using 3-D points or 3-D planes. The estimated motion is further refined by a nonlinear optimization technique with inlier correspondences for higher accuracy. Since there is no dominant line representation in 3-D space, we simulate two line representations, which can be thought as mainly adopted methods in the field, and verify one as the best choice from the simulation results. We also propose a simple but effective 3-D line fitting algorithm considering the fact that the variance arises in the projective directions thus can be reduced to 2-D fitting problem. We provide experimental results of the proposed motion estimation system comparing with state-of-the-art algorithms using an open benchmark dataset.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.5
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• pp.557-564
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• 2012

This paper presents UGV localization using multi-sensor fusion based on federated filter in outdoor environments. The conventional GPS/INS integrated system does not guarantee the robustness of localization because GPS is vulnerable to external disturbances. In many environments, however, vision system is very efficient because there are many features compared to the open space and these features can provide much information for UGV localization. Thus, this paper uses the scene matching and pose estimation based vision navigation, magnetic compass and odometer to cope with the GPS-denied environments. NR-mode federated filter is used for system safety. The experiment results with a predefined path demonstrate enhancement of the robustness and accuracy of localization in outdoor environments.

• Journal of Environmental Health Sciences
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• v.35 no.3
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• pp.235-238
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• 2009

In Korea, talc that has been widely used for a lot of consumer products as well as industrial usage until recently was found to be contaminated with asbestos. It becomes a major social issue. Critical health risk about both talc and talc contaminated with asbestos was summarized through literature review. It has been confirmed that talc can pose ovarian cancer when talc powder is used in the genital area. International Agency for Research on Cancer (IARC) already concluded that the perineal use of cosmetic talc can cause possibly carcinogenic to humane(Group 2B), although there was study reporting the lack of a consistent an established correlation between perineal dusting frequency and ovarian tissue talc concentrations and the lack of a consistent dose-response relationship with ovarian cancer risk. The association between talc exposure and ovarian cancer is as strong as in recent studies. The epidemiological studies to date provided inadequate evidence for the carcinogenicity of either inhaled or ingested talc that does not contain asbestos or asbestosiform fibers. Future studies should focus on seeking evidence in talc-exposed populations, collecting reliable information on age at initial used of body powder, exposure assessments related to talc use and dose response relationship in order to identify possible risk of talc ingested or inhaled.

• Journal of Chest Surgery
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• v.19 no.1
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• pp.12-17
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• 1986

The pericardial adhesions following the first open heart surgery pose a major problem that can increase the morbidity and mortality in cases of reoperation because of the danger of damaging the heart, great vessels or grafts. The purpose of this study was to determine the effect of intrapericardial infusion of 5% dextrose solution and heparin on experimental pericardial adhesions. The 15 white rabbits were divided into three treatment groups of 5 animals each: group 1 [control group], group 2[5% dextrose group] and group 3 [heparin group]. At 4 weeks, all animals were sacrificed and the pericardial adhesions were graded as follows: 1[none], ll[mild], Ill[moderate] and IV[severe]. Histological examination was performed on a subset of each group. The difference of adhesion between control and heparin group was evaluated by Chi-square analysis. The results were as follows: 1. Pericardial adhesions developed in 80% of animals in group 1 and 2. 2. Only 40%> of animals in group 3 had mild to moderate pericardial adhesions. This was significantly different from the control group [P=0.01]. 3. Histological examination showed that the pericardium with adhesion was thickened with fibrosis, while that without adhesion was thin, normal appearance. 4. In group 3, there was no evidence of hemorrhage or hemorrhagic tendency in the pericardium.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.213-218
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• 2021

This paper proposes a technique for detecting a significant threat that attempts to get sensitive and confidential information such as usernames, passwords, credit card information, and more to target an individual or organization. By definition, a phishing attack happens when malicious people pose as trusted entities to fraudulently obtain user data. Phishing is classified as a type of social engineering attack. For a phishing attack to happen, a victim must be convinced to open an email or a direct message [1]. The email or direct message will contain a link that the victim will be required to click on. The aim of the attack is usually to install malicious software or to freeze a system. In other instances, the attackers will threaten to reveal sensitive information obtained from the victim. Phishing attacks can have devastating effects on the victim. Sensitive and confidential information can find its way into the hands of malicious people. Another devastating effect of phishing attacks is identity theft [1]. Attackers may impersonate the victim to make unauthorized purchases. Victims also complain of loss of funds when attackers access their credit card information. The proposed method has two major subsystems: (1) Data collection: different websites have been collected as a big data corresponding to normal and phishing dataset, and (2) distributed detection system: different artificial algorithms are used: a neural network algorithm and machine learning. The Amazon cloud was used for running the cluster with different cores of machines. The experiment results of the proposed system achieved very good accuracy and detection rate as well.

• Kyungpook Mathematical Journal
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• v.61 no.4
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• pp.745-763
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• 2021

For a value s ∈ ℂ∪ {∞}, two meromorphic functions f and g are said to share the value s, CM, (or IM), provided that f(z)-s and g(z)-s have the same set of zeros, counting multiplicities, (respectively, ignoring multiplicities). We say that a meromorphic function f shares s ∈ Ŝ partially with a meromorphic function g if E(s, f) ⊆ E(s, g). It is easy to see that "partially shared values CM" are more general than "shared values CM". With the help of partially shared values, in this paper, we prove some uniqueness results between a non-constant meromorphic function and its generalized differences or shifts. We exhibit some examples to show that the result of Charak et al. [8] is not true for k = 2 or k = 3. We find some gaps in proof of the result of Lin et al. [24]. We not only correct these resuts, but also generalize them in a more convenient way. We give a number of examples to validate certain claims of the main results of this paper and also to show that some of conditions are sharp. Finally, we pose some open questions for further investigation.

• Geotechnical Engineering
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• v.1 no.2
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• pp.41-54
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• 1985

Generally, ground settlements and lateral displacements are accompanied by underground excavation associated with open-cut or tunnling. These ground movements cause a harmful influence upon nearby super.structures and sub-structures. Occasionally, the ground movements may pose serious problems as the function of the nearby structures may be disrupted. Therefore, prior to the subway construction in an urban area, it is necessary to identify the causes of ground settlements and estimating the extent St the magnitude of ground movements since any potential damage to the nearby structures such as gas lines, water mains, high buildings and cultural assets must be assessed. The research was performed mainly on ground movements such as surface settlements, lateral displacements, subsurface settlements and crown settlements to predict the maximum settlement and settlement zone, and to identify the causes of ground settlements in NATM sections of Busan subway. As a result, it was found that lateral distribution of settlements could be approximated reasonably by a Gaussian normal probability curve and longitudinal distribution of settlements by a cumulative Gaussian probability curve, and that the early closure of temporary invert was very important to minimize ground settlements.

• Archives of Plastic Surgery
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• v.42 no.4
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• pp.431-437
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• 2015

Background Repair of facial laceration in the emergency department can pose a number of difficulties. Children can be uncooperative, but adults can also be if they have sustained head trauma or are intoxicated. Leukosan SkinLink consists of topical adhesive and adhesive tape that can be applied easily to long or tense wounds. In this study, the authors compared conventional suturing with Leukosan SkinLink for facial laceration patients in the emergency department. Methods The prospective study was carried out from March 2013 to September 2013 with linear facial laceration patients visiting the emergency department. Exclusion criteria were open fractures, joint injuries, skin defects, hairy skin, and mucosa. The author used Leukosan SkinLink for skin closure in the experimental group and used conventional suturing in the control group. The scar evaluation using the Patient and Observer Scar Assessment Scale (POSAS) along with satisfaction scores, procedure times, and complications were compared. Results A total of 77 patients (30 in the control group and 47 in the experimental group) participated and underwent follow-up for 6 months postoperatively. The scar assessment using the POSAS and the satisfaction score in both groups were similar. The average procedure time in the experimental group was shorter. In the control group, there were four cases of wound dehiscence, two of infection, and one of skin necrosis, whereas four cases of wound dehiscence and one allergic reaction occurred in the experimental group. Conclusions With a simple application technique, Leukosan SkinLink is a new effective method for facial laceration repair especially useful for children and uncooperative adults.