• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.2
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• pp.189-200
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• 2012

With increasing the number of smart device such as Tablet PC, smart phone and netbook, information security which based on smart device in mobile environment have become the issue. It is important to enter a password safety. In various types of mobile devices, because of hardware limitation of device, it is difficult that to equip secondary input device such as keyboard and mouse. Also, a loss of accuracy becomes a problem because input information was entered by touch screen. Because of problem mentioned above it can be predicted to change password scheme text based password scheme to graphical password scheme, graphical password scheme is easy to use and is resistant to shoulder surfing attack. So this paper proposes new graphical password scheme based 5 strokes which are made by decomposed the Korean to defend against shoulder surfing attack.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.2
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• pp.161-167
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• 2005

The improvements of the propulsive engine efficiencies could reduce the fuel consumption. Therefore. for a marine main diesel engine the substantial increase of stroke bore ratio. so that the engine speed can be significantly reduced in order to increase the Propulsive efficiency. As a typical example. a Sulzer RTA 60C engine has acylinder diameter of 600 mm and each cylinder is capable of delivering 2.369 kW in the speed range 91-114 rpm. In order to Provide basic data for thermal system of marine engine. this work performs an experimental study of heat transfer in a square channel with one rib-roughened wall under sin91e mode of reciprocating oscillation. A selection of heat transfer measurements illustrates the manner by which the reciprocating channel with two opposite heating walls has the higher heat transfer Performance than with four heating wall.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.745-751
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• 2009

Hypertension is a major risk factor for myocardial infarction, stroke, and cardiovascular mortality in adults; its treatment reduces the risk of cardiovascular events. In recent times, attention is being paid to monitoring of blood pressure from childhood to adulthood. Childhood hypertension is associated with hypertension in later life, and early intervention is important. In the Korean socioeconomic background, a rapid increase is observed in the number of obesity cases and the rate of increase in the incidence of obesity is more in childhood. The strong association of high blood pressure with obesity and the marked increase in the incidence of childhood obesity indicate that both hypertension and prehypertension are becoming significant health issues. In this comprehensive review, we acquaint the clinician with the available literature on childhood hypertension to provide recommendations for the diagnosis, evaluation, and treatment of hypertension based on the available evidence and consensus in Korean clinical conditions.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.3
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• pp.237-241
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• 2002

In this paper, we describe how to represent hand witten decimal digits by a sequence of one to five fuzzy sets. Each fuzzy set represents an arc segment of the digit and is a Cartesian product of four fuzzy sets; the first is fur the arc length of the segment, the second is for the arc direction, the third is fur the arc shape, and the fourth is a crisp number indicating whether it has a junction point and if it has an end point of a stroke. We show that an arbitrary pair of these sequences representing two different digits is mutually disjoint. We also show that various forms of a digit written in different styles can be represented by the same sequence of fuzzy sets and hence the deviations due to different writers can be modeled by using these fuzzy sets.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1694-1703
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• 2014

Lightning induced voltage is a major factor that causes interruptions on distribution lines. In this paper, analytical expressions are proposed to evaluate a lightning induced voltage on power lines directly in the time domain without the need to apply any extra conversions. The proposed expressions can consider the widely used current functions and models in contrast to the earlier analytical expressions which had a number of limitations related to the simplification of the channel base current and the current along the lightning channel. The results show that the simulated values based on the proposed method are in good agreement with the previous studies and the proposed expressions can be used for optimizing the insulation and protection level of existing and new lines being designed.

• Journal of the Korean Ceramic Society
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• v.30 no.2
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• pp.157-163
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• 1993

Hot pressing after cold cyclic compaction of Al2O3 powder mixtures containing SiC whiskers or Al2O3 short fibers is studied with emphasis on the effects of cold cyclic compaction. The green density of the mixtures increases as the cycle number increases and the cyclic pressure becomes higher. The higher green density is also obtained by cold cyclic compaction with the lower pressrue than a single stroke cold compaction. To achieve a higher densification during hot pressing, cold cyclic compaction before hot pressing is more efficient compared to the conventional hot pressing process (without cold cyclic compaction). Moreover, a low cyclic pressure did not affect on toughening mechanism by whisker reinforcement.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.3
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• pp.54-62
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• 1990

The thermodiluton is a standard method to measure cardiac output in clinical medicine. However it has many disadvantages such as expensive instrument and measurement, limited number of measurement, pain, safety problem, and side-effect due to insertion of catheter into heart. Electrical Impedance Cardiography has no such disadvantages and that it can continuously monitor stroke volume, contractility of cardiac muscle, and systolic time interval (STI) as well as cardiac output. While this impedance technique has been widely used and vigorously studied adroad, it is not introduced yet in Korea. Thus an Impedance Cardiograph has been developed in order to introduce this new technique. Its accuracy also has been verified by simultaneous measurement of cardiac output with the thermodilution technique. Finally changes of cardiac function during exercise were also measured.

• Annals of Clinical Neurophysiology
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• v.1 no.1
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• pp.70-75
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• 1999

Trancranial Doppler(TCD) monitoring is a new application of ultrasonography which allows the nonivasive detection of blood flow velocity in the horizontal (M1) segment of the middle cerebral artery (MCA) and detects microembolic phenomena in the cerebral circulation. Recent studies emphasized the potential of using this technique in vascular surgery (carotid endarterectomy, cardiopulmonary bypass), interventional and intensive care setting. Although the disparity between CBF and blood flow velocity and number of microemboli could be used to prevent cerebral ischemic and embolism based on clinical studies. A reduction of more than 60% of MCA can reflex hemodynamic ischemic state and acoustic feedback of high intensity transient signals(HITS) from the TCD monitoring unit has a direct influence on surgical technique. TCD monitoring can immediately provide information about thromboembolism and hemodynamic changes, which may be a useful tool in the study and prevention of stroke.

• Journal of Music and Human Behavior
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• v.2 no.2
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• pp.57-67
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• 2005

Most of stroke patients have not only physical difficulty but speech and neurological disorder because of hemiplegia and such unexpected changes cause psychologic disadaptability and absent-mindedness. Particularly, lowering of physical ability can lead to serious emotional problem from failure or frustration in daily life. Generally, treatment of patient with stroke put emphasis on physical rehabilitation but actually this patient had considerable speech disorder such as aphasia or articulation disorder. Moreover, failing of recognition function, mental disorder as hypochondria, and even visual and auditory disorder are represented. So it is effective to integrate verbal remediation and other treatments in medical care environment. In particular, patients with language disorder very often wither psychologically therefore it is efficient to use of music therapy that gives opulent emotion to aphasia patients. And primarily to investigate the effects of 10 sessions treatments; change in spoken total number of syllables, to confirm their own value by success of given task and reassure about themselves ability. All of 10 sessions stages were scored by MIT manual and its improvement were measured, that is, accomplishment was analyzed within each level in order to prove detail change of spoken total number of syllables. The result of this program organized from 2 syllables to 4 syllables is summarized as follows. Subject A completed in preliminary stage Level I, in 2 syllables case advanced to Level III in fifth session and to Level IV in seventh session, in 3 syllables case advanced to Level III in seventh session and to Level IV in ninth session, and in 4 syllables case showed 8% low success rate in first session but after repeated practice increased considerably in sixth session and in advanced to Level III in eighth session to Level IV in tenth session. Subject B also completed in preliminary stage Level I, in 2 syllables case advanced to Level III in forth session and to Level IV in sixth session, in 3 syllables case advanced to Level III in fifth session and to Level IV in seventh session, and in 4 syllables case showed 10% low success rate in first session and increased considerably in fifth session and in advanced to Level III in seventh session but could not reach to Level IV until tenth session. As a result, it was shown that music therapy using MIT was not statistically meaningful but improved spoken total number of syllables and success rate of task had improved as a whole. Therefore, music intervention using MIT it has positive affect on verbal ability of patients with Broca's Aphasia and their language rehabilitation.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.63-65
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• 2005

Because of simple principal and low cost, resistance spot welding has been used a lot for joining the sheet metal in automotive manufacturing process. Welding current, welding time, and force are the most important variables in resistance spot wording. Air guns have hem still used widely. The requirement of synchronizing between robot and weld-gun has become bigger as the field has been automated. The number of servo-gun in the field is trending upward because there're advantages as like to synchronize with robot and to control the stroke path and force by programming on servo-gun system. But no cleared force control method is suggested on servo-gun system until now. In this study, we proved the feedback current of the servo-motor can be used to an excellent force measuring sensor and the force is controlled by the feedback current. And we also detected force lowering during welding cycle on the servo-gun system and solved by compensated force control.