• Journal of the Korean Society for Railway
• /
• v.12 no.6
• /
• pp.1043-1048
• /
• 2009

PES (Programmable Electronic System) is used by software development for the train control system. PES has been widely used in real world and consists of hardware, firmware and application software. The PES are easily apply to many applications because its implementation has high flexibility. Many safety critical functions are realized through software in safety critical system. Normally, it is difficult to detect failures for PES system because the PES is too sophisticated to identify sources of the failure. So, the reliability analysis is needed by using software fault tolerance techniques. Currently, there are the recovery block, distributed recovery block, N-version programming, N self-checking programming in fault tolerance techniques. In this paper, the models of recovery block and N-version programming in software fault tolerance techniques are suggested by using the Markov model. Also, the reliability in the train control system is analyzed through changing time. The fault occupancy rates of the program, adjustment test and voter are stationary. So, the relation between time and reliability is presented by using Matlab program. In the result of reliability, the reliability of recovery block is more high than N-version programming in case of the same number of substitution block.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.35 no.11
• /
• pp.1036-1042
• /
• 2007

It is rather difficult to improve flight control computer(FLCC) hardware(H/W) development schedule due to lack of commercial off-the-self(COTS) tools or target specific tools. Thus, it is suggested to develop an enhanced process utilizing modeling, simulation and virtual reality tools. This paper presents H/W design process enhancement tool(PET) for FLCC design requirements such as FLCC input/output(I/O) signal flow, I/O fault detection, failure management algorithm, circuit logic, PCB assembly configuration and installation utilizing simulation and visualization in virtual space. New tool will provide simulation capability of various FLCC design configuration including shop replaceable unit(SRU) level assembly/dis-assembly utilizing open flight format 3-D modeling data.

• Restorative Dentistry and Endodontics
• /
• v.40 no.4
• /
• pp.299-305
• /
• 2015

Objectives: The purpose of this study was to investigate the effectiveness of multiple decontamination procedures for salivary contamination after curing of a universal adhesive on dentin bond strength according to its etch modes. Materials and Methods: Forty-two extracted bovine incisors were trimmed by exposing the labial dentin surfaces and embedded in cylindrical molds. A universal adhesive (All-Bond Universal, Bisco) was used. The teeth were randomly divided into groups according to etch mode and decontamination procedure. The adhesive was applied according to the manufacturer's instructions for a given etch mode. With the exception of the control groups, the cured adhesive was contaminated with saliva for 20 sec. In the self-etch group, the teeth were divided into three groups: control, decontamination with rinsing and drying, and decontamination with rinsing, drying, and adhesive. In the etch-and-rinse group, the teeth were divided into four groups: control, decontamination with rinsing and drying, decontamination with rinsing, drying, and adhesive, and decontamination with rinsing, drying, re-etching, and reapplication of adhesive. A composite resin (Filtek Z350XT, 3M ESPE) was used for filling and was cured on the treated surfaces. Shear bond strength was measured, and failure modes were evaluated. The data were subjected to one-way analysis of variation and Tukey's HSD test. Results: The etch-and-rinse subgroup that was decontaminated by rinse, drying, re-etching, and reapplication of adhesive showed a significantly higher bond strength. Conclusions: When salivary contamination occurs after curing of the universal adhesive, additional etching improves the bond strength to dentin.

• The Journal of the Korea Contents Association
• /
• v.13 no.11
• /
• pp.665-676
• /
• 2013

The present study analyzed the KOCCA's Game Immersion data to explore the relationship between psychological traits and game immersion. Psychological traits were classified into four categories; emotional stability, self-esteem, willpower, and happiness. These were put into the multiple regression analysis as the dependent variables with age, sex (dummy), economic status of the homes, variety of leisure activities, friend and family relationship, and time to play games. Four types of immersion (psychological unstability, bad relationship, interrupted daily lives, and failure to control game time and desire) were put into the multiple regression analysis as the independent variables. The multiple regression analysis indicated that the dependent variables predicted the game immersion. Among the psychological traits emotional stability was the strongest factor (negative) that influences the game immersion. Next powerful indicator (negative) among the psychological traits was self-esteem. Based on the findings, measures to alleviate the problems of game immersion and ideas for further research were suggested.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.11 no.1
• /
• pp.88-98
• /
• 2011

Lesch-Nyhan syndrome is a X-linked recessive disorder caused by a deficiency of the enzyme hypoxanthine-guanidine phosphoribosyltransferase (HPRT), enzyme to recycle purines. Case history: born induced vaginal delivery at 40 weeks complicated by premature membrane ruputure, body weight 2.820 gm. He showed failure to thrive showing severe protein aversion like milk products and pink daper. Developmental delay revealing rolling over at 10.5 month, followed by regression. Seizure at 2 months, His poor oral feeding was lifelong problem. Weak crying, spastic, choreoathetoid movement. Self mutilating behavior noted and diagnosed at age 3 years. No family history of consanguinity and neurological disorders. Method: Laboratory test, physical exam, imaging study and molecular. Clinical follow up Treat ment with allopurinol. Result: uric acid 10.5 mg/dL (N 3.5-7.9), APRT 151.1uM/ min/ml pro(25.7-101), HPRT 7.6 (N 233.5-701) and c.151C>T hemizygote (p,Arg51X). Abdominal sonogram showed staghorn calculi in both kidneys, brain MRI brain atrophy. Clinical follow up showed, seizure at 2 mo, developmental delay (head control and, rolling over at at 11mo, pointing body part at 2 yr 7 mo, eye hand coordination at 2 y 11mo,creeping at 3 y 7 mo, speaking words at 6 y 6 mo ),and developmental regression at 3 yr of age. Sleeping problem including insomnia and severe constipation. Self mutilating behavior (lip bite) started at 2.5 yr, neurologic sx including intermittent upward gaze accompanied by swallowing difficulty at 3 y 7 mo grand mal seizure at 4.5 yr and spastic extremity and trunchal hypotonia and choleoathetoid movement and ataxia at 6.5 yr. Scoliosis with severe spasticity at 9 yr 9 mo. Acute life threatening episode with irregular breathing at 9 yr and 9 mo, Emaciation and nephrolithiasis and recurrent pneumonia. Died suddenly at 10 yr 3 mo. Conclusion: life long feeding problem, chronic gut motility dysfunction, sleeping difficulty and progressing neurologic deterioration and nephrolithiasis despite normal serum uric acid maintence by allopurinol treatment.

• Journal of Digital Convergence
• /
• v.13 no.9
• /
• pp.277-286
• /
• 2015

The purpose of this study is to analyze the effects of creativity instruction activities on academic motivation and career maturity of university students and the relationship between these factors. The subjects of this study were university students who took creativity liberal arts based on NFTM-TRIZ creativity education model for a term. The research scales were the self-efficacy scale and failure tolerance scale of academic motivation tests and the Career Maturity Inventory Attitude Scale. The results of this study were as follows : First, creativity instruction activities had a positive influence on academic motivation and career maturity. Especially the effects on self control efficacy, task preference level, career decisiveness and compromise showed significantly(p<.01). Secondly, academic motivation showed positive relationship with career maturity(p<.05).

• Journal of Korea Game Society
• /
• v.10 no.3
• /
• pp.47-59
• /
• 2010

Differing from most of current studies which recognizing game item cash-trade as simple static system, this study approaches game item cash-trade as Complex Adaptive System through historical analysis. The item-trade is a complex phenomenon converging between cyber-economy and real-economy, and production and consumption process of game-item are evolving dynamically over time. The results are following: first, the early item-trade emerges in endogenously rather than results from purposed system designed by singular actor. Second, after the early item-trade, the trade system as a CAS which various voluntary actors(single user, factory, game company, user community, agency, etc.) participates in is self-organizing for trading safety and efficiency. Third, the complex adaptive item-trade system satisfies actor's needs interdependently and accelerate positive feedback powerfully. This study implies that purposeful control disregarding emergent adaptive item-trade system distorts system efficiency and can lead to unintended policy failure.

• Restorative Dentistry and Endodontics
• /
• v.48 no.2
• /
• pp.14.1-14.11
• /
• 2023

Objectives: This study investigated the effect of an aluminum chloride hemostatic agent on the shear bond strength (SBS) of a universal adhesive to dentin. Materials and Methods: Eighty extracted human molars were trimmed at the occlusal dentin surfaces and divided mesiodistally. According to hemostatic agent application, specimens were randomly allocated into control (C) and hemostatic agent (Traxodent; H) groups. Each group was divided into 4 subgroups according to the adhesive system (n = 20): Scotchbond Multi-Purpose (SBER), Clearfil SE Bond (CLSE), All-Bond Universal etch-and-rinse mode (ALER), and All-Bond Universal self-etch mode (ALSE). SBS was measured for half of the specimens at 24 hours, and the other half were thermocycled in water baths (group T). Fracture surfaces were examined to determine the failure mode. The SBS was measured, and data were analyzed using 1-way analysis of variance, the Student's t-test, and the Tukey honestly significant difference test (p = 0.05). Results: No significant differences in SBS were found between groups C and H for any adhesive system at 24 hours. After thermocycling, a statistically significant difference was observed between CT+ALSE and HT+ALSE (p < 0.05). When All-Bond Universal was applied to hemostatic agent-contaminated dentin, the SBS of H+ALSE was significantly lower than that of H+ALER (p < 0.05). The SBER subgroups showed no significant differences in SBS regardless of treatment and thermocycling. Conclusions: When exposed dentin was contaminated by an aluminum chloride hemostatic agent before dentin adhesive treatment, application of All-Bond Universal in etch-and-rinse mode was superior to self-etch mode.

• Journal of Korea Society of Industrial Information Systems
• /
• v.19 no.4
• /
• pp.33-39
• /
• 2014

In this paper, a new on-chip aging sensing circuit based on flip-flops is proposed to detect a circuit failure of MOSFET digital circuits casued by aging phenomenon such as HCI and BTI. The proposed circuit uses timing windows to warn against a guardband violation of sequential circuits, and generates three warning bits right before circuit failures occur. The generated bits can apply to an adaptive self-tuning method for reliable system design as control signals. The aging sensor circuit has been implemented using 0.11um CMOS technology and evaluated by $4{\times}4$ multiplier with power gating structure.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.21 no.2
• /
• pp.548-553
• /
• 2007

In general, cancer pain is neither fully recognized nor adequately treated. The inadequate pain control is due to failure of accurate assessment of cancer pain. This study was aimed to understand various characters of cancer pain and investigate available assessment scales which have been designed for, or frequently used with people with cancer pain. A total of 23 articles were selected from two different databases. The selected articles were analyzed according to three aspects of initial assessment, patient self-report and assessment of the outcomes of pain management. The characters of cancer pain is complex and includes physical, psychosocial, and spiritual dimension. Also, subjective pain can be classified into at least four specific factors, such as pain intensity, pain affect, pain relief, and pain quality. Based on various classification, the pain assessment scales can be divided into unidimensional or multidimensional. Among the more commonly used clinical tools are numeric rating scales, verbal rating scales, visual analog scales, and picture scales. Above all, in order to assess cancer pain objectively, the clinician must select appropriate assessment instruments which reflect pain definition and clinical purpose.