• MALSORI
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• no.45
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• pp.1-14
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• 2003

This paper criticizes S. Kim (1992), claiming that the perception of place cues in the reduced stop consonant clusters ('reducing' means 'cutting off' the acoustic silence in stop clusters) largely depends on the acoustic characteristics such as formant transition and noise frequency distribution of stop burst, rather than the closure duration time as advocated by S. Kim (1992). The claim is based on the perception test conducted upon 111 stimuli over 10 subjects. The finding is that, when the closure duration is cut off up to the point where only one stop is perceived, place of the second stop, not the first one, in the cluster is in most cases perceived regardless of the places of the first and second stops. It is likely that the place cues of the stop in the prevocalic position mask those in the postvocalic position.

• Asia pacific journal of information systems
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• v.13 no.4
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• pp.191-206
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• 2003

More views in data warehouse, can respond to the users more rapidly because the user's requests might be processed by accessing only the materialized views with higher probabilities rather than accessing base relations. But, the update duration for maintaining materialized views limits the number of materialized views in data warehouse. In this paper, we propose the algorithm for reducing update duration of materialized views, of which aggregation functions are maintained by self-maintenance. We also implement the proposed algorithm and evaluate the performance of the algorithm.

• Restorative Dentistry and Endodontics
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• v.38 no.1
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• pp.43-47
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• 2013

Objectives: The aim of this study was to determine an appropriate application duration of sodium ascorbate (SA) antioxidant gel in reducing microleakage of bonded composite restoration in intracoronally-bleached teeth. Materials and Methods: Eighty endodontically-treated human incisors were randomly divided into eight groups: control, no bleaching; IB and DB, immediate and delayed bonding after bleaching, respectively; S10m, S60m, S24h, S3d and S7d, bleaching + SA gel for 10 min, 60 min, 24 hr, 3 day and 7 day, respectively. For bleaching, a mixture of 30% hydrogen peroxide and sodium perborate was applied for 7 day. All access cavities were restored using One-Step adhesive (Bisco Inc.) and then Aelite LS Packable composite (Bisco Inc.). The bonded specimens were subjected to 500 thermal cycles, immersed in 1% methylene blue for 8 hr, and longitudinally sectioned. Microleakage was assessed with a 0 - 4 scoring system and analyzed using nonparametric statistical methods (${\alpha}$ = 0.05). Results: Group IB showed a significantly higher microleakage than the control group (p = 0.006) and group DB a statistically similar score to the control group (p > 0.999). Although groups S10m, S60m, and S24h exhibited significantly higher scores than group DB (p < 0.05), the microleakage in groups S3d and S7d was statistically similar to that in group DB (p = 0.771, p > 0.999). Conclusions: Application of SA gel for 3 day after nonvital bleaching was effective in reducing microleakage of composite restoration in intracoronally-bleached teeth.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.2
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• pp.278-286
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• 2009

Restaurants have two strategic levers for revenue management: duration control and demand-based pricing. Reducing dining times, especially during peak periods, can add considerable revenue for restaurants. Managing meal duration, however, can be far more complex than manipulating the price. This paper examines dining duration expectations for restaurants types(Family, Korean, Quick service restaurant), customers characteristics(gender, age, occupation, meal period, visiting frequency, dining occasion, dining companions) using an a adaptation of a price sensitivity measurement tool, naming it 'Time Sensitivity measurement tool' or TSM. The TSM is then used to derive the optimal time points, and the range of acceptable times. The results demonstrate that there is a relatively wide spread of acceptable dining duration times in family restaurant. Furthermore, the optimal time points was shorter than the mean expected dining times, which suggests that many restaurants may be able to shorten dining duration without compromising customer satisfaction. The paper explores whether demographic and dining variables have an impact on time preferences, and finds whether gender, age, meal periods, visiting frequency, and dining companion effects are significant. Specifically, women in their thirties tended to prefer a significantly longer dining times for dinner.

• Earthquakes and Structures
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• v.1 no.4
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• pp.327-344
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• 2010

This paper summarizes results of a comprehensive analytical study aimed at evaluating the influence of strong ground motion duration on residual displacement demands of single-degree-of-freedom (SDOF) and multi-degree-of-freedom (MDOF) systems. For that purpose, two sets of 20 earthquake ground motions representative of short-duration and long-duration records were considered in this investigation. While the influence of strong ground motion duration was evaluated through constant-strength residual displacement ratios, $C_r$, computed from the nonlinear response of elastoplastic SDOF systems, its effect on the amplitude and height-wise distribution of residual drift demands in MDOF systems was studied from the response of three one-bay two-dimensional generic frame models. In this investigation, an inelastic ground motion intensity measure was employed to scale each record, which allowed reducing the record-to-record variability in the estimation of residual drift demands. From the results obtained in this study, it was found that long strong-motion duration records might trigger larger median $C_r$ ratios for SDOF systems having short-to-medium period of vibration than short strong-motion duration records. However, taking into account the large record-to-record variability of $C_r$, it was found that strong motion duration might not be statistically significant for most of the combinations of period of vibration and levels of lateral strength considered in this study. In addition, strong motion duration does not have a significant influence on the amplitude of peak residual drift demands in MDOF systems, but records having long strong-motion duration tend to increase residual drift demands in the upper stories of long-period generic frames.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.153-162
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• 2017

PURPOSES : This study was conducted to analyze the effects arising from extending the duration of nighttime road construction on improving road quality and durability. METHODS : Most previous studies estimating the social cost of various construction conditions did not consider road pavement cooling time as a factor in improving road pavement quality. This study investigated the feasibility of achieving higher road quality and durability by extending the duration of nighttime road construction time extension. For this investigation, the effects of such an extension on traffic conditions were analyzed based on micro-simulation studies and scenario-based cost-benefit analyses, using factors including traffic volume, delay, construction cost, and road pavement cooling time. RESULTS : The results of the traffic simulation studies and cost-benefit analyses indicate that the current road construction method that emphasizes completing nighttime road construction by 6 a.m. reduces pavement life while causing relatively little traffic delay. If the night construction time is instead extended to 2 p.m., road pavement lifetime is increased, reducing road re-construction cost. These savings are greater than the cost of congestion arising from extending the duration of nighttime construction. CONCLUSIONS : The current nighttime construction durations need to be extended in order to efficiently manage roads and reduce road management costs.

• Journal of Bio-Environment Control
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• v.13 no.2
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• pp.67-72
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• 2004

Red peppers(Capsicum annuum L.), 'Geumtap' and 'Bugang', were cultivated at main producing areas in Korea, and harvested 4 times in 1998 and 1999. The relationships between internal qualities such as reducing sugar, capsaicinoids, and vitamin C contents, and regional climatic elements such as total accumulated air temperature, total amount of precipitation and sunshine duration during the fruit growing periods were compared. The amount of reducing sugar increased as the harvest time was late. Capsaicinoids content varied by harvest dates and cultivated years. Vitamin C content was influenced by cultivated year more than cultivars. Reducing sugar content showed a negative relationship with total amount of precipitation but showed a positive relationship with sunshine duration. There were negative relationship between the contents of capsaicinoids and vitamin C and total amount of precipitation.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.123-133
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• 1995

An injection control valve(ICV) was designed to control the fuel flow between a common rail and an injector with two commercial solenoids. To improve the performance of ICV, the characteristic method was applied. With this method, the flow characteristics in the ICV and the injector were studied and the parameters which affect the injection characteristics were also studied. From this study, following results were obtained. The injection duration can be controlled and with modifications of the effective valve stroke of ICV, the injection quantity and duration can be reduced to desired amount. Also the injection quantity and pressure can be controlled by reducing the hole size of the injector without the variation of the injection duration. For some conditions, the desired injection characteristics can be obtained by the changes of the valve timing, the effective valve stroke, the open pressure of the injector and the hole size of the injector.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.75-82
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• 2007

This paper proposes the way that reduces power consumption of the IEEE 802.15.4-based sensor network. To reduce power consumption, we consider following two schemes; first scheme is the Adaptive Beacon Interval Control. The next is the Adaptive Superframe Duration Control. Our results show that these guarantee reducing power consumption in ns-2 simulator.

• Korean Journal of Adult Nursing
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• v.26 no.1
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• pp.89-97
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• 2014

Purpose: During hospitalization, confusion occurs in 15~20% of older adults and persists in 5~10% of them. This study was designed to investigate effects of a five-day nursing intervention program designed to reduce confusion in hospitalized older adults. Subjects were inpatients over the age of 60 years old and were admitted in a surgical care unit. Methods: Data were collected from 111 patients. Subjects divided into one of two groups, 58 patients of the control group which received the usual nursing care; and 53 patients of the intervention group which received the usual nursing care plus nursing intervention program for reducing acute confusion. The Delirium Observation Screening Scale (DOS) and the Korean Mini-Mental Screening Examination (MMSE-K) were utilized. Results: 1) Acute delirium was significantly reduced in the intervention group compared to the control group ($x^2$=4.22, p=.034) as well as the duration of the delirious state was significantly shortened (F=56.62, p<.001). Cognitive function of the intervention group was improved (F=21.14, p<.001). Conclusion: The nursing intervention program reduced the incidence and duration of acute delirium of the elderly inpatients, as well as it helps them keep better cognitive function than the control group.