• Imaging Science in Dentistry
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• v.53 no.4
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• pp.313-323
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• 2023

Purpose: This study aimed to investigate the potential factors that could affect the reduction rate of odontogenic cysts following decompression using cone-beam computed tomography (CBCT) for 3-dimensional volumetric analysis. Materials and Methods: The study sample consisted of CBCT images of 41 individuals who underwent decompression of odontogenic cysts at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Chulalongkorn University, between 2010 and 2022. Preoperative and postoperative CBCT results were collected, and a volumetric analysis was conducted to evaluate the differences in the reduction rate and the percentage of volume reduction of cystic lesions based on different parameters. Correlations between these parameters were analyzed to determine associations. Results: In this study, the average time of decompression for odontogenic cysts was 316 days. Males demonstrated a higher reduction rate than females (P<0.05). The reduction rate was directly proportional to initial cyst volume, with higher reduction rates for cysts with large initial volume than those with small initial volume (P<0.05). Spearman's rank correlation coefficient indicated a weak positive correlation between the initial cyst volume and the duration of decompression. Additionally, a strong positive correlation was observed between the initial volume and the reduction rate. Conclusion: Knowledge of the reduction rate of odontogenic cysts is vital for surgeons to evaluate the duration of decompression before enucleation and to determine a definitive treatment plan. Sex and initial lesion volume had significant effects on the reduction rate.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.368-372
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• 2007

Recently, construction companies prefer to use large scale system forms to prepare for lacking of skilled workers, aging and the chances of application of pre-build&post-sale policy. In result of the effort and interest, the duration for framework of domestic high rise buildings has been accomplished to 3-4days per floor but for the apartment housing which form over 90% of the domestic construction industry, and especially the middle story RC apartments which is the main part, the duration for framework is only about 6-8days per level. This is only about 50% of the duration per level of RC residential buildings in North America. In previous researches elementary technology, which has potential of duration reduction, was proposed and this research suggest the applicability in construction sites and ways to improve it using elementary technology applied Mock-up Test. Furthermore, we analyze the productivity and T/C usage rate of the 6day-Cycle and suggest an improved model.

• Advances in pediatric surgery
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• v.16 no.2
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• pp.108-116
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• 2010

Air reduction is a safe, effective, and fast initial treatment for pediatric intussusception. There is low dose radiation exposure. Factors affecting outcomes of air reduction were analyzed by reviewing the clinical features and results of treatment. A total of 399 out of 485 patients with pediatric intussusceptions were treated at the Seoul National University Children's Hospital from 1996 to 2009. All of the patients received air reduction as the first line of treatment. Clinical features such as gender, age, seasonal variation, symptoms, signs, types, pathologic leading point, and treatment results including success rate, complication, recurrence, NPO time, and duration of hospitalization were reviewed. The Pearson chi-square, student T-, and logistic regression tests were used for statistical analysis. P-value less than 0.05 was considered to be statistically significant. The prevalent clinical features were: male (65.4 %), under one-year of age (40.3 %), ileocolic type (71.9 %), abdominal pain (85.4 %), and accompanying mesentery lymph node enlargement (2.2 %). The overall success rate for air reduction was 78.4 % (313 of 399 patients), and the perforation rate during reduction was 1.5 %. There were 23 recurrent cases over 21.6 months. All were successfully treated with re-do air reduction. Reduction failures had longer overall NPO times (27.067hrs vs. 43.0588hrs; p=0.000) and hospitalization durations (1.738d vs. 6.975d; p=0.000) compared to the successful cases. The factors affecting success rates were fever (p=0.002), abdominal distension (p=0.000), lethargy (p=0.000) and symptom duration (p=0.000) on univariate analysis. Failure rates were higher in patients with symptom durations greater than 24 hours (p=0.023), and lethargy (p=0.003) on multivariate analysis. Air reduction showed high success rates and excellent treatment outcomes as the initial treatment for pediatric intussusception in this study. Symptom duration and lethargy were significantly associated with reduced success rates.

• Korean Journal of Construction Engineering and Management
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• v.3 no.3 s.11
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• pp.84-93
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• 2002

It is important to reduce construction duration in private sales and lease business for management of cash now in the owner's aspect. However, because the concept of standard duration hasn't been established in the domestic construction industry, it is difficult to present the standard of duration estimate. To solve this problem, this paper (1) grasped the effecting elements considered in the duration estimate through referring the existing literature related to the schedule management, (2) accomplished a comprehensive research on actual duration based on office buildings through the questionnaire survey and the expert interview, (3) presented the collected research data analyzed by effecting elements as standard duration, (4) compared standard duration with actual duration of countries advanced in construction projects as well as analyzed them, and then (5) raised the necessity of duration reduction in the domestic construction industry.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.2
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• pp.97-104
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• 2015

Compared with a strong axial rigidity due to large intial tension, cable has a weak laterally flexural rigidity. A variety of dynamic loads such as traffic loads and wind loads etc. cause the cables to vibrate significantly and affect the mechanical properties and the performance of cables. Therefore, vibration reduction design is an urgent task to control the vibration of cable-supported bridges. Because a various kind of dampers have shown to reduce the amplitude and duration time of vibration of cable from measured date in field test, damper can be considered that it is effective device significantly to reduce the amplitude and duration time in vibration of cable. Vibration characteristics of cable can change according to manufacturing method and type of established form, and damper has been designed according to distribution of natural frequencies and vibration modes. In this study, numerical analysis is used to show the reduction effects of vibrations and present the design of damper for vibration reduction of cable.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.447-450
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• 2004

The domestic construction industry have focus on duration than construction cost. But recently it have interesting to The domestic construction industry, social requirement is changing. At the moderate speed duration has other angle of reducing cost and management of efficiency. specially Apartment building construction process is similar to other construction industry so it Is obtain a strong Point. This study on, A Target of construction industry is short duration than other it, general construction duration in summary schedule of level is studied, is based and construction duration for the point it is indicated reduction duration

• Phonetics and Speech Sciences
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• v.12 no.2
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• pp.9-16
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• 2020

The present study examines the degree of suffix reduction that occurs when the Korean suffix [-nɨn] was attached to the root in spontaneous Seoul Korean speech. Specifically, it focuses on the degrees of reduction produced by individual speakers. The degree of reduction was assessed as the duration of the suffix [-nɨn] to clarify the continuum between the full and reduced forms. The results revealed that, first, the reduced forms of the suffix [-nɨn] were significantly distinguished from the full forms in the suffixation processes. Second, regarding parts of speech, the differences among individual speakers on the degrees of reduction were clearer when the suffix [-nɨn] was attached to verbs, rather than nouns and pronouns. Finally, the length of a root played a critical role in determining the degree of reduction of the suffix [-nɨn]. The degrees of reduction for individual speakers significantly differed when the suffix [-nɨn] was attached to two-syllable roots than three- and four-syllable roots. In conclusion, individual differences in the degrees of reduction were likely to occur when the roots are verbs and when two-syllable roots.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.35-40
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• 2000

The influence of cyclic loading history on the creep behavior of the 30 vol% hot-pressed $SiC_f/Si_3N_4copmposite was experimentally investigated at $1200^{\circ}C$. The duration of loading/unloading had great effects on the creep behaviors. The short term duration cyclic loading history test results showed significant reduction in the primary and steady-state creep rates. For example, 300sec loading/300sec unloading history resulted in 70% lower steady-state creep rate than that of the continuous loading. However the long term duration cyclic loading history test results showed little change in creep rates compared to those of the continuous one. The reason for the significant change in the short term duration cycles was estimated due to the change in the stress redistribution between the fiber and matrix during the creep recovery in the primary stage.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.5
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• pp.89-98
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• 2004

The amount of rice yield reduction due to inundation should be estimated to analyse economic efficiency of the farmland drainage improvement projects because those projects are generally promoted to mitigate flood inundation damage to rice in Korea. Estimation of rice yield reduction will also provide information on the flood risk performance to farmers. This study presented the relationships between inundated durations and rice yield reduction rates for different rice growth stages from the observed data collected from 1966 to 2000 in Korea, and developed the rice yield reduction estimation model (RYREM). RYREM was applied to the test watershed for estimating the rice yield reduction rates and the amount of expected average annual rice yield reduction by the rainfalls with 48 hours duration, 10, 20, 50, 100, 200 years return periods.

• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.297-305
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• 2008

It is necessary to select proper reduction methods and to calculate reasonably reduction amount for making good practice of the reduction scheme. Moreover, it is suggested that the reduction amount have to be distributed properly during the planning period. In other words, it has not to be concentrated on the specific year (especially final year of the planning period). The reason why, if the reduction amount concentrate on the final year of the planning period, allotment loading amount could not be achieved in some cases (e.g., insufficiency of budget, extension of construction duration). Even though much of the budget have been supported from national treasury (about 50%), it is thought the role of the local government must be strengthened gradually.