• Journal of Environmental Science International
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• v.22 no.6
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• pp.779-785
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• 2013

To examine the psychological characteristics and work ethics of Hanwoo managers, we selected 26 of the 50 managers who took part in this study to avoid unreliable response and non-description from the questionnaire. The core results of this study were the following: First, cronbach's ${\alpha}$ reliability with highest domain in this study were obtained from character strengths (.938), followed by job satisfaction (.841), internal evaluation (.799), and external evaluation (.739). Second, for perception and attitude of Hanwoo management, the correlation between job satisfaction and internal evaluation (P<0.05) was observed. Management satisfaction showed higher for intermediate group and subgroup and lower satisfaction for the top group. Third, there were statistical differences (P<0.05) in ten character strengths (curiosity, judgment, creativity, social intelligence, wisdom, honesty, optimism, responsibility, humor, and passion) according to group satisfaction. Ten character strengths were lower in creativity (7.14) and higher in responsibility (8.57) in comparison with other items for the top group. In conclusion, these results suggest that character strengths are beneficial to improve Hanwoo management on psychological characteristics and work ethics of managers.

• Journal of Power Electronics
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• v.18 no.3
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• pp.863-870
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• 2018

The traditional power control theories for the harmonic reduction methods in multilevel inverters are found to be unreliable under unbalanced load conditions. The unreliability in harmonic mitigation is caused by voltage fluctuations, non-linear loads, the use of power switches, etc. In general, the harmonics are reduced by filters. However, such devices are an expensive way to provide a smooth and fast response to secure power systems during dynamic conditions. Hence, the Decoupled Double Synchronous Reference Frame (DDSRF) theory combined with a State Delay Controller (SDC) is proposed to achieve a harmonic reduction in power systems. The DDSRF produces a sinusoidal harmonic that is the opposite of the load harmonic. Then, it injects this harmonic into power systems, which reduces the effect of harmonics. The SDC is used to reduce the delay between the compensation time for power injection and the generation of a reference signal. The proposed technique has been simulated using MATLAB and its reliability has been verified experimentally under unbalanced conditions.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.4
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• pp.173-180
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• 2023

Purpose: Gastro esophageal reflux disease (GERD) is a burdensome disease affecting many children. A clinical examination is reported to be unreliable to diagnose GERD in children. This study aimed to investigate the relationship between the Pediatric Gastroesophageal Reflux Disease Symptom and Quality of Life Questionnaire (PGSQ) and endoscopic and histopathological findings in children with symptoms suggesting GERD. Changes in the PGSQ score in children with esophagitis as response to one month therapy were recorded as secondary outcome. Methods: This is a prospective cohort study in the pediatric outpatient clinic in an Indonesian tertiary hospital. Children aged 2-17 years old with clinical symptoms suspected of GERD are included in the study. Blinded endoscopic and histopathological examination was performed in all patients before one month proton pump inhibitors (PPI) therapy. The PGSQ information was collected at inclusion and after one month PPI treatment. Results: Fifty-eight subjects were included. Esophagitis was found in 60.9% of subjects according to endoscopy and 58.6% according to histology. There was no significant relationship between the PGSQ score and endoscopic (p=0.781) nor biopsy (p=0.740) examinations. The PGSQ showed a low diagnostic value compared to endoscopy and biopsy (area under the curve [AUC] 0.477, p=0.477, 95% confidence interval [CI] 0.326-0.629 and AUC 0.474, p=0.740 (95% CI 0.321-0.627 respectively). The PGSQ improved significantly post one month of PPI treatment. Conclusion: The PGSQ cannot be used to diagnose esophagitis in children with clinical symptoms suggesting GERD. However, the PGSQ can be used to monitor the treatment response in children with esophagitis.

• Physical Therapy Korea
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• v.19 no.3
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• pp.91-97
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• 2012

The primary aim of this study was to compare responsiveness of self-report by worker and therapist-scored functional capacity instrument. Self-report and therapist-scored interval-level person measures and item difficulties were compared at admission and discharge. Therapist and worker ratings were collected on 230 clients from 27 rehabilitation sites using the newly developed Occupational Rehabilitation Data Base (ORDB) functional capacity instrument. ORDB comprises several subscales measuring relevant variables of "a return-to-work model" in work-related rehabilitation clinics. The functional capacity scale deals with 10 DOT job factors. The rating scale categories were 1-severely impaired, 2-moderately impaired, 3-mildly impaired, and 4-not impaired. Only data from clients with low back pain (n=98) with complete data (both admission and discharge scores) were used for the present study. Therapists and workers completed the functional capacity instrument at admission and discharge. Rasch analysis [1-parameter item response theory model (IRT)] was applied to calibrate item difficulty and person ability measure of therapist and workers ratings. Effect sizes for therapist and self-report ratings were slightly different, .69 and .30, respectively. Therapist and worker ratings were more consistent at discharge (r=.54) than at admission (r=.32). Workers have a tendency to be more severe in their ratings (show higher item difficulties) than therapists at admission and discharge. Therapists and workers report similar magnitudes of improvement following treatment program. These findings challenge the belief that injured workers may unreliable source for monitoring therapeutic outcomes. Self-report measures have the advantage of conserving therapist time for treatment (versus evaluation). While the therapist and self-report ratings are comparable at discharge, there is less consistency at admission. Comparable therapist-worker ratings may be achieved by controlling for rating severity using IRT methodologies.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.3
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• pp.423-431
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• 2011

Warfighting experimentation is an important process for identifying requirements against changing military environment and for verifying proposed measures for reforming military service. The wargame simulation experiment is regarded as one of the most effective means to warfighting experimentation, and its importance is increasing than ever. On the other hand, the results of wargame experiments could be unreliable due to the uncertainty involved in the experimental procedure. To improve the reliability of the experimental results, systematic experimental procedures and analysis methods must be employed, and the design and analysis of experiments technique can be used effectively for this purpose. In this paper, AWAM, a wargame simulator, is used to optimize the organization of operational troops. The simulation model describes a warfighting situation in which the 'survival rate of our force' and the 'survival rate of the enemy force' are considered as responses, 'the numbers of weapons in the squad' as control factors, and 'the uncontrollable variables of the battlefield' as noise factors. In addition, for the purpose of effective experimentation, the product array approach in which the inner and outer orthogonal arrays are crossed is adopted. Then, the signal-to-noise-ratio for each response and the desirabilities for the means and standard deviations of responses are calculated and used to determine a compromise optimal solution. The experimental procedures and analysis methods developed in this paper can provide guidelines for designing and analyzing wargame simulation experiments for similar warfighting situations.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.467-467
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• 2015

Sustainable water resource management requires the assessment of hydrological variability in response to climate fluctuations and anthropogenic activities. Determining quantitative estimates of water balance and total basin discharge are of utmost importance to understand the variations within a basin. Hard-to-reach areas with few infrastructures, coupled with lengthy administrative procedures makes in-situ data collection and water management processes very difficult and unreliable. In this study, the hydrological behavior of Lake Chad whose extent, extreme climatic and environmental conditions make it difficult to collect field observations was examined. During a 10 year period [January 2003 to December 2013], dataset from space-borne and global hydrological models observations were analyzed. Terrestial water storage (TWS) data retrieved from Gravity Recovery and Climate Experiment (GRACE), lake level variations from Satellite altimetry, water fluxes and soil moisture from Global Land Data Assimilation System (GLDAS) were used for this study. Furthermore, we combined altimetry lake volume with TWS over the lake drainage basin to estimate groundwater and soil moisture variations. This will be validated with groundwater estimates from WaterGAP Global Hydrology Model (WGHM) outputs. TWS showed similar variation patterns Lake water level as expected. The TWS in the basin area is governed by the lake's surface water. As expected, rainfall from GLDAS precedes GRACE TWS with a phase lag of about 1 month. Estimates of groundwater and soil moisture content volume changes derived by combining altimetric Lake Volume with TWS over the drainage basin are ongoing. Results obtained shall be compared with WaterGap Hydrology Model (WGHM) groundwater estimate outputs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1A
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• pp.45-52
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• 2009

In conventional structural design, deterministic optimization which satisfies codified constraints is performed to ensure safety and maximize economical efficiency. However, uncertainties are inevitable due to the stochastic nature of structural materials and applied loads. Thus, deterministic optimization without considering these uncertainties could lead to unreliable design. Recently, there has been much research in reliability-based design optimization (RBDO) taking into consideration both the reliability and optimization. RBDO involves the evaluation of probabilistic constraint that can be estimated using the RIA (Reliability Index Approach) and the PMA(Performance Measure Approach). It is generally known that PMA is more stable and efficient than RIA. Despite the significant advancement in PMA, RBDO still requires large computation time for large-scale applications. In this paper, A new reliability-based design optimization (RBDO) method is presented to achieve the more stable and efficient algorithm. The idea of the new method is to integrate a response surface method (RSM) with PMA. For the approximation of a limit state equation, the moving least squares (MLS) method is used. Through a mathematical example and ten-bar truss problem, the proposed method shows better convergence and efficiency than other approaches.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.10
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• pp.429-436
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• 2017

There is a growing tendency to outsource sensitive or important data in cloud computing recently. However, it is very important to protect the privacy of outsourced data. So far, a variety of secure and efficient multi-keyword search schemes have been proposed in cloud computing environment composed of a single data owner and multiple data users. Zhang et. al recently proposed a search protocol based on multi-keyword in cloud computing composed of multiple data owners and data users but their protocol has two problems. One is that the cloud server can illegally infer the relevance between data files by going through the keyword index and user's trapdoor, and the other is that the response for the user's request is delayed because the cloud server has to execute complicated operations as many times as the size of the keyword index. In this paper, we propose an improved multi-keyword based search protocol which protects the privacy of outsourced data under the assumption that the cloud server is completely unreliable. And our experiments show that the proposed protocol is more secure in terms of relevance inference between the data files and has higher efficiency in terms of processing time than Zhang's one.

• Industry Promotion Research
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• v.8 no.2
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• pp.133-140
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• 2023

The purpose of the study is to verify the mediating effect of positive automatic thinking in the relationship between stress coping and psychological well-being in middle age. For this study, a survey was conducted on middle-aged people under the age of 40 to 65 living in Seoul, Gyeonggi-do, and Incheon. A total of 200 questionnaires were distributed from March 9 to March 27, 2023, and 187 questionnaires were used for the final analysis, except for 13 copies whose responses were judged to be poor or unreliable. Correlation, factor analysis, and structural equation models were conducted, and bootstrapping was analyzed to verify the mediating effect. As a result of the analysis, it was confirmed that coping with stress in middle age affects psychological well-being. As a result of analyzing the influence of problem-solving-oriented, social support-oriented, and avoidance-oriented as sub-factors of coping with stress, it was found to have a significant effect on psychological well-being. Stress coping has been shown to have a direct effect on psychological well-being and increase psychological well-being through the parameters of positive automatic thinking. consequently within the individual of coping with stress in middle age.It is expected that the buffering effect of external factors and positive automatic thinking will improve psychological well-being in middle age and achieve positive results.

• Journal of Environmental Science International
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• v.3 no.3
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• pp.273-284
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• 1994

The primary objective of this study was to examine the toxic effects of PCP on activated sludge and to analyze its metabolic responses while treating wastewater containing pentachlorophenol (PCP) in a sequencing batch reactor (SBR) system operating under different control strategies. This study was conducted in two phases 1 and 2 (8-hr and 12-hr cycles). Each phase was operated with two control strategies I and II. Strategy I (reactor 1) involved rapid addition (5 minutes to complete) of substrate to the reactor with continuous mixing but no aeration for 2 hours. Strategy ll (reactor 2) involved adding the feed continuously during the first 2 hours of the cycle when the system was mixed but not aerated. During both phases each reactor was operated at a sludge age of 15 days. The synthetic wastewater was used as a feed. The COD of the feed solution was about 380 mg/l. After the reference response for both reactors was established, the steady state response of each system was established for PCP feed concentrations of 0.1 mg/l, 1.0 mg/l, and 5.0 mg/l in SBR systems operating on both 8-hr and 12-hr cycles. Soluble COD removal was not inhibited at any feed PCP concentrations used. At 5.0 mg/l fined PCP concentration and in SBR systems operating on phase 2, the concentrations of MLVSS were decreased; selective pressure on the mixed biomass might be increased, narrowing the range of possible ecological responses; the settleability of activated sludge was poor; the SOURS were increased, showing that the systems were shocked. Nitrification was made to some extent at all concentrations of feed PCP in SBR systems operating on phase 2 whereas in SBR systems operating on phase 1 little nitrification was observed. Then, nitrification will be delayed as much as soluble COD removal is retarded due to PCP inhibition effects. Enhanced biological phosphorus removal occurring in the system operating with control strategy I during phase 1 of this work and in the presence of low concentrations of PCP was unreliable and might cease at anytime, whereas enhanced biological phosphorus removal occurring in the system operating with either control strategy I or II during phase 2 of this work and in the Presence of feed PCP concentrations up to 1.0 mg/l was reliable. When, however, such processes were exposed to 5.0 mg/l PCP dose, enhanced phosphorus removal ceased and never returned.