Earticle

The distribution of power supplies be obliged to offer reliable, superior-quality in power. To obtain good power quality the transmission line faults identification should bemore precise, consistence and complete rectification is required. The faults in the transmission and distribution lines influence the power quality. The major faults in transmission lines such as line to ground fault, line-to-line fault and three-phase faults. This paper proposes a unique organized interrelated structure for fault-location and classification technique for transmission lines through an experimental set-up similar to transmission and distribution for good power quality. The proposed method utilizes synchrophasor measurements during the disturbances from the transmission lines and compares with idealcondition signals for fault location and classification. From the results, the synchrophasor measurements identifies faults in the initial stage. The phasor measurement results are modelled through regression modelling for precise measurement. Various faults are modelled for the earlier detection in the transmission lines.

Objective To determine the abnormal pulmonary function value in Korean Duchenne muscular dystrophy (DMD) patients, we performed a comparative analysis of the patients’ pulmonary function value expressed as % of the overseas reference data and Korean healthy children and adolescent reference data.Methods We performed pulmonary function test (PFT) in a total of 27 DMD patients. We compared the patients’ FVC% and FEV1% of the overseas reference data with those of the Korean children and adolescent reference data. Also, we compared the patients’ MIP% and MEP% of the prediction equation data with those of the Korean children and adolescent reference data. Results Age of the subjects ranged from 8 to 16 years (12.03±2.27 years). The mean maximal expiratory pressure (MEP), maximal inspiratory pressure (MIP), vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and peak cough flow (PCF) were 36.93±9.5 cmH2O, 45.79±17.46 cmH2O, 1.4±0.43 L, 1.45±0.45 L, 1.40±0.41 L, and 206.25±61.21 L/min, respectively. The MIP%, MEP%, and FVC% of the Korean children and adolescent reference data showed statistically significant higher values than those of the prediction equation data.Conclusion We observed a clear numeric difference between Korean DMD patients’ pulmonary function value expressed as % of the overseas data and inland data. To perform a precise assessment of respiratory function and to determine appropriate respiratory therapy, pulmonary function values of Korean DMD patients should be interpreted taking into account the inland normal pulmonary function test data.

Purpose: This study was conducted to obtain data for the development of an effective fall risk assessment tool for pediatric inpatients through a systematic review and meta-analysis of the diagnostic test accuracy of existing scales. Methods: A literature search using Medline, Science Direct, CINAHL, EMBASE, and the Cochrane Library was performed between March 1 and 31, 2018. Of 890 identified papers, 10 were selected for review. Nine were used in the meta-analysis. Stata version 14.0 was used to create forest plots of sensitivity and specificity. A summary receiver operating characteristic curve was used to compare all diagnostic test accuracies. Results: Four studies used the Humpty Dumpty Falls Scale. The most common items included the patient's diagnoses, use of sedative medications, and mobility. The pooled sensitivity and specificity of the nine studies were .79 and .36, respectively. Conclusion: Considering the low specificity of the pediatric fall risk assessment scales currently available, there is a need to subdivide scoring categories and to minimize items that are evaluated using nurses' subjective judgment alone. Fall risk assessment scales should be incorporated into the electronic medical record system and an automated scoring system should be developed.

Objective To investigate the postural control factors influencing the automatic (reflex-controlled) and attentional (high cortical) factors on dual task.Methods We used a dual task model to examine the attentional factors affecting the control of posture, subjecting test subjects to vibration stimulation, one-leg standing and verbal or nonverbal task trials. Twenty-three young, healthy participants were asked to stand on force plates and their centers of pressure were measured during dual task trials. We acquired 15 seconds of data for each volunteer during six dual task trials involving varying task combinations.Results We observed significantly different sway patterns between the early and late phases of dual task trials, which probably reflect the attentional demands. Vibration stimulation perturbed sway more during the early than the late phases; with or without vibration stimulation, the addition of secondary tasks decreased sway in all phases, and greater decreases in sway were observed in the late phases, when subjects were assigned nonverbal tasks. Less sway was observed during the nonverbal task in a sequential study.Conclusion The attentional and automatic factors were analyzed during a sequential study. By controlling the postural control factors, optimal parameters and training methods might be used in clinical applications.

Numerical study on a lifting system developed for shallow sea test is performed by a CFD model. In this study, the flow behaviors in a lifting pump and flexible hoses is simulated by using FLUENT, a commercial CFD model. Two cases for calculation the pump cavitation behavior are selected according to the hose length and the depth of lifting pump. From the numerical results, it is found that the vortex flow is observed in the first-stage stator and the calculated NPSH meets the minimum required by a lifting pump based on the shallow sea environments.

Background Wearable gait analysis devices are increasingly used in clinical practice to evaluate spatiotemporal gait parameters. StepLab is one such device; however, research on its reliability for gait analysis remains limited. Purpose This study aimed to evaluate the test?retest reliability of spatiotemporal gait parameters measured using the StepLab IMU-based wearable device in healthy young adults. Study design Cross-sectional study Methods Forty healthy participants (20 females and 20 males; mean age 21.7±3.44 years) completed three 10-meter walk trials at a comfortable, self-selected pace. The same protocol was repeated one week later to assess measurement consistency. Gait parameters, including gait speed, swing duration, stance duration, cycle time, cadence, stride length, and step length, were analyzed. Test?retest reliability was determined using intraclass correlation coefficients (ICC 3,2). Bland?Altman analysis and standard error of measurement (SEM) were additionally calculated. Results All spatiotemporal gait parameters demonstrated good to excellent test?retest reliability, with ICC values ranging from 0.84 to 0.99 and small SEM estimates across variables. Bland?Altman analysis revealed minimal mean differences and narrow limits of agreement, indicating high measurement consistency between sessions. Conclusions The StepLab device demonstrated good to excellent test?retest reliability for spatiotemporal gait parameters in healthy young adults under controlled indoor conditions. However, caution is warranted when interpreting these findings due to the homogeneous sample and the short 10-meter walking distance. Future studies should examine reliability in clinical and elderly populations, assess longer walking tasks, and validate StepLab against gold-standard gait analysis systems before broader clinical application.

Nowadays more and more applications rely on the information provided by Global Navigation Satellite Systems (GNSSs), but the vulnerability of GNSS signals to interference, jamming and spoofing is a growing concern. Among all the possible sources of intentional interference, spoofing is extremely deceptive and sinister. In fact, the victim receiver may not be able to warn the user and discern between authentic and false signals. For this reason, a receiver featuring spoofing detection capabilities might become a need in many cases. Different types of spoofing detection algorithms have been presented in recent literature. One of the first, referred to as Ratio Metric, allows for the monitoring of possible distortions in the signal correlation. The effectiveness of the Ratio Test has been widely discussed and demonstrated, while in this paper we analyze its performance, proposing a mathematical model that is used to assess the false alarm and detection probabilities.

Purpose: This study was conducted to estimate the prevalence of questionable development according to developmental screening testing for children, and to explore biological and environmental risk factors of developmental delays. Method: The study participants were 153 children under two years of age. A questionnaire and Home Observation for measurement of the Environment (HOME) inventory were used to collect data, and Korean Denver II was administered. Results: The overall prevalence of questionable development was 11.1%. Significant differences in biological factors between the normal development group and questionable development group were the rate of prematurity, twins, the educational level of mother and father's and the presence of an illness in the mother (p<.10). Maternal acceptance in HOME was significantly different between the two groups. The factors related to questionable development that were significant in the logistic regression analysis were prematurity (OR=3.56, p=.026), and maternal acceptance in HOME score (OR=.629, p=.028). Conclusion: Early developmental screening tests seem necessary for all children, especially for prematurely born children. Also, child rearing environments were identified as significant factors in the development of all children. These findings suggest that the HOME scores might be useful in identifying children at risk for developmental delays, and that interventions for these children will probably be more effective if their mothers are helped to provide a more appropriate social environment.

Purpose To test the impact of interpersonal caring theory empirically on six major psychosocial functioning outcomes of persons with serious mental illness. Methods This was a quasi-experimental pre- and post-test design with data collection from a total of 266 patients with long-term serious mental illness, who were diagnosed with schizophrenia spectrum disorder and followed at 6-month intervals over a 24-month period in three groups: a community psychiatric service group, a community service with interpersonal caring intervention group, and a control group. Three hypotheses between the intensity, specificity, and longitudinality of services were tested using growth curve analysis. Results Hierarchical linear modeling supported associations of hypotheses between the intensity, specificity, and longitudinality of services and improved patient outcomes. Conclusion This study suggests that the intensity, specificity, and longitudinality of interpersonal caring interventions in community psychiatric service programs deserve attention in order to improve and maintain patient functional outcomes.

근해역 채광시험을 위해 제작된 양광펌프의 성능을 검증하고 곡관을 포함하는 유연관내 고-액 혼합물의 유동특성을 파악하기 위한 고-액 2상류 유동실험을 수행하였다. 총 양정 55 m의 양광펌프는 원심펌프로서 펌프의 상하단에는 유연관이 연결된다. 실험에 사용된 유연관은 해양채광에 적합하도록 직경 100 mm, 단위길이 10 m로 제작되었다. 실험결과 20%의 고체체적점유율까지 양광실험에 무리가 없는 것으로 확인하였으며 기존에 개발된 전산모델의 예측이 실험결과와 유사함을 확인하였다.Introduction

The flow characteristics of solid-liquid two-phase mixtures in a flexible hose are investigated using the experiments. Also the performance of the lifting pump for the offshore mining test are estimated. This centrifugal pump with the total head of 55 m is for lifting the minerals on the seabed. The inlet of this pump is connected to the flexible hose, which is attached to the miner collector. The flexible hose is specially manufactured for the use in mining test with 100 mm in diameter. The results show the performance of the lifting pump is good for the offshore test.

This study investigated the test scores and student responses about placement in the General Education English Program by level and major. Using composite scores of College Scholastic Ability Test for English (CSAT) and the in-house speaking test (SEPT), the study placed students into four levels (2–5). It also categorized 1,847 students into three groups: Humanities and Social Science (HS), Business Administration and Law (BL), and Science and Engineering (SE). Higher levels showed significant differences in oral proficiency while having similar results on the CSAT. Lower levels attained similar scores on the SEPT but represented a vast range of CSAT scores. Participants across all levels understood the purpose of the placement test, perceived the content of the SEPT as appropriate, and positively responded toward the accuracy of placement. HS and BL scored higher on the test than SE, confirming the contrast between engineering and non-engineering majors. HS, however, showed more positive evaluation on the accuracy of placement than BL and SE. Across groups and levels, all participants opposed exclusively using CSAT in course placement. This study discusses utilizing data by various variables to enhance differentiated instruction and to meet unique needs of students at all levels with different majors; it also addresses using CSAT scores as the exclusive criterion.

강우량은 홍수 예방 및 가뭄 관리를 비롯한 수자원의 효과적인 관리를 위해 무엇보다 중요하다. 더욱이 기후변화의 영향으로 장래 수자원의 변동은 인간 생활에 매우 심각한 영향을 미칠 것으로 예측되고 있다. 본 연구에서는 안동댐 유역에 대한 42년간(1977~2018년)의 연강우량, 월강우량 및 월 최대강우량에 대한 경향분석을 실시하였다. 통계방법에는 모수적 검정과 비모수적 검정이 있다. 강우량과 같이 특정 확률분포를 따른다고 전제할 수 없는 경우 비모수적 검정을 사용한다. 따라서 본 연구에서는 비모수적 방법 중 강우량 추세분석을 위해 널리 사용되는 Mann-Kendall 검정 방법을 사용하였다. Mann-Kendall 검정 결과 유의수준 5%(0.05) 이내로 10월강우량과 7월 최대강우량은 증 가경향이 확인되었다. 또한 유의수준 10% 이내에서 8월 최대강우량은 감소하는 것으로 분석되었다. 본 연구의 결과는 특정 유역에서 발생하는 물부족과 홍수관리를 비롯한 수자원관리의 장기적 계획 을 수립하고자 할 때 매우 유용할 것으로 생각된다.

Rainfall has become a primary concern for flood control and effective water resources management. It is predicted that the reduction of available water resources due to climate change will exert a severe influence on human life. This study conducted a trend analysis on the annual rainfall, monthly rainfall, and monthly maximum rainfall at Andong Dam basin for 42 years from 1977 to 2018. Statistical hypothesis tests were performed by a nonparametric test because the rainfall data do not follow a particular probability distribution. This study utilized the Mann-Kendall test, one of the commonly used nonparametric testing methods, in order to analyze the rainfall trend variations. It is confirmed that the October rainfall and July maximum rainfall show an increasing trend according to the 5% confidence level. In addition, the August maximum rainfall reveals a decreasing trend according to the 10% confidence level.

본 연구에서는 강우침투특성을 규명하기 위해 모암의 성질이 다른 풍화토를 대상으로 침투모형시험 과 수치해석을 실시하여 풍화토별 간극수압 변화와 강우강도에 따른 간급수압 변화양상을 분석하였 다. 침투모형시험 장치는 자체 제작한 1차원 침투모형시험장비를 이용하였으며, 수치해석은 침투모 형시험장비와 동일한 실내시험 조건 및 경계조건으로 모델링하여 분석하였다. 모형시험 및 수치해 석 결과 동일한 강우강도를 적용한 결과 습윤전선이 컬럼하부에 도달하는 시간차는 유사하게 나타 났으며, 투수계수가 크면 침투능 또한 높게 나온다는 사실을 파악할 수 있었다, 또한 강우강도변화에 따라 습윤전선의 진행이 빠르게 진행됨을 파악할 수 있었다. 이러한 분석결과를 통해 지반의 투수계 수, 강우강도와 지속시간은 지반의 침투과정에 영향을 주는 주요 인자임을 확인할 수 있었다. 이러한 침투 메커니즘은 사면 안정해석에 적용되며, 지반의 액상화(지진)에 의한 위험도 평가에 응용될 수 있다.

This study conducted a rainfall infiltration test for weathered soils of different parent rocks in order to investigate infiltration characteristics. The changing pattern of pore water pressure was identified and compared with the numerical analysis results to analyze ground infiltration characteristics in relation to rainfall characteristics. The results of rainfall infiltration test and numerical analysis showed that the infiltration capacity became higher when the infiltration coefficient of weathered soil was large given that the same rainfall intensity was applied. Additionally, it was found that the movement of wetting front was fast in accordance with the changing rainfall intensity. The analysis results indicated that ground infiltration coefficient, rainfall intensity and duration were the major factors influencing ground infiltration process.

This study replicates and extends Lee-Ellis’s (2009) work by examining how different scoring methods affect the measurement characteristics of a Korean C-test. Thirty-six learners of Korean as a second language completed a five-passage C-test. Their responses were scored using Partial Credit Modeling, dichotomous item-by-item scoring, and dichotomous morpheme- by-morpheme scoring. Rasch analysis was conducted to compare reliability, person separation, item fit, and interpretability across these scoring approaches. The study also treated each text passage as a “super-item” to evaluate proficiency interpretation at the passage level. All three scoring methods demonstrated high reliability (above .97) and yielded highly correlated proficiency estimates. No single scoring method proved significantly superior in reliability, separation, or model fit. At the super-item level, the passages showed a narrow spread of difficulty indicating limited coverage of proficiency levels. These findings suggest that fine-grained scoring alone cannot compensate for limited test scope. To enhance the diagnostic value and level-referenced interpretation of C-tests, careful selection of text passages spanning a broader proficiency spectrum is essential.

Game development costs a lot of money. Thus, in terms of cost-saving, game companies produce prototypes and undergo several tests and modifications during the development period. In this paper, we proposed a brainwave signal analysis system and linked it with the game to measure the player's emotion through brainwave analysis experiment and tried to solve these problems. The brainwave signal analysis system proposed in this paper is capable of various applications according to various development situations, such as the progress of the game, events, etc. in obtaining simple figures over time by linking games, and collecting the tester's responses according to development intentions, so there will have to be continuous additional research.

Carton clamp truck is widely perceived as the high-efficient handling equipment of factory premises and warehouse by its capability of palletless handling. Therefore, the significance of a lab- based handling simulation is becoming higher with the growth of clamp truck usage. In this study, preliminary FEA and design of handling test courses for the lab-based simulation of carton clamp truck handling were performed, and the PSD analyses were performed for the modified one for the test course proposed by Park et al. (2017) as well as ASTM D 6055 and ISTA 3B standards. For the vibration in all directions, the vibration energy intensity analyzed by ISTA 3B standard showed higher than that by the other two cases. A FEA was performed for the handling operation of the sudden stop of the clamps after lifting the target HCP (heavyweight refrigerator corrugated package, w=180 kgf) up to the specified height. The slip distance between the clamp arm and the target HCP was 0.85 mm. The simulation result of 0.85 mm was 3.7 times lower than the experimental result (3.2 mm) obtained by Park et al. (2017), and it was estimated that the deviation comes from both the experimental error by weight imbalance of target HCP, and excessive simplification during the FE modelling of target HCP.

The purpose of this study is to analyze College Scholastic Ability Test items based on the Rasch Model, identify items that do not fit, and describe difficulty levels compared to student levels. Winsteps software, which allows users to analyze dichotomous data for investigating problems that are inherent in test items, is used for statistical analysis. The findings of this study reveal that 7 out of 28 items do not follow the assumptions of the Rasch Model. The analysis of item difficulty and item map shows that most of the 387 subjects are unable to answer some item types appropriately due to ambiguous distractors that affect item validity. Given the presence of misfit items and items of extreme levels of difficulty, suggestions for eliminating ambiguity, improving readability, and maintaining the degree of difficulty in designing reading test items are made.

Extending the conventional item response theory(IRT) as a measurement model to explanatory IRT(EIRT) based on generalized (non)linear mixed modeling has opened a new possibility to incorporate many item and person properties in its modeling process so that their effects can be considered simultaneously. The purpose of the current study was to apply EIRT to a complex data set that consisted of a reading comprehension test, a student survey of English study, and information about the item categories of the reading test. Sequential EIRT modeling of the data set showed that some of the item and person properties consistently had significant effects on the item difficulty and on the probability of correct answers. The modeling process also revealed some statistical or computational challenges researchers might encounter when they try to apply EIRT to complex language test data.