• Journal of Bio-Environment Control
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• 제29권4호
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1907-1912
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• 2015

Purpose: The study was designed to: (1) investigate the prevalence of high-risk human papillomavirus (HR-HPV) infection and cervical neoplasia; and (2) evaluate clinical performance of visual inspection with acetic acid/ Lugol's iodine (VIA /VILI), Pap smear, high-risk human papillomavirus (HR-HPV) DNA test for detecting cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and (3) explore appropriate screening approach in rural areas of Shandong Province. Materials and Methods: A total of 3,763 eligible women from Yiyuan County in Yimeng mountainous areas of rural Shandong, China, were enrolled and underwent Pap smear, HR-HPV DNA testing by Hybrid Capture 2 (HC2), and VIA /VILI tests. Women positive in any test were referred to colposcopy and biopsy as indicated. Results: The prevalence of HR-HPV infection among all enrolled women was 11.1% and that in healthy women was 9.9%. In total 33 cases of CIN1, 16 cases of CIN2, 6 cases of CIN3 but none of cervical cancer were detected and the crude prevalence of CIN2+ was 0.58%. For detecting CIN2+, the sensitivity of HR-HPV DNA testing, VIA/VILI, Pap smear was 90.9%, 77.3%, 81.8%, respectively. Pap smear had the best specificity of 98.2%, followed by HR-HPV DNA testing with specificity of 89.4%, VIA/VILI had the lowest specificity of 81.2%. Colposcopy referral rate of HR-HPV DNA testing, VIA/VILI, Pap smear was 11.1%, 18.5%, 2.3%, respectively. Conclusions: Our results suggest that HR-HPV DNA testing alone might be appropriate for primary cervical cancer screening in rural low-resource areas of Shandong Province, China.

• The Korean Journal of Franchise Management
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• 제10권2호
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• pp.49-58
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• 2019

Purpose - As the growth potential of the cultural contents industry steadily grows, the cinemas industry is growing fast especially due to popularity and commerciality. The recent in the cinemas industry is evolving on multiplex cinemas that combine cultural facilities such as theaters, restaurants, and shopping centers. Due to the rapid growth of multiplex cinemas, many researchers have studied the characteristics of visiting customers in Korea. Among them, selection attribute of multiplex cinemas, including the service quality and physical environment, is important because it may examines the cause of customer 's behavior. Thus, this research focuses on the effects of the selection attributes of the multiplex cinemas on customer satisfaction and their loyalty. This research suggests the guidelines for how cinemas should manage their customers and build their customers satisfaction and loyalty that improve business performance. Research design, data, and methodology - This study tests the structural relationship between selection attributes of multiplex cinemas, customer satisfaction, and loyalty. selection attributes of multiplex cinemas divide into five sub-dimensions such as movies facility quality, services, cleanliness, accessibility, and snack bars quality. In order to examine the purposes of this research, research model and hypotheses were developed. All constructs were measured with multiple items developed and tested in the previous studies. The data were collected from 100 students in their 10-20s and were analyzed using SPSS 22.0, SmartPLS 3.0 and fsQCA program. Result - The findings of this research are as follows. First, all selection attributes except cleanliness have significant positive impacts on customer satisfaction and loyalty. Second, customer satisfaction has significant positive impact on loyalty. Third, as a result of fsQCA, high satisfaction and high accessibility were the necessary conditions on loyalty. Fourth, the necessary conditions for male and female groups were different. Conclusions - The implications of this study are as follows. Overall, multiplex cinemas should manage selection attributes basically regardless of the type of theater. Especially, cleanliness was not significant, but the customer probably consider it an essential and basic factors. Also, they are able to manage the selection attributes differently depending on the type of gender. For the male customers, it is effective that centralized strategy and for female customers, it is effective that emphasized the multiplex cinemas image.

• Korean Journal of Radiology
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• 제24권10호
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• pp.1028-1037
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• 2023

Objective: To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. Materials and Methods: A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. Results: The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593-14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719-65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07-420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%-100%) and positive predictive value (PPV) (91.8%-100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. Conclusion: Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제24권4호
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• pp.220-227
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• 2013

Objectives : This study aims to investigate the clinical characteristics and neuropsychological profiles of children with attention-deficit hyperactivity disorder (ADHD) and their siblings. Methods : Eighteen children (age $8.2{\pm}1.7$ years, 12 boys) with ADHD and their 18 siblings (age $7.8{\pm}1.6$ years, 8 boys) completed Continuous Performance (CPT), Stroop, Children's Trail Making, Rey-Kim Memory, and Kim's Frontal Executive Function tasks. The parents of these subjects underwent the Attention-Deficit/Hyperactivity Disorder Rating Scale (ARS), 10-item Parent General Behavior Inventory (P-GBI), and the Social Responsiveness Scale (SRS). Paired t-tests were used. Results : The inattention (p=.020), and hyperactivity-impulsivity (p=.001), scores of the ARS and the P-GBI score (p=.004) were significantly higher in children with ADHD than in their siblings. Deficits in social communication and motivation on SRS were higher in children with ADHD than in their siblings (p=.017 and p=.011, respectively). Z-scores of omission and commission errors as well as response time variability on visual CPT and omission errors on auditory CPT were in clinically significant range, and z-score of omission errors on auditory CPT was in borderline range in siblings. Omission (p=.018) and commission errors on Visual CPT (p=.007) were significantly higher in children with ADHD compared to their siblings. Recognition efficiency on Kim's Frontal Executive Function Task was lower in children with ADHD compared to their siblings, but in normal range in both groups. Stroop interference and figure fluency on Kims Frontal Executive Function Task were in borderline range in ADHD group, and figure fluency was in borderline range in siblings. Conclusion : Our results support a preliminary evidence for mild degree of attention deficit in ADHD siblings. Further studies are needed to examine the cognitive functions of siblings with ADHD in larger samples.

• Journal of Korean Tunnelling and Underground Space Association
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• 제24권6호
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• pp.451-464
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• 2022

The high-level nuclear waste repository is a deep geological disposal system exposed to complex environmental conditions such as high temperature, radiation, and ground-water due to handling spent nuclear fuel. Continuous exposure can lead to cracking and deterioration of the structure over time. On the other hand, the high-level nuclear waste repository requires an ultra-long life expectancy. Thus long-term structural health monitoring is essential. Various sensors such as an accelerometer, earth pressure gauge, and displacement meter can be used to monitor the health of a structure, and a piezoelectric sensor is generally used. Therefore, it is necessary to develop a highly durable sensor based on the durability assessment of the piezoelectric sensor. This study designed an accelerated life test for durability assessment and life prediction of the piezoelectric sensor. Based on the literature review, the number of accelerated stress levels for a single stress factor, and the number of samples for each level were selected. The failure mode and mechanism of the piezoelectric sensor that can occur in the environmental conditions of the high-level waste repository were analyzed. In addition, two methods were proposed to investigate the maximum harsh condition for the temperature stress factor. The reliable operating limit of the piezoelectric sensor was derived, and a reasonable accelerated stress level was set for the accelerated life test. The suggested methods contain economical and practical ideas and can be widely used in designing accelerated life tests of piezoelectric sensors.

• Korean Journal of Materials Research
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• 제25권8호
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• pp.391-397
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• 2015

NiO catalysts/$Al_2O_3$/FeCrAl alloy foam for hydrogen production was prepared using atomic layer deposition (ALD) and subsequent dip-coating methods. FeCrAl alloy foam and $Al_2O_3$ inter-layer were used as catalyst supports. To improve the dispersion and stability of NiO catalysts, an $Al_2O_3$ inter-layer was introduced and their thickness was systematically controlled to 0, 20, 50 and 80 nm using an ALD technique. The structural, chemical bonding and morphological properties (including dispersion) of the NiO catalysts/$Al_2O_3$/FeCrAl alloy foam were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy and scanning electron microscopy-energy dispersive spectroscopy. In particular, to evaluate the stability of the NiO catalysts grown on $Al_2O_3$/FeCrAl alloy foam, chronoamperometry tests were performed and then the ingredient amounts of electrolytes were analyzed via inductively coupled plasma spectrometer. We found that the introduction of $Al_2O_3$ inter-layer improved the dispersion and stability of the NiO catalysts on the supports. Thus, when an $Al_2O_3$ inter-layer with a 80 nm thickness was grown between the FeCrAl alloy foam and the NiO catalysts, it indicated improved dispersion and stability of the NiO catalysts compared to the other samples. The performance improvement can be explained by optimum thickness of $Al_2O_3$ inter-layer resulting from the role of a passivation layer.

• Tunnel and Underground Space
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• 제33권5호
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• pp.348-372
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• 2023

In relation to the high-level radioactive waste disposal project in deep fractured rock aquifer environments, it is essential to evaluate hydrogeological characteristics for evaluating the suitability of the site and operational stability. Such subsurface hydrogeological data is obtained through in-situ tests using boreholes excavated at the target site. The accuracy and reliability of the investigation results are directly related to the selection of appropriate test methods, the performance of the investigation system, standardization of the investigation procedure. In this report, we introduce the detailed procedures for the representative test method, the constant pressure injection test (CPIT), which is used to determine the key hydrogeological parameters of the subsurface fractured rock aquifer, namely hydraulic conductivity and storativity. This report further refines the standard test method suggested by the KSRM in 2022 and includes practical field application case conducted in volcanic rock aquifers where this investigation procedure has been applied.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제9권2호
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• pp.165-173
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• 1998

Objectives：This study was conducted to compare the cognitive characteristics and visual-motor coordination ability of children with Asperger’s disorder and with those of children with PDD NOS. Methods：27 children(13 in AS group and 14 in PDD NOS group) were individually assessed using the K-WISC and BGT, and the results of those tests were analyzed. Results：The mean FSIQ of the AS group was significantly higher than that of the PDD NOS group. There was also a large discrepancy between VIQ and PIQ in the PDD NOS, while there was not significant discrepancy in the AS. The AS was distinguished from PDD NOS group by significantly higher scores in Vocabulary and Comprehension subscales and lower score in Block design. Also, when compared with the PDD NOS, the AS showed more difficulties in visual-motor coordination. Conclusion：The AS showed relatively good verbal and learning ability, while the PDD NOS relatively superior ability in visuospatial function and visual-motor coordination. The findings indicated that the K-WISC and BGT might be useful assessment tool to differentiate the AS from PDD NOS.

• Journal of Gastric Cancer
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• 제22권2호
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• pp.120-134
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• 2022

Purpose: This study aimed to identify prognostic factors for patients with distant lymph node-involved gastric cancer (GC) using a machine learning algorithm, a method that offers considerable advantages and new prospects for high-dimensional biomedical data exploration. Materials and Methods: This study employed 79 features of clinical pathology, laboratory tests, and therapeutic details from 289 GC patients whose distant lymphadenopathy was presented as the first episode of recurrence or metastasis. Outcomes were measured as any-cause death events and survival months after distant lymph node metastasis. A prediction model was built based on possible outcome predictors using a random survival forest algorithm and confirmed by 5×5 nested cross-validation. The effects of single variables were interpreted using partial dependence plots. A contour plot was used to visually represent survival prediction based on 2 predictive features. Results: The median survival time of patients with GC with distant nodal metastasis was 9.2 months. The optimal model incorporated the prealbumin level and the prothrombin time (PT), and yielded a prediction error of 0.353. The inclusion of other variables resulted in poorer model performance. Patients with higher serum prealbumin levels or shorter PTs had a significantly better prognosis. The predicted one-year survival rate was stratified and illustrated as a contour plot based on the combined effect the prealbumin level and the PT. Conclusions: Machine learning is useful for identifying the important determinants of cancer survival using high-dimensional datasets. The prealbumin level and the PT on distant lymph node metastasis are the 2 most crucial factors in predicting the subsequent survival time of advanced GC.