• Journal of Positioning, Navigation, and Timing
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• 제3권3호
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• pp.123-129
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• 2014

The real-time kinematic (RTK) is one of precise positioning methods using Global Positioning System (GPS) data. In the long baseline GPS RTK, the ionospheric and tropospheric delays are critical factors for the positioning accuracy. In this paper we present RTK algorithms for long baselines more than 100 km with estimating tropospheric delays. The state vector is estimated by the extended Kalman filter. We show the experimental results of GPS RTK for various baselines (162.10, 393.37, 582.29, and 1283.57 km) by using the Korea Astronomy and Space Science Institute GPS data and one International GNSS Service (IGS) reference station located in Japan. As a result, we present that long baseline GPS RTK can provide the accurate positioning for users less than few centimeters.

• Clinical and Experimental Pediatrics
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• 제61권12호
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• pp.375-380
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• 2018

With the increase in the prevalence of overweight and obesity worldwide, early adiposity rebound, which is known to have a strong association with obesity, has recently been a focus of research. Early adiposity rebound is conventionally known to have a close relationship with non-communicable diseases. However, novel insights into early adiposity rebound have implied an acceleration of growth and puberty, which is directly reflected in the trends in the timing of adiposity rebound, in the 21st century compared with in the past. Furthermore, the observation that lean mass changes rather than fat mass changes show a more similar pattern to body mass index trajectories is interesting. In this article, the later outcomes and risk factors of early adiposity rebound are briefly summarized, and the current trends in the timing of adiposity rebound and novel insights into its relationship with body composition are reviewed.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제26권1호
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• pp.1-14
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• 2023

Foreign body (FB) ingestion is a common health problem that affects children more than adults. According to gastroenterologists' guidelines, the management of FB ingestion differs slightly between adult and children. This review aimed to compile adult and children guidelines and establish an understandable association to reveal the requirements and timing of the endoscopic procedure, which is the most effective and least complicated technique for gastrointestinal FBs. Coins, pins, and chicken and fish bones have been the most commonly ingested FBs. However, with their increasing use in recent years, large batteries with lithiumion conversion, stronger magnets composed of rare earth metals, such as neodymium, and superabsorbent objects have become the most morbid and mortal, necessitating new management strategies. Although the approach to gastrointestinal FBs is controversial, with different treatment options available in different disciplines, many studies have demonstrated the efficacy and safety of endoscopic procedures. Many factors influence the timing of endoscopy, including the nature, size, and location of the ingested object and the patient's clinical condition.

• International journal of advanced smart convergence
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• 제8권1호
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• pp.87-97
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• 2019

Data mining technology is applied to various fields because it is a technique for analyzing vast amount of data and finding useful information. In this paper, we propose a big data analysis method that uses Apriori algorithm, which is a data mining technique, to find the related factors that have negative and positive influences on school adjustment. Among Korea Child and Youth Panel Survey(KCYPS), data related to adjustment to school life and data showing parental inclinations were extracted from the data of fourth grade elementary school students, first year middle school students, and high school freshman students, respectively and we have mapped the useful association rules among them. As a result, the factors affecting school adjustment were different according to the timing of the growth process, we were able to find interesting rules by looking for connections between rules. On the other hand, the factors that positively influenced school adjustment were not significantly different from each other, and overall, they were associated with positive variables.

• 상하수도학회지
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• 제16권6호
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• pp.686-699
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• 2002

The purpose of this study is to estimate deterioration factors and weighting factors in pipe network which each local self-governments takes rehabilitation and replacement work present time. Deterioration factors in pipe network are able to effected of specific province or location related with water supply. Most of water supply pipes are laid under the ground, it is hard to quantify deterioration degree of water system. Moreover, the timing and economic limitation and insufficient information on the spot survey gives a difficulty to look over how old water supply system is. Accordingly, this study collects and analyses five data as the laying environment, visual analysis, analysis of soil contents, analysis of pipe material, and questionary survey data in water pipe of A city. The deterioration factor estimates 14 factors with excavation and experimental analysis and 9 factors without excavation and experimental analysis. Also, the weighting factors are estimated by using the multiple linear regressions and the linear programming. The estimated deterioration factor and weighting results are compared the analysis result of visual, pipe material, and soil contents with the Probabilistic Neural Network Model. Consequently, the model results of estimated 9 factors in this study and 14 factors show the 1-2% difference. The result show that the proposed model could be used to decide the deterioration condition of pipe line with real excavation and experimental analysis.

• Journal of Gastric Cancer
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• 제11권1호
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• pp.46-54
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• 2011

Purpose: There are few studies that have focused on the predictors of recurrence after gastrectomy for gastric carcinoma. This study analyzed the patients who died of recurrent gastric carcinoma and we attempted to clarify the clinicopathologic factors that are associated with the timing of recurrence. Materials and Methods: From June 1992 to March 2009, 1,795 patients underwent curative gastric resection at the Department of Surgery, Hanyang University College of Medicine. Among them, 428 patients died and 311 of these patients who died of recurrent gastric carcinoma were enrolled in this study. The clinicopathologic findings were compared between the 72 patients who died within one year after curative gastrectomy (the early recurrence group) and the 92 patients who died 3 years after curative gastrectomy (the late recurrence group). Results: Compared with the late recurrence group, the early recurrence group showed an older age, a more advanced stage, a poorly differentiated type of cancer and a significantly higher tendency to have lymphatic invasion, vascular invasion and perineural invasion.Especially in the gastric cancer patients with a more advanced stage (stage III and IV), the early recurrence group was characterized by a significantly higher preoperative serum carcino embryonic antigen level, perineural invasion and a relatively small number of dissected lymph nodes. Conclusions: The clinicopathologic characteristics of recurrent gastric cancer are significantly different according to the stage of disease, and even in the same stage. For the early detection of recurrence after curative surgery, it is important to recognize the clinicopathological factors that foretell a high risk of recurrence. It is mandatory to make an individualized surveillance schedule according to the clinicopathologic factors.

• Journal of Korean Neurosurgical Society
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• 제59권5호
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• pp.498-504
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• 2016

Objective : Although subdural hematoma (SDH) is commonly treatable by burr hole surgery in the late subacute or chronic stage, there is no clear consensus regarding appropriate management and exact predictive factors for postoperative recurrence also remain unclear. The aim of this study was to evaluate risk factors associated with recurrence of SDH that requires burr hole surgery in the late subacute or chronic stage. We also identified the appropriate timing of surgery for reducing the recurrence. Methods : We retrospectively reviewed 274 patients with SDH in the late subacute or chronic stage treated with burr hole surgery in our hospital between January 2007 and December 2014. Excluding patients with acute intracranial complications or unknown time of trauma onset left 216 patients included in the study. Results : Of 216 patients with SDH in the late subacute or chronic stage, recurrence was observed in 36 patients (16.7%). The timing of the operation in patients with late subacute stage (15-28 days) resulted in a significant decrease in recurrence (RR, 0.33; 95% CI, 0.17-0.65; p=0.001) compared to chronic stage (>28 days). Otherwise, no significant risk factors were associated with recurrences including comorbidities and surgical details. Conclusion : The results indicated that time from trauma onset to burr hole surgery may be important for decreasing the risk of recurrence. Therefore, unless patients can be treated conservatively without surgery, prompt surgical management is recommended in patients diagnosed as having late subacute or chronic subdural hematoma treatable by burr hole surgery, even when neurological deficits are unclear.

• 한국지역사회생활과학회지
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• 제18권4호
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• pp.639-653
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• 2007

The purpose of this study was to investigate factors affecting the decisions regarding second births. Especially, analysis focused on the connections between desire for a second birth and the family factors such as family values and marital relations because they have been rarely known until now. Data was from 1,156 married women that had only one child and had been part of the national data collected by KIHASA in 2003. Major findings can be summarized as follows. First, it was found that value-related factors affect the likelihood of a second birth. The degree of parental responsibility is negatively related with the desire for a second birth. However, the perceived ideal number of children is positively related to it. Second, it was found that the quality of family relations influences the decision for the second birth. Particularly, marital satisfaction is likely to be the most important factor tending to mediate the effects of socio-demographic factors and value-related factors on the plan for a second birth. These results suggest that the effects of social norms on the number of children and timing of childbearing which exist in the family are becoming weaker. Nevertheless, the traditional value of children such as a preference for a son can still be found.

• Asia pacific journal of information systems
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• 제9권3호
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• pp.111-126
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• 1999

Current audit reports on IS development projects provide useful information to stakeholders but have such limitations as the lack of quantification of audit results and the insufficient recommendations on success factors. The purpose of this study is to solve these limitations, leading audit reports to become of future-oriented contents and form. This research was conducted through the logical inference from the review on the related literature, the analysis of audit reports from 1996 to 1998, and the collection of data from interviews and questionnaires with IS auditors. As a result of the study, eighteen success factors were identified for the development of IS projects, including the adequate composition of the system development team, the degree of project manager's cooperation with the client organization, and the timing of decision making.

• 한국조리학회지
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• 제11권2호
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• pp.14-31
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• 2005

The findings of the study would be valuable for the basis of marketing strategies to be implemented in the foodservice industry. As a result of the exploratory factor analysis, major consumer dissatisfaction factors identified in this study can be categorized based on the followings: food, service, and facilities. It appears that most preferred medium for unsatisfied consumers to file their employees how to cope with complaints on the Internet. In terms of psychological compensation, it appears that consumers need to be provided with a through explanation in addition to a heartfelt apology against a complaint. On the physical side of compensation solution for everybody. The ideal timing of compensation for complaints can vary but it would be appropriate to leave it up to consumers to choose when they want to be rewarded.