• Journal of Preventive Medicine and Public Health
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• v.56 no.2
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• pp.111-127
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• 2023

Objectives: Pre-pregnancy diet has an important role in preparing for healthy generation. However, evidence on this issue has been scarce. A scoping review synthesising current evidence will support the demand to map 'what has been researched' on pre-pregnancy diet and maternal and child health. Methods: Systematic search was performed using PICOS (Population, Intervention, Comparison, Outcomes, and Study design) framework in electronic databases. Articles were screened for eligibility, summarized, and the quality was assessed using the National Institute of Health assessment tool. The review structure complies with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guide. Results: Forty-two articles were included after full-text screening. Twenty-five studies were in high-income countries (HICs), six in each upper-middle income, five in lower-middle income countries (LMICs), and one in low-income countries (LIC). Based on the regions: North America (n=16), Europe (n=5), South America (n=4), Australia (n=4), Asia (n=5), Middle East (n=2), and sub-Saharan Africa (n=1). The two-most observed diet-related exposures were dietary pattern (n=17) and dietary quality (n=12). The most assessed outcome was gestational diabetes mellitus (n=28) and fetal and newborn anthropometry (n=7). The average quality score±standard deviation was 70±18%. Conclusions: Research related to pre-pregnancy diet is still concentrated in HICs. The context of diet may vary; therefore, future research is encouraged in LMICs and LICs context, and Mediterranean, South-East Asia, Pacific, and African regions. Some maternal and child nutrition-related morbidity, such as anemia and micronutrient deficiencies, have not been discussed. Research on these aspects will benefit to fill in the gaps related to pre-pregnancy diet and maternal and child health.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4329-4337
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• 2022

Jet impinging device is designed for decay heat removal on horizontal fuel rods in a low temperature heating reactor. An experimental system with a fuel rod simulator is established and experiments are performed to evaluate water film covering capacity, within 0.0287-0.0444 kg/ms mass flow rate, 0-164.1 kW/m² heating flux and 13.8-91.4℃ feeding water temperature. An effective method to obtain the film coverage rate by infrared equipment is proposed. Water film flowing patterns are recoded and the film coverage rates at different circumference angles are measured. It is found the film coverage rate decreases with heating flux during single-phase convection, while increases after onset of nucleate boiling. Besides, film coverage rate is found affected by Marangoni effect and film accelerating effect, and surface wetting is significantly facilitated by bubble behavior. Based on the observed phenomenon and physical mechanism, dry-out depth and initial dry-out rate are proposed to evaluate film covering potential on a heating surface. A model to predict film coverage rate is proposed based on the data. The findings would have reliable guide and important implications for further evaluation and design of decay heat removal system of new reactors, and could be helpful for passive containment cooling research.

• Journal of the Korean Geotechnical Society
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• v.22 no.4
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• pp.61-71
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• 2006

A numerical procedure is presented fur evaluating seismic liquefaction on sloping ground sites. The procedure uses a fully coupled dynamic effective stress analysis with a plastic constitutive model called UBCSAND. The model was first calibrated against laboratory element behavior. This involved cyclic simple shear tests performed on loose sand with and without initial static shear stress. The numerical procedure is then verified by predicting a centrifuge test with a slope performed on loose Fraser River sand. The predicted excess pore pressures, accelerations and displacements are compared with the measurements. The results are shown to be in good agreement. The shear stress reversal patterns depend on static and cyclic shear stress levels and are shown to play a key role in evaluating liquefaction response in sloping ground sites. The sand near the slope has low effective confining stress and dilates more. When no stress reversals occur, the sand behaves in a stiffer manner that curtails the accumulated downslope displacements. The numerical procedure using UBCSAND can serve as a guide for design of new soil structures or retrofit of existing ones.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.38.4-39
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• 2021

The Local Volume Mapper (LVM), for the Sloan Digital Sky Survey V, consists of four 16 cm telescopes with three fiber spectrographs in the Las Campanas Observatory in Chile. With the fixed telescopes on optical tables, the Alt-Alt mounted siderostats point and guide targets during spectrograph exposures. We are developing the integrated LVM instrument control software. Considering international travel restrictions caused by the COVID-19 pandemic in 2021, we decided to make a simplified version of siderostat to test the LVM telescope control system in Korea. The prototype siderostat consists of two aluminum flat mirrors, optomechanical housing structures made by aluminum profiles, and the Planewave L-350 mount. We designed the optical mirrors and the optomechanical structure of the siderostat. From structural analysis at various pointing cases, we estimated the tilt misalignments of mirrors within 4 arcsec, which would affect the telescope pointing errors.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.3
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• pp.227-233
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• 2023

In this paper, to substitute the existing TWTA(Travailing Wave Tube Amplifier) component in small radar system, we developed the Ku band SSPA(Solid-State Power Amplifier) based on the fabrication of power MMIC (Monolithic Microwave Integrated Circuit) chips. For the development of the 500 W SSPA, the 40 W-grade power MMIC was designed by ADS(Advanced Design System) at Keysight company with UMS GH015 library, and was processed by UMS foundry service. And 70 W main power modules were achieved the 2-way T-junction combiner method by using the 40 W-grade power MMICs. Finally, the 500 W SSPA was fabricated by the wave guide type power divider between the drive power amplifier and power modules, and power combiner with same type between power modules and output port. The electrical properties of this SSPA had 504 W output power, -58.11 dBc spurious, 1.74 °/us phase variation, and -143 dBm/Hz noise level.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.213-221
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• 2023

The demand for Liquefied Natural Gas (LNG) carriers and LNG-fueled ships has significantly increased in recent years due to the sulfur-oxide emission regulations by the International Maritime Organization (IMO). The main goal of this paper is to introduce the process for the Engineering Critical Assessment (ECA) of IMO independent type-B cargo tanks made from 9% nickel alloy. A methodology proposed by the British Standard was used to conduct ECA for any structure with initial flaws. Based on this standard, a Matlab code was developed to perform ECA. Coarse mesh Finite Element Analysis (FEA) was performed on an independent type-B LNG cargo tank with a capacity of 15,000 m³. The location with the highest development of maximum principal stress was identified at the bottom of the cargo tank. Fine mesh FEA was performed to obtain the stress range required for ECA. The dynamic cargo tank loads used for FEA were determined using some ship rules presented by Det Norske Veritas. As a result of performing a 20-year long-term crack propagation analysis with a semi-elliptical surface crack, the fracture-to-yield ratio exceeded the Fracture Assessment Line (FAL) and some structural reinforcement was necessary. Performing a 15-day short-term crack propagation analysis, the fracture-to-yield ratio remained within the FAL, and no significant LNG leaks were expected. This paper is believed to provide a guide for performing ECA of LNG cargo tanks in the future by providing the basic theory and application sample necessary to perform ECA.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.320-322
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• 2021

As the world's elderly population increases, the proportion of visually impaired is also increasing, and there are still many restrictions on the use of outside activities, such as safety problems and lack of guidance information. To solve this problem, research on smart devices such as smart glasses with optical character recognition (OCR) function is being actively conducted. In this paper, we propose a system that recognizes obstacles ahead and informs information by voice, and also guides the way to the destination. Using the deep learning object recognition model Yolo, it let them to recognize the risk factors as obstacles such as stairs and Larva cones. and it also deliver the information with a voice. so you can expect that the visually impaired can do a lot of different activity even more now that system takes the visually impaired to the destination by using the directions API, voice recognition, TTS library.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.253-258
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• 2023

In comics, panels serve a variety of dramatic purposes, including controlling the flow of the story through the size, placement, and order of panels; directing the eye to where characters or specific actions take place; expressing the passage or sequence of time; and using backgrounds, lighting, and color to emphasize emotion and convey mood. When applied to VR animation, these comic panels can give users a more immersive experience of the cartoon world in the VR space. In the VR animation "Mescaformhill: Missing Five," produced in 2022, the comic panels directing is very important to guide the viewer's attention, and in the VR space, the camera angle can be freely changed to realize various visual effects, and the physical interaction brings the comic panels directing to life. This can open up new ways of storytelling in VR animation and contribute to its successful expansion into new mediums.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.343-352
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• 2020

Modular integrated construction (MiC) is an innovative construction method where components of a building are manufactured in an offsite factory, trucked to the job site in sections, set in place with cranes, and assembled together to form a whole building. Where circumstances merit, favorable conditions exist and implemented effectively; MiC improves project performance. However, several key factors need to converge during implementation to realize the full benefits of MiC. Thus, a thorough understanding of the factors which are critical to the success of MiC projects is imperative. Drawing on a systematic review of 47 empirical studies, this research identified 25 key success factors (KSFs) for MiC projects. Of these, the five topmost cited KSFs for MiC projects include effective working collaboration and communication among project participants; standardization, optimization, automation and benchmarking of best practices; effective supply chain management; early design freeze and completion; and efficient procurement method and contracting. The study further proposed a conceptual model of the KSFs, highlighting the interdependences of people, processes, and technology-related KSFs for the effective accomplishment of MiC projects. The set of KSFs is practically relevant as they constitute a checklist of items for management to address and deal with during the planning and execution of MiC projects. They also provide a useful basis for future empirical studies tailored towards measuring the performance and success of MiC projects. MiC project participants and stakeholders will find this research useful in reducing failure risks and achieving more desired performance outcomes. One potential impact of the study is that it may inform, guide, and improve the successful implementation of MiC projects in the construction industry. However, the rigor of the analysis and relative importance ranking of the KSFs were limited due to the absence of data.

• Journal of Digestive Cancer Research
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• v.4 no.1
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• pp.1-9
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• 2016

The abundance of multi-drug resistance ATPase binding cassette and deranged self-renewal pathways shown in cancer stem cells (CSCs) played a crucial role in tumorigenesis, tumor resistance, tumor recurrence, and tumor metastasis. Therefore, elucidation of CSCs biology can improve diagnosis, enable targeted treatment, and guide the follow up of GI cancer patients. In order to achieve chemoquiescence, seizing cancer through complete ablation of CSCs, CSCs are rational targets for the design of interventions that will enhance responsiveness to traditional therapeutic strategies and contribute in the prevention of local recurrence as well as metastasis. However, current cancer treatment strategies fail to either detect or differentiate the CSCs from their non-tumorigenic progenies mostly due to the absence of specific biomarkers and potent agents to kill CSCs. Recent advances in knowledge of CSCs enable to produce several candidates to ablate CSCs in gastrointestinal (GI) cancers, especially cancers originated from inflammation-driven mutagenesis such as Barrett's esophagus (BE), Helicobacter pylori-associated gastric cancer, and colitis-associated cancer (CAC). Our research teams elucidated through revisiting old drugs that proton pump inhibitor (PPI) and potassium competitive acid blocker (p-CAB) beyond authentic acid suppression, chloroquine for autophage inhibition, sonic hedgehog (SHH) inhibitors, and Wnt/β-catenin/NOTCH inhibitor can ablate CSCs specifically and efficiently. Furthermore, nanoformulations of these molecules could provide an additional advantage for more selective targeting of the pathways existing in CSCs just like current molecular targeted therapeutics and sustained action, while normal stem cells intact. In this review article, the novel approach specifically to ablate CSCs existing in GI cancers will be introduced with the introduction of explored mode of action.