• Journal of the Semiconductor & Display Technology
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• v.22 no.1
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• pp.28-32
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• 2023

Recently, the use of stable lithium nanostructures as substrates and electrodes for secondary batteries can be a fundamental alternative to the development of next-generation system semiconductor devices. However, lithium structures pose safety concerns by severely limiting battery life due to the growth of Li dendrites during rapid charge/discharge cycles. Also, enabling long cyclability of high-voltage oxide cathodes is a persistent challenge for all-solid-state batteries, largely because of their poor interfacial stabilities against oxide solid electrolytes. For the development of next-generation system semiconductor devices, solid electrolyte nanostructures, which are used in high-density micro-energy storage devices and avoid the instability of liquid electrolytes, can be promising alternatives for next-generation batteries. Nevertheless, poor lithium ion conductivity and structural defects at room temperature have been pointed out as limitations. In this study, a low-dimensional Graphene Oxide (GO) structure was applied to demonstrate stable operation characteristics based on Li+ ion conductivity and excellent electrochemical performance. The low-dimensional structure of GO-based solid electrolytes can provide an important strategy for stable scalable solid-state power system semiconductor applications at room temperature. The device using uncoated bare NCA delivers a low capacity of 89 mA h g-1, while the cell using GO-coated NCA delivers a high capacity of 158 mA h g−1 and a low polarization. A full Li GO-based device was fabricated to demonstrate the practicality of the modified Li structure using the Li-GO heterointerface. This study promises that the lowdimensional structure of Li-GO can be an effective approach for the stabilization of solid-state power system semiconductor architectures.

• Steel and Composite Structures
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• v.48 no.1
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• pp.19-25
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• 2023

Due to high application of concrete structures in construction industry, however, the quality improvement is essential. One of the new ways for this purpose is adding the nanoparticles to the concrete. In this work, vibration analysis of concrete beams reinforced by graphene oxide (GO) nanoparticles based on mathematical model has been investigated. For the accuracy of the presented model, the experimental study is done for comparing the compressive strength. Since the nanoparticles can not be solved in water without any specific process, at the first, GO nanoparticles should be dispersed in water by using shaker, magnetic striker, ultrasonic devices and finally mechanical mixer. For modelling of the strucuture, sinusoidal shear deformation beam theory (SSDBT) is utilized. Mori-Tanak model model is utilized for obtaining the effective properties of the beam including agglomeration influences. Utilizing the energy method and Hamilton's principal, the motion equations are calculated. The frequency of the concrete beam is obtanied by analytical method. Three samples with 0.02% GO nanoparticles are built and its compressive strength is compared which shows a good accuracy with maximum 1.29% difference with mathematical model and other papers. The aim of this work from the theoretical study is investigating the effects of nanoparticles volume percentage and agglomeration, length and thickness of the beam on the frequency of the structure. The results show that the with enhancing the GO nanoparticles, the frequency is increased. For example, with enhancing the volume percent of GO nanoparticles from zero to 0.08%, the compressive strength is increased 48.91%. and 46.83%, respectively for two cases of with and without agglomeration.

• BMB Reports
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• v.57 no.5
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• pp.232-237
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• 2024

This study investigated how adipose tissue-derived mesenchymal stem cells (AT-MSCs) respond to chondrogenic induction using droplet-based single-cell RNA sequencing (scRNA-seq). We analyzed 37,219 high-quality transcripts from control cells and cells induced for 1 week (1W) and 2 weeks (2W). Four distinct cell clusters (0-3), undetectable by bulk analysis, exhibited varying proportions. Cluster 1 dominated in control and 1W cells, whereas clusters (3, 2, and 0) exclusively dominated in control, 1W, and 2W cells, respectively. Furthermore, heterogeneous chondrogenic markers expression within clusters emerged. Gene ontology (GO) enrichment analysis of differentially expressed genes unveiled cluster-specific variations in key biological processes (BP): (1) Cluster 1 exhibited up-regulation of GO-BP terms related to ribosome biogenesis and translational control, crucial for maintaining stem cell properties and homeostasis; (2) Additionally, cluster 1 showed up-regulation of GO-BP terms associated with mitochondrial oxidative metabolism; (3) Cluster 3 displayed up-regulation of GO-BP terms related to cell proliferation; (4) Clusters 0 and 2 demonstrated similar up-regulation of GO-BP terms linked to collagen fibril organization and supramolecular fiber organization. However, only cluster 0 showed a significant decrease in GO-BP terms related to ribosome production, implying a potential correlation between ribosome regulation and the differentiation stages of AT-MSCs. Overall, our findings highlight heterogeneous cell clusters with varying balances between proliferation and differentiation before, and after, chondrogenic stimulation. This provides enhanced insights into the single-cell dynamics of AT-MSCs during chondrogenic differentiation.

• Journal of Korea Port Economic Association
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• v.24 no.4
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• pp.257-281
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• 2008

This study aims to draw meaningful points from the Chang Po Go period in which Chang Po Go, who established an integrated logistics system while operating on the seas of three nations including Japan, China, and Shilla by taking Chunghaejin, Shilla, as a base of operations in the 9th century, and to discover the need for the construction of the logistics system in northeast Asia. Also, the study intends to propose strategies for contemporary application of the logistics system used during the Chang Po Go period, based on the modern logistics concept. As a result of specifically reviewing the lesson from the Chang Po Go period, which created a paradigm for a new cooperation in logistics, the leadership of the CEO, who is prepared with the long-term vision of Chang Po Go, the implementation of an integrated system for logistics activity, and the political support of the government for private companies, will initiate a bright outlook for the construction of the logistics system in northeast Asia, amid the growing need for cooperation in logistics among the three northeast Asian countries. In this era in which northeast Asia is emerging as the center of the world economy, the cooperative model in the logistics field, which transcended the border of Chang Po Go, who built a maritime logistics network in the 9th century, will help implement a cooperative logistics system in the northeast Asian region.

• Korean Journal of Health Education and Promotion
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• v.24 no.5
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• pp.103-118
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• 2007

Housewives' perception on obesity related variables to their family members according to the composition of children in the family was explored. Ninety housewives responded to a questionnaire consisted of sociodemographic informations, body weight perception, eating behaviors perception, and physical activity level for herself as well as her family. They were categorized into three groups based on child composition of the family; boys only (BO), girls only (GO), and boys and girls (BG) families. Boys in BO showed higher value of height, weight, and WHR than girls in GO (p <.05), while no differences were noticed in BMI and the waist girth between the groups. Mothers of BO perceived boys were active while mother of GO did girls were inactive (p <.05). Girls in GO ate meals less regularly than boys in BO and girls in BG. In general, housewives' perception on body weight of family members was relied on BMI and waist girth. As mother's BMI increased, the boy's BMI in BO was also elevated (p <.05), but not in others. Mothers' perception on caloric intake and activity encouragement were not accounted for morphological characteristics. Results suggest that housewives perceived obesity related variables differently based on the composition of children of the family.

• Membrane Journal
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• v.24 no.2
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• pp.151-157
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• 2014

In this study, the nanofiber composite membrane was prepared by electrospinning method with poly (ancrylonitrile) (PAN) and a dispersed solution of graphene oxide (GO) and $Fe_3O_4$ functionalized graphene oxide (M-GO) in dimethyl formamide (DMF). The pore-diameter of prepared membranes was controlled by change of those layers. It was confirmed with SEM that the nanofiber composite membranes having fiber size of 500 nm were prepared. It was found with Raman spectroscopy and EDS that GO and M-GO were well dispersed on those membranes. Final nanofiber composite membrane showed the similar pore properties ($0.21{\sim}0.24{\mu}m$/pore-size, 40% porosity) with the commercial membrane ($0.27{\mu}m$/pore-size, 55% porosity) and their water-flux results also showed the 200% higher flux than its PAN membrane. From these results, it was expected that the nanofiber composite membrane prepared by electrospinning method could be utilized as a water-treatment membrane.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.705-713
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• 2017

A novel material, $Bi_2WO_6-GO-TiO_2$ composite, was successfully synthesized using a facile hydrothermal method. During the hydrothermal reaction, the loading of $Bi_2WO_6$ and $TiO_2$ nanoparticles onto graphene sheets was achieved. The obtained $Bi_2WO_{6-GO-TiO2}$ composite photo-catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (UV-vis-DRS), and X-ray photoelectron spectroscopy (XPS). The $Bi_2WO_6$ nanoparticle showed an irregular dark-square block nanoplate shape, while $TiO_2$ nanoparticles covered the surface of the graphene sheets with a quantum dot size. The degradation of rhodamine B (RhB), methylene blue trihydrate (MB), and reactive black B (RBB) dyes in an aqueous solution with different initial amount of catalysts was observed by UV spectrophotometry after measuring the decrease in the concentration. As a result, the $Bi_2WO_6-GO-TiO_2$ composite showed good decolorization activity with MB solution under visible light. The $Bi_2WO_6-GO-TiO_2$ composite is expected to become a new potential material for decolorization activity. Photocatalytic reactions with different photocatalysts were explained by the Langmuir-Hinshelwood model and a band theory.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.9
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• pp.979-986
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• 2010

This paper presents an algorithm for retrieving precise radar cross sections(RCS) of various trihedral corner reflectors (TCR) which are external calibrators of synthetic aperture radar(SAR) systems. The theoretical RCSs of the TCRs are computed based on the physical optics(PO), geometrical optics(GO), and physical theory of diffraction(PTD) techniques; that is, the RCS computation includes the single reflections(PO), double reflections(GO-PO), triple reflections(GO-GO-PO), and edge diffractions(PTD) from the TCR. At first, we acquire an SAR image of the area that five TCRs installed in, and then extract the RCS of the TCRs. The RCSs of the TCRs are extracted accurately from the SAR image by adding up the power spill, which is generated due to the radar IRF(Impulse Response Function), using a square window. We compare the extracted RCSs with the theoretical RCSs and analyze the difference between the theoretical and experimental RCSs of the TCR for various window sizes and various backscattering coefficient levels of the adjacent area. Finally, we propose the minimum size of the integration area and the maximum level of the backscattering coefficients for the adjacent area.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.24 no.2
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• pp.291-304
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• 1994

The purpose of this study was to analyze the facial asymmetry of the patients with the craniomandibular disorder. In this study, 50 patients, who have joint clicking and pain, mouth opening limitation, and 40 dental students, Chosun University, who did not posses any restoration and orthodontic treatment, joint clicking and pain, mouth opening limitation, were selected as the control group. Both the control group and the patient group were takened skull P-A, submento-vertex radiogram by standized methods. After that, the deviation and facial asymmetry were measured and analyzed. The results of the this study were as follows: 1. In the Skull P-A radiogram, the width difference of control group and patient group measured that the △ Cg-Go-Cl: control group were 3.35㎜, patient group were 4.51㎜ (P<0.05), the △Cg-Zy-Go: control group were 1.83㎜, patient group were 3.27㎜(P<0.001). 2. In the Skull P-A radiogram, the height difference of control group and patient group measured that the △ Cg-Go-Cl: control group were 131.85㎜, patient group were 188.45㎜(P<0.05), the △Cg-Zy-Go: control group were 1.58㎜, patient group were 2.68㎜(P<0.00l). 3. In the Skull P-A radiogram, the area difference of control group and patient group measured that the △ Cg-Go-Cl: control group were 120.76㎟, patient group were 185.49㎟(P<0.05), the △Cg-Zy-Go: control group were 2.29㎟, patient group were 3.37㎟(p<0.05). 4. In the submento-vertex radiogram, the width difference of control group and patient group measured that the △Mr-Cl-Ia: control group were 1.50㎜, patient group were 2.35㎜(P<0.05), the △Mr-Cm-Ia: control group were 1.75㎜, patient group were 3.17㎜(P<0.05), the △Mr-Go-Ia: control group were 1.96㎜, patient group were 3.24㎜(P<0.001), the △Mr-Cp-Co: control group were 1.74㎜, patient group were 2.73㎜(P<0.05). 5. In the submento-vertex radiogram, the height difference of control group and patient group measured that the △Mr-Cp-Ia: control group were 1.68㎜, patient group were 2.46㎜P<0.05), the △Mr-CI-Ia: control group were 2.38㎜, patient group were 3.74㎜(P<0.05), the △Mr-Co-Ia: control group were 1.63㎜, patient group were 2.80㎜(P<0.05), the △Mr-Cm-Ia: control group were 1.45㎜, patient group were 3.12㎜(P<0.001). 6. In the submento-vertex radiogram, the area difference of control group and patient group measured that the △ Mr-Cp-Ia: control group were 73.17㎟, patient group were 110.16㎟(P<0.05), the △Mr-Cl-Ia: control group were 105.09㎟, patient group were 180.87㎟(P<0.001), the △Mr-Co-Ia: control group were 103.31㎟, patient group were 148.48㎟(P<0.05), the △Mr-Cm-Ia: control group were 97.01㎟, patient group were 167.83㎟(P<0.05), the △Mr-Go-Ia: control group were 104.24㎟, patient group were 205.90㎟(P<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.761-766
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• 2008

The effects of various enzymes and emulsifiers on the loaf volume and crumb hardness of rice breads were studied. Four different enzymes [fungal ${\alpha}$-amylase (AMYL), maltogenic bacterial ${\alpha}$-amylase (NMYL), glucose oxidases (GO), and xylanase+hemicellulases (PTP)] and four emulsifiers [sorbitan monostearate (SMS), glycerol monostearate (GMS), sodium stearoyl lactylate (SSL), and glycerol ester+propylene glycol ester+sucrose ester+sorbitan ester (SP)] were supplemented to rice dough. The addition of AMYL, GO, and GO+AMYL increased loaf volume of rice breads. The highest loaf volume was observed in rice bread supplemented with AMYL. Rice breads supplemented with enzymes firmed at lower rates during storage, and AMYL, NMYL, and GO considerably decreased crumb hardness of rice breads, exhibiting a significant antistaling effect. The addition of emulsifiers produced rice breads with better specific loaf volume and crumb texture, and continuously retarded crumb hardness of rice breads during storage. Especially, rice bread supplemented with SSL demonstrated the highest loaf volume and the lowest crumb hardness during storage.