The Use of Interactive Toys in Children’s Pretend Play: An Experience Prototyping Approach

홍지우,이우훈 한국디자인학회 2019 디자인학연구 Vol.32 No.3

Background: Interactive technology can greatly enhance several behavioral and cognitive aspects of children’s play. However, little is known about the manner in which children accept and use technology in toy-based play. Therefore, in this study, we adopted the experience prototyping approach to examine how children and parents utilize digitally enhanced toys, especially in pretend play that entails symbolic and social behaviors. Methods: We used several types of experience prototypes that could augment traditional non-digital toys in an interactive manner. A user study was conducted using a sample of eight parent-child dyads. Their play behaviors using the provided experience prototypes were observed. Additionally, a post-play semi-structured interview was conducted to further explore the thoughts and intentions that underlay play behaviors. Results: The results revealed that children used the predetermined and open-ended symbolic stimuli of the experience prototypes to create symbolic pretenses. Digitally enhanced toys helped children exhibit imitative actions and constructive behaviors. We also identified the opportunities and challenges that children encounter when interactive systems are used in social pretend play. With respect to input methods, participants preferred the system with a simple way of manipulation. Conclusions: Overall, children and parents expressed their needs, preferences, expectations, and frustrations regarding the use of interactive technology in symbolic and social pretend play. The findings and implications of this study can be informative to toy designers and researchers who are interested in developing interactive tools or systems for children.

와류 발생기의 공동 유동 특성에 관한 연구

홍지우,김영진,안병권 한국가시화정보학회 2023 한국가시화정보학회지 Vol.21 No.3

In this study, we present experimental results of cavitating flow around a vortex generator which is used to improve the flow in the wake of ships and enhance propulsion efficiency. We conducted experiments at the CNU cavitation tunnel on a total of six vortex generators, two different aspect ratios and three taper ratios. We recorded cavity patterns using a high-speed camera and quantitatively evaluated cavity fraction using OpenCV. The most important finding of this study is that the vortex cavity generated at a root leading edge of the vortex generator develops at a specific angle.

Fabrication of Solvent-free CsPbBr3Films Using Aerosol Deposition for White LED-Chip Scale Packaging

홍지우,김성훈 한국공업화학회 2024 한국공업화학회 연구논문 초록집 Vol.2024 No.0

秘方奪命散의 抗炎症效果 및 抗凝固作俑에 대한 硏究

田炳薰,禹元洪,洪知雨 대한동의병리학회 1998 동의생리병리학회지 Vol.12 No.2

丹溪心法에 最初로 收錄되어 一切癰疽 無名惡瘡을 治療하는데 使用되는 秘方奪命散이 염증 및 血栓의 치료에도 유효한 처방으로 생각되어 본 실험을 계획하였으며, 비방탈명산의 抗炎症 作用, 抗血栓作用, 鎭痛效果를 觀察한 結果, 有意性이 認定되었다. 秘方奪命散의 抗炎症 效果를 알아보기 위하여 carragenin을 利用한 局所的浮腫 實驗과 炎症反應時 나타나는 血管透過性亢進으로 因한 蛋白質渗出의 抑制를 觀察하기 위하여 CMC-pouch를 利用하여 蛋白質 渗出을 測定하였다. 醋酸法과 熱板法으로 鎭痛效果를 관찰하였다. 抗血栓效果를 究明하기 위하여 肺性血栓性塞栓症에서의 死亡率, 血小板 凝集度, 血漿凝固活性, 관찰했던 바, 다음과 같은 結果를 얻었다. carragenin으로 誘發한 後肢足蹠의 浮腫은 檢液投與 2,3時間 後에 BTS Ⅱ,Ⅲ群에서 有意性있는 抑制效果과 있었고, CMC-pouch에 의한 蛋白質 渗出은 BTS Ⅱ,Ⅲ群에서 有意性 있는 減少를 보였으나 aspirin藥物 對照群보다는 微弱하였다. 醋酸法과 熱板法에 의해 writhing syndrome, paw licking time, escape time을 측정한 결과, 一定한 鎭痛效果를 確認할 수 있었다. 秘方奪命散의 抗血栓效果는 serotonin과 collagen 混合液으로 誘發한 肺性血栓性 塞栓症에서의 死亡率 減少 血小板 凝集 抑制등의 효과를 보였으나, 혈장응고활성을 측정한 prothrombin time과 activated partial thromboplastin time은 연장되는 결과를 보이기는 하였으나 유의한 결과는 아니었다. This study was designed to elucidate the antiinflammatory, antithrombotic, and analgesic effect of Bibangtalmyungsan and antiflammatory effects was measured by the method of carrageenin induced edema, protein leakage test using CMC-pouch. Death rate, platelet aggregation, plasma coagulation activity, prothrombin time and activated partial thromboplastin time were observed for the measurement of the antithrombotic effect of Bibangtalmyungsan, and the analgesic effect was measured by the acetic acid method and hot plate method. The result was as follows : After 2 or 3 hours of Bibangtalmyungsan administration, carrageenin induced edema and CMC-pouch protein leakage was significantly decreased. The slight anagesic effect of Bibangtalmyungsan extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. The antithrombotic effect of Bibangtalmyungsan was observed by the decrease of death rate, the inhibition of platelet aggregation, and the increase of antithrombin activity. It increased the prothrombin time and activated partial thromboplastin time.

Effect of Myconastes homosperai Ultrasound Extract on Anti-oxidant and Cell Viability in RAW264.7.

홍지우,김진우,김준희,이은재,박하영,강민호 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.-

Effect of Myconastes homosperai Ultrasound Extract on Anti-oxidant and Cell Viability in RAW264.7.

홍지우,김진우,김준희,이은재,박하영,강민호 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.-

괭생이모자반 추출물의 리파아제 저해 활성 및 3T3-L1 지방전구세포 분화억제 효과

홍지우,박하영,박재현,김소희,김한아,김진우 한국해양과학기술원 2022 Ocean and Polar Research Vol.44 No.1

In this study, in order to evaluate the anti-obesity effect of sargassum horneri extract, the effects of the extract on lipase activity and preadipocyte differentiation in 3T3-L1 cells were investigated. S. horneri extract between 0.0 and 1.0 mg/mL showed no cytotoxicity and inhibited lipase activity by 68.1%. When S. horneri extract was utilized at levels of 0.25, 0.5, and 1.0 mg/mL in 3T3-L1 cells, preadipocytes differentiation decreased by 11.4, 19.7, and 25.6%, respectively, showing anti-obesity effects. In addition, after treatment with 1.0 mg/mL S. horneri extract, the mRNA expression levels of sterol regulatory element binding proteins-1c (SREBP-1c), peroxisome proliferator activated receptor-γ (PPAR-γ), CCAAT enhancer binding protein-α (CEBP-α), fatty acid synthase (FAS), and stearoyl-CoA desaturase1 (SCD1) in 3T3-L1 cells were significantly decreased (p < 0.05) by 65.2, 54.9, 50.0, 33.8, and 33.8% respectively. These results showed that S. horneri extract suppresses lipase activity and prophylactic preadipocyte differentiation in 3T3-L1, and thus can be used as an anti-obesity agent in functional foods and medicines.

전기습윤 시 액적의 스위칭 시간

홍지우(Jiwoo Hong),강관형(Kwan Hyoung Kang) 한국가시화정보학회 2009 한국가시화정보학회 학술발표대회 논문집 Vol.2009 No.11

It is very important to predict the time response of electrowetting-based devices, such as liquid lenses, reflective displays, and optical switches. We investigated the time response of electrowetting, based on an analytical method to find out characteristic scales and a scaling law for the switching time. For this, spreading process of a sessile droplet was analyzed based on the domain perturbation method. First, we considered the case of weakly viscous fluids. The analytical result for the spreading process was compared with experimental results, which showed very good agreement in overall time response. We derived characteristic scales combining the droplet volume, density, and surface tension. A scaling law was derived from the analytical solution and was verified experimentally.

콩나물부산물로부터 열수추출을 이용한 폴리페놀과 플라보노이드 생산

홍지우 ( Ji Woo Hong ),감다혜 ( Da Hye Gam ),김화영 ( Hwa Young Kim ),김진우 ( Jin Woo Kim ) 조선대학교 공학기술연구원 2020 공학기술논문지 Vol.13 No.4

Spent bean sprouts (SBS) are produced during the cultivation, cleaning, and packaging processes for bean sprouts. They account for 50% of total bean sprout production and cause environmental problems and waste disposal costs. This study was conducted to produce bioactive materials including phenolic compounds and flavonoids from SBS in order to produce value-added materials and reduce waste disposal costs. The optimization of extraction conditions was investigated for selection of solvents and evaluation of the effects of main variables, including solvent concentration, extraction temperature, and extraction time. Among these three variables, ethanol concentration showed the greatest effects on the production of total phenolic compound (TPC) and total flavonoid content (TFC). The optimal extraction condition was found to be 57.2˚C, 78.7 min, and 39.0% ethanol (v/v), which resulted in 28.0 mg GAE/g DM for TPC and 1.52 mg QE/g DM for TFC. The production of high concentrations of phenol compounds and flavonoids from SBS by hot-water extraction proves that SBS can be used in the production of functional food and cosmetics materials.

PIV와 LDV를 이용한 냉각수 토출구 주위의 와류 가시화 연구

홍지우(Ji-Woo Hong),신수용(Su-Yong Shin),안병권(Byoung-Kwon Ahn) 한국가시화정보학회 2021 한국가시화정보학회지 Vol.19 No.3

Submerged and semi-submerged vehicles expel cooling water through an outlet. In this process, induced noise and vibration by the flow around the outlet have been reported, and it may cause problems directly related to survivability of the navy vessels. The coolant outlet has a net-type structure and circular columns are mostly used. In this study, flow measurements using PIV and LDV were performed for different type outlets; conventional (flat plate with round bar) and improved (flat and flat plate) configurations. Experiments were conducted at a cavitation tunnel where pressure and steady flow rate conditions are ensured for sufficient time to measure the flow. The average velocity field of the outlets were measured and compared through LDV measurements, and instantaneous vorticities were evaluated through PIV measurements. The results show that the improved type of the outlet is advantageous in terms of flow stability compared to the conventional type of the outlet.