Effect of elevated temperatures on properties and color intensities of fly ash mortar

Her-Yung Wang 사단법인 한국계산역학회 2008 Computers and Concrete, An International Journal Vol.5 No.2

This research examines the engineering properties and color intensities of mortar containing different amounts of fly ash (0, 5, 10 and 20%) mixed at different water-to-binder ratios (w/b = 0.23, 0.47 and 0.59) and exposed at different temperatures (T = 25, 100, 200, 400, 600 and 800oC). Results show that there is greater mass loss on ignition with high w/b and higher temperatures. In addition, the color channel image analyzer (Windows software written in Delphi) is utilized to study the relationship between the curing temperature and intensity of three primary colors, red, green and blue (RGB), of the fly ash mortar specimens. The results show that the RGB intensities on the specimen surface increases from that at 25oC. The mortar specimen becomes white with increase in w/b but without the addition of fly ash. Moreover, for mortar specimens with greater content of fly ash, red on the specimen surface has the greatest increase in intensity at elevated temperature. Observation the variations in color on the specimen surface may help estimate the highest elevated temperatures that concrete structures can withstand.

Properties of recycled green building materials applied in lightweight aggregate concrete

Her-Yung Wang,Darn-Horng Hsiao,Shi-Yang Wang 사단법인 한국계산역학회 2012 Computers and Concrete, An International Journal Vol.10 No.2

This study uses recycled green building materials based on a Taiwan-made recycled mineral admixture (including fly ash, slag, glass sand and rubber powder) as replacements for fine aggregates in concrete and tests the properties of the resulting mixtures. Fine aggregate contents of 5% and 10% were replaced by waste LCD glass sand and waste tire rubber powder, respectively. According to ACI concretemixture design, the above materials were mixed into lightweight aggregate concrete at a constant water-tobinder ratio (W/B = 0.4). Hardening (mechanical), non-destructive and durability tests were then performed at curing ages of 7, 28, 56 and 91 days and the engineering properties were studied. The results of these experiments showed that, although they vary with the type of recycling green building material added, the slumps of these admixtures meet design requirements. Lightweight aggregate yields better hardened properties than normal-weight concrete, indicating that green building materials can be successfully applied in lightweight aggregate concrete, enabling an increase in the use of green building materials, the improved utilization of waste resources, and environmental protection. In addition to representing an important part of a “sustainable cycle of development”, green building materials represent a beneficial reutilization of waste resources.

Study of thin film transition liquid crystal display (TFT-LCD) optical waste glass applied in early-high-strength controlled low strength materials

Her-Yung Wang,Jyun-Sheng Chen 사단법인 한국계산역학회 2008 Computers and Concrete, An International Journal Vol.5 No.5

The present study verifies compressive strength, ultrasonic pulse velocity, electrical resistance, permeable ratio, and shrinkage from waste glass controlled low strength materials (WGCLSM) and earlyhigh-strength WGCSLM specimens, by replacing the sand with waste glass percentages of 0%, 10%, 20%, and 30%. This study reveals that increasing amounts of waste LCD glass incorporated into concrete increases WGCLSM fluidity and reduces the setting time, resulting in good working properties. By increasing the glass to sand replacement ratio, the compressive strength decreases to achieve low-strength effects. Furthermore, the electrical resistance also rises as a result of increasing the glass to sand replacement ratio. Early-high-strength WGCSLM aged 28 days has twice the electrical resistance compared to general WGCSLM. Early-high-strength WGCSLM aged 7 days has a higher ultrasonic pulse velocity similar to WGCSLM aged 28 days. The variation of length with age of different compositions is all within the tolerance range of 0.025%. This study demonstrates that the proper composition ratio of waste LCD glass to sand in early-high-strength WGCSLM can be determined by using different amounts of glass-sand. A mechanism for LCD optical waste glass usage can be established to achieve industrial waste minimization, resource recycling, and economic security.

수로설화에 나타난 가요의 신고찰

허영순(Yung Soon Her) 문창어문학회 1961 문창어문논집 Vol.2 No.-

Immunomodulating and Antitumor Activities of the Protein Fraction of Korean Mistletoe in Mice

Yung-Choon Yoo,Junglim Lee,Kyung Bok Lee,Erk Her,Jong-Bae Kim 한국실험동물학회 2006 Laboratory Animal Research Vol.22 No.4

Immunomodulating and antitumor activities of the protein fraction (KM-AS) isolated from Korean mistletoe (KM; Viscum album Coloratum) were investigated in mice. Treatment of KM-AS activated peritoneal macrophages to induce IL-1β in an in vitro experiment, and intravenous (i.v.) administration of KM-AS enhanced natural killer (NK) cell activity against Yac-1 NK-sensitive cells 2 days after administration. An i.v. administration of KM-AS (1 or 1.5 ㎍/mouse) 2 days before tumor inoculation significantly inhibited lung metastases of colon 26-M3.1 cells. The prophylactic effect of 1 ㎍/mouse of KM-AS on lung metastasis was almost the same with that of 100 ㎍/mouse of a water extract of KM (KM-110). Furthermore, multiple administrations of KM-AS given at 3 day-intervals after tumor inoculation led to a significant reduction of lung metastasis and suppression of the growth of B16-BL6 melanoma cells in a spontaneous metastasis model. These results suggest that KM-AS can activate NK cells and macrophages, and its immunomodulating activity contributes to the prophylactic as well as therapeutic inhibition of tumor metastasis.

지역사회 거주 조현병 환자의 음주에 영향을 미치는 요인: 서울 및 수도권의 주간재활시설을 중심으로

허원빈 ( Her Wonbin ),정은주 ( Jung Eun Ju ),최선영 ( Choi Sun Yung ),전종설 ( Chun Jong Serl ) 한국보건사회연구원 2013 保健社會硏究 Vol.33 No.3

본 연구의 목적은 지역사회 내에 거주하는 조현병 환자의 음주에 영향을 미치는 요인을 조사하는 것이다. 지역사회에 거주하며 서울 및 경기 지역에 위치한 주간재활시설인 사회복귀시설 16개소를 이용 중인 조현병 환자 총 258명을 대상으로 인구사회학적 요인, 심리적 요인, 정신질환적 요인들이 음주에 미치는 영향을 로지스틱 회귀분석을 실시 하여 검증하였다. 본 연구 결과에 따르면, 인구사회학적 요인중 남성 조현병 환자가 여성 환자에 비해 2.71배 음주 가능성이 높았으며, 사회복귀시설 이용기간이 길어질수록 음주 가능성이 낮아졌다. 이러한 연구결과는 지역사회에서 조현병 환자의 음주에 대한 스크리닝과 조기개입이 보다 적극적으로 이루어져야 하고, 특히 고 위험군인 남성 환자에 대해 주의를 기울여야 함을 시사하고 있다. The aim of this study is to investigate factors influencing drinking of patients with schizophrenia in community-based care. A total of 259 patients with schizophrenia from 16 daytime rehabilitation facilities in Seoul and Gyenggi areas participated in this study. Demographic factors, psychological factors, and psychiatric factors influencing drinking were investigated using logistic regression analysis. The study results showed that while males displayed higher drinking rate than females by factor of 2.71, the overall probability of drinking was lower for the patient with longer history of treatment in the daytime rehabilitation facilities. This result suggests the importance of early screening and treatment of alcohol problem in rehabilitation facilities, with special attention to male patients, who are at a higher risk.

Membrane/Electrode Interface Design for Effective Water Management in Alkaline Membrane Fuel Cells

Jang, Segeun,Her, Min,Kim, Sungjun,Jang, Jue-Hyuk,Chae, Ji Eon,Choi, Jiwoo,Choi, Mansoo,Kim, Sang Moon,Kim, Hyoung-Juhn,Cho, Yong-Hun,Sung, Yung-Eun,Yoo, Sung Jong American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.38

<P>The recent development of ultrathin anion exchange membranes and optimization of their operating conditions have significantly enhanced the performance of alkaline-membrane fuel cells (AMFCs); however, the effects of the membrane/electrode interface structure on the AMFC performance have not been seriously investigated thus far. Herein, we report on a high-performance AMFC system with a membrane/electrode interface of novel design. Commercially available membranes are modified in the form of well-aligned line arrays of both the anode and cathode sides by means of a solvent-assisted molding technique and sandwich-like assembly of the membrane and polydimethylsiloxane molds. Upon incorporating the patterned membranes into a single-cell system, we observe a significantly enhanced performance of up to ∼35% compared with that of the reference membrane. The enlarged interface area and reduced membrane thickness from the line-patterned membrane/electrode interface result in improved water management, reduced ohmic resistance, and effective utilization of the catalyst. We believe that our findings can significantly contribute further advancements in AMFCs.</P> [FIG OMISSION]</BR>

Poster Session : Activation of JNK, ERK and p38 MAPK by B chain from Korean mistletoe (Viscum Album Coloratum) Lectin

( Sun Mi Her ),( Woong Suk Yang ),( Ki Wook Kim ),( Seung Hoon Yang ),( Seong Kyu Song ),( Yung Choon Yoo ),( Jong Bae Kim ) 한국생화학분자생물학회 (구 한국생화학회) 2006 생화학분자생물학회 춘계학술발표논문집 Vol.2006 No.-

Prediction models of compressive strength and UPV of recycled material cement mortar

Chien-Chih Wang,Her-Yung Wang,Shu-Chuan Chang 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.19 No.4

With the rising global environmental awareness on energy saving and carbon reduction, as well as the environmental transition and natural disasters resulted from the greenhouse effect, waste resources should be efficiently used to save environmental space and achieve environmental protection principle of “sustainable development and recycling”. This study used recycled cement mortar and adopted the volumetric method for experimental design, which replaced cement (0%, 10%, 20%, 30%) with recycled materials (fly ash, slag, glass powder) to test compressive strength and ultrasonic pulse velocity (UPV). The hyperbolic function for nonlinear multivariate regression analysis was used to build prediction models, in order to study the effect of different recycled material addition levels (the function of Rm(F, S, G) was used and be a representative of the content of recycled materials, such as fly ash, slag and glass) on the compressive strength and UPV of cement mortar. The calculated results are in accordance with laboratory-measured data, which are the mortar compressive strength and UPV of various mix proportions. From the comparison between the prediction analysis values and test results, the coefficient of determination R2 and MAPE (mean absolute percentage error) value of compressive strength are 0.970-0.988 and 5.57-8.84%, respectively. Furthermore, the R2 and MAPE values for UPV are 0.960-0.987 and 1.52-1.74%, respectively. All of the R2 and MAPE values are closely to 1.0 and less than 10%, respectively. Thus, the prediction models established in this study have excellent predictive ability of compressive strength and UPV for recycled materials applied in cement mortar.

Predictive models of hardened mechanical properties of waste LCD glass concrete

Chien-Chih Wang,Her-Yung Wang,Chi Huang 사단법인 한국계산역학회 2014 Computers and Concrete, An International Journal Vol.14 No.5

This paper aims to develop a prediction model for the hardened properties of waste LCD glass that is used in concrete by analyzing a series of laboratory test results, which were obtained in our previous study. We also summarized the testing results of the hardened properties of a variety of waste LCD glass concretes and discussed the effect of factors such as the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. This study also applied a hyperbolic function, an exponential function and a power function in a non-linear regression analysis of multiple variables and established the prediction model that could consider the effect of the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. Compared with the testing results, the statistical analysis shows that the coefficient of determination R2 and the mean absolute percentage error (MAPE) were 0.930.96 and 5.48.4% for the compressive strength, 0.830.89 and 8.912.2% for the flexural strength and 0.870.89 and 1.82.2% for the ultrasonic pulse velocity, respectively. The proposed models are highly accurate in predicting the compressive strength, flexural strength and ultrasonic pulse velocity of waste LCD glass concrete. However, with other ranges of mixture parameters, the predicted models must be further studied.