라이프미디어 서비스를 위한 라이프로깅 기법

김동칠(Dongchil Kim),양창모(Chang Mo Yang),송재종(Chai-Jong Song),박성주(Sungjoo Park) 대한전자공학회 2016 대한전자공학회 학술대회 Vol.2016 No.6

This paper proposes a automatic life logging scheme for life media services. The proposed scheme automatically collects various sensor data of a PC, a smartphone, home sensors, and wearable devices of users. It also converts forms of life log data into defined metadata and manages the user information.

Analysis of the effect of Rhodopseudomonas palustris on the lead exposure rat model using 1H-NMR-based metabolomics of urine and plasma

Chai Shutong,Zheng Ziyun,Liu Yani,Liang Yanhui,Yang Hong,Chen Jie,Bai Hongjuan,Yang Guan-e 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2

Background Rhodopseudomonas palustris had the eff ect of adsorbing and removing lead ions. Metabolomics is a comprehensive analysis based on several metabolites or biomarkers. Objective The paper aimed to investigate the restorative eff ect and the potential mechanisms of R. palustris in rats with the lead exposure model using 1 H-NMR metabolomics. Results Nine endogenous metabolites from rat plasma and 13 endogenous metabolites from rat urine were identifi ed as potential biomarkers of the symptoms of lead poisoning. The changes of metabolites levels in the plasma included lower levels of valine, acetoacetate, and N-acetyl-glycoprotein and a higher concentration of lactate, acetate, creatine, threonine, glutamine, and asparagine in model group compared with control group. Furthermore, increased citrate, succinate, dimethylamine, pyruvate, acetoacetate, α -oxoglutarate and asparagine, accompanied by decreased LDL/VLDL, taurine, creatinine, glucose and hippurate levels were observed in the model group compared with the control group in the urine. Biochemical parameters and histopathology examination dovetailed well with the metabolomics data. Treatment with R. palustris at a certain degree returned the levels of these metabolites to normal levels. Plasma and urine metabolomic analysis showed changes associated with energy metabolism, amino acids and fatty acid metabolism of lead exposure rats. Conclusion The eff ects of removing lead ions of R. palustris in rats with lead exposure were confi rmed. This research demonstrated that 1 H-NMR-based metabolomics was a promising tool to identify potential biomarkers and unravel protective eff ect mechanisms of R. palustris in lead poisoning rats.

Nanoscale Bipolar and Complementary Resistive Switching Memory Based on Amorphous Carbon

Yang Chai,Yi Wu,Takei, Kuniharu,Hong-Yu Chen,Shimeng Yu,Chan, Philip C. H.,Javey, Ali,Wong, H.-S Philip IEEE 2011 IEEE transactions on electron devices Vol.58 No.11

<P>There has been a strong demand for developing an ultradense and low-power nonvolatile memory technology. In this paper, we present a carbon-based resistive random access memory device with a carbon nanotube (CNT) electrode. An amorphous carbon layer is sandwiched between the fast-diffusing top metal electrode and the bottom CNT electrode, exhibiting a bipolar switching behavior. The use of the CNT electrode can substantially reduce the size of the active device area. We also demonstrate a carbon-based complementary resistive switch (CRS) consisting of two back-to-back connected memory cells, providing a route to reduce the sneak current in the cross-point memory. The bit information of the CRS cell is stored in a high-resistance state, thus reducing the power consumption of the CRS memory cell. This paper provides valuable early data on the effect of electrode size scaling down to nanometer size.</P>

Motor speed signature analysis of bearing fault detection based on SK and adaptive signal reconstruction with EEMD

Chai Na,Yang Ming,Ren Boyang,Xu Dianguo 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Local bearing faults will lead to impulses in motor speed which is already available in the vector controlled AC motor drives. Due to the limited sampling frequency of control system, the extraction of fault feature is difficult. Therefore, a signal processing scheme which combines spectral kurtosis (SK) with the adaptive signal reconstruction based on ensemble empirical mode decomposition (EEMD) is proposed. Firstly, motor speed is decomposed by EEMD into a finite number of intrinsic mode functions (IMFs) which reflect the local characteristics of original signal. Then, the correlation coefficient is employed to eliminate the irrelevant components, and reconstruct the speed signal with a higher signal-to-noise ratio adaptively. Finally, the reconstructed speed is analyzed with SK to extract fault features. The proposed scheme is verified on the motor bearing outer ring fault detection platform, and its effectiveness over the conventional SK is also shown.

Hypolipidemic Effect of a Blue-Green Alga (Nostoc commune) Is Attributed to Its Nonlipid Fraction by Decreasing Intestinal Cholesterol Absorption in C57BL/6J Mice

Chai Siah Ku,김보경,Tho X. Pham,Yue Yang,CurtisL.Weller,Timothy P. Carr,박영기,이지영 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.11

We previously demonstrated that Nostoc commune var. sphaeroids Ku¨tzing (NO), a blue-green alga (BGA), exerts a hypolipidemic effect in vivo and its lipid extract regulates the expression of genes involved in cholesterol and lipid metabolism in vitro. The objective of this study was to investigate whether the hypolipidemic effect of NO is attributed to an algal lipid or a delipidated fraction in vivo compared with Spirulina platensis (SP). Male C57BL/6J mice were fed an AIN-93M diet containing 2.5% or 5% of BGA (w/w) or a lipid extract equivalent to 5% of BGA for 4 weeks to measure plasma and liver lipids, hepatic gene expression, intestinal cholesterol absorption, and fecal sterol excretion. Plasma total cholesterol (TC) was significantly lower in 2.5% and 5% NO-fed groups, while plasma triglyceride (TG) levels were decreased in the 5% NO group compared with controls. However, neither NO organic extract (NOE) nor SP-fed groups altered plasma lipids. Hepatic mRNA levels of sterol regulatory element-binding protein 2, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), carnitine palmitoyltransferase-1α, and acyl-CoA oxidase 1 were induced in 5% NO-fed mice, while there were no significant changes in hepatic lipogenic gene expression between groups. NO, but not NOE and SP groups, significantly decreased intestinal cholesterol absorption. When HepG2 cells and primary mouse hepatocytes were incubated with NOE and SP organic extract (SPE), there were marked decreases in protein levels of HMGR, low-density lipoprotein receptor, and fatty acid synthase. In conclusion, the nonlipid fraction of NO exerts TC and TG-lowering effects primarily by inhibiting intestinal cholesterol absorption and by increasing hepatic fatty acid oxidation, respectively.

Porting A Client Agent For Pitch Estimation and Noise Suppression To An Embedded Multi Processor

Chai-Jong Song,Chang-Mo Yang,Seok-Pil Lee,Kyung-Hack Seo 한국멀티미디어학회 2011 한국멀티미디어학회 국제학술대회 Vol.2011 No.-

This paper is to implement contents based music retrieval method on the embedded digital signal processor (DSP) chipset. This method is basically Query by Humming and Singing (QbSH) with polyphonic music signal. The client has to extract the feature and suppress the noise from user humming signal recorded with input device. Noise suppression algorithm makes merge of Minimum Statistics (MS) for stationary noise and Improved Minima Controlled Recursive Averaging (IMCRA) for non￢stationary noise, and the feature is estimated with temporal and spectral autocorrelation simultaneously to reduce the pitch having and doubling problem. We develop the prototypes of clients for three different platforms like computer, smart phone/pad and KARAOKE. The client part of this system is ported on the DSP chipset which is the TI OMAP processor named L138 including C674x core up to 300㎒ clock cycle for DSP part and ARM-9 core up to 600㎒ clock cycle.

Implementation of a personalized second TV platform

Chai-Jong Song,Chang-Mo Yang,Seok-Pil Lee,Kyung-Hack Seo 한국멀티미디어학회 2011 한국멀티미디어학회 국제학술대회 Vol.2011 No.-

This paper describes the implementation of a personalized second TV with encoding contents of broadcasting and local Media. The concept of this system is relaying the contents which are received from any media source including not only terrestrial, cable and satellite like any kind of media as broadcasting but also stand-alone media players like DVD, VCR, and so on to user over the network using RTP and TRSP media stream protocol. We have developed a personalized second TV and implemented it to a stand-alone type device. For this purpose we have utilized the H.264 encoder to convert contents from analog to digital. It streams the encoded contents to users over internet with RTP and RTSP protocols. We also have developed a state-of-the-art streaming server and client player which can work seamless reconnection with other clients consecutively, and that can manage transmit rate along the status of the internet to satisfy QoS.

Radiotherapy for pituitary adenomas

Chai Hong Rim,Dae Sik Yang,Young Je Park,Won Sup Yoon,Jung Ae Lee,Chul Yong Kim 대한방사선종양학회 2011 Radiation Oncology Journal Vol.29 No.3

Purpose: To evaluate long-term local control rate and toxicity in patients treated with external beam radiotherapy (EBRT) for pituitary adenomas. Materials and Methods: We retrospectively reviewed the medical records of 60 patients treated with EBRT for pituitary adenoma at Korea University Medical Center from 1996 and 2006. Thirty-five patients had hormone secreting tumors, 25 patients had non-secreting tumors. Fifty-seven patients had received postoperative radiotherapy (RT), and 3 had received RT alone. Median total dose was 54 Gy (range, 36 to 61.2 Gy). The definition of tumor progression were as follows: evidence of tumor progression on computed tomography or magnetic resonance imaging, worsening of clinical sign requiring additional operation or others, rising serum hormone level against a previously stable or falling value, and failure of controlling serum hormone level so that the hormone level had been far from optimal range until last follow-up. Age, sex, hormone secretion, tumor extension, tumor size, and radiation dose were analyzed for prognostic significance in tumor control. Results: Median follow-up was 5.7 years (range, 2 to 14.4 years). The 10-year actuarial local control rates for non-secreting and secreting adenomas were 96% and 66%, respectively. In univariate analysis, hormone secretion was signifi cant prognostic factor (p = 0.042) and cavernous sinus extension was marginally signifi cant factor (p = 0.054) for adverse local control. All other factors were not signifi cant. In multivariate analysis, hormone secretion and gender were signifi cant. Fifty-three patients had mass-effect symptoms (headache, dizziness, visual disturbance, hypopituitarism, loss of consciousness, and cranial nerve palsy). A total of 17 of 23 patients with headache and 27 of 34 patients with visual impairment were improved. Twenty-seven patients experienced symptoms of endocrine hypersecretion (galactorrhea, amenorrhea, irregular menstruation, decreased libido, gynecomastia, acromegaly, and Cushing’s disease). Amenorrhea was abated in 7 of 10 patients, galactorrhea in 8 of 8 patients, acromegaly in 7 of 11 patients, Cushing’s disease in 4 of 4 patients. Long-term complication was observed in 4 patients; 3 patients with cerebrovascular accident, 1 patient developed dementia. Of these patients, 3 of 4 received more than 60 Gy of irradiation. Conclusion: EBRT is highly effective in preventing recurrence and reducing mass effect of non-secreting adenoma. Effort to improve tumor control of secreting adenoma is required. Careful long-term follow-up is required when relatively high dose is applied. Modern radiosurgery or proton RT may be options to decrease late complications.

Intrinsic ferroelectric polarization of orthorhombic manganites withE-type spin order

Chai, Y. S.,Oh, Y. S.,Wang, L. J.,Manivannan, N.,Feng, S. M.,Yang, Y. S.,Yan, L. Q.,Jin, C. Q.,Kim, Kee Hoon American Physical Society 2012 Physical review. B, Condensed matter and materials Vol.85 No.18

Blue-Green Algae Inhibit the Development of Atherosclerotic Lesions in Apolipoprotein E Knockout Mice

Chai Siah Ku,김보경,Tho X. Pham,Yue Yang,Casey J. Wegner,박영기,Marcy Balunas,이지영 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.12

Hyperlipidemia and inflammation contribute to the development of atherosclerotic lesions. Our objective was to determine antiatherogenic effect of edible blue-green algae (BGA) species, that is, Nostoc commune var. sphaeroides Ku¨tzing (NO) and Spirulina platensis (SP), in apolipoprotein E knockout (ApoE-/-) mice, a well-established mouse model of atherosclerosis. Male ApoE-/- mice were fed a high-fat/high-cholesterol (HF/HC, 15% fat and 0.2% cholesterol by wt) control diet or a HF/HC diet supplemented with 5% (w/w) of NO or SP powder for 12 weeks. Plasma total cholesterol (TC) and triglycerides (TG) were measured, and livers were analyzed for histology and gene expression. Morphometric analysis for lesions and immunohistochemical analysis for CD68 were conducted in the aorta and the aortic root. NO supplementation significantly decreased plasma TC and TG, and liver TC, compared to control and SP groups. In the livers of NO-fed mice, less lipid droplets were present with a concomitant decrease in fatty acid synthase protein levels than the other groups. There was a significant increase in hepatic low-density lipoprotein receptor protein levels in SP-supplemented mice than in control and NO groups. Quantification of aortic lesions by en face analysis demonstrated that both NO and SP decreased aortic lesion development to a similar degree compared with control. While lesions in the aortic root were not significantly different between groups, the CD68-stained area in the aortic root was significantly lowered in BGA-fed mice than controls. In conclusion, both NO and SP supplementation decreased the development of atherosclerotic lesions, suggesting that they may be used as a natural product for atheroprotection.