Monte Carlo Method and Quantile Regression for Uncertainty Analysis of Wind Power Forecasting Based on Chaos-LS-SVM

Xin Zhao,Chao Ge,Fangfang Ji,Yajuan Liu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.11

In the paper, the chaos least squares support vector machine algorithm (Chaos-LS-SVM) is applied. To conduct uncertainty analysis of wind power forecasting, two forecasting algorithms of the probabilistic uncertainty analysis based on the Monte Carlo method and the quantile regression analysis based on Chaos-LS-SVM are discussed. The effectiveness and superiority of the two uncertainty analysis methods in the confidence level of 95%, 90%, and 85% are discussed by simulation analysis, and the confidence interval is given in the corresponding confidence level. The prediction interval coverage probability (PICP) and the prediction interval normalized average width (PINAW) of the two uncertainty methods are compared. In the time scale of 1h-ahead, 4h-ahead, and 6h-ahead, the probabilistic uncertainty analysis based on the Monte Carlo method is suitable. In the time scale of 24h-ahead, the quantile regression analysis based on Chaos-LS-SVM is superior.

Chaotic Dynamics of a Three-phase Clock-driven Oscillator with Dual Voltage Controllability

Ji Chao Zhou,송한정 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.8

In this work, we study a novel dual voltage controlled chaotic oscillator using a three-phase clock. The chaotic oscillator is based on two nonlinear functions which are needed for chaotic signal generation. The proposed chaotic circuit consists of non-overlapping clock driven three MOS (Metal Oxide Semiconductor) switches for S/H (sample and hold), a level shifter and two nonlinear functions for nonlinearity in the feedback. After optimizing of nonlinear functions for chaotic signal generation, the proposed circuit was simulated with SPICE (Simulation Program with Integrated Circuit Emphasis) program using a 0.6 um CMOS (complementary metal oxide semiconductor) process parameter. For various control voltages, its chaotic dynamics such as time waveform, bifurcation diagram and state transition diagram were analyzed. We confirmed that the circuit can generate discrete chaotic signals in specific control voltages. This circuit expected to be utilized for various chaos applications.

YAP/TAZ-Mediated Upregulation of GAB2 Leads to Increased Sensitivity to Growth Factor–Induced Activation of the PI3K Pathway

Wang, Chao,Gu, Chao,Jeong, Kang Jin,Zhang, Dong,Guo, Wei,Lu, Yiling,Ju, Zhenlin,Panupinthu, Nattapon,Yang, Ji Yeon,Gagea, Mihai (Mike),Ng, Patrick Kwok Shing,Zhang, Fan,Mills, Gordon B. American Association for Cancer Research 2017 Cancer Research Vol.77 No.7

<P>Interactions between HIPPO, YAP/TAZ, and the PI3K/AKT pathway may be therapeutically targetable, providing new approaches to treating endometrial cancers and other cancers where the HIPPO pathway is a core oncogenic driver.</P><P>The transcription regulators YAP and TAZ function as effectors of the HIPPO signaling cascade, critical for organismal development, cell growth, and cellular reprogramming, and YAP/TAZ is commonly misregulated in human cancers. The precise mechanism by which aberrant YAP/TAZ promotes tumor growth remains unclear. The HIPPO tumor suppressor pathway phosphorylates YAP and TAZ, resulting in cytosolic sequestration with subsequent degradation. Here, we report that the PI3K/AKT pathway, which is critically involved in the pathophysiology of endometrial cancer, interacts with the HIPPO pathway at multiple levels. Strikingly, coordinate knockdown of YAP and TAZ, mimicking activation of the HIPPO pathway, markedly decreased both constitutive and growth factor–induced PI3K pathway activation by decreasing levels of the GAB2 linker molecule in endometrial cancer lines. Furthermore, targeting YAP/TAZ decreased endometrial cancer tumor growth <I>in vivo</I>. In addition, YAP and TAZ total and phosphoprotein levels correlated with clinical characteristics and outcomes in endometrial cancer. Thus, YAP and TAZ, which are inhibited by the HIPPO tumor suppressor pathway, modify PI3K/AKT pathway signaling in endometrial cancer. The cross-talk between these key pathways identifies potential new biomarkers and therapeutic targets in endometrial cancer. <I>Cancer Res; 77(7); 1637–48. ©2017 AACR</I>.</P>

폐경기 중년여성의 운동 참여 효과 검증

우계초(Ji Chao Niu),장명재(Myoung Jei Chang),이신언(Shin Eon Lee),최희연(Hee Yeon Choi) 한국사회체육학회 2012 한국사회체육학회지 Vol.0 No.49

Physical activity is known to reduce risk of early death through reduction of risk of metabolic syndrome, prevention of weight gain, reduction of abdominal obesity, and increment of bone density. Despite the presence of some physical activity guidelines, a lot of people have been conduct physical activity by their own standards. In the present study, the effects of physical activity that based on arbitrary criteria on the obesity and osteoporosis were investigated. 64 volunteers, who aged over 40 and under 50, were participated. And they were divided into four subgroups(menstruation without exercise, menstruation with exercise, postmenopause without exercise, postmenopause with exercise) to determine the participation of physical activity and menstrual status. In the present results, statistically significant differences occurred in %Fat, abdominal fat ratio, visceral fat area, despite no statistical differences in body mass index in each groups. % Fat, abdominal fat ratio, visceral fat area was increased significantly by menopause, however, physical activity showed the opposite effects. In the blood analysis results were not statistically significant difference occurred. Regression analysis results on visceral fat area showd that age, body mass index, w·aist circumference, triglyceride levels have been identified as a statistically significant, and menstruation showd that T-score and Z-score levels have been identified as a statistically significant. Base on the results of present study, it is suggested that physical activity that conducted by the arbitrary criteria in women after menopause showed positive effects on abdominal fat, and osteoporosis, however for the more obvious effects, increasing calorie consumption and frequency of participation is desirable.

급속 충전에서 탱크 내부의 수소 온도 변화에 관한 이론 연구

이길초(JI-CHAO LI),이길강(JI-QIANG LI),허항(HENG XU),최병철(BYUNG CHUL CHOI),권정태(JEONG-TAE KWON) 한국수소및신에너지학회 2023 한국수소 및 신에너지학회논문집 Vol.34 No.6

The fast filling process of high-pressure hydrogen has an important impact on the filling efficiency and safety. In this paper, a specific study is carried out on the thermophysical phenomena during the fast filling process. Starting from the gas state equation of hydrogen, the change law of the hydrogen storage temperature is obtained, and then the temperature rise prediction is constructed. The model can clarify the relationship between the filling parameters and the temperature rise during the fast filling process, thereby revealing the flow and heat transfer laws of the fast charging process. To improve the theoretical research basis for the evaluation of vehicle-mounted hydrogen fast charging capacity, temperature prediction and optimization of hydrogenation methods.

가정용 소형 제습로터의 성능에 대한 실험적 연구

한기초(Han, Ji-Chao),김내현(Kim, Nae-Hyun) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.4

여름철이 고온 다습한 우리나라에서는 잠열부하가 크기 때문에 에어컨만을 사용하면 냉방에너지를 많이 사용하게 된다. 이 때에 제습기를 동시에 사용하면 냉방 중 큰 비중을 차지하는 잠열부하를 줄일 수 있어 실내 공기질도 개선하고 냉방에너지도 절약할 수 있다. 본 연구에서는 가정용 제습기에 사용되는 무기섬유 기질에 메탈 실리케이트가 함침된 소형 제습 로터에 대하여 항온항습실에서 로터 회전속도, 재생 공기온도, 실내 공기온도, 실내 상대습도, 제습부 전방풍속을 변화 시키며 제습 성능을 측정하였다. 제습 로터는 최적 회전수 (1.0rpm)가 존재하며 최적치를 초과하면 불완전 재생 등으로 제습 량이 급격히 감소한다. 재생온도가 높아질수록 재생에는 유리하나 제습-재생과정의 열적인 편차가 급격히 증가하여 제습량 이 감소한다. 따라서 최적 재생온도가 존재하는데 본 연구의 경우는 100oC로 나타났다. 상대습도의 증가에 따라 제습량도 증가한다. 이는 제습제의 제습능력이 상대습도에 의존하는 때문이다. 실내 공기온도의 증가에 따라 제습량도 증가한다. 이는 제습측 온도가 높을 때 재생측 공기와의 열적 편차가 감소하여 제습부의 상당량이 제습에만 사용될 수 있기 때문이다. 전방 풍속의 증가에 따라 제습량도 증가한다. 이는 전방풍속의 증가에 따라 열 및 물질전달계수가 증가하기 때문이다. In Korea, summer is hot and humid, and air-conditioners consume too much electricity due to large amount of latent heat. Simultaneous usage of dehumidifier may reduce the latent heat and save the electricity. In this study, dehumidification performance was measured in a constant temperature and humidity chamber for a small-sized dehumdification rotor made of inorganic fiber impregnated with metallic silicate. Variables were rotor speed, room temperature, regeneration temperature, room relative humidity and frontal velocity to the rotor. Results showed that there existed optimum rotor speed (1.0 rpm), and optimum regeneration temperature (100oC). Above the optimum rotor speed, incomplete regeneration is responsible for reduced dehumidification. Above the optimum regeneration temperature, increased temperature difference between regeneration and dehumidification process is responsible for reduced dehumidification. The amount of dehumidification also increases with the increase of relative humidity, dehumidification temperature and flow velocity into the rotor.

GAS-SOLID SUSPENSION FLOWS WITH HYDRODYNAMIC AND THERMODYNAMIC NON-EQUILIBRIUM

Chao Liu,Hong Ji Shu 대한기계학회 1992 International Conference on Fluid Machinery Vol.1 No.1

Shear behavior of reinforced HPC beams made of a low cement content without shear reinforcements

Chao-Wei Tang,Yu-Ping Chen,How-Ji Chen,Chung-Ho Huang,Tsang-Hao Liu 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.11 No.1

High-performance concrete (HPC) usually has higher paste and lower coarse aggregate volumes than normal concrete. The lower aggregate content of HPC can affect the shear capacity of concrete members due to the formation of smooth fractured surfaces and the subsequent development of weak interface shear transfer. Therefore, an experimental investigation was conducted to study the shear strength and cracking behavior of full-scale reinforced beams made with low-cement-content high-performance concrete (LcHPC) as well as conventional HPC. A total of fourteen flexural reinforced concrete (RC) beams without shear reinforcements were tested under a two-point load until shear failure occurred. The primary design variables included the cement content, the shear span to effective depth ratio (a/d), and the tensile steel ratio (ρw). The results indicate that LcHPC beams show comparable behaviors in crack and ultimate shear strength as compared with conventional HPC beams. Overall, the shear strength of LcHPC beams was found to be larger than that of corresponding HPC beams, particularly for an a/d value of 1.5. In addition, the crack and ultimate shear strength increased as a/d decreased or ρw increased for both LcHPC beams and HPC beams. This investigation established that LcHPC is recommendable for structural concrete applications.

Effects of Myogenin on Expression of Late Muscle Genes through MyoD-Dependent Chromatin Remodeling Ability of Myogenin

Chao Du,Ju-Hua Ni,Ya-Qiong Jin,Jun-Juan Qi,Zhen-Xing Ji,Shu-Yan Li,Guo-Shun An,Hong-Ti Jia 한국분자세포생물학회 2012 Molecules and cells Vol.34 No.2

MyoD and myogenin (Myog) recognize sets of distinct but overlapping target genes and play different roles in skeletal muscle differentiation. MyoD is sufficient for near-full expression of early targets, while Myog can only partially enhance expression of MyoD-initiated late muscle genes. However, the way in which Myog enhances the expression of MyoD-initiated late muscle genes remains unclear. Here, we examine the effects of Myog on chromatin remodeling at late muscle gene promoters and their activation within chromatin environment. Chromatin immunoprecipitation (ChIP) assay showed that Myog selectively bound to the regulatory sequences of late muscle genes. Overexpres-sion of Myog was found to overcome sodium butyrate-inhibited chromatin at late muscle genes in differ-entiating C2C12 myoblasts, shifting the transcriptional activation of these genes to an earlier time period. Furthermore, overexpression of Myog led to increased hyperacetylation of core histone H4 in differentiating C2C12 myoblasts but not NIH3T3 fibroblasts, and hyperacetylated H4 was associated directly with the late muscle genes in differentiating C2C12, indicating that Myog can induce chromatin remodeling in the presence of MyoD. In addition, co-immunopre-cipitation (CoIP) revealed that Myog was associated with the nuclear protein Brd4 in differentiating C2C12 myoblasts. Together, these results suggest that Myog enhances the expression of MyoD-initiated late muscle genes through MyoD-dependent ability of Myog to induce chromatin remodeling, in which Myog-Brd4 interaction may be involved.

Poster Session 2 : Oral Presentation ; Neurobiology : Characterization of a ternary complex with neurotrophin receptors and an ankyrin-rich membrane spanning protein

( Ji Hee Yu ),( Mi Kyoung Son ),( Jung Sun Cho ),( Han Jeong Park ),( Seung Pyo Lee ),( Ki Suk Paik ),( Moses V. Chao ),( Mi Sook Chang ) 한국생화학분자생물학회 (구 한국생화학회) 2005 62회 KSBMB Annual Meeting in 2005 Vol.- No.-