107 research outputs found
Selective and potent small-molecule inhibitors of PI3Ks
No full textClass I PI3Ks are composed of four catalytic subunit variants (p110, p110, p110 and p110). The PI3K pathway is among the most frequently activated pathways in many diseases, and has emerged as an attractive target for drug development, in particular for the treatment of many human cancers including breast, prostate, ovarian, gastric, colon and hepatocellular cancers. One of the challenges in the discovery of drugs that target kinases is designing small-molecule inhibitors that are sufficiently selective to minimize off-target activity and reduce the risk of potential toxicity. This review explores the current landscape of PI3K-selective inhibitor development and highlights recent advances in achieving selectivity for PI3Ks over other protein kinases, with an emphasis on available structural information.101011sciescopu
An Approach to Assess Solder Interconnect Degradation Using Digital Signal
No full textDepartment of Human and Systems EngineeringDigital signals used in electronic systems require reliable data communication. It is necessary to monitor the system health continuously to prevent system failure in advance. Solder joints in electronic assemblies are one of the major failure sites under thermal, mechanical and chemical stress conditions during their operation. Solder joint degradation usually starts from the surface where high speed signals are concentrated due to the phenomenon referred to as the skin effect. Due to the skin effect, high speed signals are sensitive when detecting the early stages of solder joint degradation.
The objective of the thesis is to assess solder joint degradation in a non-destructive way based on digital signal characterization. For accelerated life testing the stress conditions were designed in order to generate gradual degradation of solder joints. The signal generated by a digital signal transceiver was travelling through the solder joints to continuously monitor the signal integrity under the stress conditions. The signal properities were obtained by eye parameters and jitter, which represented the characteristics of the digital signal in terms of noise and timing error. The eye parameters and jitter exhibited significant increase after the exposure of the solder joints to the stress conditions. The test results indicated the deterioration of the signal integrity resulted from the solder joint degradation, and proved that high speed digital signals could serve as a non-destructive tool for sensing physical degradation. Since this approach is based on the digital signals used in electronic systems, it can be implemented without requiring additional sensing devices. Furthermore, this approach can serve as a proactive prognostic tool, which provides real-time health monitoring of electronic systems and triggers early warning for impending failure.ope
An analysis of the impact of housing policies on housing prices in South Korea
No full textThe South Korean government has been intervening in the housing market for a long time to either activate or stabilize housing prices. However, there is a controversy about the effect of housing policy in South Korea. I analyzed the effect of housing policies as well as other factor s (interest rate, cost of renting, inflation, stock price, unemployment rate, exchange rate) on housing prices nationally as well as in northern Seoul and in southern Seoul, from January 2000 to January 2015 (181 months of data).
According to the results of my regression analysis to test the effect of housing policies, there is no statistical evidence that housing policies have effects on housing prices. The pattern is the same across all three estimation s (national, northern Seoul, southern Seoul). The attempt of the South Korean government to cool the overheated housing market never seems to have the desired negative effect. The efforts of the South Korean government to heat the depressed housing market never seems to have the intended positive effect, either. This research finds no useful effect of these policies.
Looking at other factors, the results are very similar across all three estimations (national, northern Seoul, southern Seoul). The cost of renting has a large, statistically significant positive effect in all cases. The unemployment rate has a large, statistically significant negative effect nationally. Both effects are larger in southern Seoul than in northern Seoul. The interest rate matters only in northern Seoul, while the stock prices matter only in southern Seoul. Less wealthy people live in northern Seoul, whereas wealthier people live in southern Seoul. Interest rates matter more to the former and stock prices matter more to the latter
Prognostics of Solder Joint Reliability Based on Impedance Analysis and Particle Filtering
No full text????????? ??????????????? ????????? ???????????? ??? ???????????? ???????????? ????????????
No full text
Improved Reliability Prediction Methodology for Electronic Packages Using RF Impedance Analysis
No full text
- …
