이유민 교수

Inhaled corticosteroids (ICS) might reduce the risk of lung cancer by controlling airway inflammation in patients with chronic obstructive pulmonary disease (COPD) because both are associated with chronic inflammation. The objective was to assess the impact of ICS on lung cancer risk reduction in COPD patients. We performed a nested case-control study based on the database of the National Health Insurance Service-National Sample Cohort, a nationally representative cohort of 1,125,691 participant

The results of this study suggest that environmental exposure to cadmium may alter the AMH level of premenopausal women, depending on their age group.

Abstract We investigated the effects of particulate matter (PM) on mortality in patients diagnosed with asthma-COPD overlap (ACO) or ‘pure COPD’. Subjects from the National Health Insurance Service–National Sample Cohort of Korea, who were aged 40 years or above and had newly diagnosed COPD since 2009 were selected. Finally, 6,313 patients were enrolled and divided into ‘pure COPD’ and ACO groups. Average PM 10 exposure data were obtained using Kriging interpolation from 2001 to 2013. Hazard rat

The soaring clocking frequency and integration density demand robust and stable power delivery to support tens of millions of transistors switching. To ensure the design quality of power delivery, extensive transient power grid simulations need to be performed during design process. However, the traditional circuit simulation engines are not scaled as well as the complexity of power delivery, as a result, it often takes a long runtime and huge memory requirement to simulate a medium size power g

In this work, a hierarchical bin-based legalization approach, HiBinLegalizer, is developed to legalize standard cells with minimal movement. First, a chip is divided into several bins with equal size. Then, starting with the most crowed unlegalized bin, a merging procedure for bins is used to integrate bins into a cross-shape region or a square-shape region until the cell density in that region is less than a specific cell-density-threshold. After that, an efficient legalization method which sim

To sustain Moore's law, three-dimensional integrated circuit (3-D IC) is a promising solution to achieve high performance and low cost targets. However, its operating temperature is higher than that of a 2-D IC because of its high power density of stacked dies and ill of heat dissipation capability. Therefore, on-chip thermal effects have become major concerns of 3-D ICs. Utilizing look-up table approach, this paper, LUTSim, provides two thermal simulation engines, I-LUTSim and S-LUTSim, to effi

This work provides an efficient statistical electrothermal simulator for analyzing on-chip thermal reliability under process variations. Using the collocation-based statistical modeling technique, first, the statistical interpolation polynomial for on-chip temperature distribution can be obtained by performing deterministic electrothermal simulation very few times and by utilizing polynomial interpolation. After that, the proposed simulator not only provides the mean and standard deviation profi

By combining analytical and numerical simulation techniques, this work develops a hybrid thermal simulator, NUMANA, which can effectively deal with complicated material structures, to estimate the temperature profile of a 3-D IC. Compared with a commercial tool, ANSYS, its maximum relative error is only 1.84%. Compared with a well known linear system solver, SuperLU [1], it can achieve orders of magnitude speedup.

In this work, a hierarchical bin-based legalization approach, HiBinLegalizer, is developed to legalize standard cells with minimal movement. First, a chip is divided into several bins with equal size. Then, starting with the most crowed unlegalized bin, a merging procedure for bins is used to integrate bins into a cross-shape region or a square-shape region until the cell density in that region is less than a specific cell-density-threshold. After that, an efficient legalization method which sim

Abstract This paper presents a compact thermal model for smartphones, Phone‐nomenon 2.0, to predict the thermal behavior of smartphones. In the beginning, non‐linearities of internal and external heat transfer mechanisms of smartphones and a compact thermal model for these non‐linearities have been studied and proposed. Then, an iterative simulation procedure to handle these non‐linearities was developed, and the basic simulation framework which is one option in Phone‐nomenon 2.0 was established

By combining analytical and numerical simulation techniques, this work develops a hybrid thermal simulator, NUMANA, which can effectively deal with complicated material structures, to estimate the temperature profile of a 3-D IC. Compared with a commercial tool, ANSYS, its maximum relative error is only 1.84%. Compared with a well known linear system solver, SuperLU [1], it can achieve orders of magnitude speedup.

Delay, power, skew, area and sensitivity are the most important concerns in current clock‐tree design. We present in this paper an algorithm for simultaneously optimizing the above objectives by sizing wires and buffers in clock trees. Our algorithm, based on Lagrangian relaxation method, can optimally minimize delay, power and area simultaneously with very low skew and sensitivity. With linear storage overall and linear runtime per iteration , our algorithm is extremely economical, fast and acc

The rising power consumption and clock frequency of VLSI technology demand robust and stable power delivery. Extensive transient simulations on large scale power delivery structures are required to analyze power delivery fluctuation caused by dynamic IR-, and Ldi/dt drop as well as package and on-chip resonance. This paper develops a novel and efficient transient simulation algorithm for the power distribution networks. The 3D TLM-ADI (Transmission-Line-Modeling Alternating-Direction-Implicit) m