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In this study, we developed a deep neural network (DNN) model with weight correlation descent (WCD) regularization to improve polygenic risk score predictions for complex diseases, specifically gender-specific cancers, using the UK Biobank dataset. Our DNN model with WCD outperformed both conventional PRS models and DNN models without WCD, demonstrating the importance of regularization techniques in enhancing model performance and capturing non-linear effects and interactions in genomic data. These findings contribute to a better understanding of genetic architecture, facilitating personalized interventions based on individual genetic profiles and ultimately benefiting patient care and health outcomes.

We consider a matching model of employment with wages that are flexible for new hires, but sticky within matches. We depart from standard treatments of sticky wages by allowing worker effort to respond to the wage being too high or low, rendering the effective wage (wage divided by output) more flexible. Shimer (2004), Pissarides (2009), and others have illustrated that employment in the Mortensen-Pissarides model does not depend on the degree of wage flexibility in existing matches. But this is not true in our model. If wages of matched workers are stuck too high in a recession, then firms will require they provide more effort. In turn, this lowers the value of additional labor, reducing new hiring.

The standard models with incomplete markets (e.g. Aiyagari) have difficulty justifying the current income tax rates as an optimal or political equilibrium outcome. Given the highly skewed income distribution, the majority of the population would be in favor of raising taxes to a much higher level. We show that incorporating (i) the ex-ante heterogeneity of earnings and (ii) income-dependent voting behavior helps us to reconcile the large gap between the model and data.

We study business cycle fluctuations in heterogeneous agent general equilibrium models featuring intensive and extensive margins of labor supply. A nonlinear mapping from time devoted to work to labor services generates operative extensive and intensive margins. Our model captures the salient features of the empirical distribution of hours worked, including how individuals transit within this distribution. We study how various specifications influence labor supply responses to aggregate technology shocks and find that abstracting from intensive margin adjustment can have large effects on the volatility of aggregate hours even if fluctuations along the intensive margin are small.

We develop a quantitative heterogeneous-agents general equilibrium model that reproduces the income inequalities of 32 countries in the Organization for Economic Co-operation and Development. Using this model, we compute the optimal income tax progressivity and redistribution for each country under the equal-weight utilitarian social welfare function. A policy reform to adopt the optimal progressivity is supported by the majority of the population. Finally, we uncover the Pareto weights in the social welfare functions of each country that justify the current redistribution policy.

Bils, Chang, and Kim(2017) show that when effrot can respond, the sticky wages of existing job can affect hiring, despite wages of new hires being flexible. We confirm this result in an alternative wage setting ― Taylor type staggering contract. If wages of matched workers are stuck too high in a recession, firms will require more effort, lowering the value of additional labor and reducing new hiring.

In this paper, we have studied a removing method of exponentially decaying DC offset by deep learning approach. Since conventional FIR filter is ineffective when time constant is predicted imprecisely, the main goal of this research was to make a deep neural network (DNN) that has adaptability to imprecise time constants. For the implementation of DNN, we used Tensorflow deep learning library with python language. Stochastic gradient descent (SGD) method was adopted for training algorithm, and the training dataset used for training was generated by the theoretical equation of the exponentially decaying DC offset. After training process, the performance test was conducted using the PSCAD/EMTDC output as test data. The results are compared with the conventional FIR filter, and it was confirmed that DNN has better characteristics for imprecise time constants compared to the FIR filter.

Standard heterogeneous agent macro models that highlight idiosyncratic productivity shocks do not generate the near zero cross-sectional correlation between hours and wages found in the data. We ask whether matching this moment matters for business cycle properties of these models. To do this we explore two extensions of the model in Chang et al. (2019) that can match this empirical cross-section correlation. One of these departs from the assumption of balanced growth preferences. The other introduces an idiosyncratic shock to the opportunity cost of market work that is highly correlated with the shock to market productivity. While both extensions can match the empirical correlation, they have large and opposing effects on the cyclical volatility of the labor market. We conclude that the cross-sectional moment is important for business cycle analysis and that more work is needed to distinguish the potential mechanisms that can generate it.

At the aggregate level, the labor supply elasticity can significantly depart from the micro elasticity. In an economy where households make decisions on the labor market participation, the slope of the aggregate labor supply curve is determined by the distribution of reservation wages rather than by the willingness to substitute leisure intertemporally. We present a model economy where earnings and wealth distributions are comparable to those in the micro data. We find that the aggregate labor supply elasticity of such an economy is around 1, which is greater than the typical micro estimates but smaller than those often assumed in the aggregate models. Our model also sheds some light on the recent debate on the failure of the representative agent model.

Monopiles have been most widely used for supporting offshore wind turbines (OWTs) in shallow water areas. However, multi-member lattice-type structures such as jackets and tripods are also considered good alternatives to monopile foundations for relatively deep water areas with depth ranging from 25-50 m owing to their technical and economic feasibility. Moreover, jacket structures have been popular in the oil and gas industry for a long time. However, several unsolved technical issues still persist in the utilization of multi-member lattice-type supporting structures for OWTs; these problems include pile-soil-interaction (PSI) effects, realization of dynamically stable designs to avoid resonances, and quick and safe installation in remote areas. In this study, the effects of PSI on the dynamic properties of bottom-fixed OWTs, including monopile-, tripod- and jacket-supported OWTs, were investigated intensively. The tower and substructure were modeled using conventional beam elements with added mass, and pile foundations were modeled with beam and nonlinear spring elements. The effects of PSI on the dynamic properties of the structure were evaluated using Monte Carlo simulation considering the load amplitude, scouring depth, and the uncertainties in soil properties.

Standard heterogeneous agent macro models that highlight idiosyncratic productivity shocks do not generate the near zero cross-sectional correlation between hours and wages found in the data. We ask whether matching this moment matters for business cycle properties of these models. To do this we explore two extensions of the model in Chang et al. (2019) that can match this empirical cross-section correlation. One of these departs from the assumption of balanced growth preferences. The other introduces an idiosyncratic shock to the opportunity cost of market work that is highly correlated with the shock to market productivity. While both extensions can match the empirical correlation, they have large and opposing effects on the cyclical volatility of the labor market. We conclude that the cross-sectional moment is important for business cycle analysis and that more work is needed to distinguish the potential mechanisms that can generate it.

We develop a heterogeneous-agent general equilibrium model that incorporates both intensive and extensive margins of labor supply. A nonconvexity in the mapping between time devoted to work and labor services distinguishes between extensive and intensive margins. We consider calibrated versions of this model that dier in the value of a key preference parameter for labor supply and the extent of heterogeneity. The model is able to capture the salient features of the empirical distribution of hours worked, including how individuals transit within this distribution. We then study how the various specications inuence labor supply responses to aggregate technology shocks. We nd that abstracting from intensive margin adjustment has large eects on the volatility of aggregate hours even if intensive margin uctuates relatively little.

Different approaches to estimation of the characteristic undrained shear strength of soil are discussed, based on 12 cone penetration tests (CPTs) carried out within a soil volume representative of an offshore monopile foundation. The paper is focused on the statistical treatment of the data, and pile‐soil interaction is modelled by the Winkler approach with nonlinear p‐y curves for the soil resistance. The 5MW NREL reference wind turbine is employed for load estimation, utilizing the aeroelastic code FAST. The study includes comparison of monopile capacities based on a single CPT as well as multiple CPTs. Comparisons are made between results obtained from a single CPT and those from all the CPTs at the site. The influence of assuming few or many layers in the deterministic soil model is assessed, and different assumptions regarding the statistical distribution of the data are compared. Finally, based on findings of the analyses, guidelines for the estimation of the characteristic soil strengths are proposed.

Based on a quantitative, heterogeneous agent general equilibrium model, we compute the optimal tax rates for labor and capital incomes for the Korean economy. According to our model, a more progressive income tax schedule along with a higher capital tax rate can increase average welfare by as much as 0.86% of permanent consumption. Approximately 64% of house-holds, those with low assets and low productivity, are better off when a more progressive optimal tax schedule is adopted. Despite the potentially significant welfare gains, our calculation should be interpreted with caution because our benchmark model does not take into account possible capital outflows or the increased administrative costs associated with high taxes.

Extensive discussion on the optimal types of offshore wind turbine(OWT) among monopile, tripod and jacket in the intermediate depth of water has been actively carried out in worldwide wind turbine industry. Selecting the optimal types of OWT among several substructural types, it is required to consider the economic and technical feasibility including dynamically stable design of a wind turbine system. In this study, the effects of loading levels and uncertainties of soil properties on the natural frequency of OWT have been quantitatively investigated. In conclusion, the natural frequency of monopile-type OWTs has a significant level of uncertainty, hence it is very important to minimize the level of uncertainties in soil properties when the monopile is selected as a foundation for an OWT.

This paper is aimed to suggest a site specific partial safety factor of offshore wind turbine (OWT) pile foundation design for the offshore wind turbine complex at a West-South mainland sea in Korea. International offshore wind design standards such as IEC, GL, DNV, API, ISO and EUROCODE were compared with each partial safety factor and resistance factor. Soil uncertainty analysis using a la rge number of soil data sampled was carried out, and their results were adapted to estimate partial safety factor of OWT pile found ation through reliability analyses. The representative partial safety factor has been estimated as 1.3. When a proposed partial facto r is willing to use to other sites, it is recommended that further studies on code calibration are required to validate their accuracy using more site characterization data.Key words : Offshore wind turbine, Pile foundation, Reliability based design, Partial factor, Resistance factor, Soil variability초 록본 논문은 국내 서남해안 해상풍력발전 하부기초설계 시 신뢰성 기반의 한계상태설계법 적용을 위한 말뚝기초의 부분안전계수를 제안하고자 한다. 우선, 해상풍력관련 국제 설계기준서인 IEC, GL, DNV, API, ISO, EUROCODE 등에서 제시한 다양한 부분안전계수 및 저항계수를 비교‧분석하였다. 그리고 부안-영광 및 새만금 해역의 서남해안 해상풍력단지의 지반조사 결과를 가지고 불확실성 분석을 수행하였다 . 불확실성분석 결과를 토대로 신뢰성해석을 수행하여 지반정수에 대한 부분안전계수를 산정하였으며, 서남해안 지역의 해상풍력 말뚝기초의 부분안전계수는 1.3으로 평가되었다. 본 논문에서 제안된 부분안전계수는 서남해안에서의 지반조사 결과를 근거로 산정된 것이므로 기타 광역단위 해역에 활용하기 위해서는 추가적인 조사 및 지반정수에 대한 불확실성 분석을 통해 보정이 필요하다고 판단된다 . 검색어 : 해상풍력, 말뚝기초, 신뢰성 설계, 부분안전계수, 저항계수, 지반 변동성

2014ABSTRACT : This paper presents the results of a numerical investigation on applicability of Light-weighted Foam Soils (LWFS) consisted of dredged soils for soft ground improvement. The engineering properties of LWFS were comprehensively investigated based on the previous experimental tests. And three dimensional numerical models which reflect soft ground conditions were adopted to evaluate the applicability of LWFS compared to SCP and DCM. A number of cases were analyzed using a stress-pore pressure coupled model. The results indicated that LWFS method enables to reduce more settlement, lateral flow and heaving than SCP method and enable to reduce more residual settlement than DCM method. Also it was revealed that such effect depends on the properties of LWFS such as unit weight, unconfined compressive strength, deformation modulus and Poisson’s ratio.Keywords : Light-weight Air Foamed Soils (LWFS), Dredged soils, Soft ground improvement, Finite element analysis요지 : 본 논문에서는 준설토를 활용한 경량혼합토(LWFS)의 연약지반개량 적용성에 대해 검토한 내용을 다루었다. 현재까지 제시된 경량혼합토의 공학적 특성에 관한 연구결과를 종합･분석하여 경량혼합토의 물성을 정리하였으며, 그 결과를 토대로 임의의 현장조건을 가정하여 경량혼합토공법과 SCP 공법 및 DCM 공법 적용 시에 대한 3차원 수치해석을 수행하였다. 연약지반개량공법 비교해석 결과, 경량혼합토 공법을 적용하는 경우 SCP 공법을 적용하는 수준 이상의 침하관리가 가능하며 , 경량혼합토의 목표성능에 따라 침하발생 수준을 조절할 수 있는 것으로 검토되었다 . 또한 DCM 공법과 비교 시 경량혼합토 재료의 경량성으로 과잉간극수압 발생량이 현저히 작아져 잔류침하를 최소화할 수 있는 것으로 검토되었다 .주요어 : 경량혼합토, 준설토, 연약지반개량, 유한요소해석

We demonstrate that aggregate employment and consumption can increase without a corresponding movement in productivity in a model with heterogeneous agents where the only aggregate disturbance is a productivity shock. The interaction between incomplete capital markets and indivisible labor results in a low employment-productivity correlation and creates a time-varying wedge between the marginal rate of substitution (for commodity consumption and hours) and productivity. Our results caution against viewing the measured wedge as an inefficiency due to a failure of labor-market clearing or as a fundamental driving force behind business cycles. (JEL D31, E32, J22, J24, J31)

We develop a multi-country quantitative model of the global distribution of current account and external balances. Countries accumulate domestic capital and foreign assets to smooth consumption over time against exogenous productivity shocks in the presence of liquidity constraints. In equilibrium, optimal consumption and investment responses to persistent productivity shocks imply a degree of intertemporal substitution across countries that can explain up to one-third of the current account dispersion in the data.

Worker heterogeneity in productivity and labor supply is introduced into a matching model. Workers who earn high wages and work high-hours are identified as those with strong market comparative advantage—high rents from being employed. The model is calibrated to match separation, job finding, and employment in the SIPP data. The model predicts a big drop in employment for workers with weak comparative advantage during recessions. But the data show that workers with strong comparative advantage also display sizable employment fluctuations, implying that aggregate employment fluctuations are not explained by the responses of workers with small rents to employment.

We construct a family model of labor supply that features adjustment along both the intensive and extensive margin. Intensive margin adjsutment is restricted to two values: full-time work and part-time work. Using simulated data from the steady state of the calibrated model, we examine whether standard labor supply regressions can uncover the true value of the intertemporal elasticity of labor supply parameter. We find positive estimated elasticities that are larger for women and that are highly significant, but they bear virtually no relationship to the underlying preference parameters.

We model worker heterogeneity in the rents from being employed in a Diamond-Mortensen-Pissarides model of matching and unemployment. We show that heterogeneity, reflecting differences in match quality and worker assets, reduces the extent of fluctuations in separations and unemployment. We find that the model faces a trade-off— it cannot produce both realistic dispersion in wage growth across workers and realistic cyclical fluctuations in unemployment. (JEL D31, E24, E32, J41, J63)

Accounting for observed fluctuations in aggregate employment, consumption, and real wage using the optimality conditions of a representative household often requires preferences that are incompatible with economic priors (e.g., Mankiw, Rotemberg, and Summers 1985). This discrepancy between the equilibrium model and the aggregate data is often viewed as evidence of the failure of labor-market clearing. We argue that such a conclusion is premature. We construct a model economy where all prices are flexible and all markets clear at all times but household decisions are not readily aggregated because of incomplete capital markets and the indivisible nature of the labor supply. We demonstrate that if we were to explain the model-generated aggregate time series using decisions of a fictitious" stand-in household, such a household is likely to have a non-concave or unstable utility. Our analysis suggests that the representative-agent model often fails to represent an equilibrium outcome of a heterogeneous-agent economy.

This paper presents the results of a full-scale load test and a 3D finite element analysis on a two-tier, 5 m high, geosynthetic reinforced segmental retaining wall (GR-SRW) subjected to a surcharge load aiming at investigating the response of the GR-SRW to various levels of surcharge load. The results of the load test at working stress condition revealed that the GR-SRW's response to the test load was well within the serviceability limits, and that the currently available design guideline tends to over-estimate the surcharge load-induced reinforcement forces. The predicted results for the surcharge load well in excess of the test load indicated that the surcharge load-induced reinforcement strains exponentially decrease with depth, showing a good agreement in qualitative terms with that assumed in the FHWA design guideline. The predicted wall deformation at the allowable bearing pressure of 200 kPa was within the serviceability level demonstrating an excellent load carrying capacity of the GR-SRW. Design implications and the findings from this study are discussed.

This paper considers a heterogeneous agent dynamic general equilibrium model and analyzes effects of an increase in labor income tax rate on labor market and the aggregate variables in Korea. The fiscal policy regarding how the government uses the additional tax revenue may take the two forms: 1) general transfer and 2) earned income tax credit (EITC). The model features are as follows: 1) Workers are heterogeneous in their productivity. 2)Labor is indivisible, hence the analysis focuses on the variation in labor supply through the extensive margin in response to a change in fiscal policy. 3) The incomplete markets are introduced, so individual workers can not perfectly insure themselves against risks related to stochastic changes in income or employment status. 4) The model is of general equilibrium, hence it is equiped to analyze the feedback effect of changes in aggregate variables on individual workers' decisions. In the case of general transfer policy, the government equally distributes the additional tax revenue to all workers regardless of their employment states. Under this policy, an increase in the labor income tax rate dampens work incentives of individual workers so that the aggregate employment rate decreases by 1% compared with the benchmark economy. In the case of EITC policy, only employed workers whose labor incomes are below a certain EITC ceiling are eligible for the EITC benefits. Unlike the general transfer policy, the EITC induces low-income workers to participate the labor market to be eligible for EITC benefits. Hence, the aggregate employment rate may increase by 2.7% at the maximum. As the EITC ceiling increases, too many workers can collect the EITC but the benefits per worker becomes too little so that the increase in employment rate is negligible. By and large, this study demonstrates that EITC may effectively raise the aggregate employment rate, and that it can be a useful policy tool in response to the decrease in the labor force due to population aging as observed in Korea recently.

We demonstrate that aggregate employment and consumption can increase without a corresponding movement in productivity in a model with heterogeneous agents where the only aggregate disturbance is a productivity shock. The interaction between incomplete capital markets and indivisible labor results in a low employment-productivity correlation and creates a time-varying wedge between the marginal rate of substitution (for commodity consumption and hours) and productivity. Our results caution against viewing the measured wedge as an inefficiency due to a failure of labor-market clearing or as a fundamental driving force behind business cycles. (JEL D31, E32, J22, J24, J31)

Monopiles are the most widely utilized foundation for offshore wind turbines (OWTs) in shallow waters. However, jacket-type foundations are being considered as one of the good alternatives to monopole foundations for relatively deep water in the range of 25–50 m of water depth. Jacket structures are conventionally used in the oil and gas industry. However, there are still several issues unsolved for utilization of jacket structures for OWTs including pile–soil-interaction (PSI) effects, dynamically stable design, installation, and so on. In this study,the effects of pile–soil interaction on the dynamic properties of jacketsupported OWTs are investigated. The jacket structure is modeled as a four-legged multi-member structure with vertical pre-piles, and the PSI effects on dynamic properties of the structure are evaluated using Monte Carlo simulation considering uncertainties in soil properties.

We develop a quantitative, heterogeneous-agents general equilibrium model that reproduces the income inequalities of 31 countries in the Organization for Economic Co-operation and Development. Using this model, we compute the optimal income tax rate for each country under the equal-weight utilitarian social welfare function. We simulate the voting outcome for the utilitarian optimal tax reform for each country. Finally, we uncover the Pareto weights in the social welfare functions of each country that justify the current redistribution policy.

We consider a matching model of employment with wages that are flexible for new hires, but sticky within matches. We depart from standard treatments of sticky wages by allowing effort to respond to the wage being too high or low. Shimer (2004) and others have illustrated that employment in the Mortensen-Pissarides model does not depend on the degree of wage flexibility in existing matches. But this is not true in our model. If wages of matched workers are stuck too high in a recession, then firms will require more effort, lowering the value of additional labor and reducing new hiring.Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

We consider a matching model of employment with wages that are exible for new hires, but sticky within matches. We depart from standard treatments of sticky wages by allowing worker eort to respond to the wage being too high or low, rendering the eective

This article uses data from the National Longitudinal Study of Youth to examine the phenomenon of later life education among women who first give birth as teenagers. The analysis first considers patterns of educational attainment through the middle 30s for all women, disaggregated by age at first birth. This allows for an examination of the amount of education received by teen mothers relative to women who delay giving birth until adulthood. The analysis also considers racial-ethnic differences in patterns of attainment. Next, the analysis is restricted to teen mothers and focuses on an examination of the composition of educational attainment according to the amount of time that has elapsed since the first birth. The findings suggest that later life education among teen mothers is an important and understudied phenomenon with implications for welfare reform and adult education policies.

Interpolated second-order polynomials (ISOPs) are proposed to design efficient cascaded integrator-comb (CIC)-based decimation filters for a programmable downconverter. It is shown that some simple ISOPs can effectively reduce the passband droop caused by CIC filtering with little degradation in aliasing attenuation. In addition, ISOPs are shown to be useful for simplifying halfband filters that usually follow CIC filtering. As a result, a modified halfband filter (MHBF) is introduced which is simpler than conventional halfband filters. The proposed decimation filter for programmable downconverter is a cascade of a CIC filter, an ISOP, MHBFs, and a programmable finite impulse response filter. A procedure for designing the decimation filter is developed. In particular, an optimization technique that simultaneously designs the ISOP and programmable FIR filters is presented. Design examples demonstrate that the proposed method leads to more efficient programmable downconverters than existing ones.