Default Prediction for Real Estate Companies with Imbalanced Dataset

Dong, Yuan-Xiang,Xiao, Zhi,Xiao, Xue Korea Information Processing Society 2014 Journal of information processing systems Vol.10 No.2

When analyzing default predictions in real estate companies, the number of non-defaulted cases always greatly exceeds the defaulted ones, which creates the two-class imbalance problem. This lowers the ability of prediction models to distinguish the default sample. In order to avoid this sample selection bias and to improve the prediction model, this paper applies a minority sample generation approach to create new minority samples. The logistic regression, support vector machine (SVM) classification, and neural network (NN) classification use an imbalanced dataset. They were used as benchmarks with a single prediction model that used a balanced dataset corrected by the minority samples generation approach. Instead of using prediction-oriented tests and the overall accuracy, the true positive rate (TPR), the true negative rate (TNR), G-mean, and F-score are used to measure the performance of default prediction models for imbalanced dataset. In this paper, we describe an empirical experiment that used a sampling of 14 default and 315 non-default listed real estate companies in China and report that most results using single prediction models with a balanced dataset generated better results than an imbalanced dataset.

Molecular Cloning, Tissue Distribution and Segmental Ontogenetic Regulation of b^0,+ Amino Acid Transporter in Lantang Pigs

Zhi, Ai-Min,Feng, Ding-Yuan,Zhou, Xiang-Yan,Zou, Shi-Geng,Huang, Zhi-Yi,Zuo, Jian-Jun,Ye, Hui,Zhang, Chang-Ming,Dong, Ze-Min,Liu, Zhun Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.8

Cationic amino acid transporter $b^{0,+}AT$ (HGMW-approved gene symbol SLC7A9, solute carrier family 7, member 9) plays a crucial role in amino acid nutrition. In the present study, we describe the cloning and sequencing of porcine $b^{0,+}AT$. Based on the sequence of porcine $b^{0,+}AT$ deposited in the NCBI (National Center for Biotechnological Information), we identified a putative porcine homologue. Using rapid amplification of cDNA ends (RACE), the full-length cDNA encoding porcine $b^{0,+}AT$ was isolated. The porcine $b^{0,+}AT$ cDNA was 1,680 bp long, encoding a 487 amino acid trans-membrane protein. The predicted amino acid sequence was found to have 88.9% and 87.1% identity with human and mouse $b^{0,+}AT$, respectively. Real-time RT-PCR indicated porcine $b^{0,+}AT$ transcripts expressed in heart, kidney, muscle and small intestine. The small intestine had the highest $b^{0,+}AT$ mRNA abundance while the muscle had the lowest (p<0.05). Along the longitudinal axis, the ileum had the highest $b^{0,+}AT$ mRNA abundance while the colon had the lowest (p<0.05). The $b^{0,+}AT$ mRNA level was highest on day 7 and 90 in the duodenum (p<0.05). It increased from day 1 to day 26 in the jejunum (p>0.05) and had the highest abundance on day 60 (p<0.05). There was, however, no difference between day 1, 7, 26, 30, 90 and 150 (p>0.05). The strongest $b^{0,+}AT$ expression appeared on day 7 in the ileum before weaning, and then decreased till day 30 but rose gradually again from day 60 to 150 (p<0.05).

The research for Chinese CDM risk and its countermeasures

Yuan-ying Chi,Dong-xiao Niu,Zhi Lie,Xiang-yang Li 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

With the global climate becoming worse and warmer, the Kyoto Protocol"s signing leads to the birth of CDM, which is one of the three mechanism in the protocol and aims to realize the greenhouse air reduction via the projects cooperation between the developed country and developing country. Although so many successful CDM projects have been finished so far and plentiful experiences have also been accumulated by us, we still encounter many risks during the course of CDM projects implementing which can also bring great potential losses to economy. This article aims to analyze the possible CDM risks from three categories including traditional aspect, process aspect, and market aspect and presents the possible measures to mitigate the risks in order to make us keep sober-minded at the risks.

An Improved Variable Step Size MPPT Algorithm Based on INC

Zhi-rong Xu,Ping Yang,Dong-bao Zhou,Peng Li,Jin-yong Lei,Yuan-rui Chen 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2

In order to ensure that photovoltaic (PV) systems work at the maximum power point (MPP) and maximize the economic benefits, maximum power point tracking (MPPT) techniques are normally applied to these systems. One of the most widely applied MPPT methods is the incremental conductance (INC) method. However, the choice of the step size still remains controversial. This paper presents an improved variable step size INC MPPT algorithm that uses four different step sizes. This method has the advantages of INC but with the ability to validly adjust the step size to adapt to changes of the PV’s power curve. The presented algorithm also simultaneously achieves increased rapidity and accuracy when compared with the conventional fixed step size INC MPPT algorithm. In addition, the theoretical derivation and specific applications of the proposed algorithm are presented here. This method is validated by simulation and experimental results.

The grey relational degree anallysis of the Jilin modern logistics and the modern service industry

Yuan-ying Chi,Yuan-qian chi,Dong-xio Niu,Zhi Liu 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

The development level of modern service industry is an important symbol for country or region’s comprehensive competitiveness, the modern service industry of jilin provence, which is key supported by the logistics, ha played a great role in the national economomy and it’s effect has become more and more prominent. Based on the grey relational analysis method, the paper analyzes the logistics and the whole modern service industry (tertiary industry) of jilin province which also analyzes the corelation degree among the tertiary industry and the primary and secondary industries the paper aims to find the existing problems in the modern industry and put and forward the corresponding countermeasures promoting the development of Jilin morden service industry.

Default Prediction for Real Estate Companies with Imbalanced Dataset

( Xiang Dong Yuan ),( Zhi Xiao ),( Xue Xiao ) 한국정보처리학회 2014 Journal of information processing systems Vol.10 No.2

When analyzing default predictions in real estate companies, the number of non-defaulted cases always greatly exceeds the defaulted ones, which creates the twoclass imbalance problem. This lowers the ability of prediction models to distinguish the default sample. In order to avoid this sample selection bias and to improve the prediction model, this paper applies a minority sample generation approach to create new minority samples. The logistic regression, support vector machine (SVM) classification, and neural network (NN) classification use an imbalanced dataset. They were used as benchmarks with a single prediction model that used a balanced dataset corrected by the minority samples generation approach. Instead of using prediction oriented tests and the overall accuracy, the true positive rate (TPR), the true negative rate (TNR), G-mean, and F-score are used to measure the performance of default prediction models for imbalanced dataset. In this paper, we describe an empirical experiment that used a sampling of 14 default and 315 non-default listed real estate companies in China and report that most results using single prediction models with a balanced dataset generated better results than an imbalanced dataset.

An Improved Variable Step Size MPPT Algorithm Based on INC

Xu, Zhi-Rong,Yang, Ping,Zhou, Dong-Bao,Li, Peng,Lei, Jin-Yong,Chen, Yuan-Rui The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2

In order to ensure that photovoltaic (PV) systems work at the maximum power point (MPP) and maximize the economic benefits, maximum power point tracking (MPPT) techniques are normally applied to these systems. One of the most widely applied MPPT methods is the incremental conductance (INC) method. However, the choice of the step size still remains controversial. This paper presents an improved variable step size INC MPPT algorithm that uses four different step sizes. This method has the advantages of INC but with the ability to validly adjust the step size to adapt to changes of the PV's power curve. The presented algorithm also simultaneously achieves increased rapidity and accuracy when compared with the conventional fixed step size INC MPPT algorithm. In addition, the theoretical derivation and specific applications of the proposed algorithm are presented here. This method is validated by simulation and experimental results.

Experimental Research and Numerical Simulation of a Large-span Isolated Structure Considering Multi-dimensional Input Effects

Zhen-yuan Gu,Shu-guang Wang,Weiqing Liu,Dong-sheng Du,Wei-zhi Xu 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.4

Based on the shaking table test of 1:20 scale structural models of the large-span isolated and non-isolated flat grid structures under the action of horizontal-bidirectional (2D) and three-dimensional (3D) rare earthquake, the dynamic characteristics, including natural vibration frequency, damping ratio, the acceleration and displacement responses are investigated. The results show that the base isolation could significantly prolong the structural vibration periods and increase the damping ratio. The capacity of energy dissipation for the base-isolated structure can also be improved. The horizontal acceleration amplification factors (AAFs) of the structure can be reduced greatly due to the base isolation, which effectively reduces the vertical vibration of the large-span grid. Under the 3D seismic input, the horizontal AAF of each layer is greater than that under the 2D one, which illustrates that the vertical seismic input increases the horizontal dynamic response of the structure. Furthermore, the finite element models of the isolated and non-isolated structures were simulated. The experimental results are in good agreement with the numerical results. The parameter optimization of isolation bearings was conducted by using finite element software. The seismic response of each layer under different shear to weight ratios (μ) was analyzed. It can be found that the parameters of the isolation layer have an optimal range which makes the dynamic response of the structure reach a minimum value under the rare earthquake.

Reinforcement layout design for deep beam based on BESO of multi-level reinforcement diameter under discrete model

Hu-zhi Zhang,Peng Luo,Jian Yuan,Yao-sen Huang,Jia-dong Liu 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.84 No.4

By presetting various reinforcement diameters in topology optimization with the discrete model finite element analysis, an algorithm of bidirectional evolutionary structural optimization of multi-level reinforcement diameter is presented to obtain the optimal reinforcement topologies which describe the degree of stress of different parts. The results of a comparative study on different reinforcement feasible domain demonstrate that the more angle types of reinforcement are arranged in the initial domain, the higher utilization rate of reinforcement of the optimal topology becomes. According to the nonlinear finite element analysis of some deep beam examples, the ones designed with the optimization results have a certain advantage in ultimate bearing capacity, although their failure modes are greatly affected by the reinforcement feasible domain. Furthermore, the bearing capacity can be improved when constructional reinforcements are added in the subsequent design. However the adding would change the relative magnitude of the bearing capacity between the normal and inclined section, or the relative magnitude between the flexural and shear capacity within the inclined section, which affects the failure modes of components. Meanwhile, the adding would reduce the deformation capacity of the components as well. It is suggested that the inclined reinforcement and the constructional reinforcement should be added properly to ensure a desired ductile failure mode for components.

하수관내 황화수소발생 억제방안 및 하수처리공정의 이로 인한 영향

박동희 ( Dong Hee Park ),( Oriol Guierrez ),( Zhi Guo Yuan ) 한국물환경학회 2010 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2010 No.-