A novel hybrid algorithm based on a harmony search and artificial bee colony for solving a portfolio optimization problem using a mean-semi variance approach

Portfolio selection is one of the major capital allocation and budgeting issues in financial management, and a variety of models have been presented for optimal selection. Semi-variance is usually considered as a risk factor in drawing up an efficient frontier and the optimal portfolio. Since semi-variance offers a better estimation of the actual risk portfolio, it was used as a measure to approximate the risk of investment in this work. The optimal portfolio selection is one of the non-deterministic polynomial(NP)-hard problems that have not been presented in an exact algorithm, which can solve this problem in a polynomial time. Meta-heuristic algorithms are usually used to solve such problems. A novel hybrid harmony search and artificial bee colony algorithm and its application were introduced in order to draw efficient frontier portfolios. Computational results show that this algorithm is more successful than the harmony search method and genetic algorithm. In addition, it is more accurate in finding optimal solutions at all levels of risk and return.

On the Singular Biharmonic Problems Involving Critical Sobolev Exponents

Abstract： Let Ω belong to R^N be a smooth bounded domain such that 0 ∈ Ω, N ≥ 5, 2^＊ ：2N/N-4 is the critical Sobolev exponent, and f（x） is a given function. By using the variational methods, the paper proves the existence of solutions for the singular critical in the homogeneous problem △^u-μ u/{x}^4=｜μ｜^2＊-2u＋f（x） with Dirichlet boundary condition on 偏dΩ under some assumptions on f（x） and μ.

The Diplomatic Offensive of the DPRK and Challenges Faced

Actively taking the opportunity of participating in the Pyeongchang Winter Olympic Games held last February, the Democratic People's Republic of Korea(DPRK) launched a fierce diplomatic offensive: in March, Kim Jong-un, Chairman of the Korean Workers' Party, paid a visit to China; in April, the DPRK-ROK summit was held;and the DPRK and the US also announced that they would hold a summit in early June. Kim Jong-un has made positive moves, particularly on the nuclear issue: when visiting China, he affirmed that the DPRK would remain committed to denuclearization of the peninsula; at the Third Plenary Session of the 7 th National Congress of the Korean Workers' Party, he announced the termination of nuclear testing and the intercontinental ballistic missile(ICBM) test launches, as well as the abjuration of the nuclear testing site in the north; and later on, he affirmed with Moon Jae-in, President of the Republic of Korea(ROK), that the common goal of a nuclear free peninsula would be realized through denuclearization. This series of diplomatic moves by the DPRK has taken the world by surprise. The DPRK government's motivations are both internal and external. In their attempts to preserve and deepen the hard-won peace, and make it a true turning point in their history, the DPRK is obviously faced with multiple challenges, and a lot of work has to be done on the nuclear issue in particular.

Stress on Ballast-Bed and Deterioration of Geometry in a Railway Track

In Greece extended cracking of twin-block concrete sleepers （ties） and fouling of the ballast-bed were observed with implied problems of gauge widening and deterioration of track＇s geometry. This led to a ten-year investigation program, during which a new method was developed for the estimation of actions on track panel as well as of the pressures / stresses that develop under the seating surface of the sleeper on the ballast-bed. Results from the tests performed on the ballast used in the Greek network are also presented, conducted in laboratories in France, Austria, and Greece. The influence of the actions -static and mainly dynamic- on the track response and the stress and strain of the ballast-bed are also discussed as derived from the tests and theoretical analysis.

Territorial Analysis of Medical-geographycal Conditions and the Problems of Health of the Population of the Republic of Uzbekistan

The Republic of Uzbekistan differs amongst other countries of the Central Asia by its peculiar medical-geographical conditions. Uzbekistan has dry, roast summer and cool winter which is uncharacteristic to subtropical climate. These factors have certain influence on health of the population. The meteorological conditions of each season promote the activations or decrease of various diseases in the Republic. The growth of the diseases of digestive organs, respiratory apparatus and cardiovascular diseases cause the special anxiety in the country. The analysis shows that from 1999 to 2009 nosogeographical situation is mostly worsened in Navaiy region. On the contrary, in the regions of Dzhizak, Samarkand and Khorezm common sickness rate of the population is decreased slightly.

蔡元培与威廉·洪堡教育思想之比较研究

对蔡元培和洪堡两位教育家的教育思想和实践做了一个粗略的比较，比较的重点是他们的教育独立观，他们对完全人格教育的看法以及他们的大学改革实践。

How does the Civil Code Process the Civil and Commercial Relations According to the Insurance Law

The relationship between the civil law and commercial law is a long-standing issue of controversy in the area of private law, and it is also an issue of unavoidably legislative selection during the codification the civil code in almost every country. Since the founding of the People Republic of China, China has carried out the codification of civil code for four times, and since the part^s eighteen plenary session officially proposed the ＇codification of civil code＇, the issue of the civil and conmaercial relation draws the attention again, either unification or division of civil and commercial law directly affects the system and content of the civil code, and affects how to process the relationship between the civil law and commercial law during the codification of the civil code as well. The codification of the civil code should not only consider the legislative tradition of the civil and commercial legislation and the current legal system, but also pursue characteristics of the commercial law, in a system of combining civil and commercial law, through adding commercial law into the general principle of civil law; the existing commercial law should be separately retained.

Early Era Republic Term （1923-1938）： A Look Into the Education of Women in Turkish Novel

In this work, the reflection of the education of women from the social problems in the early republic era when the novel genre was developed will be examined. In the study, in specific early republic era which covers the years 1923-1938, the theme of the education of women in Turkish novel, in general, the reflections of the look into the education of women by the Republic Era Turkey on literature of the era have been studied. The attitude in the novels which criticizes the educational institutes through the educational issues also shows similarities with the look of republic ideology into education. While the mentioned educational institutes of early republic are being systemized, the negative sides of existing educational institutes have been examined. The problems such as the duality in education, the education of the girls, modern, and neighborhood school＇s education together have been studied as subheadings. The goal of the study is to determine the insufficiency of the educational institutes which has become a social problem in Turkish novel with respect to the term novels. Within this respect, while the introduction part describes the conditions of the era on education, the part which constitutes the basic of the work, the education problem in the novels dealing with the education of women has been expressed with novel heroes.

Initial Boundary Value Problems for a Class of Non-linear Pseudo-parabolic Equation

In this paper,the existence,the uniqueness,the asymptotic behavior and the non-existence of the global generalized solutions of the initial boundary value problems for the non-linear pseudo-parabolic equation ut-αuxx-βuxxt=F（u）-βF （u）xx are proved,where α,β 0 are constants,F（s） is a given function.

基于UKF的雷达和机载ESM扩维跟踪

为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标的定位跟踪,以求进一步减小扩维后线性化误差加大等问题的影响。仿真结果表明,该算法可更好地实现对目标的定位跟踪。

Response-surface-based structural reliability analysis with random and interval mixed uncertainties

Traditional reliability analysis requires probability distributions of all the uncertain parameters.However,in many practical applications,the variation bounds can be only determined for the parameters with limited information.A complex hybrid reliability problem then will be caused when the random and interval variables coexist in a same structure.In this paper,by introducing the response surface technique,we develop a new hybrid reliability method to efficiently compute the interval of the failure probability of the structure due to the probability-interval hybrid uncertainty.The present method consists of a sequence of iterations.At each step,a response surface model is constructed for the limit-state function by using a quadratic polynomial and a modified axial experimental design method.An approximate hybrid reliability problem is created based on the response surface model,which is subsequently solved by an efficient decoupling approach.An updating strategy is suggested to improve the quality of the response surface and whereby ensure the reliability analysis precision.A computational procedure is then summarized for the whole iterations.Four numerical examples and also a practical application are provided to demonstrate the effectiveness of the present method.

1-Bit compressive sensing: Reformulation and RRSP-based sign recovery theory

Recently, the 1-bit compressive sensing （1-bit CS） has been studied in the field of sparse signal recovery. Since the amplitude information of sparse signals in 1-bit CS is not available, it is often the support or the sign of a signal that can be exactly recovered with a decoding method. We first show that a necessary assumption （that has been overlooked in the literature） should be made for some existing theories and discussions for 1-bit CS. Without such an assumption, the found solution by some existing decoding algorithms might be inconsistent with 1-bit measurements. This motivates us to pursue a new direction to develop uniform and nonuniform recovery theories for 1-bit CS with a new decoding method which always generates a solution consistent with 1-bit measurements. We focus on an extreme case of 1-bit CS, in which the measurements capture only the sign of the product of a sensing matrix and a signal. We show that the 1-bit CS model can be reformulated equivalently as an t0-minimization problem with linear constraints. This reformulation naturally leads to a new linear-program-based decoding method, referred to as the 1-bit basis pursuit, which is remarkably different from existing formulations. It turns out that the uniqueness condition for the solution of the 1-bit basis pursuit yields the so-called restricted range space property （RRSP） of the transposed sensing matrix. This concept provides a basis to develop sign recovery conditions for sparse signals through 1-bit measurements. We prove that if the sign of a sparse signal can be exactly recovered from 1-bit measurements with 1-bit basis pursuit, then the sensing matrix must admit a certain RRSP, and that if the sensing matrix admits a slightly enhanced RRSP, then the sign of a k-sparse signal can be exactly recovered with 1-bit basis pursuit.

On Reed-Solomon Codes

The complexity of decoding the standard Reed-Solomon code is a well-known open problem in coding theory.The main problem is to compute the error distance of a received word.Using the Weil bound for character sum estimate,Li and Wan showed that the error distance can be determined when the degree of the received word as a polynomial is small.In the first part,the result of Li and Wan is improved.On the other hand,one of the important parameters of an error-correcting code is the dimension.In most cases,one can only get bounds for the dimension.In the second part,a formula for the dimension of the generalized trace Reed-Solomon codes in some cases is obtained.

A Finite Genus Solution of the Veselov's Discrete Neumann System

The Veselov's discrete Neumann system is derived through nonlinearization of a discrete spectral problem.Based on the commutative relation between the Lax matrix and the Darboux matrix with finite genus potentials,a special solution is calculated with the help of the Baker-Akhiezer-Kriechever function.

On the Dedekind Sums and Two-Term Exponential Sums

In this paper, the authors use the analytic methods and the properties of character sums mod p to study the computational problem of one kind of mean value involving the classical Dedekind sums and two-term exponential sums, and give an exact computational formuiu for it.

Infinitely many solutions to elliptic systems with critical exponents and Hardy potentials

In this paper,a system of elliptic equations is investigated,which involves Hardy potential and multiple critical Sobolev exponents.By a global compactness argument of variational method and a fine analysis on the Palais-Smale sequences created from related approximation problems,the existence of infinitely many solutions to the system is established.

INITIAL-BOUNDARY VALUE PROBLEM FOR THE UNSATURATED LANDAU-LIFSHITZ SYSTEM

The existence, partial regularity and uniqueness of weak solution to the initial boundary value problem for the unsaturated Landau-Lifschitz systems are given.

A PENALTY FUNCTION METHOD FOR SOLVING ILL-POSED BILEVEL PROGRAMMING PROBLEM VIA WEIGHTED SUMMATION

For ill-posed bilevel programming problem,the optimistic solution is always the best decision for the upper level but it is not always the best choice for both levels if the authors consider the model's satisfactory degree in application.To acquire a more satisfying solution than the optimistic one to realize the two levels' most profits,this paper considers both levels' satisfactory degree and constructs a minimization problem of the two objective functions by weighted summation.Then,using the duality gap of the lower level as the penalty function,the authors transfer these two levels problem to a single one and propose a corresponding algorithm.Finally,the authors give an example to show a more satisfying solution than the optimistic solution can be achieved by this algorithm.

The Uniqueness of Inverse Problem for the Dirac Operators with Partial Information

The inverse spectral problem for the Dirac operators defined on the interval[0, π] with self-adjoint separated boundary conditions is considered. Some uniqueness results are obtained, which imply that the pair of potentials(p(x), r(x)) and a boundary condition are uniquely determined even if only partial information is given on(p(x), r(x))together with partial information on the spectral data, consisting of either one full spectrum and a subset of norming constants, or a subset of pairs of eigenvalues and the corresponding norming constants. Moreover, the authors are also concerned with the situation where both p(x) and r(x) are C n-smoothness at some given point.