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  • 1.
    Al Musawi, Ahmed
    et al.
    Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för biomedicinsk vetenskap (BMV).
    Hellström, Lina
    Department of Medicine and Optometry, eHealth Institute, Linnaeus University, Kalmar; Pharmaceutical Department, Region Kalmar County, Kalmar.
    Axelsson, Malin
    Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för vårdvetenskap (VV).
    Midlöv, Patrik
    Department of Clinical Sciences Malmö, Center for Primary Health Care Research, Lund University.
    Rämgård, Margareta
    Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för vårdvetenskap (VV).
    Cheng, Yuanji
    Malmö universitet, Fakulteten för teknik och samhälle (TS), Institutionen för materialvetenskap och tillämpad matematik (MTM).
    Eriksson, Tommy
    Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för biomedicinsk vetenskap (BMV). Malmö universitet, Biofilms Research Center for Biointerfaces.
    Intervention for a correct medication list and medication use in older adults: a non-randomised feasibility study among inpatients and residents during care transitions2024Ingår i: International Journal of Clinical Pharmacy, ISSN 2210-7703, E-ISSN 2210-7711, Vol. 46, nr 3, s. 639-647Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background Medication discrepancies in care transitions and medication non-adherence are problematic. Few interventions consider the entire process, from the hospital to the patient’s medication use at home.

    Aim In preparation for randomised controlled trials (RCTs), this study aimed (1) to investigate the feasibility of recruitment and retention of patients and data collection to reduce medication discrepancies at discharge and improve medication adherence and (2) to explore the outcomes of the interventions.

    Method Participants were recruited from a hospital and a residential area. Hospital patients participated in a pharmacist-led intervention to establish a correct medication list upon discharge and a follow-up interview two weeks post-discharge. All participants received a person-centred adherence intervention for three to six months. Discrepancies in the medication lists, the Beliefs about Medicines Questionnaire (BMQ-S), and the Medication Adherence Report Scale (MARS-5) were assessed.

    Results Of 87 asked to participate, 35 were included, and 12 completed the study. Identifying discrepancies, discussing discrepancies with physicians, and performing follow-up interviews were possible. Conducting the adherence intervention was also possible using individual health plans for medication use. Among the seven hospital patients, 24 discrepancies were found. Discharging physicians agreed that all discrepancies were errors, but only ten were corrected in the discharge information. Ten participants decreased their total BMQ-S concern scores, and seven increased their total MARS-5 scores.

    Conclusion Based on this study, conducting the two RCTs separately may increase the inclusion rate. Data collection was feasible. Both interventions were feasible in many aspects but need to be optimised in upcoming RCTs.

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  • 2.
    Baravdish, George
    et al.
    Linköping Univ, Linköping, Sweden.
    Cheng, Yuanji
    Malmö universitet, Fakulteten för teknik och samhälle (TS), Institutionen för materialvetenskap och tillämpad matematik (MTM).
    Svensson, Olof
    Linköping Univ, Linköping, Sweden.
    On a new singular and degenerate extension of the p-Laplace operator2024Ingår i: Nonlinear Analysis, ISSN 0362-546X, E-ISSN 1873-5215, Vol. 244, artikel-id 113553Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study a novel degenerate and singular elliptic operator (Delta) over tilde ((tau, chi)) defined by (Delta) over tilde ((tau, chi))u = tau(x, Du)(|Du|Delta(1)u + chi(x, Du)Delta(infinity)u), where the singular weights tau(x, s) > 0 and chi(x, s) >= 0 are continuous functions on Omega x R-n\{0}. The operator (Delta) over tilde ((tau, chi)) is an extension of Delta((p, q))u |Du|(q)Delta(1)u + (p -1)|Du|(p-2)Delta(infinity)u, p >= 1, q >= 0, introduced by the authors in Baravdishet al. (2020), which in turn is an extension of the p- Laplace operator Delta(p). We establish the well-posedness of the Neumann boundary value problem for the parabolic equation u(t) = (Delta) over tilde ((tau, chi)) in the framework of viscosity solutions. For the solution u, the weight chi controls the evolution along the tangential and the normal directions, respectively, on the level surface of u. The weight tau controls the total speed of the evolution of u. We also prove the consistency and the convergence of the numerical scheme for the finite differences method of the parabolic equation above. Numerical simulations show that our novel nonlinear operator (Delta) over tilde ((tau, chi)) gives better results than both the Perona-Malik (Perona and Malik, 1990) and total variation (TV) methods (Chan and Shen, 2005) when applied to image enhancement.

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  • 3.
    Jakubauskas, Dainius
    et al.
    Malmö universitet, Biofilms Research Center for Biointerfaces. Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för biomedicinsk vetenskap (BMV).
    Jansen, Martin
    Institute of Clinical Chemistry and Laboratory Medicine, Medical Centre, University of Freiburg, Freiburg im Breisgau, Germany.
    Lyngsø, Jeppe
    Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark.
    Cheng, Yuanji
    Malmö universitet, Fakulteten för teknik och samhälle (TS), Institutionen för materialvetenskap och tillämpad matematik (MTM).
    Skov Pedersen, Jan
    Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark.
    Cárdenas, Marité
    Malmö universitet, Fakulteten för hälsa och samhälle (HS), Institutionen för biomedicinsk vetenskap (BMV). Malmö universitet, Biofilms Research Center for Biointerfaces.
    Toward reliable low-density lipoprotein ultrastructure prediction in clinical conditions: A small-angle X-ray scattering study on individuals with normal and high triglyceride serum levels2021Ingår i: Nanomedicine: Nanotechnology, Biology and Medicine, ISSN 1549-9634, E-ISSN 1549-9642, Vol. 31, s. 1-13, artikel-id 102318Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Atherosclerosis is the main killer in the west and therefore a major health challenge today. Total serum cholesterol and lipoprotein concentrations, used as clinical markers, fail to predict the majority of cases, especially between the risk scale extremes, due to the high complexity in lipoprotein structure and composition. In particular, low-density lipoprotein (LDL) plays a key role in atherosclerosis development, with LDL size being a parameter considered for determining the risk for cardiovascular diseases. Determining LDL size and structural parameters is challenging to address experimentally under physiological-like conditions. This article describes the biochemistry and ultrastructure of normolipidemic and hypertriglyceridemic LDL fractions and subfractions using small-angle X-ray scattering. Our results conclude that LDL particles of hypertriglyceridemic compared to healthy individuals 1) have lower LDL core melting temperature, 2) have lower cholesteryl ester ordering in their core, 3) are smaller, rounder and more spherical below melting temperature, and 4) their protein-containing shell is thinner above melting temperature.

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  • 4.
    Lindström, Torsten
    et al.
    Department of Mathematics, Linnæus University, Växjö, S-35195, Sweden.
    Cheng, Yuanji
    Malmö universitet, Fakulteten för teknik och samhälle (TS), Institutionen för materialvetenskap och tillämpad matematik (MTM).
    Chakraborty, Subhendu
    Centre for Ocean Life, Technical University of Denmark, Kemitorvet, Kgs. Lyngby, DK-2800, Denmark; Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsinger, DK-3000, Denmark.
    Destabilization, Stabilization, and Multiple Attractors in Saturated Mixotrophic Environments2020Ingår i: SIAM Journal on Applied Mathematics, ISSN 0036-1399, E-ISSN 1095-712X, Vol. 80, nr 6, s. 2338-2364, artikel-id 19M1294186Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ability of mixotrophs to combine phototrophy and phagotrophy is now well recognized and found to have important implications for ecosystem dynamics. In this paper, we examine the dynamical consequences of the invasion of mixotrophs in a system that is a limiting case of the chemostat. The model is a hybrid of a competition model describing the competition between autotroph and mixotroph populations for a limiting resource, and a predator--prey-type model describing the interaction between autotroph and herbivore populations. Our results show that mixotrophs are able to invade in both autotrophic environments and environments described by interactions between autotrophs and herbivores. The interaction between autotrophs and herbivores might be in equilibrium or cycle. We find that invading mixotrophs have the ability to both stabilize and destabilize autotroph-herbivore dynamics depending on the competitive ability of mixotrophs. The invasion of mixotrophs can also result in multiple attractors.

  • 5.
    Baravdish, George
    et al.
    Linkoping Univ, Linkoping, Sweden..
    Cheng, Yuanji
    Malmö universitet, Fakulteten för teknik och samhälle (TS), Institutionen för materialvetenskap och tillämpad matematik (MTM).
    Svensson, Olof
    Linkoping Univ, Linkoping, Sweden..
    Åström, Freddie
    Heidelberg Univ, Heidelberg, Germany..
    Generalizations of p-Laplace operator for image enhancement: Part 22020Ingår i: Communications on Pure and Applied Analysis, ISSN 1534-0392, E-ISSN 1553-5258, Vol. 19, nr 7, s. 3477-3500Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have in a previous study introduced a novel elliptic operator Delta((p,q))u = vertical bar del u vertical bar(q) Delta(1)u + (p - 1) vertical bar del u vertical bar(p-2)Delta(infinity) u, p >= 1, q >= 0, as a generalization of the p-Laplace operator. In this paper, we establish the well-posedness of the parabolic equation u(t) =vertical bar del u vertical bar(1-q) Delta((1+q,q)), where q = q(vertical bar del u vertical bar) is continuous and has range in [0, 1], in the framework of viscosity solutions. We prove the consistency and convergence of the numerical scheme of finite differences of this parabolic equation. Numerical simulations shows the advantage of this operator applied to image enhancement.

  • 6.
    Lindström, Torsten
    et al.
    Department of Mathematics, Linnaeus University, 35195 Växjö, Sweden.
    Cheng, Yuanji
    Malmö högskola, Fakulteten för teknik och samhälle (TS).
    A Rosenzweig-MacArthur (1963) Criterion for the Chemostat2016Ingår i: Scientific World Journal, E-ISSN 1537-744X, Vol. 2016, artikel-id 5626980Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Kriterium av Rosenzweig-MacArthur (1963) är ett grafiskt kriterium för att belysa lokal stabilitet för Gause-typ Jägar-byte system. Det är oklart om en liknade kriterium också finns för system med resurs term, t ex, chemostat modell (Kooi et al 1998). I denna artikel gav vi ett positivt svar till denna fråga med hjälp av implicit funktion teori.

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  • 7.
    Baravdish, George
    et al.
    Linköping University, Linköping, Sweden.
    Cheng, Yuanji
    Malmö högskola, Fakulteten för teknik och samhälle (TS).
    Svensson, Olof
    Linköping University, Linköping, Sweden.
    Åström, Freddie
    Heidelberg Collaboratory for Image Processing, Heidelberg University, Heidelberg, Germany.
    Extension of p-Laplace operator for image denoising2016Ingår i: System Modeling and Optimization, Springer, 2016, s. 107-116Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this work we introduce a novel operator ∆_(p;q) as an extended family of operators that generalize the p-Laplace operator. The operator is derived with an emphasis on image processing applications, and particularly, with a focus on image denoising applications. We propose a non-linear transition function, coupling p and q, which yields a non-linear ltering scheme analogous to adaptive spatially dependent total variation and linear ltering. Well-posedness of the nal parabolic PDE is established via pertubation theory and connection to classical results in functional analysis. Numerical results demonstrates the applicability of the novel operator∆_ (p;q).

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  • 8. Mastroberardino, Antonio
    et al.
    Cheng, Yuanji
    Malmö högskola, Fakulteten för teknik och samhälle (TS).
    Abdelrazec, Ahmed
    Liu, Hao
    Mathematical modeling of the HIV/AIDS epidemic in Cuba2015Ingår i: International Journal of Biomathematics, ISSN 1793-5245, E-ISSN 1793-7159, Vol. 8, nr 4, s. 1-10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, a nonlinear mathematical model is presented for the transmission dynamics of HIV/AIDS in Cuba. Due to Cuba's highly successful national prevention program, we assume that the only mode of transmission is through contact with those yet to be diagnosed with HIV. We find the equilibria of the governing nonlinear system, perform a linear stability analysis, and then provide results on global stability.

  • 9.
    Lindström, Torsten
    et al.
    Linnaeus University.
    Cheng, Yuanji
    Malmö högskola, Fakulteten för teknik och samhälle (TS).
    Uniqueness of limit cycles for a limiting case of the chemostat: does it justify the use of logistic growth rates?2015Ingår i: Electronic Journal of Qualitative Theory of Differential Equations , E-ISSN 1417-3875, nr 47, s. 1-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On infinitesimally short time intervals various processes contributing to population change tend to operate independently so that we can simply add their contributions (Metz and Diekmann, The dynamics of physiologically structured populations, 1986, p. 3). This is one of the cornerstones for differential equations modeling in general. Complicated models for processes interacting in a complex manner may be built up, and not only in population dynamics. The principle holds as long as the various contributions are taken into account exactly. In this paper we discuss commonly used approximations that may lead to non-removable dependency terms potentially affecting the long run qualitative behavior of the involved equations. We prove that these terms do not produce such effects in the simplest and most interesting biological case, but the general case is left open. Our main result is a rather complete analysis of an important limiting case. Once complete knowledge of the qualitative properties of simple models is obtained, it greatly facilitates further studies of more complex models. A consequence of our analysis is that standard methods can be applied. However, the application of those methods is far from straightforward and require non-trivial estimates in order to make them valid for all values of the parameters. We focus on making these proofs as elementary as possible.

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  • 10. Hansson, Mattias
    et al.
    Brandt, Sami
    Lindström, Johan
    Gudmundsson, Petri
    Malmö högskola, Fakulteten för hälsa och samhälle (HS), Institutionen för biomedicinsk vetenskap (BMV).
    Jujic, Amra
    Malmgren, Andreas
    Cheng, Yuanji
    Malmö högskola, Fakulteten för teknik och samhälle (TS).
    Segmentation of B-mode cardiac ultrasound data by Bayesian Probability Maps2014Ingår i: Medical Image Analysis, ISSN 1361-8415, E-ISSN 1361-8423, Vol. 18, nr 7, s. 1184-1199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we present a model for describing the position distribution of the endocardium in the two-chamber apical long-axis view of the heart in clinical B-mode ultrasound cycles. We propose a novel Bayesian formulation, including priors for spatial and temporal smoothness, and preferred shapes and position. The shape model takes into account both endocardium, atrial region and apex. The likelihood is built using a statistical signal model, which attempts to closely model a censored signal. In addition, the use of a censored Gamma mixture model with unknown censoring point, to handle artefacts resulting from left-censoring of the in US clinical B-mode, is to our knowledge novel. The posterior density is sampled by the Gibbs method to estimate the expected latent variable representation of the endocardium, which we call the Bayesian Probability Map; the map describes the probability of pixels being classified as being within the endocardium. The regularization parameters of the model are estimated by cross-validation, and the results are compared against the two-chamber apical model of Chen et al.

  • 11.
    Yang, Xiuxiang
    et al.
    Department of Mathematics, Weinan Normal University, Weinan 714000 Shaanxi, China.
    Li, Feng
    Department of Mathematics, Weinan Normal University, Weinan 714000 Shaanxi, China.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Global Stability Analysis on the Dynamics of an SIQ Model with Nonlinear Incidence Rate2012Ingår i: Advances in Future Computer and Control Systems;2, Springer, 2012, s. 561-566Konferensbidrag (Refereegranskat)
    Abstract [en]

    An SIQ epidemic model with isolation and nonlinear incidence rate is studied. We have obtained a threshold value R and shown that there is only a disease free equilibrium point when R < 1, and there is also an endemic equilibrium point if R > 1. With the help of Liapunov function, we have shown that disease free- and endemic equilibrium point is globally stable.

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  • 12.
    Cheng, Yuanji
    et al.
    Malmö högskola, Teknik och samhälle (TS).
    Wang, Jin
    Yang, Xiuxiang
    On the global stability of a generalized cholera epidemiological model2012Ingår i: Journal of Biological Dynamics, ISSN 1751-3758, E-ISSN 1751-3766, Vol. 6, nr 2, s. 1088-1104Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we conduct a careful global stability analysis for a generalized cholera epidemiological model originally proposed in [J. Wang and S. Liao, A generalized cholera model and epidemic/endemic analysis, J. Biol. Dyn. 6 (2012), pp. 568–589]. Cholera is a water- and food-borne infectious disease whose dynamics are complicated by the multiple interactions between the human host, the pathogen, and the environment. Using the geometric approach, we rigorously prove the endemic global stability for the cholera model in three-dimensional (when the pathogen component is a scalar) and four-dimensional (when the pathogen component is a vector) systems. This work unifies the study of global dynamics for several existing deterministic cholera models. The analytical predictions are verified by numerical simulation results.

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  • 13.
    Cheng, Yuanji
    et al.
    Malmö högskola, Teknik och samhälle (TS).
    Yang, Xiuxiang
    On the global stability of seirs models in epidemiology2012Ingår i: The Canadian applied mathematics quarterly, ISSN 1073-1849, E-ISSN 1938-2634, Vol. 20, nr 2, s. 115-133Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The global stability of SEIRS models with nonlinear incidence rates was conjectured in [W. M. Liu, H. W. Hethcote and S. A. Levin, J. Math. Biol. 25 (1987), 359-380.] and has been stated as an outstanding open question for classical bilinear models in [M. Y. Li, J. S. Muldowney and P. van den Driessche, Canad. Appl. Math. Q. 7 (1999), 409-425.]. By applying the Poincar e-Bendixson property of dynamic systems in space, the authors in [M. Y. Li and J. S. Muldowney, SIAM J. Math. Anal. 27 (1996), 1070-1083.] have proven the conjecture for the bilinear model with a su fficiently long average immunity period, and in [M. Y. Li, J. S. Muldowney and P. van den Driessche, Canad. Appl. Math. Q. 7 (1999), 409-425.] the authors have shown the case with a suffi ciently long average infection period. In this paper, we solve the open problem for the bilinear case completely, and furthermore have relaxed the constraint on the general nonlinear transmission function for global stability.

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  • 14.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    A generalized Fucik type eigenvalue problem for p-Laplacian2009Ingår i: Electronic Journal of Qualitative Theory of Differential Equations , E-ISSN 1417-3875, nr 18, s. 1-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we study the generalized Fucik type eigenvalue for the boundary value problem of one dimensional $p-$Laplace type differential equations -(φ(u'))' = ψ(u), u(-T) = u(T) =0, where φ(s) = α s^p, ψ(s)= λs^p, s >0; φ(s) = -β|s|^p, ψ(s)= -μ|s|^p, s <0. We say (α, β, λ, μ) belong to the Fucik spectrum, if the above boundary value problem has a non-trival solution. We have obtained a complete and explicit characterization of Fucik spectrum for such problem.

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  • 15.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Exact multiplicity of solutions for p-Laplace type differential equations2009Ingår i: International journal of pure and applied mathematics, ISSN 1311-8080, E-ISSN 1314-3395, Vol. 53, nr 3, s. 395-412Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multiplicity of solutions to the following boundary value problem -(φ(u'))' = λψ(u), T < x < T; u(-T) = u(T) = 0, is considered. There are many works devoted to odd function φ, ψ, but are very few on non-odd cases. For the prototype function φ(u) = au^p, u >0, = -b |u|^q,u < 0 several exact multiplicity results have been established.

  • 16.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Bifurcation of positive solutions for a semilinear equation with critical Sobolev exponent2006Ingår i: Electronic Journal of Differential Equations, ISSN 1550-6150, E-ISSN 1072-6691, Vol. 2006, s. 1-8, artikel-id 135Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this note we consider bifurcation of positive solutions to the semilinear elliptic boundary-value problem with critical Sobolev exponent -∆u = λu - αu^p+ u^{2^*-1}, u ≥ 0, in Ω u=0, on Ω. where Ω is a bounded C^2-domain in R^n, n ≥ 3, λ > λ_1, 1 < p < 2^* -1= (n+2)/(n-2) and α > 0 is a bifurcation parameter. Brezis and Nirenberg showed that a lower order (non-negative) perturbation can contribute to regain the compactness and whence yields existence of solutions. We study the equation with an indefinite perturbation and prove a bifurcation result of two solutions for this equation.

  • 17.
    Cheng, Yuanji
    et al.
    Malmö högskola, Teknik och samhälle (TS).
    Wang, Lina
    Mathematical Center, Lund University, Box 118, 221 00 Lund, Sweden.
    Remarks on bifurcation in elliptic boundary value problems2005Ingår i: International Conference on Differential Equations, World Scientific, 2005, s. 1051-1055Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present some observations of biurcation in nonlinear elliptic boundary value problem - ∆u = f(λ, u) in domain Ω, and u = 0 on the boundary ∂Ω. We are interested in how solution(s) depends on the parameter λ. Through examples, we show that multiple solutions appear, when λ cross certain critical value, i.e. bifurcation occurs.

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  • 18.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Multiple solutions for prescribed boundary value problem2002Ingår i: Nonlinear Analysis, ISSN 0362-546X, E-ISSN 1873-5215, Vol. 51, nr 3, s. 537-552Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We, in this paper, consider the semilinear elliptic boundary value problem - ∆u = f(x, u) in Ω and u = g on ∂Ω and the corresponding Bolza problem x'' + ∂V(t, x) =0, x(0)= x0, x(T)= x1, where Ω is a bounded open subset in R^n with C² boundary and g is a given continuous function on the boundary of Ω; and T is the given traveling time, x0,x1 are two fixed points in the state space Rn. Under certain conditions on f and V, we show that the above problems have infinitely many solutions

  • 19.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Boundary blow-up insemilinear elliptic problems with singular weights at the boundary2001Ingår i: Applicable Mathematics: its perspectives and challenges / [ed] Jagadis Chandra Misra, Narosa publishing house, New Delhi , 2001, s. 68-81Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    In this paper, we study under what conditions on m(x) and f(u) the problem Δu=m(x)f(u) has a solution in a bounded domain D, which tends to infinity, as x tends to the boundary. We show that if m(x) is singular at the boundary of D, except that the Keller-Osserman condition must hold, the growth of f at the infinity has to be slow for a solution to exist. Some existence results have been established.

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  • 20.
    Cheng, Yuanji
    Malmö högskola, Teknik och samhälle (TS).
    Some surprising results on one-dimensional elliptic boundary value blow-up problem1999Ingår i: Zeitschrift für Analysis und ihre Anwendungen, ISSN 0232-2064, E-ISSN 1661-4534, Vol. 18, nr 3, s. 525-537Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we consider the one-dimensional elliptic boundary blow-up problem ∆p(u) = f(u), a < x < b, u(a) = u(b) = + ∞. We show that the structure of the solutions can be very rich even for a simple function f, which indicates that a similar results might hold also in higher dimensional spaces.

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