#norelated [[Eng Page]] Consder &ref(prob.gif,left);, where &ref(lam.gif,center); is a bifurcation parameter, &ref(q1.gif,center); is a given exponent, and &ref(mx.gif,center); is positive somewhere in &ref(ome.gif,center); and indefinite, meaning that &ref(mx.gif,center); is a sign-changing function in &ref(ome.gif,center);. It is remarkable in the case of indefinite weifghts that there are possibly two bifurcation points of &ref(lam.gif,center); from the line &ref(u0.gif,center);, whereas in the positive definite case of &ref(mx.gif,center);, we have a unique bifurcation point &ref(lam0.gif,center);. The objective of our study is to consider the existence and behavior of components consisting of positive solutions of the problem that bifurcate from the trivial line. Uniqueness and stability of positive solutions on the components are also studied. ''Keywords'' Nonlinear ellitpic boudary value problem Nonlinear boundary condition Indefinite weight Variational method Super-subsolution degree theory bifurcation A priori bound Uniqueness and multiplicity of positive solutions Population dynamics Incoming flux on the boundary /////////////////////////////////////////////////// RIGHT:今日のアクセス数 &counter(today); RIGHT:昨日のアクセス数 &counter(yesterday); RIGHT:総アクセス数 &counter(total);