浅析objective-c中的strong和weak 在才开始学习oc时,搞不懂什么时候用strong,什么时候用weak,经过一段时间的学习,我谈谈我对strong和weak的理解。 首先strong和weak这两个关键字是用来修饰变量,表示这个变量是强(strong)引用和弱(weak)引用 我们在程序中经常会用到“[[class alloc]init]” 这样的代码,我想你对...
A strong and room-temperature self-healing DCNC/50PEDA vitrimer is created;The room-temperature self-healing efficiency of DCNC/50PEDA reaches 96.0%;The tensile strength of DCNC/50PEDA is up to 36.0MPa;DCNC/50PEDA shows desired closed-loop recyclability;DCNC/50PEDA features exceptional ...
Nature Communications volume 16, Article number: 431 (2025) Cite this article 5752 Accesses 1 Citations 1 Altmetric Metrics details Abstract Stretchable elastic materials with high strength, toughness, and good ionic conductivity are highly desirable for wearable devices and stretchable batteries. Unfort...
Miniaturization of medical tools promises to revolutionize surgery by reducing tissue trauma and accelerating recovery. Magnetic untethered devices, with their ability to access hard-to-reach areas without physical connections, emerge as potential candid
Instead of the certificate file (in our example moonCert.pem), the serial number of the certificate to be revoked can be indicated using the --serial parameter. The pki --signcrl --help command documents all possible revocation reasons but the --reason parameter can also be omitted. The ...
C (2024) 84:574 https://doi.org/10.1140/epjc/s10052-024-12917-0 Regular Article - Theoretical Physics Strong gravitational lensing by Sgr A∗ and M87∗ black holes embedded in dark matter halo exhibiting string cloud and quintessential field Niyaz Uddin Molla1,a, Himanshu Chaudhary2,3,4...
Automated analysis of heart structures in MRI is crucial for effective diagnostics. While supervised learning has advanced the field of medical image segmentation, it however requires extensive labelled data, which is often limited for cardiac MRI. Methods: Drawing on the principle of consistency ...
40 国际基础科学大会-On some open problems in Diophantine Approximation-Nikolai Moshchevitin 1:08:19 国际基础科学大会-Low moments of character sums-Adam James Harper 48:57 国际基础科学大会-Tilting theory revisited-Osamu Iyama 51:53 国际基础科学大会-The chromatic number of random graphs-Annika ...
In general, the parity transformation of a Dirac fermion field, qi (i = 1, . . . , NF ), is defined as P qi(t, x) P = γ0 qi(t, −x), (2.1) using the parity operator P , that satisfies P 2 = 1.1 The Lagrangian density Lq for qi and a scalar Φ is given by Lq ...
关闭ARC:-fno-objc-arc 如图: ARC的修饰符 ARC主要提供了4种修饰符,他们分别是:__strong,__weak,__autoreleasing,__unsafe_unretained。 __strong 表示引用为强引用。对应在定义property时的"strong"。所有对象只有当没有任何一个强引用指向时,才会被释放。