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"This timely revision provides an up-to-date collection of the research on crime prevention. The prevailing approaches and strategies are organized into categories of primary prevention (designed to prevent conditions that foster deviance), secondary prevention (directed toward persons or conditions with a high potential for deviance), and tertiary prevention (dealing with those who have already committed offenses). The effects of physical environments, the mass media, displacement and diffusion, electronic monitoring, and home confinement are also explored. In addition to presenting a discussion of the different prevention approaches, the author provides insight into the effectiveness of each approach. Features: a new chapter on developmental crime prevention focuses on the early life experiences that predispose individuals to commit deviant acts and using risk factors in predicting behaviour for secondary prevention; new attention is brought to situational prevention, partnerships for crime prevention, the politics of prevention strategies, and the tangential topic of organizing dysfunctional neighbourhoods; and all chapters now include updated tables that indicate the state of the evidence as well as key terms, learning objectives, web references, and a helpful glossary."

"Sebuah sistem kuantum terbuka rentan terhadap dekoherensi. Pada sebuah nitrogen-vacancy (NV) center qubit, dekoherensi disebabkan karena noise acak pada frekuensi Larmor yang muncul akibat interaksi dengan spin bath di sekitarnya. Peluruhan yang terjadi bersifat Gaussian, yang berarti proses ini secara matematik dapat dimodelkan dengan proses Ornstein-Uhlenbeck (OU). Kalkulasi teoretik dilakukan untuk menentukan parameter OU yang cocok berdasarkan besaran yang diperoleh dari eksperimen. Penulis mempelajari efek delta noise yang mengakibatkan dekoherensi dan menemukan bahwa ia mengganggu pulsa dengan durasi panjang. Sementara itu, ketidakpastian amplitudo kontrol, yang disebut epsilon noise dan dimodelkan pula dengan proses OU, bertanggung jawab mengakibatkan dephasing pada pulsa kontrol, yang menganggu operasi dengan banyak pulsa. Bersama-sama, keduanya mengganggu operasi qubit sebagaimana ditunjukkan dengan hasil simulasi beberapa dynamical decoupling (DD) sequences. Untuk melawan efek dari kedua OU noise ini, penulis mempelajari performa algoritma quantum optimal control (QOC) yang bernama Dressed Chopped Random Basis (dCRAB) dalam membentuk pulsa kontrol, dengan meminimasi sebuah cost function yang dirumuskan dengan sesuai. Pengurangan cost function rata-rata sebesar 37% diperoleh dengan optimisasi cepat dari pulsa kontrol. Pulsa-pulsa teroptimisasi ini, dipalikasikan pada DD sequences yang sama, menunjukkan peningkatan performa yang lebih dekat dengan versi idealnya.

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Open quantum systems are vulnerable to decoherence. In a nitrogen-vacancy (NV) center qubit, decoherence is caused by a random noise on the Larmor frequency resulting from the interaction with the surrounding spin bath. The resulting decay is Gaussian, which suggests that the Ornstein-Uhlenbeck (OU) process may be used to model the decoherence mathematically. A theoretical calculation is done to find the appropriate OU parameters based on experimentally obtained quantities and serves as the foundation for the numerical simulations. The author studies the effect of the decoherence-inducing delta noise and finds that it interrupts pulses with long durations. Meanwhile, the pulse amplitude uncertainty, called the epsilon noise and likewise modeled as an OU process, is responsible for the dephasing of control pulses, interrupting the qubit for operations with many pulses. Together, these noises interrupt the qubit operations, as exhibited by the simulation results of several dynamical decoupling (DD) sequences. To counteract the effect of the OU noises, the author studies the performance of the Dressed Random Choppedc Basis (dCRAB) quantum optimal control (QOC) algorithm in shaping the control pulses, by minimizing an aptly formulated cost function. An average cost function reduction of 37% is obtained from quick optimizations of the control pulses. These optimized pulses, applied to the same DD sequences, show increased performance closer to the ideal version."