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Risk in a power system's ability to survive imminent disturbances without recourse to low operational cost and non-interruptive energy delivery remains the responsibility of every grid operator. Intermittencies in renewable energy and dynamic load variations influence the quality of power supply. The sudden changes affect the system frequency, compromising the reliability of the system grid, generation response to frequency regulation is momentous in such an incident. Slower response or smaller reserve capacity may cause a power shortage. This paper proposes a novel predictive scheme for a short-term operational reliability evaluation for system operations planning. The proposed method evaluates the operational reliability of system frequency whiles considering high renewable power penetration and energy storage system incorporation. Required energy generations, and other grid parameters, are modelled as stochastic inputs to the framework. We formulate a reliability index as a frequency distribution considering system frequency control dynamics and processes. The IEEE Reliability Test System (RTS) is used to prove the efficacy of the proposed model.

It is known that multiple zeta values can be written in terms of certain iterated log-sine integrals. Conversely, we evaluate iterated log-sine integrals in terms of multiple polylogarithms and multiple zeta values in this paper. We also suggest some conjectures on multiple zeta values, multiple Clausen values, multiple Glaisher values and iterated log-sine integrals., Comment: 22 pages

We introduce an iterated integral version of (generalized) log-sine integrals (iterated log-sine integrals) and prove a relation between a multiple polylogarithm and iterated log-sine integrals. We also give a new method for obtaining relations among multiple zeta values, which uses iterated log-sine integrals, and give alternative proofs of several known results related to multiple zeta values and log-sine integrals., Comment: 18 pages

T. Ito defined an analog of the Arakawa-Kaneko zeta function to obtain relations among Mordell-Tornheim multiple zeta values. In this paper, we develop two things related to an analog of the Arakawa-Kaneko zeta function. One is to find an analog of the Arakawa-Kaneko zeta function of Miyagawa-type (defined by T. Miyagawa) and to obtain a relation among Miyagawa-type MZVs. The other is to find a class of zeta functions to which Ito's zeta functions of the case of general index are related., Comment: 23 pages

Highly diastereo- and enantioselective cyclopropanation of aromatic α,β-unsaturated aldehydes was achieved using a resin-supported peptide catalyst under aqueous conditions. In the peptide sequence, the residue possessing an oxygen atom with the appropriate length of the side chain was essential for attaining good diastereoselectivity.

In this work, we provide a completely new approach for a short-term power system reliability that can be utilized for system operation planning. The proposed index incorporates the system frequency as a reliability of the grid and its deviation over a short time period. Although frequency performance is often employed as a quality metric for the past system operation, our model can address the future system condition by forecasting the statistics of the system frequency for a specific operation condition. In our model, demand, renewable source, battery and generators are stochastically incorporated. Using the equilibrium of demand and supply, and the physical constraints of automatic generation control (AGC), a model is developed, from which the system frequency distribution is obtained. From the contrived system frequency, statistical function, referred to herein as Frequency Reliability Distribution Function (FRDF), is proposed from which various criteria could be developed for short-term reliability. The developed FRDF along with the pertaining metrics are utilized for some case studies with IEEE reliability test system.

In this work, we provide a new short-term reliability index that accounts for practical grid properties. The proposed index addresses the system frequency reliability and controllability of the grid and its deviation over a short time period. In the formulation, demand, renewable source, battery and generators are incorporated in stochastic manner. Using the equilibrium of demand and supply, and the physical constraints of automatic generation control (AGC), a model is developed, from which the system frequency distribution is obtained. From the contrived system frequency statistical function, referred to as Frequency Reliability Distribution Function (FRDF), various criteria can be developed for short-term reliability. The developed FRDF along with the pertaining metrics are utilized for some case studies with IEEE reliability test system.

The new method can also be applied to aliphatic acrylaldehydes giving products with low diastereoselectivity (no examples are shown).

In the presence of a peptide catalyst and the oxidative enzyme laccase, a one-pot sequential reaction including a Friedel–Crafts-type alkylation of α,β-unsaturated aldehydes followed by an α-oxyamination was realized. The reaction in aqueous solvent to promote the enzymatic oxidation, and the use of a peptide catalyst compatible with such conditions, were essential. The present sequential reaction afforded oxygen-functionalized indole or pyrrole derivatives in a highly enantioselective manner.