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Recent research has demonstrated that wide-area signals obtained using synchronized phasor measurements could be more effective than local signals in damping inter-area oscillations in large interconnected systems. To transmit wide-area signals for use in controls, communication systems are required. Communication systems are vulnerable to disruptions as a result of which the reliability of the power system could be jeopardized. In order to counteract communication failures, resiliency could be built in either the communication system or the physical system. In this paper an approach is developed to build resiliency in grid controls in the physical system. The resiliency is achieved by robustly designing a novel redundant two-input single-output (TISO) supplementary damping controller (SDC) associated with a static VAr compensator (SVC) that utilizes both a wide-area signal and a local signal to guarantee that the system is stabilized if the wide-area signal is lost. Numerical tests on the IEEE 50-generator test system have demonstrated that the proposed SDC is effective in stabilizing the system and improving grid control resiliency in response to communication failures.

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The Chehugou Mo-Cu deposit, located 56 km west of Chifeng, NE China, is hosted by Triassic granite porphyry. Molybdenite-chalcopyrite mineralization of the deposit mainly occurs as veinlets in stockwork ore and dissemination in breccia ore, and two ore-bearing quartz veins crop out to the south of the granite porphyry stock. Based on crosscutting relationships and mineral paragenesis, three hydrothermal stages are identified: (i) quartz-pyrite-molybdenite Ϯ chalcopyrite stage; (ii) pyrite-quartz Ϯ sphalerite stage; and (iii) quartz-calcite Ϯ pyrite Ϯ fluorite stage. Three types of fluid inclusions in the stockwork and breccia ore are recognized: LV, two-phase aqueous inclusions (liquid-rich); LVS, three-phase liquid, vapor, and salt daughter crystal inclusions; and VL, two-phase aqueous inclusions (gas-rich). LV and LVS fluid inclusions are recognized in vein ore. Microthermometric investigation of the three types of fluid inclusions in hydrothermal quartz from the stockwork, breccia, and vein ores shows salinities from 1.57 to 66.75 wt% NaCl equivalents, with homogenization temperatures varying from 114°C to 550°C. The temperature changed from 282-550°C, 220-318°C to 114-243°C from the first stage to the third stage. The homogenization temperatures and salinity of the LV, LVS and VL inclusions are 114-442°C and 1.57-14.25 wt% NaCl equivalent, 301-550°C and 31.01-66.75 wt% NaCl equivalent, 286-420°C and 4.65-11.1 wt% NaCl equivalent, respectively. The VL inclusions coexist with the LV and LVS, which homogenize at the similar temperature. The above evidence shows that fluid-boiling occurred in the ore-forming stage. d

The Chehugou granite-hosted molybdenum deposit is typical of the Xilamulun metallogenic belt, which is an important Mo–Ag–Pb–Zn producer in China. A combination of major and trace element, Sr and Nd isotope, and zircon U–Pb isotopic data are reported for the Chehugou batholith to constrain its petrogenesis and Mo mineralization. The zircon SIMS U–Pb dating yields mean ages of 384.7 ± 4.0 Ma and 373.1 ± 5.9 Ma for monzogranite and syenogranite and 265.6 ± 3.5 Ma and 245.1 ± 4.4 Ma for syenogranite porphyry and granite porphyry, respectively. The Devonian granites are calc-alkaline with K2O/Na2O ratios of 0.44–0.52, the Permian granites are alkali-calcic with K2O/Na2O ratios of 1.13–1.25, and the Triassic granites are calc-alkaline and alkali-calcic rocks with K2O/Na2O ratios of 0.78–1.63. They are all enriched in large-ion lithophile elements (LILEs) and depleted in high-field-strength elements (HFSEs) with negative Nb and Ta anomalies in primitive mantle-normalized trace element diagrams. They have relatively high Sr (189–1256 ppm) and low Y (3.87–5.43 ppm) concentrations. The Devonian granites have relatively high initial Sr isotope ratios of 0.7100–0.7126, negative ɛNd(t) values of −12.3 to −12.4 and 206Pb/204Pb ratios of 16.46–17.50. In contrast, the Permian and Triassic granitoids have relatively low initial 87Sr/86Sr ratios (0.7048–0.7074), negative ɛNd(t) values of −10.1 to −13.1 and 206Pb/204Pb ratios of 17.23–17.51. These geochemical features suggest that the Devonian, Permian and Triassic Chehugou granitoids were derived from ancient, garnet-bearing crustal rocks related to subduction of the Palaeo-Asian Ocean and subsequent continent–continent collision between the North China and Siberian plates.

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