Diversifying Question Generation over Knowledge Base via External Natural Questions

Previous methods on knowledge base question generation (KBQG) primarily focus on enhancing the quality of a single generated question. Recognizing the remarkable paraphrasing ability of humans, we contend that diverse texts should convey the same semantics through varied expressions. The above insights make diversifying question generation an intriguing task, where the first challenge is evaluation metrics for diversity. Current metrics inadequately assess the above diversity since they calculate the ratio of unique n-grams in the generated question itself, which leans more towards measuring duplication rather than true diversity. Accordingly, we devise a new diversity evaluation metric, which measures the diversity among top-k generated questions for each instance while ensuring their relevance to the ground truth. Clearly, the second challenge is how to enhance diversifying question generation. To address this challenge, we introduce a dual model framework interwoven by two selection strategies to generate diverse questions leveraging external natural questions. The main idea of our dual framework is to extract more diverse expressions and integrate them into the generation model to enhance diversifying question generation. Extensive experiments on widely used benchmarks for KBQG demonstrate that our proposed approach generates highly diverse questions and improves the performance of question answering tasks.Comment: 12 pages, 2 figure

The thermal damaging process of diorite under microwave irradiation

Laboratory tests have been conducted to investigate the effects of thermal damage on diorite under microwave irradiation. The sample rocks were heated to high temperature range of 300 to 800 ℃ in a single-mode microwave furnace. The experimental results show that the rocks started to crack at 500 ℃ and completely disintegrated at 700 ℃. The intensities of quartz diffraction peaks were almost unchanged while the diffraction peak intensity of hornblende gradually decreased with temperature increasing. In addition, the chlorite diffraction peak disappeared at 500 ℃. The compressive strength of the sample decreased to 40% at 600 ℃ and it approached zero at 700 ℃. In this paper, the possible reasons for the thermal effects on the fracture of diorite were discussed, which can be related to water evaporation, thermal cracks and mismatch thermal expansion, and phase transition on quartz. The result indicates that diorite can be effectively destroyed under microwave irradiation

Effects of estradiol on fatty acid composition and tissue structure of hepatopancreas in <em>Procambarus clarkii</em>

The hepatopancreas of Procambarus clarkii provides lipids and other nutrients for ovarian development and contains hormones such as estradiol related to ovarian development. During the development of the P. clarkii ovary, the hepatopancreas' tissue structure and fatty acid content undergo corresponding changes. A controlled indoor experiment was conducted to investigate the effects of exogenous estradiol injection on the tissue structure and fatty acid content in the hepatopancreas of P. clarkii. The experiment consists of three experimental groups and one control group. The P. clarkii in the experimental group were injected with 5, 0.5, and 0.05 μg/(g body weight) of estradiol once every 5 days for 5 times and with normal saline injection as the control. After 25 days, the content of fatty acids and changes in tissue structure in the hepatopancreas were measured. The results showed that the main fatty acids in P. clarkii hepatopancreas were C18:4n, C20:3n, and EPA, and polyunsaturated fatty acid (PUFA) content was 57.17%±4.76%. Injecting estradiol mainly affected the content of C16:0, C16:1n, C18:0, C18:1n9, C18:2n, C18:3n6, C18:3n6, C18:4n, C20:1n, C20:2n, C20:3n, C20:4n3, C20:5n3, C22:n (n=1-4), C22:5n, and C22:6n in the hepatopancreas. Injecting estradiol significantly reduced the total content of PUFA in hepatopancreas with the reduction of C18:3n6, C18:4n, C20:3n, C20:4n3, C20:5n3 C22: n (n=1-4) (P<0.05); Estradiol injection significantly increased the total content of monounsaturated fatty acid (MUFA) in hepatopancreas with the increase of C18:1n9, and C20:1n (P<0.05); Injection of estradiol (0.05 μg/g) significantly increased the total content of saturated fatty acids (SFA) in the hepatopancreas (P<0.05) with the increase of C16:0 and C18:0 (P<0.05). Injecting estradiol can increase the volume and quantity of hepatopancreatic B cells, and the 5 μg/g group had the most obvious changes

Tunable and absolute electromagnetic vacuum in two-dimensional photonic-band-gap Based on multiferroic materials

When multiferroic terbium manganite (TbMnO₃) crystal cylinders are periodically arranged in a square lattice, the resulting two-dimensional (2D) system exhibits photonic band gaps (PBGs). The absolute PBG originating from the Mie resonance is modulated from closed to open by applying an external static magnetic field, which is attributed to the electromagnon depression of the dielectric constant by the rearrangement of antiferromagnetic order. Tunable electromagnetic band structure may be realized by controlling the magnetic transition of manganese spins in TbMnO₃.The authors are grateful for financial support from the Outstanding Foundation of NJUST, the NJUST Research Funding (No. 2010ZDJH06), the National Natural Science Foundation of China (Grant Nos. 11004106, 50672034, 50832002, and 50901042), and the State Key Program for Basic Research of China (Grant Nos. 2009CB623303 and 2009CB929501)

Negative magnetodielectric effect in CaCu₃Ti₄O₁₂

Real part of complex relative dielectric value is relatively decreased as large as  ∼5 % from 50 K to 200 K in CaCu₃Ti₄O₁₂, by applying a 6-T static magnetic field. CaCu₃Ti₄O₁₂ is thus implied primarily by the negative magnetodielectric effect, as a unified dielectric system in which 1-D finite dipole chains of B-site titanium ions, coexist with a collective of polaron-like 3d-electrons of A-site copper ions: the dipole chains are thermally activated for lattice ionic polarization above 50 K, and suppressed by the short-range hop of these quasi-particles, while their long-range movement are for bulk electronic polarization above 151 K.This work was supported by the National Natural Science Foundation of China (Grant No. 11004106) and the National 973 Project (Nos. 2011CB922101 and 2009CB623303)

Comparative study on the deterioration of granite under microwave irradiation and resistance-heating treatment

To investigate the deterioration of granite under microwave irradiation and heat transfer, granite specimens were heated up to 400-1000 °C and then kept for 15 min. Uniaxial compressive strength testing results demonstrate a similar variation in two groups in 400-900 °C, which is initial strengthening (less than 500 °C), subsequent weakening (500-600 °C) and final stabilizing (600-900 °C). Furthermore, the specimen irradiated by microwaves presented a second decline at 1000 °C. Compared to heat transfer, microwave irradiation can reduce the strengthening due to localized transition plasticity and further promotes the deterioration of rock structure in weakening stage. TG/DSC results indicate that the strengthening is related to the iron mineral transition. The formation of porous glass substance which is mainly composed of feldspar and biotite. Furthermore, temperature-controlled microwave irradiation induced the variation of feldspar crystallinities, which is consistent with the corresponding UCS data, especially the plagioclase. In practical application, microwaves can be used to irradiate the vulnerable positions (surface edge and cleavage) and kept the whole rock mass around 600 °C