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W podziemnym górnictwie węgla wentylacja odgrywa ważną rolę, ponieważ zapewnia wystarczającą ilość świeżego powietrza dla pracowników i zmniejsza negatywne skutki uwalniania się szkodliwych gazów z pokładów węgla oraz możliwość wystąpienia wybuchów. Ponadto, gdy eksploatacja sięga głębiej, zadanie wentylacji jest coraz ważniejsze. W celu zagwarantowania dobrej wydajności wentylacji do obliczeń sieci wentylacyjnej stosuje się oprogramowanie symulacyjne. W artykule przedstawiono zastosowanie oprogramowania Ventsim DESIGN dla obliczenia sieci wentylacyjnej kopalni Duong Huy oraz przewidywania dróg ewakuacyjnych w nagłych przypadkach. Wyniki symulacji pokazują, że program dobrze wylicza wydajność sieci , warunki stabilnej pracy oraz odpowiednie drogi ewakuacyjne w nagłych przypadkach.

Additional file 1: Figure S1. Comparison of core-level spectra for SnSe with or without the photoemission charging effect. Figure S2. ARPES E-k dispersions along the Γ-Y direction for SnSe single crystals with different growth cooling rates.

Mục tiêu: Nghiên cứu này được thực hiện nhằm đánh giá kết quả trung hạn ứng dụng kỹ thuật can thiệp đặt ống ghép nội mạch điều trị phình động mạch chủ bụng dưới thận. Đối tượng và phương pháp nghiên cứu: Nghiên cứu mô tả dọc tiến cứu. Đối tượng là bệnh nhân phình động mạch chủ bụng dưới thận có kèm hoặc không kèm theo phình động mạch chậu tại khoa Phẫu thuật Mạch máu Bệnh viện Chợ Rẫy, trong thời gian từ tháng 5/2012 đến tháng 8/2017 được điều trị bằng can thiệp nội mạch. Kết quả: Có tất cả 95 trường hợp (71 nam và 24 nữ) đủ tiêu chuẩn đưa vào nghiên cứu. Tuổi trung bình là 73,8 ± 17,6 tuổi. Thời gian theo dõi trung bình là 33 ± 19 tháng. Tỷ lệ rò nội mạch muộn là 6,3%. Không có trường hợp nào di lệch ống ghép, 6 trường hợp cần can thiệp lại. Tỷ lệ tử vong trung hạn là 21,1% trong đó có 2 trường hợp (2,1%) tử vong liên quan đến túi phình. Kết luận: Tỷ lệ tử vong trung hạn và tỷ lệ can thiệp lại trung hạn của can thiệp nội mạch động mạch chủ đều ở mức ngang bằng hoặc cao hơn so với phẫu thuật mở. Như vậy, can thiệp nội mạch động mạch chủ rất có lợi trên những bệnh nhân lớn tuổi, nhiều bệnh kèm và yếu tố nguy cơ.

In this paper, we obtain strong laws of large numbers for triangular array of row-wise exchangeable random sets and fuzzy random sets in a separable Banach space in the Mosco sense. Our results are...

The structural, vibrational, optical, ferroelectric, and ferromagnetic properties of single phase BiFeO3 (BFO) and Bi1-xGdxFe0.975Ni0.025O3 (x ~ 0.00, 0.025, 0.05, 0.075, 0.10, 0.125, and 0.15) materials, synthesized by sol-gel method have been investigated systematically using different techniques. X-ray diffraction patterns (XRD) revealed that all samples crystallized in single phase and showed a compressive lattice distortion with increasing Gd-doping concentration. A structural phase transition from rhombohedral to orthorhombic took place at co-doped sample with x = 0.125 which was evidenced by both XRD analyses and Raman scattering spectra. Optical band gap was slightly decreased with Gd-doping content. Ni and Gd co-substitution in BFO caused a remarkable enhancement of both ferroelectric and ferromagnetic properties which was demonstrated by the sharp increasing of maximum (Ps) and remnant (Pr) polarization, dielectric constant (e), saturation (Ms) and remnant (Mr) magnetization. Our results indicated the effective contributions of Ni-doping and Gd-doping in the innovations of ferromagnetism and ferroelectricity of BFO, respectively.

Introduction The purpose of this study was to analyse the outcomes of endovascular aneurysm repair (EVAR) in patients with aortic aneurysms with short and angulated aortic neck. Methods This was a retrospective case series of single centre experience. Patients diagnosed with infrarenal abdominal aneurysm with or without iliac aneurysm who underwent endovascular treatment between May 2012 and August 2020 were included in the study. Results Standardised information of 95 patients who met the inclusion criteria was documented (71 males, 24 females; average age: 73.8 ± 17.6 years). There were 45 patients in group H (short and/or angulated aortic neck anatomy) and 54 patients in group F (control group). The clinical presentations, intervention-related characteristics, and early as well as mid-term results were not statistically different between the two groups. In group H, cases of short aortic neck had higher risk of early type IA endoleak (4 patients, 57.1%). Conclusion Endovascular aneurysm repair in the treatment of infrarenal abdominal aortic aneurysm is considered safe and effective in cases of both groups. Treatment outcomes and complications were not statistically different between the groups. Nevertheless, cases of aortic short neck had a greater risk of early type IA endoleak and reintervention.

Methane gas is one of the most serious dangers of undergroundcoal mining as its buildup can lead to methane gas explosion. InQuangNinh province- Vietnam, several coal mines such as TrangKhe II-IIIcoal mine, Khe Cham coal mine, especially MaoKhe mine that have highmethane content. At the MaoKhe coal mine,experimental data showedthatthe concentration of methane in coal seams at different depths were notsimilar.In order to ensure safety, this report has been undertaken todetermine a pattern of changing methane contents of coal seams atdifferent exploitation depths in MaoKhe underground coal mine.

The aim of this study is to provide some strong limit theorems for weighted sums of measurable operators. The almost uniform convergence and the bilateral almost uniform convergence are considered. As a result, we derive the strong law of large numbers for sequences of successively independent identically distributed measurable operators without using the noncommutative version of Kolmogorov’s inequality.

In this study, red-emitting AlPO4:Cr3+ phosphors have been successfully synthesized by a facile sol-gel method. The Tanabe–Sugano diagram demonstrates that the surrounding sites of Cr3+ ions has a high crystal field with Dq/B=2.47. The sharp 694-nm peak on the PL of AlPO4:Cr3+ phosphor could be attributed to the 2E→4A2 electron transition of Cr3+ ions. The AlPO4:0.3%Cr3+ phosphor presents the highest PL intensity, then a purple LED prototype is obtained by coating the optimum powder on a UV LED chip. The color coordinates (0.2412, 0.1330) of the purple LED prototype implies that AlPO4:Cr3+ phosphors are promosing to be used as deep red phosphor powder for horticulture LED lighting.

Although it has been extensively studied for decades, the α-Al

In this paper, we introduce the notions of uniform integrability in the Cesaro sense, h-integrability with respect to the array of constants {ani}, and h-integrability with exponent r for an array of measurable operators. Then, we establish some mean convergence theorems and weak laws of large numbers for arrays of measurable operators under some conditions related to these notions.