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Boosting machining quality is a prominent solution to save production costs for burnishing operations. In this work, a machining condition-based optimization has been performed to decrease surface roughness (SR) and enhance Vickers hardness (VH) of the minimum quantity lubrication-assisted burnishing operation (MQLABO). The burnishing factors are the spindle speed (S), depth of penetration (D), and the air pressure (P). The burnishing trails of the hardened material labeled 40X have been conducted on a milling machine. The adaptive neuro-based-fuzzy inference system (ANFIS) was used to construct the correlations between the process inputs and MQLABO responses. The non-dominated sorting genetic algorithm-II (NSGA-II) is utilized to determine the optimal parameters. The scientific outcomes revealed that the optimal values of the S, D, and P are 800 RPM, 0.09 mm, and 4.0 Bar, respectively. The SR is decreased by 53.8%, while the VH is enhanced by 3.1%, respectively, as coBarred to the initial values.

BackgroundOf the estimated 10 million people affected by (TB) each year, one-third are never diagnosed. Delayed case detection within the private healthcare sector has been identified as a particular problem in some settings, leading to considerable morbidity, mortality and community transmission. Using unannounced standardised patient (SP) visits to the pharmacies, we aimed to evaluate the performance of private pharmacies in the detection and treatment of TB.MethodsA cross-sectional study was undertaken at randomly selected private pharmacies within 40 districts of Vietnam. Trained actors implemented two standardised clinical scenarios of presumptive TB and presumptive multidrug-resistant TB (MDR-TB). Outcomes were the proportion of SPs referred for medical assessment and the proportion inappropriately receiving broad-spectrum antibiotics. Logistic regression evaluated predictors of SPs’ referral.ResultsIn total, 638 SP encounters were conducted, of which only 155 (24.3%) were referred for medical assessment; 511 (80·1%) were inappropriately offered antibiotics. A higher proportion of SPs were referred without having been given antibiotics if they had presumptive MDR-TB (68/320, 21.3%) versus presumptive TB (17/318, 5.3%; adjusted OR=4.8, 95% CI 2.9 to 7.8). Pharmacies offered antibiotics without a prescription to 89.9% of SPs with presumptive TB and 70.3% with presumptive MDR-TB, with no clear follow-up plan.ConclusionsFew SPs with presumptive TB were appropriately referred for medical assessment by private pharmacies. Interventions to improve appropriate TB referral within the private pharmacy sector are urgently required to reduce the number of undiagnosed TB cases in Vietnam and similar high-prevalence settings.

The study uses the simulating waves nearshore (SWAN) model and ensemble Kalman filter (EnKF) method, which has been integrated in the Open Data Assimilation system, to assimilate wave observation data from the oil platform over the South China Sea - East Sea of Vietnam. A set of experiments with and without EnKF was established based on the different parameters, including ensemble size, standard deviation for the wind noise field, time correlation scale for boundaries updating processes, and the horizontal correlation scale in covariance derivation. Compared to observation and re-analysis European Centre for Medium-Range Weather Forecasts (ECMWF) data, results showed improved forecasts on the significant wave height and other SWAN model variables with data assimilation. The experiments have clearly updated error forecast information of the model (positive bias) to the 24 hour forecast results. The significant sensitivities to both magnitude and distribution for increments of model analysis fields and for forecast results on spatial and time correlation scales show the importance of investigating more suitable EnKF parameters for specific area and observation applications.

File System is an important component of a secure operating system. The need to build data protection systems is extremely important in open source operating systems, high mobility hardware systems, and miniaturization of storage devices that make systems available. It is clear that the value of the data is much larger than the value of the storage device. Computers access protection mechanism does not work if the thief retrieves the hard drive from the computer and reads data from it on another computer. Encrypted File System (EFS) is a secure level of operating system kernel. EFS uses cryptography to encrypt or decrypt files and folders when they are being saved or retrieved from a hard disk. EFS is often integrated transparently in operating system There are many encrypted filesystems commonly used in Linux operating systems. However, they have some limitations, which are the inability to hide the structure of the file system. This is a shortcoming targeted by the attacker, who will try to decrypt a file to find the key and then decrypt the entire file system. In this paper, we propose a new architecture of EFS called KVEFS which is based on cryptographic algorithms, FUSE library and key-value store. Our method makes EFS portable and flexible; Kernel size will not increase in Operating System. &nbsp

Rice straw is an agricultural residue from rice production, which can be a potential lignocellulosic feedstock for various value-added products. In this study, silica was extracted from the rice straw. The biomass was pre-treated with ethanol and was cooked with 18% w/w sodium hydroxide to extract lignin and silica. The silica was precipitated from the alkaline solution using 30% sulfuric acid to pH 11.5 and was recovered through centrifugation. The obtained solid was washed and then combusted at 575 °C for 6 hours. The obtained ash was dissolved in sodium hydroxide solution at pH 8.0 and then re-precipitated by sulfuric acid to form silica powder, which obtained a yield of about 6.7% w/w dry rice straw. The characteristics of amorphous disk-formed silica, determined using XRD, SEM, EDS, and FT-IR.

During the study of the literature, collecting specimens from the field and studying the specimens of Ficus genus in herbarium and international botanical specimens, we found the species: Ficus squamosa, a new record for flora of Vietnam. It is closed to Ficus hispida and chiefly differs in caespitose habit and lateral bracts present on fig body. In this paper, we introduce for this species with a short data on taxonomy, types, morphology, ecology and distribution of the mentioned species accompanied with the photos. The vouchers were collected in Cham Chu special used forest (Tuyen Quang province), preserved in the Herbarium of the Institute of Ecology and Biological Resources, Hanoi, Vietnam (HN) and VNU-University (HNU).

Hymenophyllum Sm. is a largest genus in filmy ferns family, Hymenophyllaceae with around 250 species in the world. A long time ago, its diagnostic feature was bivalved involucres, but in 2006, A. Ebihara et al. combined between morphology method and molecular analyses to propose a new classification of Hymenophyllaceae, therefore, its diagnostic features are rhizomes long-creeping, nearly glabrous or sparsely covered with light-coloured hairs and involucres usually bivalvate. This classification system was accepted to revise 258 collecting numbers of specimens in Vietnam. The results have claimed that Hymenophyllum genus in Vietnam comprised 10 species. Each species was provided taxonomy, distribution in Vietnam, treatment specimens and photos.

Trong quá trình nghiên cứu họ Gừng (Zingiberaceae) ở Bắc Trung Bộ, chúng tôi đã phát hiện và bổ sung loài Zingiber nitens M.F. Mewman cho hệ thực vật Việt Nam, nâng tổng số loài của chi Gừng (Zingiber) lên 34 loài.

Hoàng liên ô rô lá dày (Mahonia bealei (Fortune) Pynaert) (Berberidaceae) là một loài cây thuốc có giá trị cao, loài được ghi nhận có phân bố tự nhiên tại huyện Sa Pa, Bát Xát tỉnh Lào Cai và huyện Quản Bạ tỉnh Hà Giang. Loài này đang bị khai thác mạnh và bị đe dọa nghiêm trọng trong tự nhiên, được đưa vào Sách đỏ Việt Nam, năm 2007 ở mức EN; Hoàng liên ô rô lá dày là cây bụi, có chiều cao từ 0,5 - 2(-4)m. Lá kép lông chim 1 lần lẻ, kích thước lá 25 - 40 x 8 - 13cm, 8-14 cặp lá chét, mép lá chét thường có răng cưa nhọn; Cụm hoa mọc thẳng đứng với 3 - 15 chùm, dài 7 - 26cm. Quả mọng, hình dục 1,1 - 1,4 x 0,8 – 1,0cm, mỗi quả mang 1 - 2 hạt; hạt kích thước 0,6 - 0,8 x 0,4 - 0,5cm; - Cây tái sinh chủ yếu từ hạt; mật độ cây trưởng thành (từ 0,5m trở lên) trong khoảng 418-512 cá thể/ha tại khu vực nghiên cứu. Thời gian ra chồi mới, lá non tập trung vào các tháng từ tháng 7 đến tháng 10 hàng năm, chiều cao tăng trưởng 11,73cm/ năm. - Hoàng liên ô rô lá dày thường mọc dưới tán rừng thưa hay các trảng cây bụi trên núi đá vôi nơi đất có lượng mùn ít, nghèo dinh dưỡng, độ cao từ 1.700- 2.500m, nhiệt độ trung bình khoảng 15 - 16oC, độ ẩm không khí trên 80%, lượng mưa 1.800 - 2.800mm/năm.