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Determination of PID Coefficients for the Ascending and Descending System Using Proportional Valve of a Rice Transplanter

  • Siddique, Md. Abu Ayub;Kim, Wan-Soo;Baek, Seung-Yun;Kim, Yeon-Soo;Choi, Chang-Hyun;Kim, Yong-Joo;Park, Jin-Kam
    • Journal of Biosystems Engineering
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    • v.43 no.4
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    • pp.331-341
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    • 2018
  • Purpose: This study was conducted to develop a linear Proportional-Integral-Derivative (PID) control algorithm for the ascending and descending system of a rice transplanter and to analyze its response characteristics. Methods: A hydraulic model using a single-acting actuator, proportional valve and a PID control algorithm were developed for the ascending and descending system. The PID coefficients are tuned using the Ziegler-Nichols (Z-N) method and the characteristics of unit step response are analyzed to select the PID coefficients at various pump speeds. Results: Results showed that the performance of the PID controller was superior in any condition. It was found that the highest settling time and maximum overshoot were less than 0.210 s and 5%, respectively at all pump speed. It was determined that the steady state errors were 0% in all the cases. The lowest overshoot and settling time were calculated to be nearly 2.56% and 0.205 s, respectively at the pump rated speed (2650 rpm). Conclusions: The results indicated that the developed PID control algorithm would be feasible for the ascending and descending system of a rice transplanter. Finally, it would be helpful to plant the seedlings uniformly and improve the performance of the rice transplanter.

Ginsenoside Rb1 increases macrophage phagocytosis through p38 mitogen-activated protein kinase/Akt pathway

  • Xin, Chun;Quan, Hui;Kim, Joung-Min;Hur, Young-Hoe;Shin, Jae-Yun;Bae, Hong-Beom;Choi, Jeong-Il
    • Journal of Ginseng Research
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    • v.43 no.3
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    • pp.394-401
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    • 2019
  • Background: Ginsenoside Rb1, a triterpene saponin, is derived from the Panax ginseng root and has potent antiinflammatory activity. In this study, we determined if Rb1 can increase macrophage phagocytosis and elucidated the underlying mechanisms. Methods: To measure macrophage phagocytosis, mouse peritoneal macrophages or RAW 264.7 cells were cultured with fluorescein isothiocyanate-conjugated Escherichia coli, and the phagocytic index was determined by flow cytometry. Western blot analyses were performed. Results: Ginsenoside Rb1 increased macrophage phagocytosis and phosphorylation of p38 mitogenactivated protein kinase (MAPK), but inhibition of p38 MAPK activity with SB203580 decreased the phagocytic ability of macrophages. Rb1 also increased Akt phosphorylation, which was suppressed by LY294002, a phosphoinositide 3-kinase inhibitor. Rb1-induced Akt phosphorylation was inhibited by SB203580, (5Z)-7-oxozeaenol, and small-interfering RNA (siRNA)-mediated knockdown of $p38{\alpha}$ MAPK in macrophages. However, Rb1-induced p38 MAPK phosphorylation was not blocked by LY294002 or siRNA-mediated knockdown of Akt. The inhibition of Akt activation with siRNA or LY294002 also inhibited the Rb1-induced increase in phagocytosis. Rb1 increased macrophage phagocytosis of IgG-opsonized beads but not unopsonized beads. The phosphorylation of p21 activated kinase 1/2 and actin polymerization induced by IgG-opsonized beads and Rb1 were inhibited by SB203580 and LY294002. Intraperitoneal injection of Rb1 increased phosphorylation of p38 MAPK and Akt and the phagocytosis of bacteria in bronchoalveolar cells. Conclusion: These results suggest that ginsenoside Rb1 enhances the phagocytic capacity of macrophages for bacteria via activation of the p38/Akt pathway. Rb1 may be a useful pharmacological adjuvant for the treatment of bacterial infections in clinically relevant conditions.

Effects of Solution Treatment Temperatures on Microstructure and Mechanical Properties of TIG-MIG Hybrid Arc Additive Manufactured 5356 Aluminum Alloy

  • Zuo, Wei;Ma, Le;Lu, Yu;Li, Shu-yong;Ji, Zhiqiang;Ding, Min
    • Metals and materials international
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    • v.24 no.6
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    • pp.1346-1358
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    • 2018
  • A novel additive manufacturing method with TIG-MIG hybrid heat source was applied for fabricating 5356 aluminum alloy component. In this paper the microstructure evolution, mechanical properties and fracture morphologies of both as-deposited and heat-treated component were investigated, and how these were affected by different heat-treated temperature. The as-deposited microstructure showed dominant equiaxed grains with second phase, and the size of them is coarse in the bottom region, medium in the middle region and fine in the top region owing to different thermal cycling conditions. Compared with as-deposited microstructure, the size of grain becomes large and second phases gradually dissolve in the matrix as heat-treated temperature increase. Different microstructures determine the mechanical properties of component. Results show that average ultimate tensile strength enhances from 226 to 270 MPa and average microhardness increases from 64.2 to 75.3 HV0.1 but ductility decreases from 33 to 6.5% with heat-treated temperature increasing. For all components, the tensile properties are almost the same in the vertical direction (Z) and horizontal direction (Y) due to equiaxed grains, which exhibits isotropy, and the mechanisms of these are analyzed in detailed. In general, the results demonstrate that hybrid arc heat source has the potential to fabricate aluminum alloy component.

Performance of mid-upper arm circumference to diagnose acute malnutrition in a cross-sectional community-based sample of children aged 6-24 months in Niger

  • Marshall, Sarah K;Monarrez-Espino, Joel;Eriksson, Anneli
    • Nutrition Research and Practice
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    • v.13 no.3
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    • pp.247-255
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    • 2019
  • BACKGROUND/OBJECTIVES: Accurate, early identification of acutely malnourished children has the potential to reduce related child morbidity and mortality. The current World Health Organisation (WHO) guidelines classify non-oedematous acute malnutrition among children under five using Mid-Upper Arm Circumference (MUAC) or Weight-for-Height Z-score (WHZ). However, there is ongoing debate regarding the use of current MUAC cut-offs. This study investigates the diagnostic performance of MUAC to identify children aged 6-24 months with global (GAM) or severe acute malnutrition (SAM). SUBJECTS/METHODS: Cross-sectional, secondary data from a community sample of children aged 6-24 months in Niger were used for this study. Children with complete weight, height and MUAC data and without clinical oedema were included. Using WHO guidelines for GAM (WHZ < -2, MUAC < 12.5 cm) and SAM (WHZ < -3, MUAC < 11.5 cm), the sensitivity (Se), specificity (Sp), predictive values, Youden Index and Receiver Operating Characteristic (ROC) curves were calculated for MUAC when compared with the WHZ reference criterion. RESULTS: Of 1161 children, 23.3% were diagnosed with GAM using WHZ, and 4.4% with SAM. Using current WHO cut-offs, the Se of MUAC to identify GAM was greater than for SAM (79 vs. 57%), yet the Sp was lower (84 vs. 97%). From inspection of the ROC curve and Youden Index, Se and Sp were maximised for MUAC < 12.5 cm to identify GAM (Se 79%, Sp 84%), and MUAC < 12.0 cm to identify SAM (Se 88%, Sp 81%). CONCLUSIONS: The current MUAC cut-off to identify GAM should continue to be used, but when screening for SAM, a higher cut-off could improve case identification. Community screening for SAM could use MUAC < 12.0 cm followed by appropriate treatment based on either MUAC < 11.5 cm or WHZ < -3, as in current practice. While the practicalities of implementation must be considered, the higher SAM MUAC cut-off would maximise early case-finding of high-risk acutely malnourished children.

Impact of thermal and chemical treatment on the mechanical properties of E110 and E110G cladding tubes

  • Kiraly, M.;Hozer, Z.;Horvath, M.;Novotny, T.;Perez-Fero, E.;Ver, N.
    • Nuclear Engineering and Technology
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    • v.51 no.2
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    • pp.518-525
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    • 2019
  • The mechanical and corrosion behavior of the Russian zirconium fuel cladding alloy E110, predominantly used in VVERs, has been investigated for many decades. The recent commercialization of a new, optimized E110 alloy, produced on a sponge zirconium basis, gave the opportunity to compare the mechanical properties of the old and the new E110 fuel claddings. Axial and tangential tensile test experiments were performed with samples from both claddings in the MTA EK. Due to the anisotropy of the cladding tubes, the axial tensile strength was 10-15% higher than the tangential (measured by ring tensile tests). The tensile strength of the new E110G alloy was 11% higher than that of the E110 cladding at room temperature. Some samples underwent chemical treatment - slight oxidation in steam or hydrogenation - or heat treatment - in argon atmosphere at temperatures between 600 and $1000^{\circ}C$. The heat treatment during the oxidation had more significant effect on the tensile strength of the claddings than the oxidation itself, which lowered the tensile strength as the thickness of the metal decreased. The hydrogenation of the cladding samples slightly lowered the tensile strength and the samples but they remained ductile even at room temperature.

Surgical correction for Tessier number 7 craniofacial cleft using a medially overcorrected design

  • Ryu, Jeong Yeop;Eo, Pil Seon;Tian, Lulu;Lee, Joon Seok;Lee, Jeong Woo;Choi, Kang Young;Yang, Jung Dug;Chung, Ho Yun;Cho, Byung Chae
    • Archives of Plastic Surgery
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    • v.46 no.1
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    • pp.16-22
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    • 2019
  • Background Various surgical techniques have been used to correct Tessier number 7 craniofacial cleft, which involves macrostomia, ear deformity, and hemifacial microsomia. To achieve symmetrical and satisfactory results in patients with macrostomia, the authors performed a 1-mm medial overcorrection on the cleft side and evaluated the results of this procedure. Methods A retrospective medical record review of patients diagnosed with Tessier number 7 craniofacial cleft from March 1999 to February 2017 was performed. Using clinical photographs, outpatient clinic records, and operative records, information was recorded regarding concurrent congenital anomalies, postoperative complications, and follow-up. Using Photoshop CS2, the length of both sides of the lip was compared. The ratio of these lengths was calculated to evaluate lip symmetry. Results Of the patients treated at the Department of Plastic and Reconstructive Surgery at Kyungpook National University Chilgok Hospital, 11 (male-to-female sex ratio, 7:4) were diagnosed with Tessier number 7 craniofacial cleft. Concurrent congenital anomalies included skin tag, hemifacial microsomia, and cleft palate. The mean duration of follow-up was $78.273{\pm}72.219$ months and the mean ratio of the lengths of both sides of the lip was $1.048{\pm}0.071$. Scar widening occurred as a postoperative complication in some patients. No cases of wound infection, bleeding, or wound dehiscence occurred. Conclusions For the successful correction of macrostomia, plastic surgeons should consider both functional and aesthetic problems of the lip. Adequate repair of the orbicularis oris muscle, skin closure with Z-plasty, and medial overcorrection of the neo-oral commissure led to good results in our patients.

A new approach to classify barred galaxies based on the potential map

  • Lee, Yun Hee;Park, Myeong-Gu;Ann, Hong Bae;Kim, Taehyun;Seo, Woo-Young
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.33.3-33.3
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    • 2019
  • Automatic, yet reliable methods to find and classify barred galaxies are going to be more important in the era of large galaxy surveys. Here, we introduce a new approach to classify barred galaxies by analyzing the butterfly pattern that Buta & Block (2001) reported as a bar signature on the potential map. We make it easy to find the pattern by moving the ratio map from a Cartesian coordinate to a polar coordinate. Our volume-limited sample consists of 1698 spiral galaxies brighter than Mr = -15.2 with z < 0.01 from the Sloan Digital Sky Survey/DR7 visually classified by Ann et al. (2015). We compared the results of the classification obtained by four different methods: visual inspection, ellipse fitting, Fourier analysis, and our new method. We obtain, for the same sample, different bar fractions of 63%, 48%, 36%, and 56% by visual inspection, ellipse fitting, Fourier analysis, and our new approach, respectively. Although automatic classifications detect visually determined, strongly barred galaxies with the concordance of 74% to 86%, automatically selected barred galaxies contain different amount of weak bars. We find a different dependence of bar fraction on the Hubble type for strong and weak bars: SBs are preponderant in early-type spirals, whereas SABs are in late-type spirals. Moreover, the ellipse fitting method often misses strongly barred galaxies in the bulge-dominated galaxies. These explain why previous works showed the contradictory dependence of the bar fraction on the host galaxy properties. Our new method has the highest agreement with visual inspection in terms of the individual classification and the overall bar fraction. In addition, we find another signature on the ratio map to classify barred galaxies into new two classes that are probably related to the age of the bar.

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A Study on "A Midsummer Night's Palace" Using VR Sound Engineering Technology

  • Seok, MooHyun;Kim, HyungGi
    • International Journal of Contents
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    • v.16 no.4
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    • pp.68-77
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    • 2020
  • VR (Virtual Reality) contents make the audience perceive virtual space as real through the virtual Z axis which creates a space that could not be created in 2D due to the space between the eyes of the audience. This visual change has led to the need for technological changes to sound and sound sources inserted into VR contents. However, studies to increase immersion in VR contents are still more focused on scientific and visual fields. This is because composing and producing VR sounds require professional views in two areas: sound-based engineering and computer-based interactive sound engineering. Sound-based engineering is difficult to reflect changes in user interaction or time and space by directing the sound effects, script sound, and background music according to the storyboard organized by the director. However, it has the advantage of producing the sound effects, script sound, and background music in one track and not having to go through the coding phase. Computer-based interactive sound engineering, on the other hand, is produced in different files, including the sound effects, script sound, and background music. It can increase immersion by reflecting user interaction or time and space, but it can also suffer from noise cancelling and sound collisions. Therefore in this study, the following methods were devised and utilized to produce sound for VR contents called "A Midsummer Night" so as to take advantage of each sound-making technology. First, the storyboard is analyzed according to the user's interaction. It is to analyze sound effects, script sound, and background music which is required according to user interaction. Second, the sounds are classified and analyzed as 'simultaneous sound' and 'individual sound'. Thirdly, work on interaction coding for sound effects, script sound, and background music that were produced from the simultaneous sound and individual time sound categories is done. Then, the contents are completed by applying the sound to the video. By going through the process, sound quality inhibitors such as noise cancelling can be removed while allowing sound production that fits to user interaction and time and space.

Three-dimensional analysis of facial asymmetry after zygomaticomaxillary complex fracture reduction: a retrospective analysis of 101 East Asian patients

  • Cho, Jakwang;Kim, Youngjun;Choi, Youngwoong
    • Archives of Craniofacial Surgery
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    • v.22 no.3
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    • pp.148-153
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    • 2021
  • Background: The zygomaticomaxillary complex (ZMC) has a protruded, convex shape and plays a vital role in determining the contour by affecting the width of the middle face. This study aimed to evaluate the efficiency of ZMC fracture reduction and explore detailed directions for outcome improvement. Methods: We conducted a retrospective study of patients diagnosed with unilateral ZMC fracture who underwent ZMC reduction surgery at a single hospital between January 2015 and May 2020. The primary outcome variable was facial asymmetry using the difference in the bilateral malar eminence (ME) position measured by computed tomography scan. The 3-dimensional distance (IA, asymmetry index) and the distance in each dimension, Dx (anteroposterior distance), Dy (mediolateral distance), and Dz (superoinferior distance) were compared. Results: A total of 101 patients with ZMC fractures and 54 non-fracture patients were enrolled in the study. The mean age of the study sample was 43.49 years (control sample, 43.35 years), and the male-to-female ratio was 66.3:33.7 (control sample, 64.8:35.2). There were 53 and 48 patients with right and left ZMC fractures, respectively. The IA was not statistically different between the two groups. In terms of position in each dimension, only Dx was significantly different between the two groups. Conclusion: The results show that overall facial asymmetry was recovered after ZMC reduction, but in certain dimension significant difference in ME position has still remained. For further improvement, treatment should be performed to relieve malar depression in the anteroposterior dimension.

Retrospective and Prospective Determination of the Cow's Milk-Related Symptom Score (CoMiSSTM) Values in Symptomatic Infants

  • Kozlowska-Jalowska, Anna;Horvath, Andrea;Vandenplas, Yvan;Szajewska, Hania
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.24 no.4
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    • pp.384-391
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    • 2021
  • Purpose: The Cow's Milk-related Symptom Score (CoMiSSTM) was developed as an awareness tool for evaluating cow's milk-related symptoms in otherwise healthy children. Using a convenience sample of participants, this cross-sectional study aimed to determine CoMiSSTM values of symptomatic infants based on retrospectively or prospectively obtained information. Methods: CoMiSSTM values were determined in infants aged <12 months with symptoms suggestive of cow's milk protein allergy or functional gastrointestinal disorders. The exclusion criteria were previous diagnosis with acute or chronic disease, treatment with a therapeutic formula, and in case of breastfeeding, an elimination diet followed by the mother. Two CoMiSSTM values were assessed. A retrospective collection was defined as the collection of data after initial contact with the medical center but before the first medical consultation. A prospective collection was defined as the collection of data within 24 hours from the time of medical consultation but before starting any therapeutic intervention. The CoMiSSTM total and individual component scores obtained retrospectively or prospectively were compared between groups using the Wilcoxon signed-rank test. Results: This study was performed between August and November 2019. Data of 110 children (62 males and 48 females), with a mean±standard deviation age of 18.2±11.7 weeks, were obtained. The total CoMiSSTM value (p<0.001) and some individual component scores (crying, regurgitation, and stool) were significantly lower when collected prospectively than when collected retrospectively. Conclusion: CoMiSSTM values were retrospectively and prospectively determined. Lower CoMiSSTM values were obtained during prospective evaluation. Possible differences should be considered when using CoMiSSTM in clinical practice.