• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.751-759
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• 2008

In this study, the effect of an unsteady flow field around a body of aerostatic/aerodynamic forces were investigated using rectangular cylinders (B/D = 2, 3, 4, 5). Proper orthogonal decomposition (POD) was introduced to the analysis of the fluctuating pressure field that was measured on the stationary/oscillatory B/D=4 rectangular cylinder, and the characteristics of the proper functions with flow patterns were identified. In addition, the physical decoupling and interactions in the different co-existing flow patterns were investigated through POD. The comparison with the identified proper function associated with a particular flow pattern revealed that the Karman vortex is almost not affected by the separation bubble, but that the Karman vortex considerably interferes in the development of the separation bubble around the trailing edge. It can be considered that the Karman vortex induces the increment of the curvature of the substantial separated flow.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.6
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• pp.567-575
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• 2013

A POD analysis based on time-resolved PIV measurements in a circulating water channel has been conducted to identify the skin friction reduction mechanism of outer-layer vertical blades. A recent PIV measurement indicated 2.73% and 7.95% drag reduction in the blade plane and the blade-in-between plane, respectively. In the present study, the influence of vertical blades array upon the characteristics of the turbulent coherent structures was analyzed by the POD method. It is observed that the vortical structures are cut and deformed by the blades array and that their temporal evolution is strongly associated with the skin-friction drag reduction mechanism in the turbulent boundary layer flow.

• Journal of Ginseng Research
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• v.21 no.1
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• pp.43-48
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• 1997

Dynamic parameters of biochemistry including the POD (peroxidase) activity, contents of DNA and RNA, isozymes of POD and ES (esterase) in American send (Panax quinquefolium L.) seed are reported in the present paper. The dynamic changes of POD activity proved that the PAS (physiological afterripening stage) is a stage in which some substances are prepared for seed germination. The POD activity correlated with ER (embryo ratio) significantly DNA content changed little only within 0.0036∼0.013 mg/ml, which did not correlate with ER. RNA content changed from 0.1539 to 1.0313 mg/ml and correlated significantly with RE during all of the embryo afterripening. None of the POD isozyme band was obtained in ESGS (embryo slowly growth stage), but five bands in ERGS (embryo rapidly growth stage) and six bands in PAS. Four bands of ES isozymes were obtained in ESGS, but six bands in ERGS, particularly, the content of ES isozymes increased in PAS. All of these may provide some information for understanding the dormancy mechanisms of American song seed.

• Journal of Biosystems Engineering
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• v.27 no.2
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• pp.89-96
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• 2002

The trend of consumption of vegetable soybeans is increasing because they are recognized as the clean vegetable. The works requiring the most intensive labor are threshing and seperation ones, and they form about 80% of total labour for vegetable soybeans production. It is necessary to develop the vegetable soybeans-thresher for the sake of cost down of vegetable soybeans production. The purpose of this study is to acquire the basic informations to design of the vegetable soybeans-thresher. We make the experimental system which control the speed of threshing cylinder and the teeth gap and investigate the detachment forces. The result are as follows ; The ratio of un-threshed soybeans-pod to stem after threshing work is decreasing as the threshing cylinder speed increases: 0.0% and 2.8% at 55m/s and 18m/s of threshing cylinder speed respectively. Also the ratio of un-threshed soybeans-pod to stem is shown as 2.0% below in the condition of 64~160mm of teeth gap and over 28m/s of threshing cylinder speed. The damaged pod ratio of detached soybeans after threshing work is decreasing as the threshing cylinder speed increases: 4.8% and 1.3% at 55m/s and 18m/s of threshing cylinder speed respectively. The minimum damaged pod ratio of detached soybeans are shown as 1.0%, 1.5% and 1.9% at 18m/s, 28m/s and 37m/s of threshing cylinder speed respectively. The average detachment forces of pods are shown as 1.5kg$_{f}$ for 3 grains, 1.2kg$_{f}$ for 2 grains and 0.8kg$_{f}$ for 1 grain respectively. The maximum detachment force of pod is shown as 2.7kg$_{f}$ for 3 grains. grains.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.536-541
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• 2012

An instrumented pod has been developed to measure the aeroacoustic environment as well as the conventional data such as load, vibration, and aerodynamic heating of fighters during flight tests, confirming to the recently developed external pod design for fighters. This study presents the development of the measurement system in detail, being the first indigenous effort in its kind. The pod was designed to meet the requirements of the MIL-HDBK-1763 and MIL-STD-810 Method 515, which are the base to determine the locations and range of sensors. The Endevco 8510B-2 was selected as the sensor to withstand the harsh environment during the flight tests. In order to assess the integrity of the fabricated pod design, a ground run-up test of a KF-16 has been conducted with the pod installed at Station 5. The test results show that the system works well but the sound level exceeds the predetermined sensor range. The sensor range has been readjusted for flight test performed later.

• Mycobiology
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• v.45 no.4
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• pp.392-400
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• 2017

Peanut yield and quality are seriously affected by pod rot pathogens worldwide, especially in China in recent years. The goals of this study are to analyze the structure of fungal communities of peanut pod rot in soil in three peanut cultivars and the correlation of pod rot with environmental variables using 454 pyrosequencing. A total of 46,723 internal transcribed spacer high-quality sequences were obtained and grouped into 1,706 operational taxonomic units at the 97% similarity cut-off level. The coverage, rank abundance, and the Chao 1 and Shannon diversity indices of the operational taxonomic units were analyzed. Members of the phylum Ascomycota were dominant, such as Fusarium, Chaetomium, Alternaria, and Sordariomycetes, followed by Basidiomycota. The results of the heatmap and redundancy analysis revealed significant variation in the composition of the fungal community among the three cultivar samples. The environmental conditions in different peanut cultivars may also influence on the structure of the fungal community. The results of this study suggest that the causal agent of peanut pod rot may be more complex, and cultivars and environmental conditions are both important contributors to the community structure of peanut pod rot fungi.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.1
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• pp.9-22
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• 2022

A fighter performing a reconnaissance mission is equipped with a pod that drives optical/infrared sensors for acquiring and identifying target information on the lower part of the fuselage. Due to the nature of the reconnaissance mission, the fighter performs high speed evasive maneuvers, and the resulting load should be considered importantly for the development of the pod. This paper concerns a numerical investigation into the inertial and aerodynamic loads of the airborne pod of high performance aircrafts. For the aerodynamic load analysis, the pylon and pod shapes are added to the fighter 3D model, and the commercial software was used for static and dynamic analysis. Considering the practical mission conditions, the common/extreme conditions were established respectively in the static and dynamic situations of pods and the driving torque could be tripled under dynamic conditions. In the analysis of inertia load, a 3-DOF model considering roll and turning maneuvers was derived by the Lagrangian method, and then the numerical integration method was applied to the analysis. As a results, it was conformed that the inertia load was generally induced at a low level compared to the aerodynamic load, but depending on the unbalance mass condition of the pod, the inertia load cannot be negligible.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.3
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• pp.301-306
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• 2023

Backgrounds/Aims: Postoperative delirium (POD) is a common complication that increases mortality and morbidity in older patients. This study aimed to evaluate the clinical significance of post-cholecystectomy delirium in older patients. Methods: This retrospective study included 201 patients aged > 75 years who underwent cholecystectomy for acute or chronic cholecystitis between January 2016 and December 2019. Patients were divided into the POD (n = 21) and non-POD (n = 180) groups, and their demographic features and clinical results were compared. Results: The mean patient age was 78.88 years; the female/male ratio was 44.8%/55.2%. Laparoscopic surgery was performed in 93.5% of patients. The univariate analysis showed that lower body mass index (BMI), immobilized admission status, neuropsychiatric disease history, preoperative intervention (percutaneous drainage), high C-reactive protein, hypoalbuminemia, neutrophilia, hypo-/hyperkalemia, and longer operative time were more frequently observed in the POD group. The multivariate analysis showed that lower BMI (odds ratio [OR], 2.796; p = 0.024), neuropsychiatric disease history (OR, 3.019; p = 0.049), hyperkalemia (OR, 5.972; p = 0.007), and longer operative time (OR, 1.011; p = 0.013) were significant risk factors for POD. Conclusions: POD was associated with inflammation degree, general condition, poor nutritional status, electrolyte imbalance, and stressful conditions. Recognizing risk factors requiring multidisciplinary team approaches is important to prevent and treat POD.

• International Journal of Naval Architecture and Ocean Engineering
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• v.2 no.1
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• pp.1-13
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• 2010

A comparative study between a computation and an experiment has been conducted to predict the performance of a Pod type waterjet for cm amphibious wheeled vehicle. The Pod type waterjet has been chosen on the basis of the required specific speed of more than 2500. As the Pod type waterjet is an extreme type of axial flow type waterjet, theoretical as well as experimental works about Pod type waterjets are very rare. The main purpose of the present study is to validate and compare to the experimental results of the Pod type waterjet with the developed CFD in-house code based on the RANS equations. The developed code has been validated by comparing with the experimental results of the well-known turbine problem. The validation also extended to the flush type waterjet where the pressures along the duct surface and also velocities at nozzle area have been compared with experimental results. The Pod type waterjet has been designed and the performance of the designed waterjet system including duct, impeller and stator was analyzed by the previously mentioned m-house CFD Code. The pressure distributions and limiting streamlines on the blade surfaces were computed to confirm the performance of the designed waterjets. In addition, the torque and momentum were computed to find the entire efficiency and these were compared with the model test results. Measurements were taken of the flow rate at the nozzle exit, static pressure at the various sections along the duct and also the nozzle, revolution of the impeller, torque, thrust and towing forces at various advance speed's for the prediction of performance as well as for comparison with the computations. Based on these measurements, the performance was analyzed according to the ITTC96 standard analysis method. The full-scale effective and the delivered power of the wheeled vehicle were estimated for the prediction of the service speed. This paper emphasizes the confirmation of the ITTC96 analysis method and the developed analysis code for the design and analysis of the Pod type waterjet system.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.1
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• pp.19-25
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• 2018

Background: Third molar extraction is associated with considerable pain and discomfort, which is mostly managed with oral analgesic medication. We assessed the analgesic effect of benzydamine hydrochloride, a topical analgesic oral rinse, for controlling postoperative pain following third molar extraction. Methods: A randomized controlled trial was conducted in 40 patients divided into two groups, for extraction of fully erupted third molar. Groups A received benzydamine hydrochloride mouthwash and group B received normal saline gargle with oral ibuprofen and paracetamol. Oral ibuprofen and paracetamol was the rescue analgesic drug in group A. Patients were evaluated on the $3^{rd}$ and $7^{th}$ post-operative days (POD) for pain using the visual analogue score (VAS), trismus, total number of analgesics consumed, and satisfaction level of patients. Results: The VAS in groups A and B on POD3 and POD7 was $4.55{\pm}2.54$ and $3.95{\pm}1.8$, and $1.2{\pm}1.64$ and $0.95{\pm}1.14$, respectively and was statistically insignificant. The number of analgesics consumed in groups A and B on POD3 ($5.25{\pm}2.22$ and $6.05{\pm}2.43$) was not statistically different from that consumed on POD7 ($9.15{\pm}5.93$ and $10.65{\pm}6.46$). The p values for trismus on POD3 and POD7 were 0.609 and 0.490, respectively and those for patient satisfaction level on POD3 and POD7 were 0.283 and 0.217, respectively. Conclusions: Benzydamine hydrochloride oral rinses do not significantly reduce intake of oral analgesics and are inadequate for pain relief following mandibular third molar extraction.