• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.465-468
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• 2003

In order to find out the basic information for salt tolerance in vice (Oryza sativa L.), effects of NaCl treatment on absorption of inorganic components and growth were investigated in 6 japonica and 5 tongil varieties and compared to the salt tolerance variety, Annapurna. The absorption of N and $\textrm{P}_2\textrm{O}_5$ was less repressed than that of $\textrm{K}_2\textrm{O}$, MgO, CaO, and $\textrm{Si}\textrm{O}_2$ which were a little affected by NaCl treatment. $\textrm{K}_2\textrm{O}$ was the most highly repressed component in the absorption of inorganic components, followed by MgO, CaO, total-N, $\textrm{P}_2\textrm{O}_5$ and $\textrm{Si}\textrm{O}_2$. $\textrm{Na}_2\textrm{O}$ content was increased about twenty times to the control at 30days after NaCl treatment, and tonsil varieties more than absorbed japonica ones. Dry weight of japonica varieties by NaCl treatment was less reduced than that of tonsil varieties, followed by Seomjinbyeo, Sinseonchalbyeo, Nakdongbyeo, Daechoungbyeo, Dongjinbyeo and Chuchoungbyeo in japonica group, and Milyang30, Gayeabyeo, Jangseongbyeo, Chilseongbyeo and Taebackbyeo in tonsil group. The relationship between dry weight reduction and Na/K ratio showed positively significant correlation in rice.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.10
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• pp.1275-1282
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• 2012

Helicopter rotor systems are dynamically loaded structures with many composite components such as the main and the tail rotor blades. The fatigue properties of composite materials are extremely important to design durable and reliable helicopter rotor blades. The safe-life methodology has generally been used in the helicopter industry to substantiate dynamically loaded composite components. However, it cannot be used to evaluate the strength reducing effects of flaws and defects that may occur during manufacturing and operational usage. The damage tolerance methodology provides a proper means to overcome this shortcoming; however, it is difficult to economically apply it to every composite component. The flaw tolerant methodology is an equivalent option to the damage tolerance methodology for civil and military rotorcraft. In this study, the flaw tolerant safe-life evaluation is described and illustrated by means of successful application to substantiate the retirement time of composite rotor blades.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.168-173
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• 1991

The uptake of $Mn^{+2}$, a metal cofactor Mn-SOD, by rice seedings resulted in not only a substantial increase in SOD activity in leaf tissues of the plants, but also a significant enhancement of their cold tolerance : the relative extent of the cold tolerance appeared to accord with relative level of the SOD activity. In contrast, $Fe^{+3},\;Cu^{+2}$ and $Zn^{+2}$, which are the cofactors of Fe-SOD and Cu/Zn-SOD, were found to be ineffective for increasing the SOD activity as well as for improving the chilling-resistant capacity of the plants. The results suggest that Mn-SOD, which is most likely induced by its substrate(superoxide) and activated by the presence of $Mn^{+2}$a at high level, is the enzyme acting as an active component of the defense system against low temperature stress in rice plants. In addition, the application of abscisic acid which has been know to protect to some extent certain plants from chilling injury brought about an increase in SOD activity in rice tissues, providing another affirmative information for the crucial role of SOD under the circumstance of cold stress in plants.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.285-290
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• 2001

Purpose : Impaired glucose tolerance (IGT) was standardized in 1979 by the National Diabetes Data Group and the World Health Organization as a risk factor for type 2 diabetes, replacing groups such as 'borderline' and 'chemical' diabetes. The main clinical significance of IGT is as a risk factor for type 2 diabetes and as a risk factor for cardiovascular disease and as a component of the metabolic syndrome. In 1997 the American Diabetes Association(ADA) was proposed the new classification and diagnostic criteria for diabetes, which is strict with the diagnostic baseline of Diabetes from 140mg/dl to 126mg/dl. And it's main purpose is to prevent chronic complications by early diagnosis and treatments. In the oriental medicine, Supungsunkihwan has been used in treatments of Diabetes including IGT & NIDDM, however there is not enough studies about the its objective hypoglycemic effect. so in order to investigate whether there is hypoglycemic effect of Supungsunkihwan, clinical studies were performed with IGT and mild NIDDM patients. Methods : Prior to the study, fasting blood sugar(FBS) and postprandial 2hrs(PP2hrs) glucose were checked. In addition, ECG, cholesterol, TG, HbA1c levels were measured, and the dinical characteristics of patients that can be influence to the blood sugar level such as age, gender, rest type, diet type were surveyed. Supungsukihwan was administered for 7 days, and FBS & PP2hrs were measured again after the therapy. Result : PP2hrs glucose levels were decreased by the administration of Supungsunkihwan. And It's hypoglycemic effects has the correlation with age. That is, the more age increase, the more hypoglycemic effect decrease. Conclusion : Supungsukihwan has hypoglycmic effects on IGT & mild NIDDM patients and it is more effective when administrated to young patients relatively.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.878-888
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• 2018

In the current study, the probiotic potential of approximately 250 strains of lactic acid bacteria (LAB) isolated from piglet fecal samples were investigated; among them Lactobacillus plantarum strain JDFM LP11, which possesses significant probiotic potential, with enhanced acid/bile tolerance, attachment to porcine intestinal epithelial cells (IPEC-J2), and antimicrobial activity. The genetic characteristics of strain JDFM LP11 were explored by performing whole genome sequencing (WGS) using a PacBio system. The circular draft genome have a total length of 3,206,883 bp and a total of 3,021 coding sequences were identified. Phylogenetically, three genes, possibly related to survival and metabolic activity in the porcine host, were identified. These genes encode p60, lichenan permease IIC component, and protein TsgA, which are a putative endopeptidase, a component of the phosphotransferase system (PTS), and a major facilitator in the gut environment, respectively. Our findings suggest that understanding the functional and genetic characteristics of L. plantarum strain JDFM LP11, with its candidate genes for gut health, could provide new opportunities and insights into applications in the animal food and feed additive industries.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.34.4-35
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• 2008

The significant I&T process gain represented by reduction in overall budget expenditure can be obtained from the use of efficient alignment technique for large space optical systems. Such process gain tends to increase rapidly with an increase in aperture and/or in number of optical elements within the system. However, in practice, the alignment of multiple optical components tends to be rather difficult task because of the multiple coupling effects among the elements within the target system. In order to understand and hence identify the complex interplay of the wavefront coupling effects from the alignment process, the original differential wavefront sampling(DWS) method was presented elsewhere in recent years. DWS uses partial differential of the wavefront of optical component and perturbation value of the optical component against a particular alignment factor. The straightforward application of DWS for an off-axis optical system revealed that it tends to give incorrect estimation of the given misalignment state. In this study, we added off-axis correction terms to the original DWS algorithm and investigated its alignment performance. The performance simulation result for a Korsch type space optical system shows that the modified DWS is capable of bringing the misaligned system into the target alignment tolerance only after 3 iterations. It also shows that this new improved algorithm can be used to estimate the source misalignment as well. We are planning to apply this method for the alignment of a 800mm Korsch type telescope in the near future. We discuss the computational technique, simulation results and implications in details.

• Natural Product Sciences
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• v.14 no.4
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• pp.260-264
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• 2008

To find the antidiabetic activity of the tripterpenoid-rich fractions of Rubus coreanus (TRF-cor) and R. crataegifolius (TRF-cra) leaves or its main component niga-ichigoside $F_1$ (Niga-$F_1$), anti-hyperglycemic and antihyperlipidemic effects were investigated in the diabetic rat model induced by streptozotocin (STZ). Treatments of rats with 200 mg/kg of the TRF-cor, TRF-cra (each, p.o.) or 20 mg/kg of Niga-$F_1$ significantly inhibited the increase of blood glucose concentration about 44.8%, 28.7% or 20.6%, respectively, in the diabetic rats. In addition, treatments with those fractions inhibited the increase of serum concentrations of triglyceride, total cholesterol or LDL-cholesterol caused by STZ. The inhibitory rate on atherogenic index (AI) values of the TRFcor (200 mg/kg), TRF-cra (200 mg/kg) or Niga-$F_1$ (20 mg/kg)-treated groups were decreased about 55.7%, 36.3% or 22.6%, respectively, comparable to STZ-treated group. In the oral glucose tolerance test, treatment of TRF-cor or TRF-cra inhibited the increase of blood glucose concentration in the STZ-induced rats. Administration of 20 mg/kg of Niga-$F_1$ (p.o.) also exhibited similar effects with the effects of both TRFs at 200 mg/kg dose (p.o.). These results support that the triterpenoids, in particular Niga-$F_1$, are contributed to the antidiabetic effects of R. coreanus or R. crataegifolius.

• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.621-628
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• 2023

This study derived a reverse engineering procedure for verifying the design identity of original parts and developed parts for PMA(Parts Manufacturer Approval) and STC(Supplemental Type Certificate) of metal brake pads for transport aircraft, which are critical parts among aircraft parts and equipment. In Korea, the regulations for reverse engineering procedures are regulated by the Parts Manufacturer Approval Guidelines, and in the United States, AC No. 21. 303-4. In the reverse engineering for the brake pad, the detailed procedures for each component were determined by selecting verification test items to confirm identity based on sample quantity, dimensional tolerance, mechanical property measurement, material, weight and volume characteristics for each component. In addition, as a result of analyzing the regulation of Korea and United States, in the case of Korea, it is necessary to establish technical standards for braking systems for transport aircraft and regulations related to flight tests.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1231-1234
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• 2003

A sensor working in outdoor may generate some faulty signal owing to dust and high temperature. This paper describes an intelligent sensor system and controller which has a reconstruction mechanism for faulty signal. The faulty signals are dievided into two types as linear distortion and non linear distortion, respectively. The linear distorted signal is due to dust, and non linear distorted signal is due to physical breakdown of sensor or high temperature. These distorted signal have been reconstructed by the proposed method based on polynomial regression method and principal component analysis approach.. The proposed method has been applied to sun tracking system working in outdoor. For a robust and precision control of sun tracker, a fuzzy controller was also proposed. The fuzzy controller controls the tracker by using the collected sensor signal. The tolerance of the position control is within 1.5 degree. To show the validity of the developed system, some experiments in the field were illustrated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2383-2389
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• 2002

This paper describes an experimental study on fatigue life extension by using cold working process in fastener hole of aircraft structure. Cold working process was applied for A12024-7351 specimens by considering the effect of edge margin on fatigue life. It is generally recognized that cold working process offers a protective zone around fastener hole of aluminum aircraft structure due to the residual compressive stresses which lead to retardation of crack growth. Thus this process provides the beneficial effect of increasing the fatigue life of the component. there by decreasing maintenance costs. It has also been successfully incorporated into damage tolerance and structural integrity programs. Cold working specimens were tested at constant amplitude peak cyclic stresses. Fatigue life of cold working specimen compared with that of specimen fabricated with base material. The increase of fatigue life for cold working specimen is discussed by both considering the effect of residual compressive stresses measured by X-ray diffraction technique and quantitative effect of edge margin.