• Korean Journal of Optics and Photonics
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• v.6 no.4
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• pp.379-384
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• 1995

In order to construct B-ISDN, it is inevitable to introduce optical fiber of low loss and wide bandwidth. Coincidently, high count optical fiber cable is solely important to form optical subscriber network. The best structure of high count optical fiber cable to achieve multi-splicing as well as high density at the same time is the one of taking optical ribbon as a unit of accomodation. However, since optical ribbon has its own width. optical loss due to length difference during the bending of ribbon cable unit occurs in relatively easy way. Therefore, care should be taken during its manufacturing and storage. In t\1::; paper, strain, bending radius and lateral pressure of each fiber in ribbon due to the bending of ribbon cable unit are caculated theoretically. Hence, we have measured optical loss of each fiber as function of unit bending radius, when we bent the ribbon cable unit on the various reel. We found that the result accords well with the theoretical analysis. The result shows the importance to determine proper radius of reel used in ribbon cable manufacturing and storage. orage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.201-207
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• 2017

Hay-making is one of the most common forage preservation practices in livestock operations. The objective of hay-making is to minimize nutrient loss by shortening field drying time. Measuring the impacts of cutting height of forage crop is necessary to optimize hay production balancing yield and quality, in order to obtain substantial biomass increase through harvest of regrowth. This experiment was conducted to investigate the impact of cutting height of rye (Secale cereale L.) on drying rate and hay quality. Heading stage rye was harvested at 8cm or 15cm stubble heights. Hay was daily tedded at 09:00 and sampled at 09:00, 13:00 and 17:00 to determine moisture content (MC). After two month of preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter disappearance), TDN (total digestible nutrient), RFV (relative feed value), DM (dry matter) loss, visual scores and total fungi count were determined for estimation of hay quality. Cutting height at 15cm could enhance the drying rate and CP content (p<0.05), but also increases DM loss (p<0.05) compared to cutting at 8cm. Cutting heights did not affect ADF, NDF, IVDMD, TDN and RFV value (p>0.05). Visual scores of rye hays cutting at 8cm and 15cm, ranged from 83 to 85. Cutting at 8cm tended to maintain higher core bale temperature and fungal count than cutting at 15cm during preservation, but there was no significant difference.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.194-196
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• 2004

A 12-year old neutered male Yorkshire terrier dog was presented to the Veterinary Medical Teaching Hospital of Seoul National University with a history of chronic intermittent diarrhea, vomiting, anorexia and weight loss of 2-months duration. On presentation, he was very cachexic and had ascites. Abnormal findings on a complete blood count and chemistry profile included mild anemia, leukocytosis, panhypoproteinemia, hypocholesterolemia, decreased blood urea nitrogen (BUN) and increased serum bile acids. Radiographic findings indicated microhepatica. Peritoneal fluid analysis was consistent with transudates (total protein < 2.5 g/dl, total nucleated cell count = 2,200/ul) and cytologic examination of the fluid revealed neoplastic lymphoblasts. From these findings hepatic dysfunction and protein-losing enteropathy were attributable to abdominal lymphoma. This case suggests that cytologic examination is important in diagnosing underlying diseases of ascites, even if it is transudative effusion.

• Journal of the Korean Statistical Society
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• v.12 no.1
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• pp.1-9
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• 1983

A stress-strength model is formulated for s out of k system of identical components. We consider the estimation of system reliability from survival count data from a Bayesian viewpoint. We assume a quadratic loss and a Dirichlet prior distribution. It is shown that a Bayes sequential procedure can be established. The Bayes estimator is compared with the UMVUE obtained by Bhattacharyya and with an estimator based on Mann-Whitney statistic.

• Tribology and Lubricants
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• v.36 no.6
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• pp.332-341
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• 2020

High-speed turbomachinery implements gas foil bearings (GFBs) due to their distinctive advantages, such as high efficiency, lesser part count, and lower weight. This paper provides the test results of the static structural stiffnesses and loss factors of bump-type foil thrust bearings with increasing preload and bearing deflection. The focus of the current work is to experimentally quantify variability in structural stiffnesses and loss factors among the four test thrust bearings with identical design values and material of the bump and top foil geometries using the same (open-source) fabrication method. A simple test setup, using a rigidly mounted non-rotating shaft and thrust disk, measures the bearing bump deflections with increasing static loads on the test bearing. The inner and outer diameters of the test bearings are 41 mm and 81 mm, respectively. The loss factor, best-representing energy dissipation in the test bearings, is estimated from the area inside the local hysteresis loop of the load versus the bearing deflection curve. The measurements show that structural stiffnesses and loss factors of the test bearings significantly rely on applied preloads and bearing deflections. Local structural stiffnesses of the test bearings increase with applied preloads but decrease with bearing deflections. Changes of loss factors are less sensitive to applied preloads and bearing deflections compared to those of structural stiffnesses. Up to 35% variability in static load structural stiffnesses is found between bearings, while up to 30% variability in loss factors is found between bearings.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.154-157
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• 2001

The effects of pleating parameters on the performance of cylindrical cartridge air filters was experimentally studied. The tested filters are 150 mm in outer diameter and 700 mm in length. As the pleat count increases, the pressure drop across a cartridge filter is decreased for a constant pleat depth and flow rate. This is due to the increased filtration area which brings out less pressure loss of the filter. However, in the case of the filters having the pleat depth of 40 mm, the inner diameter of the cartridges is so small that the pressure loss is greatly increased.

• Journal of Nutrition and Health
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• v.27 no.8
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• pp.844-855
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• 1994

The purpose of this study is to investigate the nutritional status and dietary intake of gastrectomized cancer patients. For this study, from 1993. 1 to 1993. 8, 50 postoperative gastric cancer patients were selected to examine anthropometric and laboratory data(Body Weight, Body Fat, serum Albumin, Total Lympocyte count), and dietary intake related symptoms. The results were 1) All anthropometric and laboratory data were significantly deteriorated by gastrectomy(s-Albumin, TLC. Body Fat : p<0.001). Weight loss of gastrectomized patients was 8.23$\pm$3.72% from admission to discharge. 2) In many gastrectomized cancer patients, preoperative dietary intake was decreased by abdominal discomfort, indigestion, early satiety, and anorexia. 3) Postoperative energy intake was 602$\pm$158㎉, and it is correspond to 31.18$\pm$.90% of daily energy requirement(1918$\pm$236㎉). The cause of poor oral intake is mostly fear, abdominal distension and fullness, and early satiety. In consideration of the fact that an inadequate energy intake was the main cause of the decreasing nutritional status, a careful nutritional care and dietary education is necessry after gastrectomy.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.1
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• pp.33-39
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• 2003

Interior parts of a vehicle are getting important to reduce interior noise. Therefore, prior analysis of cabin noise related with interior parts are necessary at first design stage. Recently, Statistical Energy Analysis(SEA) has been suggested as a possible way for high frequency range noise analysis of interior parts. The validity of noise analysis with SEA to interior parts has been preyed by comparing with experimental result, and the developed method with SEA has been applied in finding optimized interior parts package.

• Journal of Power Electronics
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• v.6 no.3
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• pp.205-213
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• 2006

A cost-effective magnetic-coupled AC-PDP sustain driver with low switching loss is proposed. The transformer reduces current stress in the energy recovery switches which affects circuit cost and reliability. The turns-ratio can be used to adjust the sustain pulse slopes which affect gas discharge uniformity. Dividing the recovery paths prevents abrupt changes in the output capacitance and thereby switching losses of the recovery switches is reduced. In addition, the proposed circuit has a more simple structure because it does not use the recovery path diodes which also afford a large recovery current. By reducing the current stress and device count in the energy recovery circuit, the proposed driver may have decreased circuit cost and improved circuit reliability.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1109-1113
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• 2001

Interior parts of a vehicle are getting important to reduce interior noise of car. Therefore, prior analysis of cabin noise related with interior parts are necessary at first design stage. Recently, Statistical Energy Analysis(SEA) has been suggested as a possible way for meddle of high frequency range analysis with interior parts. This article introduces an example of the application of SEA to predict air born noise of cabin of car.