• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.6
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• pp.135-146
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• 2011

Steel structures have been generally painted to prevent corrosion damage. However, the painted film is deteriorated with increase in service life, and then corrosion damage resulting in cross sectional area occurs on steel surface. As a result, the buckling strength of steel structures can be decreased due to the corrosion damages. The evaluation method of the axial buckling strength of columns about a variety of section shapes and supporting conditions have been presented, but evaluation method of buckling strength about irregular nonprismatic columns is not established. In this study, the axial buckling strength of corroded steels was evaluated based on the buckling test results of corroded steel specimens that were cut off at a temporary steel structure. The corroded specimens were picked up total 10 specimens according to various slenderness ratio from the web of a temporary structure's main beam. The length of specimens is 200, 300, 400, 500 and 600mm respectively. The rust productions were removed by the chemical treatment. Then, the surface geometry was measured at intervals of $1{\times}1mm$ by using the optical 3D digitizing system, and the residual thickness of the specimens was calculated. The axial buckling test was performed on 10 corroded specimens and 12 non-corroded specimens under the fixed-fixed support condition. From the test results, the effect of corrosion damages on axial buckling load was investigated. Regardless of corrosion damage degree, the axial buckling strength of corroded specimens and non-corroded specimens was evaluated identically by using minimum average residual thickness or average residual thickness to minus its standard deviation. Reasonable measuring intervals of residual thickness was proposed by using the results to apply for practical works.

• Journal of Sensor Science and Technology
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• v.6 no.4
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• pp.328-336
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• 1997

The CdSe thin films were grown on the Si(100) wafers by a hot wall epitaxy method (HWE). The source and substrate temperature are $600^{\circ}C$ and $430^{\circ}C$ respectively. The crystalline structure of epilayers was investigated by double crystal X-ray diffraction(DCXD). Hall effect on the sample was measured by the van der Pauw method and studied on the carrier density and mobility dependence on temperature. From Hall data, the mobility was increased in the temperature range 30K to 150K by impurity scattering and decreased in the temperature range 150k to 293k by the lattice scattering. In order to explore the applicability as a photoconductive cell, we measured the sensitivity(${\gamma}$), the ratio of photocurrent to darkcurrent(pc/dc), maximum allowable power dissipation(MAPD), spectral response and response time. The results indicated that the photoconductive characteristic were the best for the samples annealed in Cu vapor compare with in Cd, Se, air and vacuum vapour. Then we obtained the sensitivity of 0.99, the value of pc/dc of $1.39{\times}10^{7}$, the MAPD of 335mW, and the rise and decay time of 10ms and 9.5ms, respectively.

• Economic and Environmental Geology
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• v.44 no.3
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• pp.229-238
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• 2011

S-wave, which provides lithology and pore fluid information, plays a key role in estimating gas-hydrate saturation. In general, P- and S-wave velocities increase in the presence of gas-hydrate and the P-wave velocity decreases in the presence of free gas under the gas-hydrate layer. Whereas there are very small changes, even slightly increases, in the S-wave velocity in the free gas layer because S-wave is not affected by the pore fluid when propagating in the free gas layer. To verify those velocity properties of the BSR (bottom-simulating reflector) depth in the gas-hydrate prospect area in the Ulleung Basin, P- and S-wave velocity profiles were derived from multi-component ocean-bottom seismic data which were acquired by Korea Institute of Geoscience and Mineral Resources (KIGAM) in May 2009. OBS (ocean-bottom seismometer) hydrophone component data were modeled and inverted first through the traveltime inversion method to derive P-wave velocity and depth model of survey area. 2-D multichannel stacked data were incorporated as an initial model. Two horizontal geophone component data, then, were polarization filtered and rotated to make radial component section. Traveltimes of main S-wave events were picked and used for forward modeling incorporating Poisson's ratio. This modeling provides S-wave profiles and Poisson's ratio profiles at every OBS site. The results shows that P-wave velocities in most OBS sites decrease beneath the BSR, whereas S-wave velocities slightly increase. Consequently, Poisson's ratio decreased strongly beneath the BSR indicating the presence of a free gas layer under the BSR.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.773-782
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• 2004

The objective of this work was to establish an approaching method for TMR feeding system in the farm situation by testing the effects of herd-mix feeding system on the performance of lactating cows. Fifty six Holstein cows were fed for the experimental period of 16 months. Prior to test the herd-mix feeding system, animals were kept on conventional feeding system for 4 months, separate feeding of forage with concentrate, then provided 3 types of herd-mix rations formulated by mean level of energy concentration requirement of higher 1/2 ranker in each herd for remaining 12 months to compare the effect on milk yield performance of animals with conventional feeding system by using a switch-over method. The herd-mix feeding system influenced substantially upon the improvements of milk yield(P<0.01) and milk fat percentage(P<0.05). In all of lactational ages, milk yield and milk fat were enhanced by the herd-mix feeding system. Especially, actual milk yield(AMY) and milk fat in the 1st lactating cows, and AMY and 4.0% fat corrected milk yield(FCM) in the 2nd lactating cows were increased signiticantly by the herd-mix feeding system(P<0.05). In the early and mid-stage of lactation, the herd-mix feeding system showed higher AMY and FCM compared with the conventional feeding system although the milk fat was not different. AMY, milk fat and FCM in the late-stage of lactation were increased generally by the herd-mix feeding system. Especially, milk fat and FCM obtained by the herd-mix feeding system were significantly higher than those by the conventional feeding system(P<0.01). The herd-mix feeding system showed a good type of milking curve with a higher persistency of FCM(93.24%) than in conventional one(92.69%). The income over feed cost with the herd-mix feeding system was lA-fold higher than that with the conventional feeding method. In conclusion, the results of this work suggest that the herd-mix feeding system based on a correct level of energy concentration of TMR and well-determined feed ingredients increases not only milk yield of dairy herd by enhancing the performance of cows in early to mid stage of lactation with improved milk persistency but also gross income of dairy farm.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.491-500
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• 2007

Two experiments were used to determine the effects of environment-friendly diets on growth performance, fecal excretion, nitrogen excretion and emission gases in manure for growing pigs. In experiment 1, ninety six crossed pigs(Landrace×Yorkshire×Duroc) were allocated into four treatments. Treatments were AME(adequate ME diet, 3,265 kcal/kg), LME(lower ME diet, 3,100 kcal/kg), LME 0.05(lower ME diet+α- galactosidase & β-mannanase 0.05%) and LME 0.10(lower ME diet+α-galactosidase & β-mannanase 0.10%). Pigs fed AME diet had lower ADFI(Average Daily Feed Intake) than pigs fed other diets(p<0.05). DM(Dry Matter) digestibility in pigs fed AME and LME 0.10 diets had greater than pigs fed LME diet(p<0.05). Energy digestibility is higher in pigs fed AME and LME 0.10 diets than other treatments(p<0.05). In experiment 2, twenty four crossbred pigs(33.71 kg average BW) were used in a 14-d metabolism experiment. The pigs were housed in individual cages equipped with plastic bed flooring. Treatments were CP(Crude protein) 18% without Bacillus sp., CP 18% diet+Bacillus sp. 0.05%, CP 14% without Bacillus sp. and CP 14% diet+Bacillus sp. 0.05%. Nitrogen intake was higher for CP 18% diets than CP 14% diets(p<0.05). DM, N(Nitrogen) and energy digestibility were affected by probiotics(p<0.05). With the high CP in diets, Energy and N digestibility, urine N percent, urine N excretion and total N excretion were increased significantly compared to low CP in diets(p<0.05). Among the treatments, DM and N digestibilities, feces N excretion, N absorption were decreased significantly(p<0.05), however, feces excretion, feces N, urine N percent, urine N excretion and total N excretion were increased significantly(p<0.05) when pigs fed without probiotics diets compare to pigs fed with probiotics diets. DM and N digestibility, feces excretion, feces N excretion, urine N percent, urine N excretion, total N excretion, N absorption and N adsorption ratio were CP×probiotic interactions in p<0.05. Ammonia(p<0.01) and H2S(p<0.05) in manure were lower in CP 14% diets than CP 18% diets. Also, ammonia and H2S in manure were CP×probiotic interactions in p<0.05. In conclusion, low energy and reduction of CP dietary added enzyme and probiotics improved nutrient digestibility and reduced odors emission in manure for growing pigs.

• The Korean Journal of Pharmacology
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• v.20 no.2
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• pp.15-21
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• 1984

It was aimed to study the effects of ${\alpha}_2-adrenoceptor$ agonists on the sleeping time in $one{\sim}two-day-old$ chickens. Furthermore, it was also evaluated whether ${\alpha}_1-adrenoceptor$ agonist and antagonist might affect the sleeping in the chickens and discussed in relation with opiate receptor. 1) Guanabenz, clonidine, guanfacine and B-HT 933 decreased the latency of the loss of righting reflex in a dose-dependent manner, but B-HT 920 and oxymetazoline slightly prolonged it. 2) ${\alpha}_2-Adrenoceptor$ agonists produced dose·related increase in sleeping time. The potency was guanabenz>clonidine>oxymetazoline${\geq}$B-HT 933${\geq}$B-HT 920>guanfacine in this order. 3) ${\alpha}_2-Adrenoceptor$ antagonists decreased guanabenz-induced sleeping time in a dose ·dependent manner. The rank order of ${\alpha}_2-adrenoceptor$ antagonists was yohimbine>rauwolscine>piperoxan${\geq}$RX 781094. 4) Sleeping time caused by both ethanol and hexobarbital was not affected by yohimbine in chickens. 5) Methoxamine and phenylephrine showed little significant effect on the guanabenz-induced sleeping time. However, prazosin increased it. Paradoxically, corynanthine rather caused to decrease it. These results suggest that the stimulation of central ${\alpha}_2-adrenoceptor$ mediates sleeping, however it is remained uncertain in the role of central ${\alpha}_1-adrenoceptor$ in chickens. In addition, the one~two-day-old chickens may be considered as a useful, inexpensive and simple experimental model to evaluate the in vivo pharmacological action of the ${\alpha}_2-adrenoceptor$ agonist and antagonist related to sedation.

• The Journal of Korean Society for Radiation Therapy
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• v.29 no.1
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• pp.27-35
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• 2017

Purpose: On the left side, breast cancer patients have more side effects than those on the right side because of unnecessary doses in normal organs such as heart and lung. DIBH is performed to reduce this. To evaluate the dose of peripheral organs in the left breast cancer including supraclavicular lymph nodes and internal mammary lymph nodes according to the treatment planning method of Conventional Radiation Therapy, Intensity Modulated Radiation Therapy and Volumetric Modulated Arc Therapy. Materials and Methods: We performed CT-simulation using free breathing and deep inspiration breath-hold technique for 8 patients including left supraclavicular lymph nodes and internal mammary lymph nodes. Based on the acquired CT images, the contour of the body is drawn and the convention is performed so that $95%{\leftarrow}PTV$, $Dmax{\leftarrow}110%$. Conventional Radiation Therapy used a one portal technique on the supraclavicular lymph node and used a field in field technique tangential beam on the breast. Intensity Modulated Radiation Therapy was composed of 7 static fields. Volumetric Modulated Arc Therapy was planned using 2 ARC with a turning radius of $290^{\circ}$ to $179^{\circ}$. The peripheral normal organs dose was analyzed by referring to the dose volume of Eclipse. Results: By applying the deep inspiration breath-hold technique, the mean interval between the heart and chest wall increased $1.6{\pm}0.6cm$. The mean dose of lung was $19.2{\pm}1.0Gy$, which was the smallest value in Intensity Modulated Radiation Therapy. The V30 (%) of the heart was $2.0{\pm}1.9$, which was the smallest value in Intensity Modulated Radiation Therapy. In the left anterior descending coronary artery, the dose was $25.4{\pm}5.4Gy$, which was the smallest in Intensity Modulated Radiation Therapy. The maximum dose value of the Right breast was $29.7{\pm}4.3Gy$ at Intensity Modulated Radiation Therapy. Conclusion: When comparing the values of surrounding normal organs, Intensity Modulated Radiation Therapy and Volumetric Modulated Arc Therapy were applicable values for treatment. Among them, Intensity Modulated Radiation Therapy is considered to be a suitable treatment planning method.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.3
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• pp.82-93
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• 2008

In order to ensure a standardized data analysis of the eddy covariance measurements, Hong and Kim's quality control program has been updated and used to process eddy covariance data measured at two levels on the main flux tower at Gwangneung site from January to May in 2005. The updated program was allowed to remove outliers automatically for $CO_2$ and latent heat fluxes. The flag system consists of four quality groups(G, D, B and M). During the study period, the missing data were about 25% of the total records. About 60% of the good quality data were obtained after the quality control. The number of record in G group was larger at 40m than at 20m. It is due that the level of 20m was within the roughness sublayer where the presence of the canopy influences directly on the character of the turbulence. About 60% of the bad data were due to low wind speed. Energy balance closure at this site was about 40% during the study period. Large imbalance is attributed partly to the combined effects of the neglected heat storage terms, inaccuracy of ground heat flux and advection due to local wind system near the surface. The analysis of wind direction indicates that the frequent occurrence of positive momentum flux was closely associated with mountain valley wind system at this site. The negative $CO_2$ flux at night was examined in terms of averaging time. The results show that when averaging time is larger than 10min, the magnitude of calculated $CO_2$ fluxes increases rapidly, suggesting that the 30min $CO_2$ flux is influenced severely by the mesoscale motion or nonstationarity. A proper choice of averaging time needs to be considered to get accurate turbulent fluxes during nighttime.

• Journal of Intelligence and Information Systems
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• v.21 no.3
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• pp.53-77
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• 2015

Korea has witnessed an increasing number of domestic patent applications, but a majority of them are not utilized to their maximum potential but end up becoming obsolete. According to the 2012 National Congress' Inspection of Administration, about 73% of patents possessed by universities and public-funded research institutions failed to lead to creating social values, but remain latent. One of the main problem of this issue is that patent creators such as individual researcher, university, or research institution lack abilities to commercialize their patents into viable businesses with those enterprises that are in need of them. Also, for enterprises side, it is hard to find the appropriate patents by searching keywords on all such occasions. This system proposes a patent recommendation system that can identify and recommend intellectual rights appropriate to users' interested fields among a rapidly accumulating number of patent assets in a more easy and efficient manner. The proposed system extracts core contents and technology sectors from the existing pool of patents, and combines it with secondary social knowledge, which derives from tags information created by users, in order to find the best patents recommended for users. That is to say, in an early stage where there is no accumulated tag information, the recommendation is done by utilizing content characteristics, which are identified through an analysis of key words contained in such parameters as 'Title of Invention' and 'Claim' among the various patent attributes. In order to do this, the suggested system extracts only nouns from patents and assigns a weight to each noun according to the importance of it in all patents by performing TF-IDF analysis. After that, it finds patents which have similar weights with preferred patents by a user. In this paper, this similarity is called a "Domain Similarity". Next, the suggested system extract technology sector's characteristics from patent document by analyzing the international technology classification code (International Patent Classification, IPC). Every patents have more than one IPC, and each user can attach more than one tag to the patents they like. Thus, each user has a set of IPC codes included in tagged patents. The suggested system manages this IPC set to analyze technology preference of each user and find the well-fitted patents for them. In order to do this, the suggeted system calcuates a 'Technology_Similarity' between a set of IPC codes and IPC codes contained in all other patents. After that, when the tag information of multiple users are accumulated, the system expands the recommendations in consideration of other users' social tag information relating to the patent that is tagged by a concerned user. The similarity between tag information of perferred 'patents by user and other patents are called a 'Social Simialrity' in this paper. Lastly, a 'Total Similarity' are calculated by adding these three differenent similarites and patents having the highest 'Total Similarity' are recommended to each user. The suggested system are applied to a total of 1,638 korean patents obtained from the Korea Industrial Property Rights Information Service (KIPRIS) run by the Korea Intellectual Property Office. However, since this original dataset does not include tag information, we create virtual tag information and utilized this to construct the semi-virtual dataset. The proposed recommendation algorithm was implemented with JAVA, a computer programming language, and a prototype graphic user interface was also designed for this study. As the proposed system did not have dependent variables and uses virtual data, it is impossible to verify the recommendation system with a statistical method. Therefore, the study uses a scenario test method to verify the operational feasibility and recommendation effectiveness of the system. The results of this study are expected to improve the possibility of matching promising patents with the best suitable businesses. It is assumed that users' experiential knowledge can be accumulated, managed, and utilized in the As-Is patent system, which currently only manages standardized patent information.

• Restorative Dentistry and Endodontics
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• v.34 no.3
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• pp.169-176
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• 2009

Diabetes Mellitus (DM) is a syndrome accompanied with the abnormal secretion or function of insulin, a hormone that plays a vital role in controlling the blood glucose level (BGL). Type land 2 DM are most common form and the prevalence of the latter is recently increasing, The aim of this article was to assess whet her Type 2 DM could act as a predisposing risk factor on the pulpo-periapical pathogenesis. Previous literature on the pathologic changes of blood vessels in DM was thoroughly reviewed. Furthermore, a histopathologic analysis of artificially-induced periapical specimens obtained from Type 2 diabetic and DM-resistant rats was compared. Histopathologic results demonstrate that the size of periapical bone destruction w as larger and the degree of pulpal inflammation was more severe in diabetic rats, indicating that Type 2 D M itself can be a predisposing risk factor that makes the host more susceptible to pulpal infection. The possible reasons may be that in diabetic state the lumen of pulpal blood vessels are thickened by atheromatous deposits, and microcirculation is hindered, The function of polymorphonuclear leukocyte is also impair ed and the migration of immune cells is blocked, leading to increased chance of pulpal infection. Also, lack of collateral circulation of pulpal blood vessels makes the pulp more susceptible to infection. These decrease the regeneration capacity of pulpal cells or tissues, delaying the healing process, Therefore, when restorative treatment is needed in Type 2 DM patients, dentists should minimize irritation to the pulpal tissue un der control of BGL.