• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.278-280
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• 1996

This paper presents a high performance AC propulsion system for electric car to improve traction capability. The presented VVVF inverter was composed of as GTO thyristor and the the controller was fully digitalized by using 32bit DSP. The improved PWM algorithms and the new adhesion control were adapted to improve traction characteristics. This system could be possible the higher reliability and flexibility. The field test results showed the higher performances characteristics of the presented system.

• The korean journal of orthodontics
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• v.46 no.3
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• pp.155-162
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• 2016

Objective: The aim of this study was to investigate whether labial tooth inclination and alveolar bone loss affect the moment per unit of force ($M_t/F$) in controlled tipping and consequent stresses on the periodontal ligament (PDL). Methods: Three-dimensional models (n = 20) of maxillary central incisors were created with different labial inclinations ($5^{\circ}$, $10^{\circ}$, $15^{\circ}$, and $20^{\circ}$) and different amounts of alveolar bone loss (0, 2, 4, and 6 mm). The $M_t/F$ necessary for controlled tipping ($M_t/F_{cont}$) and the principal stresses on the PDL were calculated for each model separately in a finite element analysis. Results: As labial inclination increased, $M_t/F_{cont}$ and the length of the moment arm decreased. In contrast, increased alveolar bone loss caused increases in $M_t/F_{cont}$ and the length of the moment arm. When $M_t/F$ was near $M_t/F_{cont}$, increases in Mt/F caused compressive stresses to move from a predominantly labial apical region to a palatal apical position, and tensile stresses in the labial area moved from a cervical position to a mid-root position. Although controlled tipping was applied to the incisors, increases in alveolar bone loss and labial tooth inclination caused increases in maximum compressive and tensile stresses at the root apices. Conclusions: Increases in alveolar bone loss and labial tooth inclination caused increases in stresses that might cause root resorption at the root apex, despite the application of controlled tipping to the incisors.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.107-112
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• 2022

This study was conducted to investigate the effects of mulching materials in extensive green roof system by comparing and analyzing the soil moisture content and growth response of Lychnis cognata according to the types of organic mulching materials. The experimental group consisted of a control group that did not use mulching material (Cont.) and a total of five treatment groups, including cocochip (C.O), woodchip (W.O), straw (S.T), and sawdust (S.A), depending on the mulching material. The soil moisture content according to the type of organic mulching material was high in the order of W.O > S.T > Cont. > C.O > S.A, and there was a significant difference especially in S.A. The plant height showed good growth in the order of S.T > Cont. > C.O > W.O > S.A, and there was no significant difference by mulching materials in other growth items except for plant height. Both the chlorophyll and plant water contents were superior to those of untreated group, so the treatment of organic mulching materials is considered to be effective in maintaining the chlorophyll and plant water contents of Lychnis cognata. In particular, the soil moisture content was affected by the characteristics of the mulching material itself. Based on these results, it is required to use a mulching material suitable for the characteristics of each plant in extensive green roof system and it is considered that this can be overcome through organic mulching when selecting a plant species that is weak to water stress.

• Cross-Cultural Studies
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• v.39
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• pp.381-406
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• 2015

Russian nasal consonants / m /, / n / have a feature value not only [+consonant] in common with obstruents, but also [+sonorant] in common with vowels. Nasal / m /(bi-labial) and / n /(dental) have the same place of articulation but different manner of articulation. The feature value of / m / is [+cons, +son, +nas, +ant, -cor, -high, -low, -back, -cont, -del, rel, -strid, +voic], and that of / n / is [+cons, +son, +nas, +ant, +cor, -high, -low, -back, -cont, -del, rel, -strid, + voic]. There is a difference in feature [cor] value of / m / and / n /. In this study it is confirmed that it is a fact that the Russian nasal consonants behave differently from the other consonants in each phonological phenomenon due to their phonological characteristics. The preceding voiced obstruent is changed to an unvoiced one in a process where the last voiceless obstruent in the consonant cluster ' voiced obstruent + nasal /m/ + voiceless obstruent' skips the nasal consonant and spreads its feature value to the preceding voiced obstruent transparently because of the feature [+sonorant] of the nasal consonant. The coronal nasal /n/ participates in a palatalization with the following palatal actively and palatalize preceding plain consonants passively because of markedness hierarchy such as 'Velar > Labial > Coronal'. But the labial nasal /m/ is palatalized with the following velar palatal actively and participates in a palatalization with the following coronal palatal passively. This result helps us confirm the phonological difference of /m/ and /n/ in a palatalization. When the a final consonant is nasal, the unvoicing phenomenon of a final consonant doesn't occur. In such a case as cluster 'obstruent + nasal' the feature value [voiced] of the preceding obstruent doesn't change, but the following nasal can assimilate into the preceding obstruent. When continuing the same nasals / -nn- / in a consonant cluster, the feature value [+cont] of a weak position leads the preceding nasal / n / to be changed into [-cont] / l /. Through the analysis of the frequency of occurrences of consonants in syllabic onsets and codas that should observe the 'Sonority Sequence Principle', the sonority hierarchy of nasal consonants has been confirmed. In a diachronic perspective following nasal / m /, / n / there is a loss of the preceding labial stop and dental stop. But in clusters with the velar stop+nasal, the two-component cluster has been kept phonetically intact.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.663-670
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• 2008

The effect of supplementing the diet of grazing dairy cows with fish oil (FO) and linseed oil (LSO) on milk conjugated linoleic acid (CLA) was investigated. Sixteen Holstein cows (17019 DIM) were assigned into two groups and fed a grain supplement (8.0 kg/d; DM basis) containing 800 g of saturated animal fat (CONT) or 200 g FO and 600 g LSO (FOLSO). All cows grazed together on Sudan grass pasture ad libitum and were fed the treatment diets for 3 wks. Cows were milked twice a day and milk samples were collected during the last three days of the trial. Milk production (24.89 and 22.45 kg/d), milk protein percentage (2.76 and 2.82) and milk protein yield (0.68 and 0.64 kg/d) for the CONT and FOLSO diets, respectively, were not affected (p>0.05) by treatment diets. Milk fat percentage (3.90 and 2.86) and milk fat yield (0.97 and 0.64 kg/d) were lower (p<0.05) with the FOLSO diet compared with the CONT diet. The concentration and yield of milk cis-9 trans-11 CLA were higher (p<0.05) with the FOLSO diet (2.56% of total FA and 16.44 g/d, respectively) than the CONT diet (0.66% of total FA and 6.44 g/d, respectively). The concentrations of milk trans C18:1 and vaccenic acid (VA) were higher (p<0.05) with the FOLSO diet (13.53 and 7.48% of total FA, respectively) than the CONT diet (3.69 and 2.27% of total FA, respectively). In conclusion, supplementing the diet of grazing cows with FO and LSO increased milk cis-9 trans-11 CLA content but reduced milk fat content and yield.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.962-966
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• 2000

Effects of the pattern of energy supply on the efficiency of nitrogen utilization for microbial protein synthesis (MPS) were examined in cows consuming grass silage (7.1 kg DM/d) and supplement of 1 kg sucrose per day given as an intraruminal infusion. Three non-lactating cows received three experimental treatments in a $3{\times}3$ Latin square design with each period lasting 14 days. The treatments were (1) the basal diets of silage alone given in one meal each day at 09:30 h (BASAL), supplemented with (2) 1.0 kg sucrose given a 4-h infusion starting at 09:30 h (SYNC), (3) 1.0 kg sucrose given a continuous infusion for 24 h (CONT). Compared with BASAL, sucrose infusions altered (p<0.05) the pattern of variation in ruminal pH and the concentration of ammonia at 4 h after feeding but none of the sucrose treatments resulted in any changes in the ruminal concentration of VFA. All sucrose treatments increased (p<0.05) MPS relative to BASAL by 14% and 33% for SYNC and CONT, respectively, and that for CONT was greater (p<0.05) than for SYNC. It is concluded that synchronization of energy and nitrogen over the shorter term has no further advantage of the efficiency for MPS relative to CONT.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.4
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• pp.714-721
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• 2007

MAC protocol must be necessarily used because the GPON technology has Point-to-Multipoint structure as connecting an OLT with numerous ONUs. And DBA algorithm must be used to support various services too. There are a few researches in DBA algorithm of GPON, referring the DBA algorithm of BPON which has a waste of bandwidth and the fairness problem between T-CONTs. In this paper, we proposed the BR-DBA algorithm to be able to solve the problems of DBA algorithm on BPON and designed that. As a result of evaluating the performance of BR-DBA algorithm using the NS-2 network simulator, we confirm that the problems of DBA algorithm on BPON were solved and increasing the throughput over BR-DBA algorithm.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.58-68
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• 2015

Requirements to control the large decrease in serum calcium (Ca) due to parturition and to increase the feed intake soon after parturition have been well accepted in dairy cows. This study was aimed to investigate the feed intake affected by serum Ca concentration with difructose anhydride (DFA) III supplement in dairy cows soon after parturition. Fourteen transition Holstein cows were divided into DFA and control (CONT) groups within 1 to 5 parity variations in each group. Measurement schedule for an individual cow was from 14 d before parturition to 7 d following parturition. The cows in DFA group were supplied 0.2 kg/head/d of DFA III feed containing 40 g of pure DFA III while the cows in CONT group received no DFA III. Other feeding procedures were the same for all cows in both groups. At parturition (d 0), serum Ca concentration sharply declined in both groups (p<0.05). Time interval for recovery from decreased serum Ca to its normal range (>9.0 mg/dL) tended to be faster in DFA group (12 h) than in the CONT group (48 h), but the differences were not significant. Active ruminal contraction was observed in DFA group at following parturition of d 1 (p<0.05), d 3 (p<0.05), and d 5 (p<0.01). Dry matter (DM) intake did not differ between the groups. However, positive correlations were observed between serum Ca concentration and ruminal contraction (p<0.001), and between ruminal contraction and DM intake (p<0.001) during following parturition. According to multiple regression analysis ($R^2$ = 0.824, p<0.001), the DM intake was positively affected by serum Ca concentration and ruminal contraction. These results suggest that feed intake soon after parturition in dairy cows can be increased by improvement of serum Ca concentration and active ruminal contraction, but DFA III supplementation in this study did not improve the lower serum Ca concentration due to parturition.

• Research in Community and Public Health Nursing
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• v.23 no.1
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• pp.22-30
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• 2012

Purpose: This study was conducted in order to investigate the effects of an aerobic exercise program on mobility, fall efficacy, balance, and stress in the elderly at senior centers. Methods: This research was conducted as a quasi-experimental pretest and posttest control and experimental comparison study. The subjects were 41 senior residents (Exp.=18, Cont.=23) who aged above 65 at senior centers in S City. The period of time for data collection and intervention was from August 25 to December 5, 2008. Results: Mobility (t=-3.10, p<.01) in the experimental group were significantly higher than those in the control group without an aerobic exercise program. However, fall efficacy (t=1.28, p=.207), balance (t=-.53, p=.602; t=.36, p=.723), stress (t=-1.32, p=.199) in the experimental group was not significantly higher than that in the control group. Conclusion: These findings confirmed that aerobic exercise programs make a contribution to improving mobility in the elderly at senior centers.

• Journal of Korean Biological Nursing Science
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• v.10 no.1
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• pp.25-32
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• 2008

Purpose: This study was carried out to investigate the effect of tourmaline gemstone therapy on relief of dysmenorrhea and menstrual pain of the female university students. Method: A quasi-experimental study was designed. Data were collected from 39 of the Korean female university students (Exp: 26, Cont: 13) from May, 2006 to December, 2006. The collected data were analysed through $x^2$, t-test and Mann-Whitney test. Result: Dysmenorrhea was significantly decreased in the experimental group over that of the control group (p=.001). In addition, menstrual pain was also significantly decreased in the experimental group over that of the control group (p=.000). Conclusion: It was proven that tourmaline gemstone therapy was effective for dysmenorrhea and menstrual pain.