• International Journal of Automotive Technology
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• v.7 no.1
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• pp.9-15
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• 2006

Prediction of the performance of a carbon canister in vehicle evaporative emission control system has become an important aspect of overall fuel system development and design. A vehicle's evaporative emission control system is continuously working, even when the vehicle is not running, due to generation of vapors from the fuel tank during ambient temperature variations. Evaporative emissions from gasoline powered vehicles continue to be a major concern. The objective of this paper is to clarity the flow characteristics and other such fundamental data for the canister during loading and purging are needed, and this data will prove valuable in the development of the canister. This paper is to evaluate the relationship between carbon canister condition and engine performance during engine operation, and the effects of evaporative emissions on the engine performance were investigated.

• Journal of the Korean Institute of Gas
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• v.2 no.4
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• pp.25-33
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• 1998

The characteristics of evaporation heat transfer for the utilization of LNG cold energy was investigated experimentally using liquified nitrogen and a solution of ethylene-glycol and water under horizontal two-phase conditions in the small-scale equipment of a cryogenic heat exchange system. The inner tubes in the double pipe heat exchanger with 8 mm and 15 mm inner diameter and 6 m length were adopted as a smooth test tubes and enhanced tubes by means of wire-coil inserts. Heat transfer coefficients and Nusselt number for the test tube were calculated from measurements of temperatures, flowrates and pressures. The correlations in a power-law relationship of the Nusselt number, the Reynolds number and Prandtl number for heat transfer were proposed which can be available for design of cryogenic heat exchangers. The correlations showed heat transfer coefficients for the wire-coil inserts were much higher than those for the smooth tubes, increased by more than 2.5 ${\~}$ 5.5 times depending upon the equivalent Reynolds number. Form and length of cryogenic double pipe heat exchanger were proposed for applicable to the utilization of LNG cold energy.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.179-188
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• 1994

This study was conducted to investigate the distribution of potassium fractions and to establish the soil chemical indices for assessing potassium availability in upland soil. Soil samples were collected from 66 vegetable crop fields of Chungbuk Jungweon, Jeonbuk Imsil and Kyengbuk Euiseong and these samples were analyzed water soluble(W. S. -K), exchangeable(Exch. -K) and nonexchangeable potassium(Nonex. -K). The distribution of potassium fractions was examined for soils having different physico-chemical properties and compared with the soil parameters related to the potassium availability. 1. The distribution ranges of W.S.-K, Exch.-K and Nonex.-K were 0.07~1.42, 0.27~2.30, and 0.84~4.74me/100g, and average contents of relevent fractions were 0.40, 1.03 and 2.37me/100g respectively. 2. Contents of W.S.-K and Exch.-K were decreased with increasing soil pH, CEC, Exch. Ca and Exch. Mg contents but Nonex. -K showed a low correlationship with these factors. 3. Exch.-K content slightly inereased with increasing clay content, while W.S.-K and Nonex. -K contents were grandually decreased with clay contents. 4. The relationship between W.S.-K and Exch.-K was significant and W.S.-K was released from soil at 0.23me/100g content of Exch.-K 5. Contents of W.S-K and Exch.-K showed high correlationship with soil chemical parameters such as ratio of exchangeable cations(K/Ca+Mg), ratio of exchangeable cation equivalent[$K/{\sqrt{Ca+Mg}}:(me/100g)^{1/2}$], potassium exchangeable free energy(${\Delta}F=RT$ 1n $K/{\sqrt{Ca+Mg}}$ : calories/mole) and saturation percentage of potassium($Exch.K/CEC{\times}100$), and these factors were considered to be good parameters for assessing soil potassium availability.

• Journal of Biosystems Engineering
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• v.19 no.1
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• pp.22-32
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• 1994

The combine harvester is considered as an important but complicated and costly machine. The appropriate size of combine has to be developed to use efficiently in Korea. But the combine is such a complicated machine that a complete design model to develop a new type is impossible without understanding the relationship between each factor. The combine capacity is generally limited by the cleaning shoe performance. So a design model for a cleaning shoe has to be developed first for the complete combine design. The objective of this research was to develop a cleaning model of head-feeding combine to predict grain separation from chaff and broken straw on a sieve. A developed physically based model can explain the situation which can happen during separation process. A test apparatus based on the field going machine was developed. The test materials were paddy rice and barley. The data obtained were analyzed by the hand and the video camera. The developed model was verified as an adequate model through the test with $R^2$ of 0.934 and 0.837. The model can be used to evaluate design and operation alternatives of combine and also applied to the automatic control of separation unit of combine with a loss monitering sensors.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.2
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• pp.131-135
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• 1993

The ultrasonographic examination with vaginal probe(5MHz) was undertaken in 101 patients at infertility clinic of Eul-Ji General Hospital. This study was performed to evaluate the number of mature follicles per menstrual cycle, the relationship of both ovaries for consecutive ovulatory cycle and the responsiveness of follicular growth followed by administration of ovulation inductant. The results were as follows; 1. The ovulation induction group with clomiphene citrate showed more follicles than natural menstrual cycle group. 2. Each means of numbers of follicles between ovaries showed no difference between natural and ovulatory induction groups. 3. The rate of follicular growth per one menstrual cycle showed higher in the clomiphene citrate induced cycle group. 4. Clomiphene citrate induced group tends to be easier for multiple follicular growth but had no significant difference in statistics. 5. The ipsilateral Vs. contralateral follicular growth rate for consecutive menstrual cycles in both ovaries showed no significant difference between two groups.

• Transactions of Materials Processing
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• v.22 no.7
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• pp.401-406
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• 2013

The use of roll-formed products increases every year due to its advantages, such as high production rates, reduced tooling cost and improved quality. However, till now, it is limited to part profiles with constant cross section. In recent years, the flexible roll forming process, which allows variable cross sections of profiles by adaptive roll stands, was developed. In this study, an attempt to optimize profile design for the flexible roll forming process was performed. An equation that predicts the longitudinal strain for part geometries with variable cross-sections was proposed. The relationship between geometrical parameters and the longitudinal strain was analyzed and investigations on the optimal profile design were performed. Experiments were conducted with a lab-scale roll forming machine to validate the proposed equation. The results show that the profile design method proposed in this study is feasible and parts with variable cross sections can be successfully fabricated with the flexible roll forming process.

• Proceedings of the KIEE Conference
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• 2004.05b
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• pp.132-135
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• 2004

In generally, compared with VHF band, electromagnetic waves of UHF band have a low influence for external noise. We can detect the real abnormality with several pC in GIS using UHF method. Recently, it has applied to use the external UHF sensor attached on spacer to GIS of existing substation. In this paper, we firstly described the technique of the partial discharge measurement using frequency analysis and phase analysis in UHF band. Secondly, we presented the results of sensitivity, the relationship of dBm-pC and diagnosis of the reason of PD source by phase analysis. And then, we report the diagnosis result of partial discharge on 800kV GIS in domestic substation. rge diagnosis of GIS.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.1-10
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• 2005

Intramuscular fat content(lMF) is considered as one of major economic traits in the pig breeding and industry. In general, high IMF results in better meat quality. Several approaches to detect quantitative trait 10ci( QTL) for IMF indicated a strong possibility of the existence of a QTL related to IMF between the microsatellite marker SW71 and SW1881 on SSC6q. Porcine FABP3 has been considered as a candidate gene affecting IMF due to its physiological roles and position on the pig genome. Two novel mutations, g.-114T> C and g.-158T>G were detected by duplicate sequencing of the porcine FABP3 promoter region. These two mutations were identified as absolute linkage disequilibrium. The g.-158T> G mutation was used for investigating relationships with growth and fat deposition traits. The GG genotype of the g.-158T> G polymorphism showed highly negative effects(P< 0.01) on body weights at 3 and 12 weeks of age, and a positive effect(P< 0.05) on IMF. However, backfat thickness(BF) and carcass fat(CF) content were not significantly associated with the genotype. The result indicates that the novel mutations, identified in this study, could be utilized as possible genetic markers to improve IMF, independent with BF.

• Journal of Aquaculture
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• v.15 no.2
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• pp.111-117
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• 2002

Effect of substrate composition, stocking density and food organisms on survival and growth of the surf clam, Spisula sachalinensis was studied. Spat collection from the substratum was the highest, when its sand size was less than 250 $\mu m4; at such substratum, survival and growth of the surf clam were also the highest. The spat (1.4 mm) grew to 4.6 mm and 8.2 mm in shell length on day 30 and 50, respectively. The relationship between shell length (SL) and shell height (SH), shell breadth (SB), total weight (TW) and shell weight (SW) of the spat are formulated by the following equations; SH : 0.7351SL+0.2272 ( $r^2$ =0.9600)i SB = 0.4037SL+0.2112 ($r^2$ = 0.9452); TW : 0.2824SL^{2.7020} ($r^2$ = 0.9820)i SW = $0.4021SL^{2.0217} ($r^2$ : 0.6169). In the substratum containing fine sand, growth and survival of the clam roared at the density of 1~2 ind./$cm^2$ were optimal. The quality of feed decreases in the following order; C. calcitrans, mixture group, I. galbana, P. lutheri, T. suecica.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.90-95
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• 1981

This study was conducted to ascertain the seed quality of sesame (Sesamum indicum L.) under different environmental conditions. The results were summarized as follows; 1. The sesame seeds harvested in the central noethern area of Korea showed higher linoleic acid content than did those in the southern area. 2. The linoleic acid content was highly negatively correlated with the accumulated temperature during maturity (r=-.595) and the correlation coefficient between Linoleic acid content and the accumulated solar radiation during maturity was highly significant (r=.613). Thus, the relative low temperature and high solar radiation during the maturity would be importnat factors for the increase in the linoleic acid content of sesame seeds. 3. The oleic acid content was higher in the southern area than in the central northern area. 4. The oleic acid content was highly correlated with the accumulated temperature (r=.644) and the accumulated solar radiation (r=-.456), respectively. 5. The linoleic and oleic acid are important components of sesame seeds, and these show a relative relationship to determine the oil content of the seeds. 6. The oil quality in the central northern area was superior to that in the southern area.