• 한국해양학회지
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• v.11 no.1
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• pp.1-8
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• 1976

This work concerns ecological studies on the larvae of the ark shell, Anadara broughtonii(SCHRENCK), in the aea adjacent to Gajyo-do in Jinhae Bay. Marine environmental factors, namely, temperatue, salinity, depth, and tidal current were observed in connection with the larval distributions. Water temperature appeared to be one of the main factors that influence the spawning activity. The numbers of the drifting larvae fluctuated greatly during the study period. The trend, however, was for numbers to be low in early summern, increasing in mid summer, and reaching a peak in late summer, at high bottom water temperature and low bottom salinities. Significantly increased numbers of the drifting larvae were observed during the period in which the bottom water temperatures and salinities were very close to those at the surface. the numbers of the drifting larvae showed a positive relationship with velocities of the water mass within the range of 0∼20 cm/sec. It was also noticed that the drifting larvae were relatively abundant in the area of eddy motion.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.2
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• pp.118-123
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• 2011

This study aims to investigate stereotype and effective cue presentation methods for burner-control relationship of four-stove range for Korean. A total of 381 subjects(male : 262, female : 119) were surveyed using questionnaire, in which eight gas range models drawn by 3-D Max 2010 were presented. The gas range models were labeled by signs(☆#${\triangle}{\square}$) to eliminate suggestive effect of sequential codes such as alphabets and numbers. The results showed that the stereotype was significantly affected by occupation(p < 0.10), but not by subjects' gender and age(p > 0.39). The stereotype of four-burner gas range for Korean was the same as that of Chinese, while the stereotype was different from that of American. The cues with rectangular-shaped arrangements identical or similar to those of burners were effective to relate burners to corresponding controls. The diamond-shaped cues and burner arrangements were not appropriate for representing burner-control relationship of four-stove gas range. These findings would be used as a basic guideline when designing four-burner gas range or similar equipments.

• Speech Sciences
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• v.9 no.3
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• pp.3-16
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• 2002

We examined some problems in speaker identification procedures: transformation of acoustic parameters into auditory scales, invalid measurement values, and comparability of spectral energy values across the frequency range. To resolve those problems, we analyzed the acoustic spectral energy of three Korean numbers produced by ten female students from narrow-band spectrograms at 19 proportional time points of each voiced segment. Then, cells of the first five spectral matrices were averaged to form a matrix model for each speaker. The correlation coefficients and sum of the absolute amplitude difference in each pair of the spectral models of the ten subjects were obtained. Also, some individual matrix models were compared to those of the same subject or the other subject with a similar spectral model. Results showed that in numbers '2' and '9' subjects could not be clearly distinguished from the others but in number '4' it shed some possibility of setting threshold values for speaker identification if we employed the coefficients and the sum of absolute difference. Further studies would be desirable on various combinations of the range of long-term average spectra and the degree of signal pre-emphasis.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.11
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• pp.767-774
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• 2008

This paper presented the heat transfer and pressure drop characteristics for micro plate heat exchanger with straight channel. The metal sheets for straight channel are manufactured by chemical etching and fabricated micro plate heat exchangers by using the vacuum brazing of bonding technology. The performance experiments are performed within the Reynolds numbers range of 15$\sim$250 under the same flow rate conditions for hot and cold sides. The inlet temperature of hot and cold water are conducted in the range of $30^{\circ}C{\sim}50^{\circ}C$ and $15^{\circ}C{\sim}25^{\circ}C$, respectively. Heat transfer rate and pressure drop are evaluated by the Reynolds numbers and mass flow rates as the inlet temperature variations of the hot and cold sides. Correlations of Nusselt number and friction factor are suggested for micro plate heat exchanger with straight channel using the results of performance experiment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.281-285
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• 1976

An investigation on the breeding time of the Mangrove oyster, Crassostrea rhizaphorae, in the lagoon of Cocineta which is located in the northwestern part of Venezuela was carried out from February through May in 1976. Surface water temperature was high, over $25^{\circ}C$ and specific gravity was around 1.0258. Transparency to water depth varied between 29 and $80\%$. The range of water content of the oysters increased from February through May. However, the averge monthly range of water content varied only slightly from 80.67 to $82.25\%$. From the numbers of matured planktonic larvae together with total numbers of planktonic larvae found, we may assume that the best seedling period is from late April through early May. We may also assume that the best area is around stations 4 and 3, station 3 being slightly better than station 4.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.5 s.176
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• pp.1314-1322
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• 2000

The acoustic property of reactive type single expansion chamber can be analyzed by traditional plane wave theory. This theory can be applied in low frequency range and has good performance. But this theory can't include higher order modes, therefore another method is essential to analyze acoustic filter in high frequency range. Many researcher suggested the method that can concern higher order modes, and their methods are using mode matching technique. But there is no method that can be applied to the analysis of single expansion chamber with arbitrary inlet/outlet duct position and numbers of higher order modes of inlet/outlet duct and middle chamber. In this paper, the method which can analyze single expansion chamber with arbitrary inlet/outlet duct position and numbers of higher order modes of inlet/outlet duct and middle chamber using fundamental mode matching technique, was suggested and the predictions by this method was compared with those by the finite element method, and the influence of inlet/outlet location to acoustic performance of single expansion chamber is investigated and explained by higher order mode effects.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.6
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• pp.435-442
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• 2009

Three-dimensional heat transfer characteristics for natural convection flows are numerically investigated in the doubly-inclined cubical-cavity according to the variation of a newly defined orientation angle �� of the hot wall surface from horizontal plane at moderate Rayleigh numbers. Numerical simulations of laminar flows are conducted in the range of Rayleigh numbers($10^4{\leq}Ra{\leq}10^5$) and $0^{\circ}{\leq}{\alpha}90^{circ}$ with a solution code(PowerCFD) employing unstructured cell-centered method. Comparisons of the average Nusselt number at the cold face are made with benchmark solutions and experimental results found in the literature. It is found that the average Nusselt number at the cold wall has a maximum value around the specified orientation ${\alpha}$ at each Rayleigh number. Special attention is also paid to three-dimensional thermal characteristics in natural convection according to new orientation angles at Ra��= $1{\times}10^5$, in order to investigate a new additional heat transfer characteristic found in the range of above Ra = $6{\times}10^4$.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.3
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• pp.65-72
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• 2015

In present study, a supersonic inlet for dual mode ramjets or RBCC/TBCC engines with a wide range of flight Mach numbers is designed. A conical variable inlet configuration is chosen for the inlet design. Geometric relations with angles of compression cones and conical shock waves are used for the design of the inlet configuration. The performance of the supersonic inlet is confirmed by the numerical analysis. The capture area ratio is maintained around 100% from Mach 3 to 8 conditions.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.363-368
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• 2007

Traditional kochujang samples were collected from the folk village in Sunchang to find the major microbial composition and correlation between the taste and the microbial properties. Among the 29 samples, 17 samples showed Bacillus licheniformis as dominant strain with 11 samples Bacillus subtilis and 1 sample Staphylococcus pasteuri. Subdominant strain of 17 samples was Bacillus licheniformis with 12 samples Bacillus subtilis. Dominant strain numbers varied in rage of $6.60{\sim}8.38$ logCFU/g with subdominant strain number $5.90{\sim}7.86$ logCFU/g and total microbial number $6.64{\sim}8.56$ logCFU/g respectively. Bacterial type number varied in range of $6{\sim}18$ with the average 10.5 types. Fungi were found only in 2 samples and identified all to be Aspergillus oryzae. Yeasts were found in 25 samples. The dominant yeast strain of 23 samples was identified to be Zygosaccharomyces pseudorouxii and that of 2 samples Zygosaccharomyces rouxii. Yeast type variety showed that only single type was found in 15 samples, 2 types in 8 samples, 3 types in 1 sample and 4 types in 1 sample. Fungal number was 3.90 and 4.08 logCFU/g and yeast numbers varied in range of $3.90{\sim}6.43$ logCFU/g. The sensory scores of kochujang showed positive correlation with type numbers, but no significant correlation with the other microbial properties like total bacterial number, dominant bacterial number, subdominant bacterial number and dominant yeast number.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.53-58
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• 2009

The propose of this study was to find out optimum conditions for no-tillage rice-winter cover crops cropping system. A field research was conducted to evaluate productivity and quality of rice cultivars (Dongjinbyeo and Junambybyeo) in rice-winter cover cropping systems at Doo-ryangmyeon., Sacheon, Gyeongsangnam-do, Korea from January 2005 to October 2006. The experimental soil was Juggog series (fine silty, mesic family of Fluvaquentic Eutrndepts). The rice cultivars were experimented under some different high residue farming systems, i.e. no-tillage no treatment (NTNT), no-tillage amended with rice straw (NTRS), no-tillage amended with rye (NTR), no-tillage amended with Chinese milkvetch (NTCMV), tillage no treatment (TNT), and conventional cropping system (Control). The miss-planted rate was 8.8% in 2005 and range of 10.8% to 13.3% in 2006 at NTR, and the other treatments were carried out at miss-planted rate ranging from 1.2% to 5.0%. Tiller numbers of Junambyeo, and Dongjinbyeo in both of years were the highest in Control, and decreased nearly in NTCMV, NTR, NTRS, NTNT, and TNT in that order. The lowest grain yield was observed in TNT both cultivars due to the lower tiller numbers per area, and spikelet numbers per panicle. Also, no-tillage treatments were lower grain yield than control. On the other hand, 1,000-grain weight was lowest in control due to higher tiller numbers per area, and spikelet numbers per panicle. Ripened grain ratio was a similar aspect in all treatments. The palatability score of milled rice was lowest in control while protein content of milled rice was highest in control. The NTCMV was considered an effective sustainable farming practice for rice yield and quality.