• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.90-99
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• 2002

The main purpose of this study lies on the development of micro dilution tunnel based on the Sierra Dilution chamber model. As a primary examination, characteristics of flow and temperature distributions during the steady dilution process in dilution chamber are observed with numerical analysis. The penetration of dilution air through porous tube as well as wall temperature and temperature gradient inside porous tube are examined. The thermophoretic velocity in terms of temperature behavior inside porous tube are defined and examined. Based on the ratio of penetration and thermophoretic velocities, all part of porous tube are shown to be safe from the particulate depositions. However, The inlet portion of porous tube in addition to the portion of impinging of dilution air are marginally safe from the particulate depositions. Generally the safer design against particulate deposition is required in provision f3r steady dilution process and for transient process as well.

• Journal of Mechanical Science and Technology
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• v.14 no.2
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• pp.177-187
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• 2000

Dilution is an important factor which influences the properties of clad layer. In this paper the change of dilution during laser cladding and the control of dilution are simulated by a finite element method. The adaptive mesh method is adopted for the time-dependent finite element method computation so that the shape of melt pool can be well represented. The situation of the width control of melt pool is also simulated, which indicates that the dilution can be controlled if the width of melt pool is controlled. Computational results indicate that if a line energy (input energy per unit distance) remains constant the dilution will increase with time, especially at the beginning. Simulation results show that it is possible to control dilution in a certain range if the line energy decreases with time. Experiment of Nd: YAG laser cladding with wire feeding is performed. Experiment results coincide well with the FEM results.

• Journal of Biosystems Engineering
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• v.2 no.1
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• pp.1-6
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• 1977

The dilution of crankcase oil with unburned portions of the fuel during operating is one source of the oil contaminations which will reduce engine life.It has been learned that major causes of oil dilution may be the result of using impure fuels which were mixed with water, dust, and some others, but very little was known about this. This study was conducted to develop a more intimate understanding about oil dilution of the farm kerosene engine while using impure fuel mixed with expecially diesel. Fuels being used in this study were 9 kinds of mixed fuels, kerosene and diesel. Farm kerosenen engine of 10 P.S. was tested at no-load of 1000 and 2000 rpm., such as 1/4, 2/4, 3/4, 4/4, and 11/10 loads for understanding about oil dilution of keresene engine.The result of this study are summarized as follows : 1. The amounts of oil dilution of the engine being tested was increased with increase in the applied loads and the contents of diesel in the mixed fuels when using fuels other than kerosenen and diesel, whereas at $D_100$ fuel the comount of oil dilution decreased in some cases. The lowest value was measured to be 20 cc/hr, at $K_90$ fuel of no-load condition, and the highest value to be 293cc/hr. at $K_{10}$ fuel of 4/4 load condition. 2. When the engine was operated at no-load condition, the amount of oil dilution at 100rpm. was much more than at 2000 rpm. 3. Because the fuel consumption and the oil dilution showed a similar tendency along the applied loads, the excessive fuel consumption of engines was supposed to be one of the important factors affecting oil dilution. 4. The temperature of crankcse oil was varied invesely with oil dilution, but they were not thought to be factors to determine each other variable. 5. The tested engine could be operated with high percentage of diesel mixed fuel from no-load condition to fully loaded condition, but it would be impossible to operate the engine for long hous continuously due to excessive speed fluctuation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.5
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• pp.535-539
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• 2010

We present a digital dilution chip comprising a $2{\times}6$ array of wells; the chip can be employed to change the dilution ratio as well as to initiate reactions among diluted samples by using the inter-well valve around the well. In previous dilution devices, streams comprising sample and dilution solutions were merged and separated by a branched microchannel. Therefore, the dilution ratio could not be changed until the structure of the branched microchannel was changed. The present device merges and splits the wells filled with sample or dilution solution by controlling inter-well valves around the wells. Thus, it is possible to change the dilution ratio by changing the sequence in which merging and splitting sequence of each well filled with sample or dilution solution. In experiments, we found that the chip could be used to change linear or exponential dilution ratios within an error of 16.7% and to initiate reactions among the samples within a reaction error of 17.7%.

• KSBB Journal
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• v.11 no.4
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• pp.476-480
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• 1996

Using Pseudomonas sp. B3, identified and isolated from nature, wastewater containing phenol was treated in a continuous stirred tank reactor and its reaction characteristics were studied. Average concentrations of phenol and COD in effluents were 1.5mg/L and 124mg/L at 0.059h-1 dilution rate, respectively. At the dilution rate higher than 0.063h-1, phenol and COD increased abruptly to 19mg/L and 318mg/L. At the dilution rate higher than 0.059h-1, biomass concentration suddenly decreased and was "washed out". Biomass concentration was 150mg/L at a dilution rate of 0.067h-1. Maximum biomass production rate was 15.98mg/L$.$h at a dilution rate of 0.067h-1. When dilution rate increased above 0.059h-1, effluent phenol concentration abruptly increased and biomass production rate decreased. Maximum cell growth rate(${\mu}$max) and Michaelis-Mentens kinetic constant(Ks) were 0.074h-1 and 0.424mg/L, respectively. From the above result low phenol concentration can be expected at a maximum dilution rate, but reactor becomes unstable due to phenol inhibition.

• Ocean and Polar Research
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• v.22 no.1
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• pp.45-56
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• 2000

Hydrodynamic mixing characteristics of submerged effluent discharges into Masan Bay were investigated by both field observations and numerical model simulations. CORMIX model, a length-scale mixing model, was adopted to obtain the near-field dilution and wastefield characteristics of the effluent discharges into Masan Bay. Model predictions of the near-field dilution rates were in a good agreement with field observations in summer and winter seasons. Seasonal variations in the dilution rates showed that the highest dilution rate was obtained in winter while the lowest dilution rate was in summer. As the effluent discharges are increased with the treatment capacity expansion to be completed by 2011, the dilution rates are expected to be much reduced and the near-field stability of the wastefields will become unstable due to the increased effluent discharges.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.1
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• pp.40-48
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• 1987

A Mini-Dilution Tunnel is described as a scaled down comparision of a Standard Tunnel. The paper presents the result of experimental investigations on measuring the particulate emission of a diesel engine in a Mini and a Standard Dilution Tunnel. The result offers a contribution to understanding about the influence of several parameters including dilution ratios, mixture temperatures, mixture conditions, filter temperatures, and flow conditions. In the experiment either increasing the filter temperature and mixture temperature at a fixed dilution ratio or increasing the dilution ratio at a fixed filter temperature and mixture temperature resulted in a decrease in the total particulate mass. These changes in total particulate mass were attributed to the changes in the soluble organic fraction of the particulate sample. Also, mass differences between the Mini and the Standard Dilution Tunnel for the same engine conditions were within approximately 15% of each other.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.73-76
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• 2013

The inert gas dilution effect for the stability of a stratified propane premixed flame has been experimentally studied. The addition of inert gases to a stratified premixed flame, which used to be very stable without dilution, makes a flame unstable. The lower equivalence ratio on the outer premixed flame and the lower fuel flow rate through the inner nozzle were observed to be the more stable conditions for the stratified premixed flame with nitrogen or argon dilution. It has been interpreted with the flame structure change such as shift of stoichiometric ratio region in a flame.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.1
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• pp.63-76
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• 2011

The potential for brand dilution occurs when new brands merge with an identical image of a parent brand. Despite the significant attention regarding the effects of dilution on brand extension, there is limited research on brand dilution in the beauty industry. This study analyzes the effect of the typicality of extensional type on brand attitude or purchase intention for potential dilution toward beauty brand extension. In addition, we examine the moderating effect of knowledge transfer when customers evaluate the typicality of the extensional type for potential dilution toward beauty brand extensions. For the experiment, 4 description type factorial designs were performed. A total of 219 students participated in the experiment who had experience of visiting a beauty salon. The results are as follows. First, there are significant independent and interaction effects between the typicality and extensional type that reveals differential influences on the attitude or purchase intentions toward extended beauty brands. Second, the knowledge of the parent brand is transferred to extended brands. Third, there is a significant moderating effect of knowledge transfer, as customers evaluate the typicality of the extensional type for the potential dilution toward beauty brand extension. This study provides some theoretical and practical perspectives with some limitations.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.98-102
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• 1996

This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.