• 대한의생명과학회지
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• 제23권2호
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• pp.73-79
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• 2017

Pulse pressure is an independent risk factor for cardiovascular disease. The aim of the present study was to assess the association between pulse pressure and metabolic syndrome in Korean men. The study subjects were 8,439 adults aged 40 to 64 years, who underwent health screening examination from January 2012 to December 2014 at the Health Promotion Center of one hospital in Gyeonggi-do for general health check-up. They include the metabolic syndrome absent group (Absent, n=3,078), the pre-metabolic syndrome group (Pre-MetS, n=4,242) and the metabolic syndrome group (MetS, n=1,119). Progressive increase in pulse pressure was demonstrated for increasing components of the metabolic syndrome (P<0.001). The pulse pressure according to the degree of the metabolic syndrome was higher in the pre-MetS and MetS groups compared to the Absent group (P<0.001). Systolic and diastolic blood pressure, total cholesterol, triglyceride, fasting glucose, and abdominal obesity positively correlated with pulse pressure (P<0.001).

• 한국농공학회논문집
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• 제58권6호
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• pp.71-77
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• 2016

This study was to evaluate the feasibility of pre-consolidation pressure distribution characteristic of western and southern coastal region, using correlation of unconfined compressive strength and preceding research equation. Pre-consolidation of western and southern region showed similar trends undrained shear strength and pre-consolidation pressure in proportion to unconfined compressive strength. Predicted results of U.S. NAVY. (1982) equation revealed a small error western 9.7 % and southern 0.4 %. Prediction correlation results of pre-consolidation using unconfined compressive strength revealed an error western 16.8 % and southern 0.7 %. It was reported that less than 20 percent of pre-consolidation pressure prediction result of Casagrande forecasting error. Estimates of pre-consolidation pressure are possible, before the standard consolidation test, because it was reported that less than 20 % of the forecasting errors of Casagrande.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2071-2075
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• 2003

Pressure variation is one of the major sources on noise emission in the oil hydraulic piston pumps. Therefore, it is necessary to clarify about pressure variation characteristics of the oil hydraulic piston pumps to reduce noise. Pressure variations in a cylinder at trapping region were measured during pump working period with discharge pressures, rotational speeds. The effect of pre-compression of the discharge port with three types valve plates also investigated. It was found that the pressure variation characteristics of oil hydraulic piston pumps deeply related with pre-compression design of the discharge port. Also, it was found that the pressure overshoot at trapping region can reduce by use of pre-compression at the end of the discharge port in valve plate

• 한국농공학회지
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• 제18권4호
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• pp.4242-4250
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• 1976

The determination of the pre-consolidation load known to have a great effect on the consolidation characteristics of the soil have been researched and discussed in detail by many other researchers. A study was undertaken to investigate and compare the effect of pre-consolidation loads on the coefficient of permeability and the consolidation characterisics of soil through the consolidation test on the three types of soil samples. The results of this study are follows; 1. Large compression index is dependent on initial void ratio of the sample being used and the pressure-void ratio curve shows a curved linear relationship in over-consolidated area but a linear relationship in normally consolidated area.2. Settlement-time curve is S-shaped where the pressure is larger than pre-consolidation load and regardless of over-burden pressure, it is a similar straight line respectively in the secondary consolidation area. 3. Primary consolidation ratio of the sample increases almost linearly with the increase of over-burden pressure but the coefficient of volume compressibility decreases linearly with the increase of it. 4. Time factor of a certain degree of consolidation increases with over-burden pressure but the coefficient of consolidation decreases with it in over-consolidated area. There is a linear relationship between them in normally consolidated area. 5. The void ratio of completion point of primary consolidation decreases linearly with over-burden pressure. 6. The coefficient of permeability of sample decreases linearly with over-burden pressure in normally consolidated area, also it increases linearly with increment of the void ratio of the sample.

• 유통과학연구
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• 제17권5호
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• pp.5-17
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• 2019

Purpose - This study aims to exploratorily analyze relationship among pressure on business failure, social safety net perception, and entrepreneurial intention targeting potential business founders - pre-entrepreneurs and re-entrepreneurs. Research design, data, and methodology - Out of 450 collected surveys, 386 were used for analysis. Among these, 216 were from pre-entrepreneurs and 170 were from re-entrepreneurs. Frequency analysis, reliability and validity analysis, and regression analysis were performed. Results - In analysis of pre-entrepreneur and re-entrepreneur's pressure on business failure and social safety net perception, objective environment perception - a subfactor of social safety net perception - had statistically significant difference between the two potential entrepreneur groups. Conclusions - We categorized potential entrepreneurs into pre-entrepreneurs and re-entrepreneurs. Also, the current study suggests importance of social safety net to vitalize food service business startup by validifying its mediating effect between pressure on business failure and attitude towards restaurant business establishment. This research also established groundwork for future studies on ways to improve entrepreneurial intention or startup business sustainability by deducing social safety net perception difference between pre-entrepreneurs and re-entrepreneurs. This study was able to analyze relationship between those two groups in terms of entrepreneurial intention and startup business sustainability.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.484-487
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• 2005

This paper presents an analytical approach to describe the variation in the vibration characteristics such as the natural frequency of a piezoelectric transducer under static pre-pressure. The transducer considered in this paper is a bolt clamped Langevin type transducer, which consists of a couple of piezoelectric discs, a couple of metal blocks for added mass effect, and a bolt to tighten them. A new analysis model for the transducer has been developed by taking into account the contact area between the piezoelectric ceramic and the metal block. The variation of the resonance frequency due to the pre-pressure has been calculated compared with other results.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제20회 KOSCO SYMPOSIUM 논문집
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• pp.85-92
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• 2000

End-gas temperatures were measured using CARS technique in a conventional DOHC spark-ignition engine fueled with PRF80. The measured pressure data were analyzed using band pass filter method. The measured CARS temperatures were compared with adiabatic core temperatures calculated from measured pressure. Significant heating by pre-flame reaction in the end gas was observed in the late part of compression stroke under both knocking and non-knocking condition. CARS temperatures measured at 10 crank angle degree before knock occurrence was higher than adiabatic core temperatures. These results indicate that there exist some exothermic reactions in low pressure and temperature region. CARS temperatures began to be higher than the adiabatic core temperature when the end-gas temperatures reached 700 K. The temperature elevation due to the pre-flame reaction correlated better with CARS temperature than with cylinder pressure.

• 한국소음진동공학회논문집
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• 제16권1호
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• pp.89-100
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• 2006

This paper presents an analytical approach to describe the variation in the vibration characteristics such as the natural frequency of a piezoelectric transducer under static pre-pressure. The transducer considered in this paper is a bolt-clamped Langevin-type transducer, which consists of a couple of piezoelectric discs, a couple of metal blocks for added mass effect, and a bolt to tighten them. A new analysis model for the transducer has been developed by taking into account the contact area between the piezoelectric ceramic disc and the metal block. The variation of the resonance frequency due to the pre-pressure has been calculated and compared with measured results reported earlier.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1309-1310
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• 2011

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.737-740
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• 2002

Pressure fluctuation in the cylinder is one of the major sources on noise emission in oil hydraulic piston pumps. This paper reports an experimental study of pressure fluctuation characteristics in the cylinder of oil hydraulic piston pumps. We measured pressure fluctuation at BDC with delivery pressure, rotational speed. Because the pre-compression and the V-grooves in the valve plate is known of noise reduction, we investigated also the effect of pre-compression and V-grooves at the ends of the kidney ports with four types valve plates. We found that the pre-compression and the V-grooves in valve plate could reduce the noise of oil hydraulic piston pumps.