• 수산해양기술연구
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• 제28권2호
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• pp.157-163
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• 1992

In this paper, the relationship between static pressure recovery and turbulent energy was presented in case of swirling flows into a conical diffuser. The distributions of turbulent energy in a diffuser sectional area were measured by a hot wire anemometer. The following conclusion can be drawn from the experiment. Diffuser loss is constituted by a dynamic pressure loss and total pressure loss. The static pressure recovery depends strongly on the total pressure loss. The static pressure recovery depends strongly on the total pressure loss, and the turbulent energy varies inversely as the static pressure recovery coefficient.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.139-142
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• 2009

In this study, the performance degradation of SOFC single cell caused by the delamination between a cathode and an electrolyte is investigated. As the delamination rate increases, the voltage sharply decreases due to the decrease of reaction sites and losses increase. The current is concentrated to the intact area so that the current density is increased and the ohmic loss and the activation loss become higher. Most part of loss is due to the ohmc loss of electrolyte.

• Food Science and Biotechnology
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• 제14권5호
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• pp.628-633
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• 2005

Muscle fiber characteristics were evaluated for predictability of meat quality traits using 231 crossbred pigs. Muscle $pH_{45min}$, R-value, and $pH_{24hr}$ were selected to estimate regression equation model of drip loss and lightness, although variances of coefficient estimates could only account for small part of drip loss (about 16.3 to 25.3%) and lightness (about 16.9 to 31.7%). Muscle $pH_{24hr}$ was represented to drip loss and lightness, which explained corresponding 25.3 and 31.7% of estimation in drip loss and lightness, respectively. Area percentage of type IIb fiber significantly contributed to prediction of metabolic rate and meat quality. However, equations predicting meat quality traits based on area percentage of type IIb fiber alone are less useful than ones based on early postmortem parameters. These results suggest estimated model using both metabolic properties of muscle and postmortem metabolic rate could be used for prediction of pork quality traits.

• The Journal of Advanced Prosthodontics
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• 제10권2호
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• pp.163-166
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• 2018

PURPOSE. The marginal bone loss of implants with laser treated surface was investigated after six weeks of loading after implant installation to the mandible molar area. MATERIALS AND METHODS. A total of 23 implants were placed in the edentulous molar area of the mandible: 13 implants were immediately loaded and 10 implants were early loaded. The implants used were made of titanium grade 23, screw shaped, 4.2 mm in diameter, and 10 mm in length. Patients were evaluated with resonance frequency analysis at implant fixture installation and 1, 2 (final prosthesis installation), 3, 5, 8, and 14 months later. X-rays were taken at 2 months after fixture installation and 1, 2, 3 years after to measure the marginal bone loss. RESULTS. The mean ISQ value measured at the implant installation was over 70 at all-time points. The average of marginal bone loss was average 0.33 mm. CONCLUSION. Immediate implant loading for laser treated implants would be possible.

• 한국전자파학회지:전자파기술
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• 제4권2호
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• pp.4-10
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• 1993

이동통신에서, 전파경로는 이동국의 위치변동때문에 시간 및 공간에 따라 변한다. 전파경로 손실은 주 파수와 거리뿐만 아니라 안테나 높이, 지형구조와 인위적 환경에 따라 탄라지브로 이동 전파신호의 전파 경로손실을 예측하기는 매우 어렵다. 본 고에서는 대전 및 서울 지역에서 전계강도를 측정하여 단구간 중앙치,500m 거리별 평균치 및 표준 편차를 산출하여 분석하였다. 분석 결과, 경로손실 특성이 예측모텔과 유사하였으며, 특히 단구간 중앙치 는 기지국 안테나 높이, 지형구조와 인위적 환경에 의존하며, 표준편차는 2-1OdBuV사이에 있음을 알 수 있다.

• Fisheries and Aquatic Sciences
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• 제2권2호
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• pp.210-217
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• 1999

Chemical oxygen demand (COD), phytoplankton cell number and chlorophyll-a concentration (Chl-a), sediment mean grain size and ignition loss were studied to determine their temporal trends in the study area. Historical data of COD, cell number and Chl-a were gathered from the late 1960s or early 1980s to 1997, and trends in temporal domain were obtained from a simple regression. Sediments for grain size and ignition loss (as organic contents in sediments) were sampled from the Chokchon macrotidal flat bimonthly from September 1990 to November 1996, and were analyzed using the decomposition method of time series analysis. In general, the first three data showed increasing trends based on regression analysis. The trends of sediment grain size fluctuated in a neutral pathway while those of ignition loss yielded no increasing pattern. In contrast with the suggestions from Ahn and Choi (1998) who reported a coarsening variation in sediment grain size to be a cause of the directional and remarkable changes of macrofaunal communities in this area, we could not find such a corresponding variation pattern from our samples. In diagnosing eutrophication, a paradoxical phenomenon was encountered between the trends in water column (COD, cell number and Chl-a) and sediment (ignition loss) data. In this paper, we inferred the possible processes that produce the discrepancy. Some explanations and biological responses to eutrophication were predicted and discussed.

• 한국농공학회지
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• 제10권1호
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• pp.1413-1419
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• 1968

Yochon reservoir was consturcted with an original storage capacity of 202.7 chung-meters. This reservoir receives the water from watershed area of 933.0 chungbo and has irrigated area of 478.0 chungbo. In 1967 a detailed capacity survey of this reservoir was carried out by a new depth-recorder under the scheme of reservoir sedimentation of Agricultural Engineering Research Center. Significant findings are 1. The capacity of the reservoir for the water storage has been reduced by 8.9%(18.066 chung-meters out of the 202.7 chung-meters) since its construction, a period of just 39.0 years. 2. The sediment accumulation in the reservoir represents an average annual soil loss of 0.496mm depth(0.463 chung-meters) of soil from the watershed area of 933.0 chungbo. Eventually the capacity of the reservoir for the water storage will be reducing by about 25%(50.7 chung-meters out of the 202.7 chung-meters)in one hundred years since its construction. We have to set up controlling projects for those reservoir protections from the sediment, soil loss, and other failures. The depth recorder is very useful, convenient, and accurate machine for surveys of reservoir capacity and other river surveys.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.37-40
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• 2002

It is to show the problems of the existing techniques to estimate agricultural water demand and to suggest the new methods considering the water demand for non-irrigated area and decrease of water loss in canal. It is to suggest the methods to improve the techniques for estimating agricultural water demand and to analyze the water demand and supply according to the facilities capacity. Until now, the concept of per the unit used to estimate agriculture water demand is useful to estimate demand, but is insufficient to cope with the variations of conditions in future. And the paddy area of government is not realistic against a trend of decrease. Water demand decrease is caused by constructions of irrigation facilities as constructing of irrigation canal, but application loss ratio is fixed. Increase of the water demand owing to the increase of the yield per the unit area is also the actual condition which is not considered. The guide-line must contain these contents for a demand estimate.

• 한국농공학회지
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• 제39권3호
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• pp.43-51
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• 1997

The nutrients runoff including nitrogen and phosphorous was investigated to find out the characteristics of nutrient discharge from the slurrigated area using digested animal manure. The results obtained are summarized as follows: 1.The concentrations of T-N, $NH_4$- N, EC, T- P and Cl- were high in flood runoff. 2.The concentration of nutrients by the surface runoff, except for $NO_3$-N, showed a tendency of increasing when the period of dry days before the rain fall was long. And the concentration of N$NO_3$-N increased in the inflow section where subsurface drainage flowed in. 3.The quality of water was generally influenced by the discharge of water quantity from slurrigated area. However the runoff concentration influenced the water quality when it was high enough. 4.To reduce loss of the nutrients and improve the fertilization effect, it is not recommended to apply slurry in rainy season.

• Journal of Periodontal and Implant Science
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• 제42권1호
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• pp.20-24
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• 2012

Purpose: The purpose of this study was to evaluate the soft tissue and bone change around two adjacent implants in onestage implant surgery. Methods: Eleven subjects (7 males, 4 females) who were needed placement of 2 adjacent implants in the molar area were included. The two implants were placed with the platform at the level of the alveolar crest. The interproximal bone between the 2 implants was not covered with gingiva. After surgery, an alginate impression was taken to record the gingival shape and radiographs were taken to evaluate implant placement. Using a master cast, the gingival height was measured at baseline, 4 weeks, and 12 weeks. In the radiograph, the alveolar bone level was measured at the mesial and distal side of both implants at baseline and 12 weeks. Results: The exposed bone was covered with gingiva at both 4 and 12 weeks. Loss of alveolar bone around implants was found in all areas. The alveolar bone level in the exposed bone area did not differ from that in the non-exposed area. Conclusions: This study showed that the alveolar bone level and gingival height around 2 adjacent implants in the exposed bone area did not differ from that in unexposed bone area.