• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.185-199
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• 1999

This study was peformed to investigate the distribution and magnitude of stress at supporting tissue of abutment teeth and residual ridge tissue with remaining unilateral posterior teeth. Four types of removable partial dentures that included clasp retained removable partial denture, attachment retained removable partial denture, telescopic removable partial denture, and swing-lock partial denture were designed, and strain gauge was used for stress analysis. Each prosthesis was subjected to simulated vertical and oblique load. The following conclusions were drawn from this study. 1. The clasp retained removable partial denture generally distributed simulated vertical force more evenly to the supporting structure. 2. The stress at buccal side of 1st premolar was the lowest in swing-lock partial denture and that was highest in attchment retained removable partial denture. The stress at lingual side of 1st premolar was the lowest in telescopic partial denture. 3. In clasp retained removable partial denture, stress was lower at load site and ridge crest at mid-line, but it was higher at 1st premolar area on vertical load. 4. In attachment removable partial denture, stresses at buccal side of 1st premolar. lingual side of 1st premolar on vertical load, and ridge crest at midline on oblique load were higher. 5. In telescopic removable partial denture, stress at lingual side of 1st premolar was the least in all removable partial dentures, but the stress at load site was higher. 6. In swing-lock removable partial denture, stress at buccal side of 1st premolar was the lowest, and stresses at load site and distal end of residual ridge crest were higher.

• Magazine of the Korean Society of Agricultural Engineers
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• v.24 no.3
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• pp.84-91
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• 1982

This study was conducted to investigate the consolidation characteristics of repeated increasing and decreasing load m marine clay. Consolidation test was performed by the whole repetition of increasing and decreasing load and the partial repetition of increasing and decreasing load. The results obtained were as follows: 1. The void ratio e was decreased according to the increase of preloading and the repe- tition of increasing and decreasing load. 2. In case of the partial repetition of increasing and decreasing load the compression index Cc was decreased with the increase of preloading and the repetition of increa- sing and decreasing load 3. The expansion rate was greatly increased with the whole repetition of increasing and decreasing load and it was inclined to be increased with the increase of preloading in case of the partial repetition. 4. The coefficient of volume compressibility were decreased according to the repetition of increasing and decreasing load 5. The secondary consolidation coefficient was decreased with the repetition of increasing and decreasing load. Especially in case of the partial repetition, the peaks of secon- dary consolidation curves could be found to move toward the vicinity of preloading.

• Journal of Energy Engineering
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• v.28 no.2
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• pp.47-54
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• 2019

As absorption type heat pump for waste heat recovery is installed in combined cycle power plant for Energy Service Company, performance test is implemented to confirm the operation data on partial load. The operation data changes according to the heat pump operation on partial load are as follows. Total heat output increases, because waste heat of closed cooling water and a portion of LP steam from HRSG is supplied. But electric power output of steam turbine is reduced, because LP steam to steam turbine is reduced. And heat output from HP district heater and LP district heater is reduced, because HP turbine exhaust steam to HP district heater and LP district heater is reduced. On partial load operation, turbine output reduction is higher than the base load operation. Therefore, on partial load, heat pump should be operated in consideration of the heat output increase and electric power output reduction.

• Plant Journal
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• v.18 no.2
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• pp.32-40
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• 2022

In this study, we investigated the operation data of combined heat and power in accordance with the change of the inlet guide vane with partial load. The partial load 80% could close the inlet guide vane up to 24%, and the exhaust gas temperature could be increased by 52℃. The partial load 90% could close the inlet guide vane up to 12%, and the exhaust gas temperature could be increased by 23℃. At 80% of partial load with the thermal load tracking mode, the output could be increased up to 5.68 MW, the combined cycle efficiency increased by 0.73%, and the combined heat and power efficiency increased by 1.81%. At 90% of the partial load, the output could be increased up to 2.55 MW, the combined cycle efficiency increased by 0.32%, and the combined heat and power efficiency increased by 0.72%.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.1
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• pp.26-33
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• 2004

In general, an absorption chiller or heat pump is operated under the constant cooling water flow rate condition even though the system works with a partial load. The objective of this paper is to study the effect of the cooling water flow rates and the temperature of cooling water on the system performance to find the energy saving methode for the partial load operation of the double effect $H_2O$/LiBr absorption chiller. It is found that the performance of the system is sensitive to the temperature of cooling water than the cooling water flow rate, so the decrease of the performance due to reducing the cooling water flow rate can be overcome with the reduction of the cooling water temperature by 1$^{\circ}C$. The flow rate of the cooling water flow rate ranges from 50％ to 100％ of the flow rate at normal conditions with a partial load. It is also found that the operation cost of the cooling water pump and the cooling tower can be reduced by 23％.

• Journal of Aerospace System Engineering
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• v.15 no.2
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• pp.10-15
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• 2021

The propeller wake of tiltrotor-type aircrafts, such as TR-60 and quad tilt propeller (QTP) UAV, in hover substantially impinges the upper surface of the primary wing and generates a downward load. This load is directly proportional to the thrust of the propeller and reduces the available payload. Therefore, wing and nacelle mechanisms should be carefully designed to reduce downward load. This study conducted a numerical analysis of the rotating propeller in hover to predict the downward load of a QTP UAV. An unsteady three-dimensional Navier-Stokes solver was used along with a sliding mesh for the simulation of the rotating propeller. To reduce the downward load, the tilting mechanisms of the partial wing and nacelle were simultaneously introduced and numerically analyzed. Finally, the downward load was predicted by 14% of isolated propeller thrust; further, the downward load could be reduced by adopting the partial wing and nacelle tilting concept.

• Journal of Technologic Dentistry
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• v.28 no.2
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• pp.331-346
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• 2006

Free-end partial dentures, which are supported by teeth surrounded by dental root membranes and elastic mucous membrane tissues, may cause stress to the abutment teeth due to external force imposed on the denture base, increase the mobility of the abutment teeth, and bring about a change in the periodontal tissue. General retainers used in partial dentures are categorized into clasp, attachment, and Konus crown. Stress imposed on the abutment teeth and mobility of the denture base have relations with the lifetime of a crown and abutment teeth, and have direct relations with the chewing ability. Thus, a need arises to make a comparative analysis of stress of the three direct retainers on the abutment teeth and interpret the mobility of the denture base. This study designed three kinds of removable partial dentures (one kind of attachment partial denture, one kind of Konus crown partial denture, and one kind of clasp partial denture), and fabricated Dentiforms of bilateral partial dentures (Kennedy Class I) with lower left 1st premolar and lower right 1st and 2nd premolars being as the abutment teeth. A strain gauge was installed in the mesial and distal surface of the lowerr left 1st premolar (No. 34) of the fabricated dentiform and in the lower part of the denture base, and installed were a clasp partial denture, an attachment partial denture, and a Konus crown partial denture. Then, the vertical static load of 5kgf and 7.5kgf at the occlusion surface of the lower left No. 6 molar was generated for a total of 20 frequencies of load each using a push-full gauge, and thus a change in the output of the strain gauge was measured. With the respective application of Konus crown, attachment and RPI clasp in the free-end partial denture, surveyed was the distribution of stress imposed on the abutment teeth and the denture base according to the location of occlusion force load so as to come up with the following results. 1. Konus crown and attachment partial dentures generated much stress, and more stress on the abutment teeth than RPI clasp dentures did. Attachment dentures tended to further intensify stress on the abutment teeth than Konus crown dentures did. 2. Attachment dentures and Konus dentures imposed less stress on the denture base than RPI clasp dentures did. There was no stress difference between Attachment and Konus crown dentures. 3. Dentures that were designed with the application of retainers using sturdy linkage methods tended to be less mobile.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.3
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• pp.322-330
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• 2005

Statement of problem. In distal extension removable partial denture, the preservation of health of abutment teeth is very important, but abutment teeth are subjected to unfavorable stress. Purpose. The purpose of this study was to investigate the biomechanical effects of mandibular removable partial dentures with various prosthetic designs using strain gauge analysis. Material and methods. Artificial teeth of both canines were anchored bilaterally in a mandibular edentulous model made of resin. Bilateral distal extension removable partial dentures with splinted and unsplinted abutments were fabricated. Group 1 : Clasp-retained mandibular removable partial denture with unsplinted abuhnents Group 2 : Clasp-retained mandibular removable partial denture with splinted abutments by 6-unit bridge Group 3 : Bar-retained mandibular removable partial denture Strain gauges were bonded on the labial plate of the mandibular resin model, approximately 2 mm close to the abutments. Two vertical experimental loadings (100N and 200N) were applied subsequently via two miniature load cells that were placed at mandibular first molar regions. Strain measurements were performed and simultaneously monitored from a computer connected to data acquisition system. For within-group evaluations, t-test was used to compare the strain values and for between-group comparisons, a one-way analysis of variance (ANOVA) was used and Duncan test was used as post hoc comparisons. Results. Strain values increased as the applied load increased from 100N to 200N for all groups (p<.05). The strain values of group 1 and 2 were tensile under loadings. In contrast, strain values of group 3 were compressive in nature. Under 100N loading, group 1 showed higher strain values than group 3 in absolute quantity (p<.05). Under 200N loading, group 3 showed higher strain values than group 1 and 2 in absolute quantity (p<.05). Group 1 showed higher strain values than group 2 (p<.05). Conclusion. Splinting of two isolated abutments by bridge reduced the peri-abutment strain in comparison with unsplinted abutments. Strain of bar-retained removable partial denture increased much more as applied load increased, but was compressive in nature.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.99-105
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• 2014

This paper presents a comparison of operating characteristics for industrial water cooler with variation control methods. The performance analysis regarding the characteristics of condensation capacity, evaporation capacity, compressor load, COP of an on-off type cooler, a hot gas-bypass control type cooler and an inverter control type cooler with respect to the system load is reviewed, respectively. The primary results are as following: the variation of required compressor load of an on-off type cooler with respect to load is 5%, that of hot gas-bypass type is 18% and 66% for an inverter control type cooler. As the result shows, an inverter control type yields relatively huge difference of required compressor load compared to other types of control system. In terms of partial load, COP of an inverter control type cooler presents the highest value, and is considered as the optimized type for the used of the system involving frequent partial load.

• Plant Journal
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• v.4 no.3
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• pp.60-65
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• 2008

Power plant industry has been developed at high-capacity, high-technology, and innovation. Steam turbine became the most useful equipment that dominate more than 50% of all the world electricity production. And developed new materials of the turbine blade and extended length of the turbine last blade brought reform in steam turbine performance upgrade. In this paper, when do partial load driving in high-capacity steam turbine, optimum driving method found whether there is something. In operating steam turbine, there is a lot of loss from secondary wake and throttle of the 1st stage nozzle by the biggest leading factor that load fluctuation affects in high-pressure steam turbine performance. Effect of internal efficiency by 1 stage nozzle is the biggest here, but here fluid flow and flow analysis were not yet examined closely definitely. So, Analyzed design data and acceptance performance test result to applying subcritical pressure drum type 560 MW, supercritical-pressure once through type 500 MW, and 800 MW steam turbines actually. In conclusion, at partial load driving, partial arc admission(PAA) is more efficient than full arc admission(FAA) efficiency. This is judged by because increase being proportional with gross energy of stream that is pressure - available energy if pressure of stream that is flowed in to the turbine increases, available energy becomes maximum and turbine efficiency improves. Therefore, turbine performance is that preview that first stage performance fell if decline is serious in partial load because first stage performance changes according to load.