• Journal of Korean Neurosurgical Society
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• 제29권11호
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• pp.1461-1468
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• 2000

Objective : The aim of this study is to evaluate clinical outcome of anterior screw fixation for type II odontoid fractures for the prliematim of atlanatoaxial mobility. Methods : Between 1995 and 1999, we treated 15 cases of type II odontoid fractures by anterior screw fixation among 44 cases of odontoid fractures. Thece included 14 males and 1 female aged from 23 to 63 years, with a mean age of 39.7 years. The causes of trauma were traffic accident in 13 cases, slip down in 1 and fall down in 1. The fracture type was type II-P in 7 cases, type II-A in 3, type II-N in 2 and type II-A and P in 3. The fracture line was oblique downward and backward in 6 cases, oblique downward and forward in 3 and horizontally in 6. The range of follow up was 4 to 47 months(mean 26.5 months). Results : Adequate reduction and fixation were obtained in 12 cases. Three cases in which fracture type and line were type II-A and oblique downward forward were failed, so posterior transarticular screw fixation was performed. All except 3 failed cases had adequate cervical movement and stability. There were no operative mortality nor morbidity. Conclusion : Anterior screw fixation provides the best anatomical and functional results for type II odontoid fracture with intact transverse ligament when fracture line is horizontal or oblique downward and backward. But it is limited when fracture line is oblique downward and forward.

• 대한수학회보
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• 제43권4호
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• pp.861-868
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• 2006

We present a Choquet-Deny-type theorem for downward filtering convex sets of continuous functions and show that the Identity Korovkin cone of a downward filtering convex cone S is exactly the uniform closure of S.

• 항공우주시스템공학회지
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• 제15권2호
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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.

• 한국산업융합학회 논문집
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• 제3권3호
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• pp.245-250
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• 2000

This study was carried out to investigate blowing performance for blowing type in space heater. This paper present that power requirement, static pressure, total pressure and static pressure efficiency were increased in proportion to air flow rate. And in the Korean space heater, side ward blowing type was effected than downward blowing type.

• Nuclear Engineering and Technology
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• 제49권5호
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• pp.953-967
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• 2017

In this paper, a complete station blackout (SBO) or complete loss of electrical power supplies is simulated and analyzed in a downward cooling 5-MW pool-type Material Testing Reactor (MTR). The scenario is traced in the absence of active cooling systems and operators. The code nodalization is successfully benchmarked against experimental data of the reactor's operating parameters. The passive heat removal system includes downward water cooling after pump breakdown by the force of gravity (where the coolant streams down to the unfilled portion of the holdup tank), safety flapper opening, flow reversal from a downward to an upward cooling direction, and then the upward free convection heat removal throughout the flapper safety valve, lower plenum, and fuel assemblies. Both short-term and long-term natural core cooling conditions are simulated and investigated using the RELAP5 code. Short-term analyses focus on the safety flapper valve operation and flow reversal mode. Long-term analyses include simulation of both complete SBO and long-term operation of the free convection mode. Results are promising for pool-type MTRs because this allows operators to investigate RELAP code abilities for MTR thermal-hydraulic simulations without any oscillation; moreover, the Tehran Research Reactor is conservatively safe against the complete SBO and long-term free convection operation.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.788-793
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• 2009

Constructing substructures by using Top-Down or Downward method needs an efficient formwork system because of difficulties in supporting concrete slabs from the bottom while excavation is in process. Existing underground formwork systems can be classified by three types: graded ground supported type (Slab On Grade, Beam On Grade), suspension type (Non Supporting Top Down Method), and bracket supported type (Bracket Supported R/C Downward). Each method has its own advantages and limits. Application of a specific formwork system for a given construction site is determined by various conditions and affect construction time and cost. This paper presents a newly developed underground non-supporting formwork system, which combines the advantages of a suspension type and a bracket supported type while it overcomes limits of two types. The developed system has a moving formwork which is supported by suspension cables hanging from the bracket placed at the top of pre-installed substructure columns. Then, the moving formwork is repeatedly lowered down for the next floor below to support concrete slab during curing. The details of this bracket and cable supported system have been investigated for the improvement of easiness in construction.

• Nuclear Engineering and Technology
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• 제54권2호
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• pp.546-553
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• 2022

Narrow rectangular channels are employed in nuclear research reactors that use plate-type nuclear fuels, high heat-flux compact heat exchangers, and high-performance micro-electronics cooling systems. Two-phase flow in narrow rectangular channels is important, and it needs to be better understood because it is considerably different than that in round tubes. In this study, mechanistic models were developed for the flow regime transition criteria for various flow regimes in co-current air-water two-phase flow for vertical downward flow inside a narrow rectangular channel. The newly developed criteria were compared to a flow regime map of downward air-water two-phase flow inside a narrow rectangular channel with a 2.35-mm gap width under ambient temperature and pressure conditions. Overall, the proposed model showed good agreement with the experimental data.

• 동의신경정신과학회지
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• 제19권2호
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• pp.165-193
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• 2008

Objective: The ECG which used for this paper, is analysis result from alogrisms of arrythmia, and we have studied that how we could certain Cold(寒)type or Heat(熱) type and that Deficiency(虛) type or Excess(實)type of organs from various special diseases, and we obtained like these results. Method & Conclusion: 1. we depend on our examination about Pulse(脈) because we can't discriminate arrythmia using ECG analysis instruments. 2. We obtained that Cold(寒) type diseases had wave that prolonged above normal baseline and ST wave which had downward aptitude. 3. We obtained that Heat(熱) type diseases had the fibrillation which had shortend wave that compare to normal and had downward aptitude or negative aptitude. 4. We obtained that Respiratory system (肺) diseases had wave that is within normal or is short of normal range and had much fluctuation in potential difference or trans on P wave. 5. The character of EKG which presented about diseases of gastric systems is prolonged above narmal range of wave, and the ECG had represented mixed wave with Heat(熱) type when accompany inflammatory in gastric system. 6. The wave of Blood Stasis(瘀血) type had upward aptitude of QRS wave, and the wave of anemia or blood loss type(少血) had downward aptitude of QRS wave, the wave which had both Cold(寒)) and Heat (熱) represented mixed waves. 7. The Knotted Pulse(結脈) and Intermittent Pulse(代脈)is corresponded with sinus brady cardia, and the Swift Pulsle(疾脈) is corresponded with fibrillation. 8. We pay attention to the relations of formations about pressures pulse from formations of EMD( electromechanical dissociation ). Result : From these results, we will have to study about ECG which using in tests of change of Parkinsons disease.

• 대한한의정보학회지
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• 제14권1호
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• pp.81-106
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• 2008

The ECG which used for this paper, is analysis result from alogrisms of arrythmia, and we have studied that how we could certain Cold(寒 )type or Heat(熱) type and that Deficiency(虛) type or Excess(實)type of organs from various special diseases, and we obtained like these results. 1. we depend on our examination about Pulse(脈) because we can't discriminate arrythmia using EKG analysis instruments. 2. We obtained that Cold(寒) type diseases had wave that prolonged above normal baseline and ST wave which had downward aptitude. 3. We obtained that Heat(熱) type diseases had the fibrillation which had shortend wave that compare to normal and had downward aptitude or negative aptitude. 4. We obtained that Respiratory system (肺) diseases had wave that is within normal or is short of normal range and had much fluctuation in potential difference or trans on P wave. 5. The character of EKG which presented about diseases of gastric systems is prolonged above narmal range of wave, and the EKG had represented mixed wave with Heat(熱) type when accompany inflammatory in gastric system. 6. The wave of Blood Stasis(瘀血) type had upward aptitude of QRS wave, and the wave of anemia or blood loss type(少血 ) had downward aptitude of QRS wave, the wave which had both Cold(寒) and Heat (熱) represented mixed waves. 7. The Knotted Pulse(結脈) and Intermittent Pulse(代脈) is corresponded with sinus brady cardia, and the Swift Pulsle(疾脈) is corresponded with fibrillation. 8. We pay attention to the relations of formations about pressures pulse from formations of EMD( electromechanical dissociation ). From these results, we will have to study about EKG which using in tests of change of Parkinsons disease.

• 한국해양공학회지
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• 제11권3호
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• pp.132-143
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• 1997

Removal of spilled oil over the sea and the river has become one of the urgent problem in these days. Removing oil using mechanical devices are recommended because chemical dispersion can cause the secondary contamination in the environment. In the present study a series of experiments were carried out to study the effect of working conditions of a belt type skimmer on the rate of recovery for the spilled oil. The oil chosen for the present experiment was diesel oil. Three different situations, namely, upward, downward, up-and-downward pickup have been investigated for various contact angles, belt speeds and oil thicknesses. The results show that the rate of oil recovery for the case of downward pickup with a contact angle of 45.deg. shows the highest among all the conditions. For the removal of spilled diesel oil the optimal belt speed can be found as the critical value to reach the saturated pickup rate for a given oil thickness. The recovery rate of bunker C oil shows 4-6 times higher than that for diesel oil. And the optimal belt speed for bunker C oil can be found less than that for diesel oil for the same slick thickness.