http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정석조 한국육수학회 1973 생태와 환경 Vol.6 No.1·2
This feeding experiment was run to determine the growth, health and general appearance of rainbow and lake trout fry in relation to the protein and oil levels in their diets. Results indicated that feed conversions and growth improve considerably with added protein and fat in diets fed to rainbow trout fry. An excess amount of protein and fat can increase the calories and protein required per 100 grams of fish gain and therefore lower the efficiency of the diet. Results indicated that lake trout fry have an increased requirement for protein per 100 grams of fish gain than do the rainbow. A protein sparing action was observed in a high fat content diet.
鄭錫祚,孫再根 慶北大學校 農業科學技術硏究所 2005 慶北大農學誌 Vol.23 No.-
The purpose of this study was carried out to determine the optimum sowing date and days after sowing (DAS) in automatic facility located at Uiseong of Gyeoungbuk province. The seedling height was rapidly increased with a delay of sowing time from April to May. The 10-day old seedlings with suitable plant height(>10cm) for machine transplanting in the facility were obtained when the seeds sowed after May 20 at Uiseong in Gyeoungbuk province. The dry weight-height ratio of 10-day old seedlings was significantly decreased when the seeds sowed after June 20, and 15-days old seedlings did after May 10. No. of panicles/hill was reduced with increasing of days after seeding. But there were no significant difference among other yield components such as no. of grains/panicle, ratio of ripened grains, and 1,000 grain weight. The highest grain yield, 748kg/10a, was attained from the 10-day old seedlings transplanted at May 27 in comparision with those of 15-day and 20-day old seedlings. The grain yield of 10-day old seedlings transplanted at June 26 was also higher than that of 15-day old seedlings.
솔-젤법에 의한 Nb_2O_5-Fe_2O_3 혼합산화물의 제조 및 산 특성조사
정석조,양희정,권재범,이내우,우희철 釜慶大學校 2000 釜慶大學校 論文集 Vol.5 No.-
In this study, some of results from a study conducted on the preparation of niobium coated hematite particles to be used as a catalyst are presented.α-Fe_2O_3 (hematite) particles obtained by aging an acidic solution of ferric(Ⅲ) ions at high temperature were first prepared as core particles and synthesised by hydrolysis at high temperature with layers of amorphous niobium pentaoxide (Nb_2O_5) deposited by the hydrolysis of niobium pentachloride. The effects of varying molecular ratio of Nb/Fe (10/1, 5/1, 1/2, 1/5, 1/10) were studied. The synthesised particles were characterized for their physical and chemical properties using XRD, SEM, TPD, BET etc. The process of the surface coating showed heterocoagulation rather than surface nucleation and growth. A preliminary investigation of the acidic characterization and specific surface area of the synthesised particles showed that these particles can achieve an acidic characteristic changed and enhanced specific surface area of that of pure niobia and α-Fe_2O_3 prepared here.
이악물기 치아접촉시 편측 구치 상실을 지닌 두개골의 부하 분석
정석조,김용철,강동완 朝鮮大學校 口腔生物學硏究所 2001 口腔生物學硏究 Vol.25 No.2
The purpose of this study is to analyze the mechanical stress and displacement during the simulated bilateral clenching task on the 3D finite element (FE) model of the dentated skull with unilateral molar loss. For this study, the computed tomography (G.E.8800 Quick, USA) was used to scan the total length of human skull in the frontal plane at 2.0㎜ intervals. The fully assembled finite element model consists of the articular disc, maxilla, mandible, teeth, periodontal ligament and cranium. The EF model was used to simulate the bilateral clenching in intercuspal position. The loading condition was the force of the masseter muscle exerted on the mandible as reported by Korioth et al. degrees of freedom of the zygomatic region where the masseter muscle is attached were fixed as restraints. In order to reflect the actual action of the muscles force, the displacement of the region was attached where the muscle is connected to the temporal bone and restraint conditions were given values identical to values at the attachment region of the masticatory muscle but with the opposite direction of the reaction from when the muscle force is acted on the mandible. Although the mandible generally has higher displacement and von Mises stress than the maxilla, its mandibular corpus on the molar-loss side has a higher stress and displacement that the molar-presence side. Because the displacement and von Mises Stress was the highest on the lateral surface of mandibular corpus with molar loss, the stress level of the condyle on the molar-loss side is greater than that of the molar-presence side, which in turn caused the symphysis of the mandible to bend. In conclusion, the unilateral posterior bite collapse with molar loss under para-functional activities such as bruxism and cleanching can affect the stress concentration on the condyle and mandibular corpus. It is therefore necessary to consider the biomechanical function of dento-skeleton under masticatory force while designing the occlusal scheme of restoration on alveloar bone with the posterior collapse.
임플란트 보철의 abutment 유무에 따른 유한 요소법적 응력분석
정석조,이준규,정재헌 朝鮮大學校 口腔生物學硏究所 1997 口腔生物學硏究 Vol.21 No.1
The attraction to endosseous implants lies in the potential for improved function, improved esthetic, and more favorable stress distribution in the superior prostheses, fixture, and supporting bone. Implant for single tooth replace is especially needed esthetics, and that was mainly established by use of various superstructure. The purpose of this study was to compare the stresses in implant prosthesis and fixture, and supporting bone according to with or without abutment between fixture and superstructure. Using the finite element method, this study modeled 4.0×14㎜ cylindrical type implant fixture with the external hexed type of 0.75㎜, and two models are completed. Model A is without abutment, so implant superstructure is direct connected in fixture, and Model B is with abutment on the fixture. The vertical load of 200N and 30°lateral load of 100N were applied at the cusp tip of the prostheses. The results were as follows ; 1. Under vertical and lateral loading, the amount of displacement was larger at the model B with abutment than at the model A without abutment. 2. Under vertical and lateral loading, less equivalent stress was represented at the model B with abutment than at the model A without abutment. 3. Under vertical and lateral loading, model B with abutment showed more stress in fastening screw than at the model A without abutment. 4. Under vertical and lateral loading, model B with abutment showed less stress distribution in fastening screw than at the model A without abutment. As the results of this study, in case of using abutment between implant fixture and final prostheses, large displacement is occured and the stresses is concentrated at the fastening screw. The other hand, when the implant superstructure is direct conected to implant fixture without abutment, less displacement is occured and the streses is widely distributed to the supporting bone. That results mean intermittent abutment acts stress blocker and when the use of abutment, fasening screw fracture more occured than supporting bone resorption.