炭素鋼의 表面完成處理가 疲勞强度에 미치는 影響

鄭鳳秀 空軍士官學校 1967 論文集 Vol.2 No.-

This paper represents the results of an investigation of the effect of surface finishing treatments on the fatigue strength of tempered carbon steel at Rockwell hardness level of C-40. These tests revealed: (1) Peening and blasting treatment gave increased endurance limit as high as 55 to 65 Percent, (2) Fine finishing by mechanical means gave good results in the view point of fatigue, but surface roughness alone will not be a criterion of surface conditions influencing endurance limits, (3) This study gave further assurance of the results obtained from the previous study on Fatigue.

營農 機械化 作業體系에 關한 調査 硏究

鄭鳳守 진주산업대학교 1977 論文集 Vol.15 No.-

This study was carried out to determine the status of farm machanization which could solue the shortage of farm labour power, and the conventional the medium size mechanizing work to set up the farm mechanization and the work system The results obtained were as follows 1. The amount of various farm machineries were increased rapidly last 10 years(65-75) i.e. power tiller 60 times, farm tractors 28 times, and power sprayers 11 times. 2. The farm working hours were greatly dereased about 34.2% between 2.802 hours per hec, in 1965 and 1844.5 hours per hec, in 1975. The shortage of agricultural labour power according to this decreasing transition could been solved by the supply of main farm machineries. 3. In case of ricefarming, 1,293.7 hours were meeded by the conventional farming, 644.3-748.3 hours by the use of medium size farm machineries, and 255.3-290 hours by the use of large size farm machineries. 4. Generally speaking many working hours were needed in transplanting, havesting, thrashing and preventing works, In the transplanting work, 255.1 hours were needed by the conventional farming, 35∼43 hours i.e, shortness 212-220 hours (6 to 7 times) by use of medium size farm machineries, and 20-26 hours i.e. shortened 229-235 hours (10 to 13 times) by the use of large size farm machineries.

농축산폐기물(農畜産廢棄物)의 퇴비화(堆肥化)에 관한 기초적(基礎的) 연구(硏究)

정봉수,강용태,Jung, Bing Soo,Gang, Young Tae 대한토목학회 1985 대한토목학회논문집 Vol.5 No.2

본(本) 연구(硏究)에서는 농축산(農畜産) 폐기물(廢棄物)인 돈분(豚糞)에 짚, 톱밥, 포장지(包裝紙) 등(等)을 첨가물(添加物)로 혼합(混合)하여 속성(速成) 퇴비화(堆肥化)하는데 중요(重要)한 작용(作用)을 하는 함수율(含水率), 송풍량(送風量), pH, 공극률(孔隙率) C/N 비(比) 등(等)에 대(對)한 최적치(最適値)의 범위(範圍)를 규명(規明)하고자 제작(製作)된 소형(小型) 회분식(回分式) 실험장치(實驗裝置)에 혼합물(混合物)을 투입(投入)한 후(後) 1주간(週間)씩 연속(連續) 호기성분해(好氣性分解) 실험(實驗) 행(行)하였다. 실험결과(實驗結果)에 의(依)하면 만족(滿足)한 퇴비화(堆肥化)가 이루었을 때의 투입시(投入時) 함수율(含水率)은 50~65%이었고, pH는 7~8이었다. 또한, 이 때의 송풍량(送風量)은 $0.7{\sim}2.0l/min{\cdot}kg-vm$ 이었고, 최고(最高) 온도(溫度)는 $70^{\circ}C$에 도달(到達)하였다. 한편, C/N 비(比)가 110 인 톱밥과 102.50 인 포장지(包裝紙)는 속성(速成) 퇴비화(堆肥化)를 이룰 수가 없었으며 가장 적당(適當)한 C/N 비(比)의 범위(範圍)는 60~70 이하(以下)로 나타났다. $CO_2$ 발생량(發生量)의 변화(變化)에 따라 미생물(微生物)의 활동상태(活動狀態)를 알 수 있었고, $45{\sim}53^{\circ}C$ 범위(範圍)에서 $CO_2$ 발생량(發生量)이 65~85 mg/hr-vm 최대(最大)를 이루었다. Pig manure mixed with straw, sawdust, packing paper and chaff was composted in a batch type enclosed composter without regular mixing for 1 week. The maximum decomposition was obtained in the temperature of $70^{\circ}C$ with an initial moisture content of 50 to 65 %, initial pH of 7 to 8, 0.7 to $2.0l/min{\cdot}kg$ per volatile matter of air supplied and C/N ratio of 60 to 70. The maximum carbon dioxide content in the produced gas was 65 to 85 mg/hr-vm at 45 to $53^{\circ}C$.

動力耕耘機의 性能에 關한 硏究

鄭鳳守,周載洪 진주산업대학교 1968 論文集 Vol.2 No.-

This was studied on working efficiency of power tiller (CT-83.N-6). Working power of power tiller(average horse power 6Hp. maximum horse power 8Hp) was operated three times in plow work(depth 15 cm, Cross size 60cm), which was chosen on clay loam field. Resuelt as following. ①The efficiency of power tiller`s was observed 2∼2.5 times to animal power(Cow), and needed 2l of fuel p/h. ②High speed on read was observed 14.6 per hour. ③Gravity position of power tiller is apt to decline where the main clutch was atta-ched, so it needs much attention in operating.

動力噴霧機의 壓力別 撒布狀態와 作業能率 試驗

鄭鳳守 진주산업대학교 1982 論文集 Vol.20 No.-

This experiment was carried out the efficiency of work and optimum scale, that were classified by pressure and dilution rate. The results are summarized as follows; 1. The efficiency of spray by prssure was required 3'45"(2nozzle. 15ks/㎠), 4'58"(4nozzle, 15kg/㎠) and 2'45"(2nozzle, 25kg/㎠), 3'47"(4nozzle, 25kg/㎠) 2. When dilution rate was 1000times, the efficiency of work was the most sutable. 3. The efficiency of work by nozzle of one man per oneday with speed sprayer was 170a(2nozzle), 140a(4nozzle), and optimum scale was 45ha(2nozzle), 34ha(4nozzle). 4. Working efficiency of speed sprayer is about 11∼13times, compare with hand sprayer and lever sprayer.

簡易試驗方法에 依한 벽돌의 實驗的 硏究

鄭鳳守,朴魯奭 진주산업대학교 1970 論文集 Vol.4 No.-

本 試驗은 簡易實驗方法에 依하여 實施하였기 때문에 定確한 結果는 얻기가 어려웠으나 다만 아래의 몇가지만은 規定할 수가 있다고 본다. 1. 簡易試驗方法에 依하여 얻어진 吸水는 浸水後 처음 2∼3日間은 急激하게 增加되었으나 그 以後에는 吸水率이 점차 줄어들어 3日間 平均 吸水率은 0.23%에 不過하였다. 2. 吸水率과 壓縮强度와의 關係를 보면 吸水率이 크면 클수록 壓縮强度는 낮고 吸水率이 적으면 적을수록 壓縮强度는 높다. 3. 以上과 같은 結果를 보면 現場에서 物理的 簡易實驗으로 벽돌의 吸水率의 强度를 試驗할 수가 있으며 이에 따라서 品質의 向上을 期할 수가 있다고 본다. This research has been carried out in order to derive a simplified testing method applicable on bricks that are abailable at ordinary brick manufacturing plants. 1. The absorption rate of bricks as measured in this experiment was rapidly increased during 2∼3days of immersion. After that, it was gradually increased, its daily average being 0.23 percent. 2. According to the standard testing method, it was found that the higher compressive strength the sample have, the lower absorption rate they have. 3. According to the above results,it could be concluded that the simplified testing method is recommendable as a physical test applicable on common bricks at ordinary brick manufacturing plants in order to be helpful to improve the quality of their products.

Marfan syndrome 환자의 척추 측만증 교정을 위한 마취관리

정봉수,임선아,강평희,정연진,박창길,이경혜 乙支病院 1998 乙支醫報 Vol.21 No.1

Cyclone 燒却爐의 Model 開發에 關한 硏究

鄭鳳守 진주산업대학교 농업기술연구소 1995 農業技術硏究所報 Vol.8 No.-

小型 사이크론 燒却爐의 모델 開發을 위한 基礎資料를 얻고자 本 校內에서 發生하는 쓰레기의 組成狀態, 燒却을 통한 熱流動과 溫度分析, 회재飛散, 排氣熱의 에너지화 등에 관한 實驗結果를 要約하면 다음과 같다. 1. 쓰레기 중 廢紙類가 50.25%로서 資源再活用한다면 쓰레기量을 半減시킬 수 있다. 2. 燃燒實 軸을 중심으로 溫度가 높게 나타난 것은 2次空氣의 亂流로 燃燒粒子들의 滯留時間이 길어 燃燒效率이 높기 때문이라 판단하다. 3. 燃燒效率을 높일려면 적절한 燃料空氣의 混合, 燃燒物의 均質化를 考慮해야할 것으로 思廬된다. 4. 희재飛散은 爐內 壓力이 높을수록 많았으며 燃燒物 投入 뒤집기 등의 操作方法에 따라서도 크게 影響을 미친다. The aim of this experiment is to obtain some basic data for the development of a smallsize cyclone incinerator model. The refuse collected in our school was used for the experiment. The composition of the refuse, the heat fiowing and temperature distribution in the process of of combustion, and the potential energy of the fly ash and the exhaust heat were examinned. The results obtained are as follows : 1. Disuse paper was 50.25% of the collected refuse. If the disuse paper could be recycled, the refuse would be reduced by half. 2. The temperature was higher especially around the axsis of the incinerator. It seems that the combustion efficiency is higher around the axis because the retention of the combustion particles is longer owing to the warm current of the 2nd air. 3. It seems that the proper mixture of fuel and air, and the homogeneity of combustibles are the major factor of the combustion efficiency. 4. The higher pressure in the incinerator prodced the more fly ash. The feeding and turning of combustibles also acted on the quantity of fly ash.

직장악성흑색종 4예 보고

정봉수,김진천,유창식,이한일,김창남,공경엽 대한대장항문학회 1997 Annals of Coloproctolgy Vol.13 No.1

H.264/AVC를 위한 선택적 시간축 에러 은닉 방법

정봉수,최웅일,전병우,김명돈,최송인,Jung Bongsoo,Choi Woongil,Jeon Byeungwoo,Kim Myung-Don,Choi Song-In 대한전자공학회 2005 電子工學會論文誌-SP (Signal processing) Vol.42 No.2

본 논문은 H.264/AVC 비디오 비트스트림의 전송 에러 복원에 알맞는 선택적 시간축 에러 은닉 알고리즘을 제안한다. 제안 알고리즘은 손실 매크로블록이 전경인지 배경인지 판단한 결과에 따른 해당 에러 은닉방법을 수행한다. 손실 블록이 배경으로 판단된 경우에는 단순 대체 기법으로 은닉하며, 손실 블록이 전경으로 선택되었을 경우에는 다중 참조영상에서 추정된 블록들의 유사성을 판단하여 추정블록들을 선택적으로 평균하여 은닉을 한다. 제안된 알고리즘은 CDMA2000 (UMTS)망의 무선(air) 인터페이스에서 발생하는 에러 모의실험을 통하여 H.264/AVC의 FMO 부호화에서 H.264/AVC의 테스트 모델상의 에러 은닉 알고리즘보다 평균 1.18dB 성능 향상이 있으며, N-Slice 부호화에서는 평균 0.33dB의 성능 향상을 나타내었다 또한 주관적 화질면에서도 제안된 방법이 다른 에러 은닉 알고리즘보다 우수함을 보인다. In this paper, we propose a new selective temporal error concealment algerian best suited for H.264/AVC. The proposed algorithm performs selective temporal error concealment depending on whether the lost block is at background or foreground. It the corrupted macroblock is decided as at background, then the simple temporal replacement is performed. Also we propose replacing a lost block at foreground with the selective average of respectively estimated blocks from the multiple reference frames. This paper supposes error-corrupted H.264/AVC video bitstreams over CDMA2000 (or UMTS) air interface. It is shown that under Flexible Macroblock Ordering (FMO) coding of H.264/AVC, the proposed algorithm provides PSNR gain up to 1.18dB compared to built-in algorithm in the K264/AVC test model. In addition, the proposed error concealment method has average PSNR improvement of 0.33dB compared with that under N-slice coding mode. The proposed algorithm also provides better subjective video quality than other conventional error concealment algorithms.