• 기술사
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• 제28권3호
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• pp.121-134
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• 1995

본 논문에서는 생산 환경에서 MAP 네트워크에 접속된 여러 단위제어기기의 운영을 지원하기 위한 네트워크 관리 모듈을 설계하여 공정 모델 시스템에서 시범 운영하였다. 설계된 네트워크 모델의 안정성 해석을 위하여 토큰의 사용권의 공정한 배분과 시스템의 동작이 공정상의 특정한 시간 범위 내에 완료되어야 한다. 따라서 본 논문에서는 네트워크의 부하 파라미터로서 데이타 패킷의 크기와 노드의 수의 변화로 선정하여 이에 따른 네트워크 운영을 위한 토큰 로테이션 시간과 대기 시간의 대응된 변화값을 해석하였다. MAP 네트워크의 운영에서 데이타 패킷의 크기를 10바이트에서 100바이트까지 변화시킬 경우, 이에 대응한 토큰 로테이션 시간과 대기 시간의 변화는 주어진 조건하에서 10msec 이하의 값을 가진다. 따라서 프로그래머블 콘트를러 등의 단위 제어기기가 수십 msec 정도의 응답 하한선을 가지고 있으며 데이타 패킷의 크기는 50바이트를 넘지 않으므로 이의 실시간 처리에 충분히 적용 가능함을 알 수 있다.

• 기술사
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• 제19권4호
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• pp.22-29
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• 1986

1) The recipe for tea is to mix tea leaves or tea buds with odorous pharmaceuctial materials, which are boiled and drunk, addition of honey only to that odorous pharmaceutical meterials without adding tea buds to that can be used. 2) Viewed from the part of tea plant the fruit of it accoupies most. The cereal does as much. 3) what we have referred to from the records on this subject are "Guogapylyong" which is of the yuan dynasty and "Jeungbo-Salymkeongje" which is of the Yi dynasty, based on which no trace of pure tea can be found but odorous pharmaceutical kinds of tea only were widely spread. 4) The characteristics of tea are to help make stomach strong, mind cleared, the lungs copious, counteract, and quench thirstiness. The tea help build liver as well as bring about health. 5) As a result of sense test, those kinds of tea were much better than contemporary kinds of teas as far as flovor and sweetness are concerned. Those teas had complex tastes, while teas of to day have simple one. 6) Because the history not so clear before the periods of Unified Sila that the recordings of teas are rare, we can hardly know about tea. Our ancestors really began to drink teas from the period of Unified Sila on. This country turning to the Koryo dynasty, tea drinking manner began to prevail so much that drinking tea became a ceremony. Daring the Yi dynasty it was much camplicated to make and boil the leaf tea. As a result of the previous fact pure tea came to have disappeared and odorous pharmaceutical became prevailent. 7) For value of exploiting Kungjuk tea (ginger tea seasoned with phyllostachy and addition of honeyl) was the highest among many. The worth of developing all the teas among all the beverages was regarded as that high of 51%, while even the tea regarded as worthless obtained 4％ of support, which is the lowest.

• 기술사
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• 제2권6_7호
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• pp.12-23
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• 1969

The purpose of this study is to find out the reasonable amount of evapo-transpiration required for the paddy rice plant during the whole growing season. So, on the basis of the 3year experimental data concerning the evapo-transpiration from 1966 to 1968, the author obtained the following results. 1) The leaf area index in the densely planted plot is generally higher than that in the conventionally planted one during the first half of growing season. So, the coefficient of transpiration in the former plot is some what higher than in the latter, and the coefficient of water surface evaporation under the plant cover has the inverse relation between both plots. 2) It is unreasonable that coefficient of evapo-transpiration is applied to the calculation of the evapo-transpiration requirments of each growing stage, because a certain degree of variation in meteorological factors and in the thickness of the plant growth is involved in it. 3) It is most reasonable that the rate of transpiration and of the water surface evaporation is applied to the calculation of the transpirated amount and evaporated one in each growing stage because it shows almost constant value in spite of any meteorological conditions in so far as the variety of rice, planted density and control of applying fertilizer are same and the disease and blight are negligible. 4) The ratio of the amount of transpiration to the weight of the whole air dried yields has the tendency of decreasing as that of the yields increase, having almost constant value despite the amount of pan evaporation; and the value is about 210 when the weight of root parts is included to that of the yields. 5) Although the required amount of transpiration during the whole growing season can be calculated with the above ratio, fig. 7 showing the relation between the amount of transpiration and the weight of the yields is more reasonable and will be convinient to find it. And the requirements of water surface evaporation during the same season can also be directly found with the weight of air dried straw refering to fig.8.

• 기술사
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• 제16권3호
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• pp.41-53
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• 1983

The Dangri Crushed Stone Quarry is located in Dangridong, Busan City, and around the estuary of the Nagdong River. The quarry is considered to be a very promised one in the urban area from the standpoints of the assessment of the aggregate rank, the environmental impacts and the transportation distance. The crushed stones for aggregate of the quarry marks the higher rank in the gravity, the absorption ratio, the abrasion ratio, and the stability in comparison with the JISA 5005. The basement vibrations of the residential section in the vicinity of the quarry, which are arised by the millisecond blasting at the quarry site using the gelatin dynamites less than 39kg in weight, are measured to assess the vibration nuisance. The values of acceleration and the magnitudes are less than eight gals and O on the Richter scale respectively, the vibration nuisance thus can be ignored in such scales of the experiments. The traffic vibrations of the residential section are slightly susceptible. In the experiments, the traffic vibrations appears to be sensibler to the basement than the explosion vibration. The explosion noises in the experiments are not checked not only on the RION Sound Level Meter but also to our ears. The values of traffic noises also are in the safety values of the noise nuisance. The crush dust suspends in the air toward the upper valley in the opposite side of the residential area because of the influences of the sea breeze and the valley wind in the daytime, and the monsoon and the topographic disposition. the dust nuisance thus would not be remained in problem. The quarry is operated in the daytime only. The traffic dust in the residential area will be reduced by the faultless pavement and the careful driving. The elaborate survey on the ridges and peaks surrounded the quarry is recommended to prevent in advance the accidents of the rock slide. Moreover, it is required to make an advisory committee to develop the industry and to save the techniques. The most important matter is the accomodation between the attitude of the enterprising man for the social responsibility to the public nuisance and the cooperative spirit of the inhabitants for the industry.

• 기술사
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• 제16권3호
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• pp.5-23
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• 1983

On the Seoul Metropolitan Subway Construction of No. 3, 4 Line, the total length is 57 Km and it is now undergoing almost 55％ progress. The working method is classified into Open Cut of 70% and the rest of 30% tunnelling method in the 48 job site. Above tunnelling method is execute by American Steel Support System and the rest of 10 job site carried out by New Austria Tunnelling Method. This paper describes Blasting Standardizations works on the above Tunnelling ' Open Cut Method under big slogan, first safety, second execution. As a superintendent, I strived standardization of works with Better powder, Better Drills ' Better Pattern. Geological structure of Seoul area is composed by Jurassic Granite and also the above rockgroup are over burden by Alluviums as a Unconformity. First of all, I carried out the standard amount of powder and burden through experimental standard blasting by each powder as following Blasting works in the subway construction is surrounding shop Building, under pass the city river and also under pass highest building basement floor. I made allowable Blasting Vibration Value by West-Germany Vornorm DIN 4150, Teil 3 and should measure each blasting works as fellows all of powder is used basically Low-Gravity and Low Velocity such as Slurry, Ammonium Nitrate ' Finex I, II. for Smooth Blasting Instead of Gelatin Dynamite. Electric Detonation Cap is used basically M/S Delay Cup instead of Electric delay ' Simultaneous cap. I applied following formula V=KW3/4 $D^{-2}$ V=Particle Velocity (Cm/sec) K=Ginh Huh's Value W=Delay Charge (Kg) D=Distance(m) In the Open Cut, within 1m distance from H-pile I made to use the Concrete breaker, as following V=7W/$^{0.5}$V/$^{-1.75}$ On the Concentrate Building area, I advise to use Light class drill ø36m Bit and advance 1.1m per round blasting the three boom jumbo drill over ø45mm used only suburb of city.e Light class drill ø36m Bit and advance 1.1m per round blasting the three boom jumbo drill over ø45mm used only suburb of city.

• 기술사
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• 제34권5호
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• pp.82-88
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• 2001

Mackerel(Scomber japonicus), pacific saury (Cololabis saira) and sardine(Sardinops melanosticta) is widely distributed in coastal seawater of Korea, these fishes are not effective utilization as processing material cause by rapid lipid oxidation and off flavour. This study was attempted to lipid distribution in body section, whole body, meat, viscera, skin and head, and fatty acid composition of the oils obtained from these body section. The content of total lipid of mackerel, pacific saury and sardine were 12.48%, 12.79% and 13.81% respectively, and lipid contents in different body section of mackerel was muscle 2.31%, viscera 3.54%, skin 1.43% and head 5.20%, while in cause of sardine was muscle 4.17%, viscera 3.15%, skin 1.72%, and head4.77%. The major saturated fatty acids of mackerel, pacific saury and sardine oil were C$\_$16:0/(palmitic acid), C$\_$18:0/(stearic acid), C$\_$14:0/(myristic acid), and monoenoic acids was C$\_$18:0/(oleic acid), C$\_$16:1/ (palmitolic acid), C$\_$22:0/(erucic acid) and C$\_$20:1/(gadoleic acid), in cause of polyenoic acid was C$\_$22:6/(DHA, docosahexaenoic acid), C$\_$20:0/(EPA, eicosapentaenoic acid), C$\_$22:4/(behenic acid), C$\_$18:2/(linoleic acid) high quantity in order. When fresh oil extracted from mackerel, pacific saury and sardine was stored for 20 days at 5$\^{C}$, carbonyl and acid value of oil increased with storage day, but peroxide value decreased after 15 days.

• 기술사
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• 제37권2호
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• pp.34-36
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• 2004

우리나라의 과학기술은 지난 40여년간 국가 산업발전에 발맞춰 고도성장을 효과적으로 뒷받침, '60-'70년대 모방$.$학습단계 '80년도 내재화단계를 거쳐 '90년대이후 신기술 개발경쟁에 뛰어드는 혁신단계로 진입, 장기간의 과감한 투자로 과학기술역량이 급신장, 연구개발비 '67년 48억\$\longrightarrow$'02년 17조 3,251억원(세계 6위), 연구원수 '68년 5,024명 \$\longrightarrow$'02년 18만 9,888명(세계 9위), 미국내 특허출원 10년간 평균증가율 32%(OECD 국가중 1위) SCI 논문게재수 5년간 평균증가율 15%(세계4위), 그러나 선진국과 비교할 때 양적$.$질적으로 미흡, '02년을 기준으로, 연구개발투자는 미국의 1/20, 일본의 1/10, 독일의 1/3수준에 불과, '01년 기준 상위 20개 기업의 연구개발비 총액은 50억불 정도로, Ford(74억불), GM(62억불)보다 적음, 인구 천명당 연구원 수 (2,98명)도 주요국에 비해 부족 일본 7.07명, 러시아 6.98명, 독일 5.90명, 대만 4.77('01년, IMD), 특히 신성장산업의 창출과 산업의 고도화에 직결되는 핵심원천기술이 취약, SCI 게재논문수는 세계 14위이나, 논문의 질적 수준을 나타내는 피인용도는 세계 31위('02년), 10대 성장동력 10대 산업과 관련되는 핵심기술의 평균 기술수준은 최고 대비 69.8%, 기술격차는 4.2년 - 디지털 TV/방송산업 74.9%/기술격차 3.1년, - 바이오 신약/장기 산업 61.2% 수준, 과학기술 및 과학기술자에 대한 사회적 인식이 낮음, 이공계 출신의 사회 각 분야 지도층 진출비율이 매우 낮음(16대 국회의원 8%, 3급이상 국가공무원중 기술직 비율 17.1% 등), - 민간의 경우, 10대 기업 임원의 53%가 이공계 출신, 100대 기업 CEO의 38.4%가 이공계 출신, 대입수능시험에서 자연계 지원비율이 감소 -40.1%('99)\$\longrightarrow$34.7%('00)\$\longrightarrow$29.4%('01)\$\longrightarrow$26.9%('02)\$\longrightarrow$30.3%('03)\$\longrightarrow$31.5%\$\longrightarrow$'04)

• 기술사
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• 제1권1호
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• pp.18-25
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• 1968

Higher yield in rice paddies is greatly dependent on adequately balanced and timely supply of water. A majority of rice paddy in Korea is generally irrigated by rainfall, but in many cases it has to be supplemented by artificial irrigation for optimum rice culture. Although the water requirement of rice plant is for higher Than that of athec crops, submerged condition of rice paddy is not Necessarily required. The moisture requirement of rice plant varies with its growing stages, and it is possible to increase the irrigation efficiency through reduction of water loss due to percolation in rice paddies. An experimental plots were set up by means of sandomized block design with three duplication; (a) All time submerged, (b) Economically controlled, and (c) Extremely controlled. Three different irrigation periods Were (a) Initial sage, (b) Inter-stage, and (c) Yast stage. The topsoil of the three plots were excavated to the depth of 30 cm and then compacted with clay of 6 cm thickness. There after, they were piled up with the excavated top soils, leveled and cored with clay of 6 cm thickness around footpath in order to prevent leakage. The results obtained from the experiments are as follows, 1. There is no difference among the three experiments plots in terms of physical and chemical conditions, soil properties, and other characteristics. 2. Culm length and ear length are not affected by different irrigation methods. 3. There is no difference in the mature rate and 1, 000 grain weight of rice for the three plots. 4. The control plot which was irrigated every three days shows an increased yield over the all the time submerged plot by 17.8 percent. 5. The clay lined plot whose water holding capacity was held 5 days long, needs only to be irrigated every 7 days. 6. The clay lined plot shows an increased yield over the untreated plot ; over all-the-time submerged plot by 18 percent ; extremely controlled plot by 18 percent, and economically controlled plot by 33 percent. 7. It may be saved in water requirement about one Thirds.

• 기술사
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• 제28권5호
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• pp.12-19
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• 1995

한국산 구약 감자(elephant-foot=Amorphoph-alus Konjak K.Koch)의 이화학적 성분 조성을 조사하기 위하여 국산 생감자와 분말을 시료로 하여 외국산 정분과 같이 분석한 결과 생감자는 수분이 80.64%였고 고형분의 대부분은 당류, 단백질, 희분이고 섬유나 지방은 미량 존재하였다. 건조 분말 정제품인 정분은 당류 74.42-80.41%, 수분은 10% 전후였고 만난 함량은 한국산이 일본, 중국산보다 상당히 적었고 역시 가용성 유리당도 일본산이 높고 한국산이 낮았는데 구성당은 한국산은 Sucrose가 많은 대신 외국산은 Fructose, Glu-cose 함량이 높았다. 한국산 정분의 단백질 함량은 외국산보다 2배 많았고 이의 amino acid 조성은 Glutamic acid, Aspartic acid, Arginine 등이 총아미노산의 45%를 차지하고 Valine, Serine, Leucines, Glycine의 순서로 많았다. 정분의 무기물은 K가 많고 P>Na>Ca순으로 많게 함유하였고 chip의 정분 수율은 한국산이 61%, 중국산은 57.6%였으며 정분의 백도는 색도 측정치는 중국산이 약간 높았으나 육안으로는 별 차이가 없이 비슷하였다.

• 공학교육연구
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• 제21권3호
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• pp.56-65
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• 2018

With rapid advance of technologies including information and communication technologies, jobs are evolving faster than ever. Architectural engineering is no exception in this regard, and the green architectural engineering is emerging fast as a promising new field. In this study, a Delphi study of expert architectural engineers are conducted to find out (1) near future prospects of the field, (2) near future emerging jobs, (3) competencies needed for these jobs, and (4) educational content necessary to build these competencies with regards to the green architectural engineering. Initial Delphi survey consisting of open-ended questions in the above four areas were conducted and came out with 65 items after duplicate removal and semantic refinements. Further refinements via second and third wave of Delphi results into 40 items that the 13 architectural engineering experts may largely agree upon as future prospects with regards to the green architectural engineering. Findings indicate that it is expected that the demand for green architectural engineering and needs for automatic energy control system increase. Also, collaborations with other fields is becoming more and more important in green architectural engineering. The professional work management skills such as knowledge convergence, problem solving, collaboration skills, and creativity linking components from various related areas seem to also be on the increasing need. Near future ready critical skills are found to be the building environment control techniques (thermal, light, sound, and air), the data processing techniques like data mining, energy monitoring, and the control and utilization of environmental analysis software. Experts also agree on new curriculum for green building architecture to be developed with more of converging subjects across disciplines for future ready professional skills and experiences. Major topics to be covered in the near future includes building environment studies, building energy management, energy reduction systems, indoor air quality, global environment and natural phenomena, and machinery and electrical facility. Architectural engineering community should be concerned with building up the competencies identified in this Delphi preparing for fast advancing future.