• Title/Summary/Keyword: Substance Use

Search Result 461, Processing Time 0.028 seconds

A Study on F. L. Wright's Interpretation of the Space and the Method of the Composition in his architectural works (Frank Lloyd Wright의 건축작품에 나타난 라이트의 공간 해석과 구성방법에 관한 연구(硏究))

  • Oh, Zhang-Huan;Lee, Kang-Up
    • Journal of architectural history
    • /
    • v.7 no.4 s.17
    • /
    • pp.29-47
    • /
    • 1998
  • The aim of this study is to understand the original methods of architectural composition in F. L. Wright's works, For this purpose, the principal thoughts based on his organic architecture was examined over all others, and the results of this study are as follows. 1. F. L. Wright knew Taoist Philosophy, especially Lao-tzu's thought about space based on traditional oriental arts included traditional japanese arts by his superior intuition. this is similar to Froebel Thought in the principal theory, that is, his own unique field of abstract architectural education with three-dimensional geometry learned through Froebel Gifts. 2. Space is reality ; such Lao-tzu's thought, reversed the sense of values, influenced F. L. Wright's way to accomplish his own continuous space. that is to say, he attempted taking precedence of spatial organization by the unit of three-dimensional module made the substance, Froebel Blocks (3, 4, 5, 6 Gifts) into non-substance, and trying to do the methods of continuous liberal composition in architecture. which is his original accomplishment, namely his mentioned 'democratic' because of judging the space and the mold of architecture as individualities. 3. F. L. Wright treated the space as a positive entity, so that he created his own architecture organically combined with spaces and forms. : This was the result that he comprehended both formative, physical worth in West and spatial, non-physical worth in East as equivalence. It is understood that F. L. Wright's works combined with East and West are the significance of his architecture and the progress of true internationalities and modernization in modern architecture. 4. From the analyses of his works, we knew the fact that F. L. Wright's architecture, especially in the spatial organization were performed by the reasonable methods with geometric system of Froebel Gifts. In the observation of our fundamental way of thinking on his architecture, this study shows the necessity to let us get out of preconceptions and conclusions that the organic architecture is mysterious and difficult, but to systematize and put his organic methods to practical use.

  • PDF

Record Keeping of Employee Exposure to Chemical Hazards under Industrial Safety and Health Law (근로자의 화학물질 노출관련 기록 보존에 관한 연구)

  • Oh, Sangmin;Park, Donguk;Yu, SeoungJae;Jung, Jin Woo;Lim, KyungTaek;Lee, Jaehwan;Ha, Kwonchul
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.23 no.4
    • /
    • pp.367-373
    • /
    • 2013
  • Objectives: Employee exposure record refers to a record containing information about environmental (workplace) monitoring or measuring of a toxic substance or harmful physical agent. The aims of this study were to examine problems related to exposure records and provide some amendments to the Korean Industrial Safety & Health Act for the effective management of chemical substances under the law. Methods: This study performed a literature search and review on legal provisions related to exposure records of a number of different countries, including Korea, the USA, Japan, EU, Germany, and the UK. They were compared and investigated and the amendment of articles was suggested. Results: The results of this study were provided as suggested amendments to the related act. There were a variety of ways of improvement, including a 30-year retention period and the introduction of new access methods, contents, transfer, and maintenance methods. All exposure data elements have to be standardized, including reference to a similar exposure group (SEG), sampling strategy, and circumstances of exposure (e.g., date, shift length, use of personal protective equipment, etc.). The SEGs are described by process, job, task, and environmental agent. Conclusions: This study is expected to provide for the amendment of the related act in order to ensure effective management of exposure records and is helpful for solving the cause and result of occupational disease by keeping exposure records according to the Industrial Safety & Health Act.

Remediation of heavy metal-contaminated soils using eco-friendly nano-scale chelators

  • Lim, Heejun;Park, Sungyoon;Yang, Jun Won;Cho, Wooyoun;Lim, Yejee;Park, Young Goo;Kwon, Dohyeong;Kim, Han S.
    • Membrane and Water Treatment
    • /
    • v.9 no.3
    • /
    • pp.137-146
    • /
    • 2018
  • Soil washing is one of the most frequently used remediation technologies for heavy metal-contaminated soils. Inorganic and organic acids and chelating agents that can enhance the removal of heavy metals from contaminated soils have been employed as soil washing agents. However, the toxicity, low removal efficiency and high cost of these chemicals limit their use. Given that humic substance (HS) can effectively chelate heavy metals, the development of an eco-friendly, performance-efficient and cost-effective soil washing agent using a nano-scale chelator composed of HS was examined in this study. Copper (Cu) and lead (Pb) were selected as target heavy metals. In soil washing experiments, HS concentration, pH, soil:washing solution ratio and extraction time were evaluated with regard to washing efficiency and the chelation effect. The highest removal rates by soil washing (69% for Cu and 56% for Pb) were achieved at an HS concentration of 1,000 mg/L and soil:washing solution ratio of 1:25. Washing with HS was found to be effective when the pH value was higher than 8, which can be attributed to the increased chelation effect between HS and heavy metals at the high pH range. In contrast, the washing efficiency decreased markedly in the low pH range due to HS precipitation. The chelation capacities for Cu and Pb in the aqueous phase were determined to be 0.547mmol-Cu/g-HS and 0.192mmol-Pb/g-HS, respectively.

The effect of working parameters on removal of casting gold alloy using a piezoelectric ultrasonic scaler with scaler tip in vitro (압전방식 초음파 치석제거기의 작업조건에 따른 치과주조용 합금의 삭제에 관한 연구)

  • Cha, Kuk-Bong;Kim, Won-Kyung;Lee, Young-Kyoo;Kim, Young-Sung
    • Journal of Periodontal and Implant Science
    • /
    • v.39 no.2
    • /
    • pp.139-148
    • /
    • 2009
  • Purpose: Ultrasonic scalers have been widely used for removing biofilm which is considered as major etiologic factor of periodontal disease. The purpose of this study was to evaluate the effect of working parameters of piezoeletric ultrasonic scaler with scaler tip (No. 1 tip) on casting gold alloy removal. Methods: Type III dental casting gold alloy (Firmilay$^{circledR}$, Jelenko Inc, CA, USA) was used as substitute for tooth substance. Piezoeletric ultrasonic scaler and No.1 scaler tip (P-Max$^{circledR}$, Satelec, France) were selected. The selected working parameters were mode (P mode, S mode), power setting (2, 4, 8) and lateral force (0.5 N, 1.0 N, 2.0 N). The effect of working parameters was evaluated in terms of ablation depth, ablation width and ablation area. Results: Mode influenced ablation depth and ablation area. Power also influenced ablation depth and ablation area. Especially, Power 2 and power 8 showed statistically significant difference. Lateral force had influence on ablation width, and 0.5 N resulted significant increase compared with 1.0 N and 2.0 N. Ablation depth was influenced by mode, power and lateral force and defect width was influenced by lateral force. Ablation area was influenced by mode and power. Conclusions: It can be concluded that the use of piezoelectric ultrasonic scaler with No. 1 scaler tip in S mode and high power may result in significant loss of tooth substance.

Studies on the aqueous ammonia alternatives in the wet scrubbing method (습식 세정법에서 암모니아 대체물질에 관한 연구)

  • Kim, Jae Gang;Lee, Ju-Yeol;Park, Byung Hyun;Choi, Jin Sik
    • Journal of the Korean Applied Science and Technology
    • /
    • v.33 no.1
    • /
    • pp.110-117
    • /
    • 2016
  • In the existing research, the ammonia aqueous solution was used in order to remove the Nitrogen dioxide using the scrubber. However, ammonia is poisonous and stench is extreme. So, the system application follows the difficulty. Experiments were conducted to find a substitute material ammonia. The sodium hydroxide(NaOH), sodium thiosulfate ($Na_2S_2O_3$), and urea were used with the substitute substance. The experimental condition proceeded as the optimum conditions in the existing ammonia use. The experimental result NaOH and $Na_2S_2O_3$ was available. NaOH showed the efficiency which is the highest in 2.5%. And $Na_2S_2O_3$ showed the efficiency which is the highest in 5.0%. The efficiency was not fixed and the urea was inappropriate with the substitute substance.

The Effect of Dimethyl Dimethoxy Biphenyl Dicarboxylate (DDB) against Tamoxifen-induced Liver Injury in Rats: DDB Use Is Curative or Protective

  • El-Beshbishy, Hesham A.
    • BMB Reports
    • /
    • v.38 no.3
    • /
    • pp.300-306
    • /
    • 2005
  • Tamoxifen citrate is an anti-estrogenic drug used for the treatment of breast cancer. It showed a degree of hepatic carcinogenesis, when it used for long term as it can decrease the hexose monophosphate shunt and thereby increasing the incidence of oxidative stress in liver rat cells leading to liver injury. In this study, a model of liver injury in female rats was done by intraperitoneal injection of tamoxifen in a dose of 45 mg/kg body weight for 7 successive days. This model produced a state of oxidative stress accompanied with liver injury as noticed by significant declines in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant elevations in TBARS (thiobarbituric acid reactive substance) and liver transaminases; sGPT (serum glutamate pyruvate transaminase) and sGOT (serum glutamate oxaloacetate transaminase) levels. The oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) in a dose of 200 mg/kg body weight daily for 10 successive days, resulted in alleviation of the oxidative stress status of tamoxifen-intoxicated liver injury in rats as observed by significant increments in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases; sGPT and sGOT levels. The administration of DDB before tamoxifen intoxication (as protection) is more little effective than its curative effect against tamoxifen-induced liver injury. The data obtained from this study speculated that DDB can mediate its biochemical effects through the enhancement of the antioxidant enzyme activities and reduced glutathione level as well as decreasing lipid peroxides.

Prediction of Photo-Carcinogenicity from Photo-Ames Assay (Photo-Ames Assay를 이용한 광발암성 예측)

  • Hong Mi Young;Kim Ji Young;Chung Moon Koo;Lee Michael
    • Environmental Mutagens and Carcinogens
    • /
    • v.25 no.1
    • /
    • pp.6-12
    • /
    • 2005
  • Many compounds might become activated after absorption of UV light energy. In some cases, the resulting molecule may undergo further biological reaction of toxicological relevance related especially to the photo-carcinogenicity resulting from photo-genotoxicity. However, no regulatory requirements have been issued with the exception of guideline issued by the Scientific Committee of Cosmetology, Commission of the European Communities (SCC/EEC) on the testing of sunscreens for their photo-genotoxicity. Thus, the objectives of this study are to investigate the utility of photo-Ames assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-Ames assay was performed on five test substances that demonstrated positive results in photo-carcinogenicity tests: 8-methoxypsoralen (photoactive substance that forms DNA adducts in the presence of ultraviolet A irradiation), chlorpromazine (an aliphatic phenothiazine an a-adr-energic blocking agent), lomefloxacin (an antibiotic in a class of drugs called fluoroquinolones), anthracene (a tricyclic aromatic hydrocarbon a basic substance for production of anthraquinone, dyes, pigments, insecticides, wood preservatives and coating materials) and retinoic acid (a retinoid compound closely related to vitamin A). Out of 5 test substances, 3 showed a positive outcome in photo-Ames assay. With this limited data set, an investigation into the predictive value of this photo-Ames test for determining the photo-carcinogenicity showed that photo-Ames assay has relatively low sensitivity (the ability of a test to predict carcinogenicity). Thus, to determine the use of in vitro genotoxicity tests for prediction of carcinogenicity,' several standard photo-genotoxicity assays should be compared for their suitability in detecting photo-genotoxic compounds.

  • PDF

Object Tracking System for Additional Service Providing under Interactive Broadcasting Environment (대화형 방송 환경에서 부가서비스 제공을 위한 객체 추적 시스템)

  • Ahn, Jun-Han;Byun, Hye-Ran
    • Journal of KIISE:Information Networking
    • /
    • v.29 no.1
    • /
    • pp.97-107
    • /
    • 2002
  • In general, under interactive broadcasting environment, user finds additional service using top-down menu. However, user can't know that additional service provides information until retrieval has finished and top-down menu requires multi-level retrieval. This paper proposes the new method for additional service providing not using top-down menu but using object selection. For the purpose of this method, the movie of a MPEG should be synchronized with the object information(position, size, shape) and object tracking technique is required. Synchronization technique uses the Directshow provided by the Microsoft. Object tracking techniques use a motion-based tracking and a model-based tracking together. We divide object into two parts. One is face and the other is substance. Face tracking uses model-based tracking and Substance uses motion-based tracking base on the block matching algorithm. To improve precise tracking, motion-based tracking apply the temporal prediction search algorithm and model-based tracking apply the face model which merge ellipse model and color model.

COMPARISON OF SHAPING ABILITY OF NICKEL-TITANIUM ROTARY FILES WITH DIFFERENT TAPER IN SIMULATED RESIN CANALS (모형레진 근관에서 엔진 구동용 니켈-타이타늄 파일의 경사도의 차이에 따른 근관성형력의 비교)

  • Kum, Kee-Yeon;Lim, Kyoung-Ran;Jung, Il-Young;Lee, Sung-Jong;Lee, Chan-Young
    • Restorative Dentistry and Endodontics
    • /
    • v.25 no.1
    • /
    • pp.78-84
    • /
    • 2000
  • The aim of this study was to compare shaping ability of nickel-titanium rotary files with different taper in simulated resin canals. The instruments used in this study were GT with .04 taper ProFile with ISO-sized tip, .04 taper ProFile with ISO-sized tip alone, and .02 taper Naviflex file and all canals were prepared by crown-down technique. A total of 30 composite images were made from pre- and post-canal scanned images using Scanjet 4C scanner and Corel photopaint 8.0 and then, prevalence of canal aberrations was measured. The amount of coronal substance the instruments removed was also calculated two-dimensionally on digitized images with the Brain C software to compare the relative enlarging efficiency. Finally, the prepared internal canal form was evaluated three-dimensionally with impression technique. The results were as follows; 1. The incidence of zipping in Naviflex group was significantly high compared to the other two groups(P<.05). 2. The amount of coronal substance the GT combined group removed was significantly larger than the other two groups(P<.05). 3. The GT combined group produced canals with good taper and flow. Under the conditionas of this study, the combined use of larger tapered nickel-titanium rotary files prepared simulated canals safely, efficiently and with good three-dimensional form.

  • PDF

Understanding Imminent & Substantial Endangerment (ISE) in the U.S. Environmental Laws and Analysis on ISE Uses (미국 환경법의 Imminent & Substantial Endangerment에 대한 이해 및 사례별 분석)

  • Jeong, Seung-Woo
    • Journal of Soil and Groundwater Environment
    • /
    • v.14 no.3
    • /
    • pp.14-21
    • /
    • 2009
  • This study discusses the definition, determination and use of Imminent & Substantial Endangerment (ISE) included in the United States environmental laws. ISE is a contamination situation and statutory authority that state and federal governments issue an administrative order to responsible parties for clean-up. ISE is appeared in all kinds of official government documents such as administrative oders on consent, judicial consent degrees, and unilateral administrative order. In order to invoke ISE authority, the governments should have evidence of each of the following elements; 1) a possible ISE 2) because of actual or threatened release 3) of a hazardous substance 4) from a facility. The determination of ISE relies on detail scientific evidence and documentation in order to demonstrate the existence of conditions that may present an ISE. However, any official protocol or procedure has not been found for determining an ISE, although an ISE order documentation format is suggested by U.S. EPA.