• 한국산업보건학회지
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• 제16권3호
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• pp.254-263
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• 2006

Manganese has a role as both toxic and essential in humans. Manganese is also an essential component in the welding because it increases the hardness and strength, prevents steel from cracking of welding part and acts as a deoxidizing agent to form a stable weld. In this study, manganese generation rate and its content was determined in flux cored arc welding on stainless steel. Domestic two products and foreign four products of flux cored wires were tested in the well designed fume generation chamber as a function of input power. Welding fume was measured by gravimetric method and metal manganese was determined by inductively coupled plasma-atomic emission spectrophotometer. The outer shell of the flux cored wire tube and inner flux were analyzed by scanning electron microscopy to determine their metal compositions. Manganese generation rate($FGR_{mn}$) was increased as the input power increased. It was 16.3 mg/min at the low input power, 38.1 mg/min at the optimal input power, and up to 55.4 mg/min at the high input power. This means that $FGR_{mn}$ is increased at the work place if welder raise the current and/or voltage for the high productivity. The slope coefficient of $FGR_{mn}$ was smaller than that of the generation rate of total fume(FGR). Also, the correlation coefficient of $FGR_{mn}$ was 0.65 whereas that of FGR is 0.91. $FGR_{mn}$ was equal or higher in the domestic products than that of the foreign products although FGR was similar. From the electron microscopic analytical data, we concluded that outer shell of the wire was composed mainly of iron, chromium, nickel and less than 1.2 % of manganese. There are many metal ingredients such as iron, silica, manganese, zirconium, titanium, nickel, potassium, and aluminum in the inner flux but they were not homogeneous. It was found that both $FGR_{mn}$ and content of manganese was higher and more varied in domestic flux cored wires than those of foreign products. To reduce worker exposure to fumes and hazardous component at the source, further research is needed to develop new welding filler materials that improve the quality of flux cored wire in respect to these points. Welder should keep in mind that the FGR, $FGR_{mn}$ and probably the generation rate of other hazardous metals were increased as the input power increase for the high productivity.

• 한국버섯학회지
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• 제18권4호
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• pp.387-392
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• 2020

국내 유통 중인 건조 목이 8건(국내산 3건, 중국산 5건)을 수집하여 잔류농약 321종, 중금속 7종, 방사능 3종의 유해물질 잔류성분을 조사하였다. 잔류농약 검사결과 국내산 3건에서는 검출되지 않았으나, 중국산 5건 중 4건에서 Chlorpyrifos, Isoprocarb, Mepiquat chloride, Carbendazim이 검출되었다. 농산물 농약 잔류허용기준에 의하면 목이는 Mepiquat chloride(0.5 mg/kg 이하)만 기준치가 설정되어 있다. 또한 중금속 검사결과는 모든 건조 목이에서 미량의 중금속이 검출되었으나, 기준치 이하로 낮게 나타났다. 다만 국내산 시료 1건에서 납 함량이 기준치(0.3 mg/kg)보다 높게 나타나 정확한 원인 규명을 위해서는 톱밥배지, 지하수, 보관·유통 과정에 대한 추가적인 조사가 필요할 것으로 보여진다. 방사능 조사결과에서는 모든 건조 목이에서 방사능 농도가 MDA값 이하로 불검출 수준으로 나타났다. 국내산과 중국산의 평균 방사능 농도는 요오드(131I)와 세슘(134Cs)은 비슷한 수준으로 나타났으며, 세슘(137Cs)은 국내산보다 중국산에서 다소 높게 나타났다. 방사성 세슘(137Cs)은 버섯류에 잘 농축되는 것으로 알려져 있는데 이번 조사에서는 국내 유통 중인 건조 목이는 방사능에 안전하게 나타났다.

• 한국수학교육학회지시리즈A:수학교육
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• 제44권3호
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• pp.457-475
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• 2005

We have inquired on what the statistical classes of the secondary schools had been aiming to, say the epistermlogical objects. And we now appreciate that the main obstacle to the systematic articulation is the lack of anticipation on what the statistical concepts are. This study focuses on the ingredients of the statistical concepts. Those are to be the ground of the systematic articulation of statistic courses, especially of the one for the school kids. Thus we required that those ingredients must satisfy the followings. i) directly related to the contents of statistics ii) psychologically developing iii) mutually exclusive each other as much as possible iv) exhaustive enough to cover all statistical concepts We examined what and how statisticians had been doing and the various previous views on these. After all we suggest the following three concepts are the core of conceptual developments of statistic, say the concept of distributions, the summarizing ability and the concept of samples. By the concepts of distributions we mean the frequency views on each random categories and that is developing from the count through the probability along ages. Summarizing ability is another important resources to embed his probe with the data set. It is not only viewed as a number but also to be anticipated as one reflecting a random phenomena. Inductive generalization is one of the most hazardous thing. Statistical induction is a scientific way of challenging this and this starts from distinguishing the chance with the inevitable consequences. One's inductive logic grows up along with one's deductive arguments, nevertheless they are different. The concept of samples reflects' one's view on the sample data and the way of compounding one's logic with the data within one's hypothesis. With these three in mind we observed Korean Statistic Curriculum from K to 12. Distributional concepts are dealt with throughout but not sequenced well. The way of summarization has been introduced in the 1 st, 5th, 7th and the 10th grade as a numerical value only. One activity on the concept of sample is given at the 6th grade. And it jumps into the statistical reasoning at the selective courses of ' Mathematics I ' or of ' Probability and Statistics ' in the grades of 11-12. We want to suggest further studies on the developing stages of these three conceptual features so as to obtain a firm basis of successive statistical articulation.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.438-444
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• 2015

본 연구는 발효유류의 HACCP(Hazard Analysis Critical Control Point)시스템 적용을 위한 목적으로 하였다. 발효유류의 주원료, 작업장 시설과 작업자 등에 대하여, 2013년 11월 5일~2014년 4월 13일까지 충청남도 천안시 서북구 소재에 있는 YD 업체에서 제공받았다. 제조공정도는 일반적인 발효유류 제조업체의 제조공정을 참고로 작성하였다. 제조공정도는 원료(원유, 액상과당, 올리고당, 유산균), 부재료, 포장재의 입고, 보관, 투입, 예열, 혼합, 균질, 살균, 예냉, 배양, 냉각, 여과, 내포장, 외포장, 보관 및 출하공정으로 Fig. 1과 같이 작성하였다. 원료의 미생물학적위해요소 분석결과는 Table 1과 같다. 본 연구결과 발효유의 원재료와 살균($90^{\circ}C{\pm}5^{\circ}C$에서 $35{\pm}3$분) 후에는 위해미생물검사 결과는 안전하나 제조환경과 작업자의 미생물검사 결과 체계적인 세척 및 소독을 실시하여 미생물학적 위해를 감소시키고, 작업자 위생교육 등을 통하여 개인위생개념 향상과 작업장 내 공기중의 미생물 관리가 함께 이루어져야 할 것으로 여겨진다.

• 약학회지
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• 제53권5호
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• pp.274-280
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• 2009

To survey the status of quality control of major ingredients of 'Ssanghwatang (Oriental medicine used for fatigue)', we analyzed 1,024 samples (9 kinds) of medical herbs to determine amounts of ashes, acid-insoluble ashes, loss on drying that are major elements to ensure basic quality of herbal drugstuffs. After ash analysis, Paeoniae Radix (from China) failed to meet the herbal standard criterion. After yielding Z-score(indicating the probability of exceeding its criterion) Zizyphi Fructus, Zingiberis Rhizoma, Paeoniae Radix, Rehmanniae Radix Preparata became objects of intense quality control (=IQC). Analysis on loss on drying shows Cinnamomi Cortex was unsuitable and was put under the IQC. In case of respective heavy metals, Angelicae Gigantis Radix, Cnidii Rhizoma, Cinnamomi Cortex exceeded the maximum permissible range for Cd. The 3 kinds of sub-standards were put to the IQC. Statistic figures showed a significant correlation (t-test, p<0.01) between country-of-origin and sub-quality rates. Compared to domestic one, imported medicinal herbs were less suitable in regard of acid-insoluble ash, loss on drying and Pb/Hg content. Meanwhile, amounts of Acid-insoluble ash showed positive relation with amounts of Pb (r=0.202) and As (r=0.243) among heavy metals leading to an inference that herbs of which root/rhizome is used for medical purposes attribute its high heavy metal content to the fine earth/sand being stuck to its root stalk.

• 한국산학기술학회논문지
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• 제14권11호
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• pp.5792-5799
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• 2013

본 연구는 떡류의 HACCP(Hazard Analysis Critical Control Point)시스템 적용을 위한 목적으로 하였다. 떡의 주원료, 작업장 시설과 작업자 등에 대하여, 2012년 9월 12일~2013년 2월 13일까지 서울시 용산구 서계동 소재에 있는 KB 업체에서 제공받았다. 제조공정도는 일반적인 떡류 제조업체의 제조공정을 참고로 작성하였다. 제조공정도는 원료 농산물(맵쌀, 찹쌀, 팥 등), 부재료, 용수와 포장재료의 입고, 보관, 계량, 세척, 불림, 분쇄, 체선별, 혼합, 시루작업, 증자, 내포장, 금속검출, 외포장, 보관 및 출하공정으로 Fig. 1과 같이 작성하였다. 원료농산물의 미생물학적 위해요소 분석결과는 Table 1과 같다. 본 연구결과 떡의 원재료와 제품의 위해미생물검사 결과는 안전하나 제조환경과 작업자의 미생물검사 결과 체계적인 세척 및 소독을 실시하여 미생물학적 위해를 감소시키고 작업자 위생교육 등을 통하여 개인위생개념 향상과 작업장 내 공기중의 미생물 관리가 함께 이루어져야 할 것으로 여겨진다.

• 한국산업보건학회지
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• 제28권1호
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• pp.91-99
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• 2018

Objectives: From a policy perspective, the introduction of confidential information reviews is a vital task for expanding workers' right to know and improving hazardous materials information communication. In this study, rational methods for introducing and administering confidential information reviews were examined as a part of advancing chemical information communication. Methods: The domestic status, social demands, and control cases from other countries about confidential information in material safety data sheets(MSDSs) were all examined. Additionally, principles for introducing MSDS confidential information review, what needs to be revised prior to its introduction, and procedures and manners of reviewing confidential information were suggested. Results and Conclusions: When composition information on MSDS needs to be protected in the EU and Canada, confidential information should be claimed and then approved by competent authorities with a principle of reviewing confidential information prior to rescinding information from MSDS. Applying the same principle, certain information on an MSDS that needs to be protected should be reviewed and approved in Korea. As a result, the MSDS is communicated with approval numbers replacing composition information. MSDS confidential information review has five steps, including deciding whether chemicals claimed to be confidential are excluded from applying for a confidentiality exemption, the names and concentration ranges of ingredients are adequate, and the claimed information is valid in terms of confidentiality.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.73-81
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• 2018

The giant mealworm beetle, Zophobas atratus (Coleoptera: Tenebrionidae), is a tropical beetle. As this beetle can be used as an ingredient in animal feed, the effects of brewer's spent grain (BSG) on the development and nutritional value of Z. atratus were investigated. As results, there were no significant differences on the larval survival rate, body weight, and duration at different content of BSG, mixed with conventional feed, wheat bran (WB). Based on these results, BSG can be mixed with wheat bran as a Z. atratus food ingredient without any problems. The nutritional value was compared between 100% wheat bran control and 50% BSG experimental groups. The moisture, crude protein, carbohydrates, and amino acids were 1.1-1.4 times higher in the 50% BSG group. In the BSG group, the linoleic acid content was 1.6 times higher than that in the control group. In the wheat bran group, the oleic acid content was 38.4%, which was 1.3 times higher than that in the BSG group. As minerals, the control and BSG groups showed high potassium and phosphorus contents. In terms of hazardous materials, four heavy metals (lead, mercury, arsenic, and cadmium) and two microorganisms (Escherichia coli and Salmonella spp.) were not detected. There were no significant differences in developmental characteristics between the wheat bran and BSG mixed groups, and the nutritional values were better in the BSG mixed group. Therefore, BSG can be used as alternative food source for rearing Z. atratus.

• 동의생리병리학회지
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• 제34권5호
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• pp.215-221
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• 2020

Adulterated herbal medicine is intentionally added with undeclared improper or inferior ingredients which should not be in herbal medicine. The contamination with potentially hazardous substances such as heavy metal, pesticides, fungus, and microorganism sometimes can be regarded as one of adulteration in a broad sense. The problem of adulteration is that adulterated herbal medicine shows poor quality and/or can cause adverse events. Therefore, it is important to control adulteration issues for quality assurance and qualitative improvement of herbal medicines. This study aims to summarize and make a reference how to control adulterated herbal medicine. In this process, this study is to investigate studies about adulterated herbal medicine via searching Korean and foreign electronic databases such as PubMed, NDSL and OASIS. Finally eighteen papers were included to this study and analyzed according to the type of study, the category and efficacy of adulterants, the type of analysis methodologies and possible adverse events of adulterants. Phosphodiesterase type 5 (PDE-5) inhibitors for male sexual enhancement and anorexic, laxative, diuretic agents for weight loss and treating obesity has been used frequently as adulterants. The range of adverse event caused by adulterated herbal medicine were very wide from mild symptoms such as diarrhea, constipation, dizziness and blurred vision to very severe symptoms such as heart failure, hypoglycemia and renal impairment. This study showed the recent trend on the research of adulterated herbal medicine and this will be the ground to develop more detailed systems to control adulterated herbal medicine.

• 융합정보논문지
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• 제11권4호
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• pp.186-193
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• 2021

유령멍게와 노랑꼭지유령멍게는 국내의 경우, 항만, 선박의 바닥, 양식장에 대량으로 발생하여 큰 피해를 입혀, 위해종으로 지정되어 있다. 따라서 이들을 이용하는 측면에서 화장품 원료로의 사용 가능성을 검토하였다. 유령멍게와 노랑꼭지유령멍게를 70% 에탄올로 추출물을 제조하여 항산화능을 측성하였다. 유령멍게와 노랑꼭지유령멍게 추출물 20 mg/mL에서 DPPH는 각각 71.80%, 21.40%를 보였고, ABTS는 각각 95.47%, 27.53%, nitric oxide 생성 억제능은 각각 97.47%, 88.90%로 나타났다. 총 페놀 함량은 유령멍게와 노랑꼭지유령멍게에서 각각 0.081, 0.041 mg gallic acid/mg extract으로 나타났다. 결과적으로 노랑꼭지유령멍게보다 유령멍게에서 다소 높은 항산화능을 보였다. 이들은 추출물은 동물성 유래 항산화물질들로 화장품 소재로서 활용 가능함을 확인하였다.