• Journal of Korean Society of Transportation
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• v.19 no.1
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• pp.17-28
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• 2001

The purpose of this study is to analyze logistics cost of transportation systems on EC(electronic commerce) between company and consumer. Transportation system in logistics is classified by three types on EC. The first type is the direct delivery from supply factory to consumers(type I). The second type is the delivery through distribution center in each area by owner logistics company (type II). The third type is the commission of delivery to the third party logistics company(type III). The logistics of EC has various service characteristics such as dealing with small quantity, various goods, and high frequency. This study assumes that all day's order is delivered on a next day. The logistics cost function is calculated according to the number of orders, delivery distance, transport quantify. and allocated freight trucks for daily order of the subject zone. The logistics cost changes according to the daily order characteristics. Therefore it is simulated to analyze the logistics cost change that considers the type of transportation's order characteristics. As a result of analysis, if the number of order is less than 10 and the quantify of each order is less than 10kg, type III has an advantage over the others And if the number of order is more than 10 and the quantity of each order is more than 10kg, type I has an advantage in the same zone and type II has an advantage in the other zones. This study is limited on the actual application because this study doesn't consider logistics infra of supply company and transport service time. If further study that considers these factors is implemented, it can estimate more accurate logistics cost on EC and propose an efficient freight transport alternatives to the company. This study attributes to estimate the logistics cost change over the frequency of daily order, the quantify of supply goods, and the transport distance on EC.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.168-178
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• 1994

Acid sulfate soils occur extensively in Gimhae area where they have been formed from the brackish alluvial sediments along the sea coast and river estuary. The strong acid environment enhances silicate weathering and thus affects the soil clay minerals. The minerals were identified through chemical, X-ray diffraction and thermal methods. The ratio of $SiO_2$ and $Al_2O_3$ in the clay fractions ranged from 3.14 to 3.77, indicating that the distribution of the clay minerals were 1 : 1 and 2 : 1 minerals. Cation exchange capacity in the clay fractions was low due to high contents of 1 : 1 minerals and hydroxy interlayered vermiculite(HIV). The B and C horizon rich in jarosite have large amounts of yellow streaks which reflect high content of $Fe_2O_3$ and $K_2O$. Vermiculite and illite were quantified from thermogravimetry(TG), kaolin minerals from both TG and differential thermal analysis(DTA), and HIV from X-ray diffraction analysis. The dominant clay minerals were kaolin minerals, vermiculite, illite and HIV. HIV considered to be formed, especially, in acid soil environments. The minor minerals were quarts, feldspar, jarosite, pyrite, hematite and goethite. Kaolin minerals were the most abundant clay minerals throughout the acid sulfate soil. Kaolin minerals, however, increased towards the top of horizons throughout the soils and HIV decreased towards the top of horizons in the soil of Gimhae series and Haecheog series. Alteration of HIV to kaolin minerals during weathering of low pH condition in deep soil horizons may explain the high quantities of kaolin minerals and the relatively low quantities of HIV in the soil at top horizons.

• Journal of the Korean earth science society
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• v.24 no.6
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• pp.568-577
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• 2003

The purpose of this paper is to examine the geomorphic processes of beach and sanddune development in the Chungcheong-Namdo Province. The sands consist mainly of quartz and feldspar with lesser amounts of mica and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is low degrees of roundness and grading indicating that source areas for the material were in the vicinity of the accumulating field. Over the years, the beaches have receded as a response to the decreasing amount of depositional materials. The driving force for the formation and transformation of coastal dunes in the study area is dominant winds from the center of the Siberian High. To some extent, the erosion of coastal dunes has been a global phenomenon. The degradation process occurred most actively when spring tides attacked beaches, berms, and foredunes. The relief and shape of present-day coastal dunes is determined initially by the Pleistocene strata underneath. From the fact that the strata contained traces of frozen structure, it can be inferred that sediment once experienced the process of soil formation.

• Resources Recycling
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• v.12 no.5
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• pp.29-35
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• 2003

$\beta$-Sialon is synthesized by carbo-thermal reduction and nitriding (CTRN) method, using the Fly ash from power plant. $\beta$-Siaion is synthesized at $1,450^{\circ}C$ for 10 hours, and sintered at $1,550 ^{\circ}C$ for 3 hours in nitrogen atmosphere. The XRD analytical results show that the sintered $\beta$-Sialon contains $SiO_2$ and $FeSi_{x}$ of inter-metallic compound. The sintered $\beta$-Sialon is stable against the oxidation at the temperature of 1,31$0^{\circ}C$ for 20 hours. The weight of the sample increases rapidly by oxidation reaction at $1,360^{\circ}C$. The oxide scale is consisted with mullite phase when it is oxidized at the temperature of $1,360 ^{\circ}C$ for 10 hours.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.23-33
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• 2002

Examined a practical use possibility of paper fly ash that is industrial by-product as a stabilization/hardening agent. Performed unconfined compression test, scanning electron microscopy and pH analysis etc. for 100% paper fly ash-soil mixtures and each paper fly ash-soil mixtures that add cement as the second addition and sulfate component of small quantity for strength promotion and so on. In all cases, strength of admixtures increased according as curing time and mixing ratio increases but almost strength is revealed at mixing early and expressed maximum strength increase efficiency at mixing ratio 9% with raw soil. Compare with the case that use paper fly ash only, in case of cement amount 10~30% was included in paper fly ash, strength of admixtures increases two times and 40% was included, that increases from five to eight times.

• Journal of the Korean Magnetics Society
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• v.19 no.6
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• pp.227-232
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• 2009

Fe compounds of scoria samples distributed in the western seaside area of Jeju island were investigated by means of X-ray fluorescence spectroscopy (XRD), X-ray diffractometry (XRF) and $^{57}Fe$ Mossbauer spectroscopy. The samples were prepared from five parasite volcanos. We found that the samples were a typical basalt from the contents ratio of $SiO_2,\;Al_2O_3$ and Fe, and that they were silicate minerals. Underwater volcanoes scoria samples are shown only doublets in Mossbauer spectra and others scoria samples are shown sextets due to hematite and magnetite. And the balence state of Fe in the underwater volcanoes scoria samples are chiefly 2+ charge state with a little of the 2+ charge state. But the balence state of Fe in the others scoria samples are chiefly 3+ charge state.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.64-70
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• 1984

In this experiment, the changes in the components of carbohydrate and their enzyme activities were investigated to study the conversion of sugars in tomato under sub-atmospheric pressure storage .The results obtained are as follows: The soluble sugars in tomato fruits were, for the most part, fructose and glucose together with small quantity of sucrose and maltose. The content of fructose increased throughout the storage, while that of glucose increased at an early stage but decreased at the latter part, and that of sucrose decreased drastically with progress of storage. The activity of ${\alpha}-amylase$ and invertase playing important roles in conversion of sugars showed a rapid increase at onset of respiration climacteric, resulting that the content of total soluble sugar showed a tendency to decrease strikingly, whereas those of starch and sucrose to decrease rapidly. Thus, the effect of temperature was more pronounced than that of pressure.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.15-30
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• 2002

최근 화장품 사용인구의 증가와 안전성에 대한 관심 증대에 따라 화장품 중 유해성분 함유에 대한 논란이 종종 있어왔다. 화장품에 대한 전문적 지식이 없는 사람들에 의하여 진행된 잘못된 정보로 인하여 화장품 중에 포함된 모든 중금속이 인체에 심각한 영향을 초래한다는 등의 오해를 불러와 관련 업계에 적지 않은 피해를 주기도 하였다. 이에 본 자료에서는 구체적 근거자료와 연구 논문들을 기반으로 유해한 중금속, 안전하여 사용이 공인된 중금속 등을 조사하여 화장품에서의 중금속의 개념을 정립하고자 하였다. 국내에서는 식품의약품안전청 고시 제2000-27호에 화장품에 포함되었을 때 유해한 중금속으로 납, 비소 및 수은을 명시하고 그 규제농도를 규정하고 있다. 규제 중금속은 아니지만 피부에 알러지를 일으키는 중금속으로는 니켈이 있는데 화장품 중 몇몇 제품군에서 소량(수∼수십ppm) 이 검출되기도 한다. 그러나 이는 일상으로 사용하는 각종 귀금속, 시계, 안경테, 클립, 지퍼 등의 금속 용품에 포함된 니켈의 양(수∼수십%)에 비하여 매우 적은 양이며 정상적인 사람에게는 무해하다. 실제 대다수의 니켈 알러지는 화장품이 아닌 귀금속이나 시계 등의 금속류 제품 등에 의하여 유발된다. 또한 많은 종류의 중금속 화합물이 화장품 원료로 사용되고 있다. 전세계적으로 널리 사용되는 것으로 크롬, 망간, 비스머스, 구리, 철, 코발트, 티타늄, 아연 등의 화합물이 있으며 이들은 각종 화장품 공정서 및 원료집 등에 수재되어 사용되고 있다. 이들 중 코발트와 크롬이 피부에 유해하다는 몇몇 보고가 있지만, 이는 이들 원소의 수용성염형태의 특정 화합물인 cobalt chloride와 chromate 및 dichromate의 염에 관한 것으로 화장품에서 사용되는 불용성 산화물인 cobalt aluminum oxide, cobalt titanium oxide, cobalt blue, chromium oxde greens 및 chromium hydroide green 등, 국제적으로 널리 사용되는 안전한 중금속 화합물과는 그 특성 및 독성이 판이하게 다르다. 따라서 화장품에서는 매우 안전한 중금속 화합물만이 사용된다. 업계는 유해 중금속에 관해서는 규제에 입각한 엄격한 품질관리에 힘쓰고 중금속의 화학적 분자구조(수용성염 vs 불용성산화물)를 구별할 수 있는 분석방법 개발에 주력하여야 한다. 그리고 안전한 화장품을 사용하고자 하는 소비자의 욕구를 충족시키고 잘못된 인식과 보도로 인하여 안전한 화장품이 유해한 것으로 오도되는 것을 막아야 할 것이다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.225-231
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• 2006

On-line shopping allows consumers to order goods via internet and receive them at homes or workplaces. Emergence of online shopping industry has brought the changes in the structure of freight industry, in the location selection pattern of industrial clusters and in the consumer's travel pattern. This trend is likely to continue, especially in Korea, as the society sees increases in women's participation in workforce, in population of the elder and in production pattern of manufacturing individually customized goods. Despite on-line shopping's heavy influence on travel demand, no study on this particular topic has been done yet, and thus the effect of on-line shopping on travel demand has not been properly reflected on policy making process. This paper suggests the transportation strategy to cope with this change based on the analysis of the effect of on-line shopping on personal travel demand.

• Resources Recycling
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• v.2 no.2
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• pp.27-38
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• 1993

In this study, we investigated the grinding and sedimentation(elutriation) process of the dusts for the effective separation of high purity iron and iron oxides. For characterization of the dust, particle size distribution and chemical composition, were examined. The results obtained in this study may be summarized as follows : 1. The converter CF(clarifier) dust of the Pohang 1st, 2nd steel making factory and EC(Evaporation Cooler), EP(Eltrostatic precititator) dust of the Kwangyang 2nd steel making factory are composed $\alpha$-Fe(21~50%), FeO(wustite)$Fe_3$$O_4$(magnetite), $Fe_2$$O_3$, CaO, $Al_2$$O_3$, $SiO_2$, and etc. 2. Pure iron has ductile characteristic in nature, particle size of the pure iron increase by increasing the grinding time. On the other hand, it is conformed that bo고 particles of hematite and magnetite become less than 325 mesh after 10 minutes grinding. 3. By applying the elutriation technique for the EC dust of the Kwangyang 2nd steel making factory, the iron powder of high content more than 99.17% of pure Fe was recovered with 37.8% yield at grinding time for 40 minutes. 4. By applying the elutriation technique for the CF dust of the Pohang 2nd steel making factory, the iron powder of high content more than 98.38% of pure Fe was recovered with 44.42% yield at grinding time for 40 minutes. 5. When magnetic separation was performed using plastic bonding magnet of 70 gauss, more than 98% Fe grade of iron powder was recovered in the size range +65 -200 mesh but the recovery of it was low.