• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.67-74
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• 2015

In recent years, frequent itemset mining for considering the importance of each item has been intensively studied as one of important issues in the data mining field. According to strategies utilizing the item importance, itemset mining approaches for discovering itemsets based on the item importance are classified as follows: weighted frequent itemset mining, frequent itemset mining using transactional weights, and utility itemset mining. In this paper, we perform empirical analysis with respect to frequent itemset mining algorithms based on transactional weights. The mining algorithms compute transactional weights by utilizing the weight for each item in large databases. In addition, these algorithms discover weighted frequent itemsets on the basis of the item frequency and weight of each transaction. Consequently, we can see the importance of a certain transaction through the database analysis because the weight for the transaction has higher value if it contains many items with high values. We not only analyze the advantages and disadvantages but also compare the performance of the most famous algorithms in the frequent itemset mining field based on the transactional weights. As a representative of the frequent itemset mining using transactional weights, WIS introduces the concept and strategies of transactional weights. In addition, there are various other state-of-the-art algorithms, WIT-FWIs, WIT-FWIs-MODIFY, and WIT-FWIs-DIFF, for extracting itemsets with the weight information. To efficiently conduct processes for mining weighted frequent itemsets, three algorithms use the special Lattice-like data structure, called WIT-tree. The algorithms do not need to an additional database scanning operation after the construction of WIT-tree is finished since each node of WIT-tree has item information such as item and transaction IDs. In particular, the traditional algorithms conduct a number of database scanning operations to mine weighted itemsets, whereas the algorithms based on WIT-tree solve the overhead problem that can occur in the mining processes by reading databases only one time. Additionally, the algorithms use the technique for generating each new itemset of length N+1 on the basis of two different itemsets of length N. To discover new weighted itemsets, WIT-FWIs performs the itemset combination processes by using the information of transactions that contain all the itemsets. WIT-FWIs-MODIFY has a unique feature decreasing operations for calculating the frequency of the new itemset. WIT-FWIs-DIFF utilizes a technique using the difference of two itemsets. To compare and analyze the performance of the algorithms in various environments, we use real datasets of two types (i.e., dense and sparse) in terms of the runtime and maximum memory usage. Moreover, a scalability test is conducted to evaluate the stability for each algorithm when the size of a database is changed. As a result, WIT-FWIs and WIT-FWIs-MODIFY show the best performance in the dense dataset, and in sparse dataset, WIT-FWI-DIFF has mining efficiency better than the other algorithms. Compared to the algorithms using WIT-tree, WIS based on the Apriori technique has the worst efficiency because it requires a large number of computations more than the others on average.

• Journal of Global Scholars of Marketing Science
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• v.8
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• pp.233-267
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• 2001

The management environment in Korea today is undergoing rapid changes; in particular, domestic corporations and businesses are confronting formidable adversity with IMF crisis and WTO. Though cost cutback, higher quality, rapid production, and diversification of products were accepted as important requirements for competitiveness in the past, they have been replaced by brand power. Consumption patterns have changed their focus from function to image orientation. This is why managers in corporations have invested enormous amounts of resources into producing powerful brands, which can attract consumers' attention greatly enough to improve the image of their products. Brands are regarded as a vital vehicle for marketing strategies and thus as a legal asset. Brands with remarkable and favorable image can secure a loyal consumer groups stable revenues. M & A, currently active between corporations, makes brand equity all the more important. The purpose of the present study was to investigate the effect of internal marketing and increased brand diversification on brand equity by combining them as influential factors with marketing mix factor. For this purpose, literature review was make on previous fragmented studies of influential factors on brand equity build-up. Based on the findings of this study, some operational implications were suggested for marketing managers. The findings and implications of the present study are as follows; First, efficient communication among organization members was found to have a significant effect on product quality. Second, job satisfaction and efficient communication among members was shown to significantly influence price policies. Thirdly, efficient communication among organization workers proved to have a significant effect on distribution strategies. Forth, efficient communication among members was demonstrated to significantly influence advertisement and other public-relations activities. Fifth, opacity of market environment appeared to have a significant effect on product quality, prior market entrance as perceived by organization members turned to be of negative influence on product quality. Sixth, opacity of market environment was found to have a significant effect on price policies. Seventh, opacity of market environment was shown to be of significant effect on distribution strategies. Eighth, grater opacity of market environment proved to improve advertisement and other public-relations activities. Ninth, price policies, distribution strategies, advertisement and public-relations activities were found to have a significant effect on brand equity value. To sum up these findings, in order for corporations and businesses to cope with consumers' needs that are increasingly segmented, internal marketing strategies and brand diversification should be implemented so as to generate greater synergy effect. It is also important to stress that differentiated, higher competitiveness should be secured for Korean corporations and businesses to survive in the drastically changing, globalized market environment. In this regard, continuous and long-term management strategies for brand equity build-up should be ensured and is essential in the present unlimited competition. The last but not least important point to notice is that to increase brand equity value, intensive investment and constant emphasis should be made on internal marketing management on intra-organizational members before strengthening external marketing.

• Journal of Korean Society of Transportation
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• v.22 no.1 s.72
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• pp.43-62
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• 2004

Conventionally the estimation method of the origin-destination Matrix has been developed by implementing the expansion of sampled data obtained from roadside interview and household travel survey. In the survey process, the bigger the sample size is, the higher the level of limitation, due to taking time for an error test for a cost and a time. Estimating the O-D matrix from observed traffic count data has been applied as methods of over-coming this limitation, and a gradient model is known as one of the most popular techniques. However, in case of the gradient model, although it may be capable of minimizing the error between the observed and estimated traffic volumes, a prior O-D matrix structure cannot maintained exactly. That is to say, unwanted changes may be occurred. For this reason, this study adopts a conjugate gradient algorithm to take into account two factors: estimation of the O-D matrix from the conjugate gradient algorithm while reflecting the prior O-D matrix structure maintained. This development of the O-D matrix estimation model is to minimize the error between observed and estimated traffic volumes. This study validates the model using the simple network, and then applies it to a large scale network. There are several findings through the tests. First, as the consequence of consistency, it is apparent that the upper level of this model plays a key role by the internal relationship with lower level. Secondly, as the respect of estimation precision, the estimation error is lied within the tolerance interval. Furthermore, the structure of the estimated O-D matrix has not changed too much, and even still has conserved some attributes.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.33-40
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• 2013

From March 2012 to January 2013, this study was conducted as a part of the project for making a precise electronic ecological zoning map of vegetation on a highly reduced scale of 1 to 5,000 with a view to improving management efficiency of national parks and enlarging the availability of the data produced from the basic research monitoring the resources of national parks. For the research accuracy and rapidity, a vegetation map was specially created for the on-the-site-vegetation research. To make the map more meticulous, we categorized the vegetation database into five groups: broadleaved forest, coniferous forest, mixed forest, rock vegetation and miscellaneous one. After comparing the results of the data built for the vegetation research and the actual research findings, it was made clear that vegetation of both categories was almost the same in case of broad-leaved forest with 72.20% and 78.45% respectively, and also equivalent in other groups like, for example, coniferous forest (16.70%, 13.41%), mixed forest (9.50%, 7.49%) and rock vegetation (0.60%, 0.15%). According to the precise vegetation map produced from the research, the deciduous broad-leaved forest was the most widely prevalent type in the correlated hierarchical classification of vegetation, occupying 65.78% of the overall vegetation. It was followed by mountain valley forest (15.17%), coniferous forest (10.90%), and plantation forest (7.00%) in order. It is particularly noteworthy that Mt. Deogyusan national park has retained a very stable and versatile forest vegetation in the outstanding state since approximately 20% of the mountain turns out to belong to the I grade vegetation conservation classification which contains climax forests, unique vegetation, subalpine vegetation, matured stands which are older than 50 years and etc.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.93-100
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• 2011

Maintenance of adequate soil water potential during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement within and below the rooting zone can facilitate optimal irrigation scheduling aimed at minimizing the adverse effects of water stress on crop growth and development and the leaching of water below the root zone which can have adverse environmental effects. The objective of this study was to evaluate the feasibility of using a portable irrigation controller with an Watermark sensor for the cultivation of drip-irrigated vegetable crops in a greenhouse. The control capability of the irrigation controller for a soil water potential of -20 kPa was evaluated under summer conditions by cultivating 45-day-old tomato plants grown in three differently textured soils (sandy loam, loam, and loamy sands). Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30 cm depths. Even though a repeatable cycling of soil water potential occurred for the potential treatment, the lower limit of the Watermark (about 0 kPa) obtained in this study presented a limitation of using the Watermark sensor for optimal irrigation of tomato plants where -20 kPa was used as a point for triggering irrigations. This problem might be related to the slow response time and inadequate soil-sensor interface of the Watermark sensor as compared to a porous and ceramic cup-based tensiometer with a sensitive pressure transducer. In addition, the irrigation time of 50 to 60 min at each of the irrigation operation gave a rapid drop of the potential to zero, resulting in over irrigation of tomatoes. There were differences in water content among the three different soil types under the variable rate irrigation, showing a range of water contents of 16 to 24%, 17 to 28%, and 24 to 32% for loamy sand, sandy loam, and loam soils, respectively. The greatest rate increase in water content was observed in the top of 10 cm depth of sandy loam soil within almost 60 min from the start of irrigation.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.1
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• pp.25-34
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• 2020

Land use in watersheds has been shown to be a major driving factor in determining the status of the water quality of streams. In this light, scientists have been investigating the roles of riparian vegetation on the relationships between land use in watersheds and the associated stream water quality. Numerous studies reported that riparian vegetation could alleviate the adverse effects caused by land use in watersheds and on stream water quality through various hydrological, biochemical and ecological mechanisms. However, this concept has been criticized as the true effects of riparian vegetation must be assessed by comprehensive models that mimic real environmental settings. This study aimed to estimate a comprehensive structural equation model integrating topography, land use, and characteristics of riparian vegetation. We used water quality data from the Nakdong River system monitored under the National Aquatic Ecosystem Monitoring Program (NAEMP) of the Korean Ministry of Environment (MOE). Also, riparian vegetation data and land use data were extracted from the Land Use/Land Cover map (LULC) produced by the MOE. The number of structural equation models (SEMs) were estimated in Amos of IBM SPSS. Study results revealed that land use was determined by elevation, and developed areas within a watershed significantly increased the concentration of Total Nitrogen (TN) in streams and LDI in riparian vegetation. On the contrary, developed areas significantly reduced LPI and PLAND. At the same time, PLAND and LDI significantly reduced the concentration of TN in streams. Thus, it was clear that developed areas in watersheds had both a direct and an indirect impact on the concentration of TN in streams, and spatial pattern and the amount of vegetation of riparian vegetation could significantly alleviate the negative impacts of developed areas on TN concentration in streams. To enhance stream water quality, reducing developed areas in a watershed is critical for long-term watershed management plans, restoration patterns for riparian vegetation could be immediately implemented since riparian areas were less developed than most other watersheds.

• Food preservation and processing industry
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• v.8 no.2
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• pp.6-12
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• 2009

면역반응은 외부 감염원으로부터 신체를 보호하고 외부감염원을 제거하고자 하는 주요항상성 유지기전의 하나이다. 이들 반응은 골수에서 생성되고 비장, 흉선 및 임파절 등에서 성숙되는 면역세포들에 의해 매개된다. 보통 태어나면서부터 얻어진 선천성 면역반응을 매개하는 대식세포, 수지상 세포 등과, 오랜기간 동안 감염된 다양한 면역원에 대한 경험을 토대로 얻어진 획득성 면역을 담당하는 T 임파구 등이 대표적인 면역세포로 알려져 있다. 다양한 면역질환이 최근 주요 사망률의 원인이 되고 있다. 최근, 암, 당뇨 및 뇌혈관질환 등이 생체에서 발생되는 급 만성염증에 의해 발생된다고 보고됨에 따라 면역세포 매개성 염증질환에 대한 치료제 개발을 서두르고 있다. 또한 암환자의 급격한 증가는 암발생의 주요 방어기전인 면역력 증강에 대한 요구들을 가중시키고 있다. 예로부터 사용되어 오던 고려인삼과 홍삼은 기를 보호하고 원기를 회복하는 명약으로 알려진 대표적인 우리나라 천연생약이다. 특별히, 홍삼은 단백질과 핵산의 합성을 촉진시키고, 조혈작용, 간기능 회복, 혈당강하, 운동수행 능력증대, 기억력 개선, 항피로작용 및 면역력 증대에 매우 효과가 좋은 것으로 보고되고 있다. 홍삼에 관한 많은 연구에 비해, 현재까지 홍삼이 면역력 증강에 미치는 효과에 대한 분자적 수준에서의 연구는 매우 미미한 것으로 확인되어져 있다. 홍삼의 투여는 NK 세포나 대식세포의 활성이 증가하고 항암제의 암세포 사멸을 증가시키는 것으로 확인되어졌다. 현재까지 알려진 주요 면역증강 성분은 산성다당류로 보고되었다. 또 한편으로 일부 진세노사이드류에서 항염증 효능이 확인되어졌으며, 이를 통해 피부염증 반응과 관절염에 대한 치료 효과가 있는 것으로 추측되고 있다 [본 연구는 KT&G 연구출연금 (2009-2010) 지원을 받아 이루어졌기에 이에 감사드린다]. 면역반응은 외부 감염물질의 침입으로 유도된 질병환경을 제거하고 수복하는 중요한 생체적 방어작용의 하나이다. 이들 과정은 체내로 유입된 미생물이나 미세화학물질들과 같은 독성물질을 소거하거나 파괴하는 것을 주요 역할로 한다. 외부로 부터 인체에 들어온 이물질에 대한 방어기전은 현재 두 가지 종류의 면역반응으로 구분해서 설명한다. 즉, 선천성 면역 반응 (innate immunity)과 후천성 면역 반응 (adaptive immunity)이 그것이다. 선천성 면역반응은 1) 피부나 점막의 표면과 같은 해부학적인 보호벽 구조와 2) 체온과 낮은 pH 및 chemical mediator (리소자임, collectin류) 등과 같은 생리적 방어구조, 3) phagocyte류 (대식세포, 수지상세포 및 호중구 등)에 의한 phagocytic/endocytic 방어, 그리고 4) 마지막으로 염증반응을 통한 감염에 저항하는 면역반응 등으로 구분된다. 후천성 면역반응은 획득성면역이라고도 불리고 특이성, 다양성, 기억 및 자기/비자기의 인식이라는 네 가지의 특징을 가지고 있으며, 외부 유입물질을 제거하는 반응에 따라 체액성 면역 반응 (humoral immune response)과 세포성 면역반응 (cell-mediated immune response)으로 구분된다. 체액성 면역은 침입한 항원의 구조 특이적으로 생성된 B cell 유래 항체와의 반응과 간이나 대식세포 등에서 합성되어 분비된 혈청내 보체 등에 의해 매개되는 반응으로 구성되어 있다. 세포성 면역반응은 T helper cell (CD4+), cytotoxic T cell (CD8+), B cell 및antigen presenting cell 중개를 통한 세포간 상호 작용에 의해 발생되는 면역반응이다. 선천성 면역반응의 하나인 염증은 우리 몸에서 가장 빈번히 발생되고 있는 방어작용의 하나이다. 예를 들면 감기에 걸렸을 경우, 환자의 편도선내 대식세포나 수지상세포류는 감염된 바이러스 단독 혹은 동시에 감염된 박테리아를 상대로 다양한 염증성 반응을 유도하게 된다. 또한, 상처가 생겼을 경우에도 감염원을 통해 유입된 병원성 세균과 주위조직내 선천성 면역담당 세포들 간의 면역학적 전투가 발생되게 된다. 이들 과정을 통해, 주위 세포나 조직이 손상되면, 즉각적으로 이들 면역세포들 (주로 phagocytes류)은 신속하게 손상을 극소화하고 더 나가서 손상된 부위를 원상으로 회복시키려는 일련의 염증반응을 유도하게 된다. 이들 반응은 우리가 흔히 알고 있는 발적 (redness), 부종 (swelling), 발열 (heat), 통증 (pain) 등의 증상으로 나타나게 된다. 즉, 손상된 부위 주변에 존재하는 모세혈관에 흐르는 혈류의 양이 증가하면서 혈관의 직경이 늘어나게 되고, 이로 인한 조직의 홍반과, 부어 오른 혈관에 의해 발열과 부종이 초래되는 것이다. 확장된 모세혈관의 투과성 증가는 체액과 세포들이 혈관에서 조직으로 이동하게 하는 원동력이 되고, 이를 통해 축적된 삼출물들은 단백질의 농도를 높여, 최종적으로 혈관에 존재하는 체액들이 조직으로 더 많이 이동되도록 유도하여 부종을 형성시킨다. 마지막으로 혈관 내 존재하는 면역세포들은 혈판 내벽에 점착되고 (margination), 혈관벽의 간극을 넓히는 역할을 하는 히스타민 (histamine)이나 일산화질소(nitric oxide : NO), 프로스타그린딘 (prostagladins : PGE2) 및 류코트리엔 (leukotriens) 등과 같은 chemical mediator의 도움으로 인해 혈관벽 사이로 삼출하게 되어 (extravasation), 손상된 부위로 이동하여 직접적인 외부 침입 물질의 파괴나 다른 면역세포들을 모으기 위한 cytokine (tumor necrosis factor [TNF]-$\alpha$, interleukin [IL]-1, IL-6 등) 혹은 chemokine (MIP-l, IL-8, MCP-l등)의 분비 등을 수행함으로써 염증반응을 매개하게 된다. 염증과정시 발생되는 여러 mediator 중 PGE2나 NO 및 TNF-$\alpha$ 등은 실험적 평가가 용이하여 이들 mediator 자체나 생성관련효소 (cyclooxygenase [COX] 및 nitric oxide synthase [NOS] 등)들은 현재항염증 치료제의 개발 연구시 주요 표적으로 연구되고 있다. 염증 반응은 지속기간에 따라 크게 급성염증과 만성염증으로 나뉘며, 삼출물의 종류에 따라서는 장액성, 섬유소성, 화농성 및 출혈성 염증 등으로 구분된다. 급성 염증 (acute inflammation)반응은 수일 내지 수주간 지속되는 일반적인 염증반응이라고 볼 수 있다. 국소반응은 기본징후인 발열과 발적, 부종, 통증 및 기능 상실이 특징적이며, 현미경적 소견으로는 혈관성 변화와 삼출물 형성이 주 작용이므로 일명 삼출성 염증이라고 한다. 만성 염증 (chronic inflammation)은, 급성 염증으로부터 이행되거나 만성으로 시작된다. 염증지속 기간은 보통 4주 이상 장기화 된다. 보통 염증의 경우에는 염증 생성 cytokine인 Th1 cytokine (IL-2, interferone [IFN]-$\gamma$ 및 TNF-$\alpha$ 등)의 생성 후, 거의 즉각적으로 항 염증성 cytokine인 Th2 cytokine(IL-4, IL-6, IL-10 및 transforming growth factor [TGF]-$\beta$ 등)이 생성되어 정상반응으로 회복된다. 그러나, 어떤 원인에서든 면역세포에 의한 염증원 제거 반응이 문제가 되면, 만성염증으로 진행된다. 이 반응에 주로 작용을 하는 염증세포로는 단핵구와 대식세포, 림프구, 형질세포 등이 있다. 암은 전세계적으로 사망률 1위의 원인이 되는 면역질환의 하나이다. 산화적 스트레스나 자외선 조사 혹은 암유발 물질들에 의해 염색체내 protooncogene, tumor-suppressor gene 혹은 DNA repairing gene의 일부 DNA의 돌연변이 혹은 결손 등이 발행되면 정상세포는 암화과정을 시작하게 된다. 양성세포 수준에서 약 5에서 10여년 후 악성수준의 암세포가 생성되게 되면 이들 세포는 새로운 환경을 찾아 전이하게 되는데 이를 통해 암환자들은 다양한 장기에 동인 오리진의 암세포들이 생성한 종양들을 가지게 된다. 이들 종양세포는 정상 장기의 기능을 손상시켜며 결국 생명을 잃게 만든다. 이들 염색체 수준에서의 돌연변이 유래 암세포는 거의 대부분이 체내 면역시스템에 의해 사멸되는 것으로 알려져 있다. 그러나 계속되는 스트레스나 암유발 물질의 노출은 체내 면역체계를 파괴하면서 최후의 방어선을 무너뜨리면서 암발생에 무방비 상태를 만들게 된다. 이런 이유로 체내 면역시스템의 정상적 가동 및 증강을 유도하게 하는 전략이 암예방시 매우 중요한 표적으로 인식되면서 다양한 형태의 면역증강 물질 개발을 시도하고 있다. 인삼은 두릅나무과의 여러해살이 풀로써, 오랜동안 한방 및 민간에서 원기를 회복시키고, 각종 질병을 치료할 수단으로 사용되고 있는 대표적인 전통생약이다. 예로부터 불로(不老), 장생(長生), 익기(益氣), 경신(經身)의 명약으로 구전되어졌는데, 이는 약 2천년 전 중국의 신농본초경(神農本草經)에서 "인삼은 오장(五腸)을 보하고, 정신을 안정시키고, 혼백을 고정하며 경계를 멈추게 하고, 외부로부터 침입하는 병사를 제거하여주며, 눈을 밝게 하고 마음을 열어 더욱 지혜롭게 하고 오랫동안 복용하면 몸이 가벼워지고 장수한다" 라고 기술되어있는 데에서 유래한 것이다. 다양한 연구를 통해 우리나라에서 생산되는 고려인삼 (Panax ginseng)이 효능 면에서 가장 탁월한 것으로 알려져 있으며 특별이 고려인삼으로부터 제조된 고려홍삼은 전세계적으로도 그 효능이 우수한 것으로 보고되어 있다. 대부분의 홍삼 약효는 dammarane계열의 triterpenoid인 ginsenosides라고 불리는 인삼 saponin에 의해 기인된 것으로 알려져 있다. 이들 화합물군의 기본 골격에 따라, protopanaxadiol (PD)계 (22종) 및 protopanaxatriol (PT)계 (10종)으로 구분되고 있다 (표 1). 실험적 접근을 통해 인삼의 약리작용 이해를 위한 다양한 노력들이 경주되고 있으나, 여전히 많은 부분에서 충분히 이해되고 있지 않다. 그러나, 현재까지 연구된 인삼의 약리작용 관련 연구들은 심혈관, 당뇨, 항암 및 항스트레스 등과 같은 분야에서 인삼효능이 우수한 것으로 보고하고 있다. 그러나 면역조절 및 염증현상과 관련된 최근 연구결과들은 많지 않으나, 향후 다양하게 연구될 효능부분으로 인식되고 있다.

• Restorative Dentistry and Endodontics
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• v.35 no.5
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• pp.387-394
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• 2010

Objectives: The purpose of this study was to evaluate the whitening efficacy and longevity of home bleaching. Materials and Methods: A total of 28 patients were divided into either experimental group (Opalescence F; 15% carbamide peroxide) or control group randomly. The patients in experimental group were instructed to wear individual trays applied with bleaching gel for 2 hours a day for 4 weeks. Any treatments weren't applied to the patients in control group. The color measurements of central incisors, lateral incisors & canines of upper and lower arch were recorded at base line, immediately after the finishment of treatmemt (4 weeks), 8 weeks and 12 weeks using Colorimeter (Chroma Meter, 2600d Konica Minolta co.) and Vitapan classical shade guide (Vita Zahnfabrik). Results: A significantly stronger color change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group (p < 0.05). There was also a significant difference between baseline and 8 weeks or 12 weeks separately though color rebouncing phenomenon occurred as time went by (p < 0.05). Conclusions: The clinical effecacy and longevity of home bleaching without combined application of in-office bleaching was observed through this experiment.

• Analytical Science and Technology
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• v.8 no.1
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• pp.91-99
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• 1995

One of alternative conventional technologies used for treatment of livestock wastes is composting process, and recently some mechanical composting processes are being practiced. It is, however, recognized the composting process also has its own limitations such as longer time requirement, and difficulties to estimate the degree of decomposition, etc. The incomplete compost contains potentially harmful materials to crops and public health due to instabilized organic contents and pathogenic organisms. The purpose of this investigation is to develop an innovative system whereby anxious livestock wastes are thoroughly stabilized and disinfected. Thus the overall management scheme should meet the following requirements. 1. A system should be in a cost-effective and environmentally sound manner. 2. Sludges must be chemically stabilized and bacteriologically safe. 3. Odor-free by product should be applied to crop land. 4. Sludges are sources of fertilizer nutrients and/or soil amendments to enhance crop production. 5. And they can be used as potential pH adjusting agent of the acidified soils. Overall effectiveness of the developed system is experimentally tested to satisfy the preset criteria and requirements. Major experiments are divided into four categories: they are 1. chemical stability test, 2. optimal condition test of stabilization process, 3. bacteriological examination and disinfection tests, and 4. deodorization tests The stabilization process is consisted of the stabilizing reaction process and the drying process. Stabilized wastes is dried by both sun dryer and rotary dryer. It is shown that an additive dosage of about g/kg solid in wastes with a minimum of 5-minutes reaction would be necessary for effective stabilization reaction. The stabilization process is consisted of the stabilizing reaction process and drying process. Stabilized wastes are dried by both sun dryer and rotary dryer. It is shown that an additive dosage of about 300g/kg solid in wastes with a minimum of 5-minutes reaction would be necessary for effective stabilization reaction. In the stabilization reaction process, the pH of wastes is lowered from initial values of 12.3 to 8.6. High pH prevents odor production and kills pathogenic organisms. Organic matter contents in the stabilized wastes are about 50% and the sum of contents of fertilizer elements such as total nitrogen, $P_2O_5$ and $K_2O$ are about 5.3%. The livestock wastes that are stabilized chemically and hygienically can be used as a good soil conditioner and/or organic fertilizer.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.122-142
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• 2009

This study explored all domestic and international theories for maintenance and health enhancement of an old and big tree, and carried out the anatomical survey of the operation part of the tree toward he current status of domestic surgery and the perception survey of an expert group, and drew out following conclusion through the process of suggesting its reform plan. First, as a result of analyzing the correlation of the 67 subject trees with their ages, growth status. surroundings, it revealed that they were closely related to positional characteristic, damage size, whereas were little related to materials by fillers. Second, the size of the affected part was the most frequent at the bough sheared part under $0.09m^2$, and the hollow size by position(part) was the biggest at 'root + stem' starting from the behind of the main root and stem As a result of analyzing the correlation, the same result was elicited at the group with low correlation. Third, the problem was serious in charging the fillers (especially urethane) in the big hollow or exposed root produced at the behind of the root and stem part, or surface-processing it. The benefit by charging the hollow part was analyzed as not so much. Fourth, the surface-processing of fillers currently used (artificial bark) is mainly 'epoxy+woven fabric+cork', but it is not flexible, so it has brought forth problems of frequent cracks and cracked surface at the joint part with the treetextured part. Fifth, the correlation with the external status of the operated part was very high with the closeness, surface condition, formation of adhesive tissue and internal survey result. Sixth, the most influential thing on flushing by the wrong management of an old and big tree was banking, and a wrong pruning was the source of the ground part damage. In pruning a small bough can easily recover itself from its damage as its formation of adhesive tissue when it is cut by a standard method. Seventh, the parameters affecting the times of related business handling of an old and big tree are 'the need of the conscious reform of the manager and related business'. Eighth, a reform plan in an institutional aspect can include the arrangement of the law and organization of the old and big tree management and preservation at an institutional aspect. This study for preparing a reform plan through the status survey of the designated old and big tree, has a limit inducing a reform plan based on the status survey through individual research, and a weak point suggesting grounds by any statistical data. This can be complemented by subsequent studies.