• Title/Summary/Keyword: Successful Operation

Search Result 1,193, Processing Time 0.024 seconds

Removal of Nitrate-Nitrogen in Pickling Acid Wastewater from Stainless Steel Industry Using Electrodialysis and Ion Exchange Resin (전기투석과 이온교환수지를 이용한 스테인레스 산업의 산세폐수 내 질산성 질소의 제거)

  • Yun, Young-Ki;Park, Yeon-Jin;Oh, Sang-Hwa;Shin, Won-Sik;Choi, Sang-June;Ryu, Seung-Ki
    • Journal of Environmental Science International
    • /
    • v.18 no.6
    • /
    • pp.645-654
    • /
    • 2009
  • Lab-scale Electrodialysis(ED) system with different membranes combined with before or after pyroma process were carried out to remove nitrate from two pickling acid wastewater containing high concentrations of $NO_3\;^-$(${\approx}$150,000 mg/L) and F($({\approx}$ 160,000 mg/L) and some heavy metals(Fe, Ti, and Cr). The ED system before Pyroma process(Sample A) was not successful in $NO_3\;^-$ removal due to cation membrane fouling by the heavy metals, whereas, in the ED system after Pyroma process(Sample B), about 98% of nitrate was removed because of relatively low $NO_3\;^-$ concentration (about 30,000 mg/L) and no heavy metals. Mono-selective membranes(CIMS/ACS) in ED system have no selectivity for nitrate compared to divalent-selective membranes(CMX/AMX). The operation time for nitrate removal time decreased with increasing the applied voltage from 10V to 15V with no difference in the nitrate removal rate between both voltages. Nitrate adsorption of a strong-base anion exchange resin of $Cl\;^-$ type was also conducted. The Freundlich model($R^2$ > 0.996) was fitted better than Langmuir mode($R^2$ > 0.984) to the adsorption data. The maximum adsorption capacity ($Q^0$) was 492 mg/g for Sample A and 111 mg/g for Sample B due to the difference in initial nitrate concentrations between the two wastewater samples. In the regeneration of ion exchange resins, the nitrate removal rate in the pickling acid wastewater decreased as the adsorption step was repeated because certain amount of adsorbed $NO_3\;^-$ remained in the resins in spite of several desorption steps for regeneration. In conclusion, the optimum system configuration to treat pickling acid wastewater from stainless-steel industry is the multi-processes of the Pyroma-Electrodialysis-Ion exchange.

Expression of Dopamine D2 Receptor in Response to Apomorphine Treatment in the Striatum of the Rat with Experimentally Induced Parkinsonism (파킨슨병 모형 흰쥐의 줄무늬체에서 Apomorphine 투여 방법에 따른 도파민 D2 수용체의 발현)

  • Choi, Seung Jin;Sung, Jae Hoon;Son, Byung Chul;Park, Choon Keun;Kwon, Sung Oh;Kim, Moon Chan;Lee, Sang Won
    • Journal of Korean Neurosurgical Society
    • /
    • v.29 no.7
    • /
    • pp.868-876
    • /
    • 2000
  • Objective : Parkinsonian rat models have generally been characterized by unilateral destruction of both the nigrostriatal pathway and the mesolimbic pathway using the neurotoxin 6-hydroxydopamine. The induction of contraversive turning by apomorphine in these models is thought to reflect the stimulation of supersensitive dopamine D2 receptor or receptor-mediated mechanisms in denervated neostriatum. The present study was undertaken to investigate the expression of dopamine D2 receptor in denervated striatum according to modalities of apomorphine(dopamine agonist) treatment after creating a hemiparkinsonian rat model in which there is 6-hydroxydopamine induced destruction of the unilateral dopaminergic nigrostriatal pathway. Methods : After making complete lesion in left side substantia nigra pars compacta(SNpc) by stereotactic injection of 6-hydroxydopamine into medial and lateral areas of SNpc, and confirming successful animal model by apomorphine induced contraversive turning behavior without recovery and complete destruction of ipsilateral SNpc with tyrosine hydroxylase immunostaining in 7th day after operation, 15 rats of parkinsonian model were studied with or without administration of apomorphine at varying doses and durations. According to the modalities of apomorphine treatment for 4 days, these rats were divided into 3 groups, as not-treated group, intermittently treated group and constantly treated group. For investigating the extent of the expression of dopamine D2 receptor in denervated striatum, immunohistochemical staining by dopamine D2 receptor antibody and Western blot were performed. Results : In the D2 receptor antibody immunohistochemical staining, the mean number of positive stained neurons was highest in not-treated group($20.5{\pm}1.14$) of 3 groups. In constantly treated group, the mean number of positive stained neurons was less($3.9{\pm}1.79$) than intermittently treated group(p<0.05). The Western blotting with the D2 receptor antibody revealed that expression of receptors was also highest in not-treated group and less in constantiy treated group than intermittently treated group. Conclusion : Dopamine D2 receptors in denervated striatum of parkinsonian rat models, which were not treated with apomorphine, revealed to be most highly expressed. And, according to doses and durations of apomorphine administration, desensitization of the receptor was more apt to develop with constant treatment than intermittent treatment. In clinical setting, the authors believe that, in long-term treated parkinsonian patients, desensitization of dopamine receptors due to chronic dopaminergic stimulation seems to be partially related to mechanisms of drug tolerance.

  • PDF

A Study on the Quality Improvement of Red Dot Sight for Grenade Launcher by Parallax Reduction (고속유탄기관총용 조준경의 시차 개선을 통한 조준경 품질 향상에 관한 연구)

  • Kim, Ji-Hoon;Jeung, Bo-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.11
    • /
    • pp.130-135
    • /
    • 2019
  • This study performed the quality improvement of a red dot sight for a 40 mm grenade launcher through parallax reduction. The red dot sight cited in this study is currently in mass production for military use as a non-weapon system. While the red dot sight's parallax currently meets requirements, slightly greater error was observed on the outside of effective optical area of the reflection lens compared to other sights. Parallax is easily affected by eye movement, which can result in aiming error. To improve the red dot sight's quality, this study analyzed why parallax is observed in the effective optical area of the reflection lens and how to reduce it. As a result, the red dot sight demonstrated lower parallax error using the new optical system design with an increased reflection lens thickness and modified components configuration related to the reflection lens assembly. Parallax was calculated and simulated by using a particular program to verify that it decreased. This improvement for the 40 mm. grenade launcher red dot sight more than satisfies requirements, offers advanced capabilities for users, and as a result, successful operation carryout.

An Empirical Study on the Improvment of VTS in Korea (우리나라 선박교통제제도의 개선방안에 관한 실증연구 - 포항항을 중심으로 -)

  • 임을빈;문성혁
    • Journal of the Korean Institute of Navigation
    • /
    • v.21 no.2
    • /
    • pp.47-58
    • /
    • 1997
  • The purpose of this study is to find out the impacts of VTS on the marine safety and users' opinion on the VTS which have been being operated in the port of Pohang for the last 3 years and is to suggest a guideline to the successful operation of VTS in the future. This study is based upon the questionnaire survey and the respondents include 236 masters/mates of merchant vessels who have visited the port of Pohang and 6 pilots who have been working in the port. From the questionnaire results, this study notes the following conclusions related to the VTS operations. (1) A few of the respondents (mainly foreigners) do not understand the entering procedure of the port and the fundamental concept of VTS. Accordingly, the more active VTS services have to be provided for the mariners. (2) It was found that themost dangerous factors in tehvicinity of the port were the floating materials, fishing nets, andillegal fishing activities inthe fairway. Therefore, the proper surveillance, stricter enforcement of Acts and the instructive education for the fishermen are required to avoid the risks. (3) A majority of the respondents agreed the VTS has contributed to the safety of vessel traffic, and they pointed out ' the assiatances in reduced visibililty conditions' is the most important task of VTS. The amount of 75.6% of the respondents answered that they have experienced the assistance from VTS more than 1 time since the system was established in the port of Pohang . Also 44.2% of the respondents considered they were able to avoid marine casualties such as collision, ramming or agrounding with the VTS assistances. (4) 49.2% of the respondents preferred the passive information services , while, 38.8% of them preferred the positive control advices in the case of encountering any potential risks. VTS iperators have to consider seriously when they provide the positive control advices of ship's course and speed. (5) A majority of the respondents confirmed that the prot and its approaches is suitable for the VTS coverge . To extend the service areas of the VTS and to improve radar detecting ability, the use of radar transponders are seen as the ideal method. (6) A minority of the respondents pointed out 'the improper orders or recommendatinos caused by the poor decision making' firstly, ' the language problem(sea-speaking in English)' secondly, as the deficiency of personal qualification. It seems, therefore, theat the personal efforts of the operators and systematic training programmes for them are necessary to solve the problems.

  • PDF

A Study on the Landmark for Regional Revitalization (지역 활성화를 위한 랜드마크 개발)

  • Lim, Chae-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.3
    • /
    • pp.560-570
    • /
    • 2016
  • A landmark is a representative image of a given region that impresses distinct regional characteristics upon visitors. As such, there is a need for each local government to develop a symbolic landmark. We investigated examples of landmark development intended to promote regional revitalization in hopes to provide a basic guideline for developing future landmarks, related tourism products, and tourism promotion policy. Aomori prefecture in Japan was selected as a site for a field study. For a long time, Japan has tried to internationalize and revitalize its provincial regions by establishing various tourism policies. In order to foster the tourism industry in rural areas that are behind in development, Aomori prefecture sought to promote local revitalization through the development of tourism products and cultural space centered on a landmark. Based on this example, we can summarize the conditions for successful landmark development as follows. First, in deciding on the symbolism or the design of a landmark, we must fully investigate and understand the given region and invest sufficient time and funds. Second, we must consider the accessibility of the landmark and make sure its surroundings can also serve as a tourist attraction element. Third, in order to increase the value of visiting a landmark, it is important to provide a variety of things to see and enjoy both inside and outside of the landmark, which can be achieved through continuous operation and management of amenities and diverse programs.

A Study on the Safety-Maximizing Design of Exclusive Bus Lanes (안전성 제고를 위한 버스전용차로 디자인 연구)

  • Yang, Chul-Su
    • Journal of Korean Society of Transportation
    • /
    • v.30 no.4
    • /
    • pp.21-32
    • /
    • 2012
  • Exclusive bus lane (EBL) is typically located in the roadway median, and is accessed by weaving across the GPLs(general purpose lanes) before entering from the left lane of the GPLs. To maximize the potential for successful EBL operations, a critical design issue that requires special attention is the length of bus weaving section before entering EBL. The process of developing guidelines for the length of bus weaving section can be supported by a sensitivity analysis of performance measure (safety) with respect to the bus weaving distance. However, field data are difficult to obtain due to inherent complexity in creating performance measure (safety) samples under various interesting flows and bus weaving distance that are keys to research success. In this paper, VISSIM simulation is applied to simulate the operation of roadway weaving areas with EBL, and based on vehicle trajectory data from microscopic traffic simulation models, the Surrogate Safety Assessment Model (SSAM) computes the number of surrogate conflicts (or degree of safety) with respect to the bus weaving distance. Then, a multiple linear regression (MLR) model using safety data (number of surrogate conflicts) is developed. Finally, guidelines for bus weaving distance are established based on the developed MLR. Developed guidelines explicitly indicate that a longer bus weaving distance is required to maintain desired safety as weaving volume increases.

Removal of Organic Matter, Nitrogen and Phosphorus in an UASB Sewage Treatment Process with Recycle of Aerated Bio-Filter Effluent (UASB를 이용한 혐기성 하수처리공정에서 ABF 유출수 반송에 따른 유기물질과 질소 및 인 제거)

  • Tian, Dong-Jie;Byun, Byeong-Su;Lim, Hyun-Suk;Jun, Hang-Bae
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.35 no.5
    • /
    • pp.381-387
    • /
    • 2013
  • Nitrogen and phosphorus removal was investigated in an UASB-ABF (Up-flow anaerobic sludge blanket - aerated bio-filter) anaerobic sewage treatment system. Successful removal of nitrogen and phosphorus with organic matters was possible in the UASB-ABF system from the results of 160 days operation with the influent raw domestic sewage. Removal efficiencies of organic matter (as TCOD) showed 64% in UASB without recycle of the ABF effluent, however, they increased to 92%, 95%, 96% with 120%, 180% and 240% recycle of the ABF effluent, respectively. Increasement of the organic matter removal was not prominent at recycle ratio above 180%. Apparent increase in TN removal occurred with recycle of the ABF effluent. TN removal efficiency was 18% without recycle, but it increased to 82% with 240% recycle of the ABF effluent. And stable nitrification above 95% was possible as a result of efficient removal of organic matter in the UASB with and without recycle of the effluent. Removal of both TP and $PO{_4}^{3-}$-P also increased remarkably with recycle of the effluent. Without recycle of the effluent, that is at strict anaerobic condition in UASB, TP was not removed, however, its removal efficiency increased to 51%, 63%, 71% at recycle ratios of 120%, 180%, 240%, respectively mainly at UASB.

A Study on Brand Identity Revitalization for Aging Brand (노후화된 브랜드의 브랜드 아이덴티티 재활성화(Revitalization)를 위한 연구)

  • Koo, Yoo-Ri
    • Archives of design research
    • /
    • v.19 no.5 s.67
    • /
    • pp.335-350
    • /
    • 2006
  • Due to the development in industrial technology, changes in consumer behavior and aggravating competition within the industry, it is growing only harder every day to build up a strong brand power. Besides, a brand is supposed to age as time goes by, following a brand life cycle, as it is not a solid, immutable asset but something of a living creature. Therefore, self-renovation and revitalization efforts are needed, in order to incessantly confirm the self existence through the relationship with the consumer. In sum, revitalization operation is needed to renew a brand that has grown trite in the passage of time or due to the change in market condition, so as to bring it back anew to the consumers. This study did not stop at measuring the effect of a design renewal as a short-term assignment, but focused on the long-term brand management following the brand life cycle and aimed to define the effective timing and method of revitalization by comprehending the analysis results of consumer consciousness by analyzing the successful cases of brand revitalization and selecting the research analysis targets. As a result, this study proved that a properly-timed brand revitalization efforts in order to cope in advance with predictable changes in environment, can significantly prevent any drop of brand equity from occurring and then extend the brand life cycle. Also, this study could find that a brand revitalization is not a mere concept of a strategy for a short-term sales increase, but should be a long-term strategy to manage a brand, which must be practiced continuously in the time when the brand life cycle curve starts to fall. This research could also confirm that a superficial design renewal, which changes only the packaging of a brand, peformed in short-term haste, is not of help at all.

  • PDF

A Case of Orthognathic Surgery in Congenital Alveolar-Palatal cleft patient (구순 및 구개열을 가진 상악 후퇴증 환자의 교정-외과적 치험 1례)

  • Park, Jae-Hyun;Lee, Myung-Jin;Lee, Chang-Kon;Kim, Jong-Sub;Chin, Byung-Rho;Lee, Hee-Kyung
    • Journal of Yeungnam Medical Science
    • /
    • v.9 no.1
    • /
    • pp.189-196
    • /
    • 1992
  • Pre-surgical and post-surgical change in adult cleft lip and palate patient following Le Fort I advancement osteotomy combined with bone graft was evaluated clinically and cephalometically. We obtained a successful function and esthetic improvement. The bone graft of alveolo-palatal clefts provides a stable bone support to the adjacent teeth of the cleft area, and well union of adjacent bone tissue, the closure of oronasal fistula and improvement of speech problem. Le Fort I osteotomy following the ostectomy of nasal septum for advancement of the maxilla was obtained relative improvement of esthetics and functional occlusion. 1. The orthodontic correction was required before and after surgery. 2. In this case, there was a limited range of anterior advancement of the Premaxillary-segment due to the scar tissue. 3. After 8 months of operation, we could show the new bone deposition on the cleft site in dental radiograph and then the prosthetic treatement to the missing teeth was done.

  • PDF

The Relationship between MRO E-Commerce System and Purchase Effects

  • Kwon, Soon-Won;Kim, Young-Ei;Youn, Myoung-Kil;Jeon, Ta-Sik
    • Journal of Distribution Science
    • /
    • v.8 no.3
    • /
    • pp.5-15
    • /
    • 2010
  • Business corporations have become specialized and on the basis of various interests try to strengthen their competitiveness through a cooperative system of purchase, distribution, service and IT technology. And an advanced Internet-based electronic commerce has witnessed explosive growth and a business-to-business (B2B) electronic commerce. Through E-marketplace. business corporations achieve such diverse utilities as expenditure curtailment, process reduction and prime cost reduction. And with business depression worldwide and soaring prices of materials, many business corporations consider the introduction of comprehensive purchase of MRO (maintenance, repair and operation) materials. The Purpose of this study was to examine the definition of B2B E-marketplace and the utilities of MRO commerce correctly focusing on an empirical analysis of cases of MRO supply and purchase business corporations. The indications acquired from this research results are as follows. Firstly, as for MRO integrated purchase under the characteristics of the market environment, it had to use the supplier obligatorily through the integrated purchase on the level of CEO's decision-making or the group rather than the voluntary will of the purchasing department or the procurement department. Secondly, as for the present B2B E-marketplace MRO purchase, the purchasing agency business has formed the mainstream, but it is aiming at the diversification of the benefit by supplementing/correcting the business model such as category type, mediation business type, MRO-type advancing in the store inclusive of the purchasing agency business, keeping pace with the potential market of MRO. Thirdly, as for analysis of the products, the purchaser wants more various products and assortment of goods than those of the present time, and also to be provided with the precise product information. Especially, as the importance of the product sourcing becomes high, the whole energy has been bestowed on acquirement of the excellent suppliers. Fourth, as for use of B2B E-marketplace MRO integrated purchasing system, there are the purchasing companies complaining the inconvenience even until now, and there is the demerit spending the long time during the image move and the process treatment. It shall try to shorten the searching time and the process treatment time as the system is centered on the purchaser. In order to enhance the efficiency of MRO E-marketplace purchase, followings must be considered: First, because the importance of product sources ever increases, an excellent supplier must be secured earnestly. Second, the time of process must be reduced focusing on purchasers. B2B E-marketplace will increase and diversify electronic commerce continuously. Through MRO E-marketplace, business corporations will reduce expenditure, achieve a transparent and speedy trade, and purchase products of fine quality, thus establishing a most effective market. In addition, in this study the investigator brings focus into MRO which has not been clearly discussed in the academic and business world so far and intensively highlights an indirect material-oriented expenditure curtailment effect. By taking all the aspects of supplier, purchaser and practical economical value into account, the investigator presents a strategic direction for the successful comprehensive purchase of B2B MRO.

  • PDF