• 제목/요약/키워드: Production practice

검색결과 782건 처리시간 0.028초

UNS N08810 합금의 입계부식손상과 원인 분석 (Elucidation of Intergranular Corrosion of UNS N08810 alloys)

  • 김영식;황보덕
    • Corrosion Science and Technology
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    • 제11권5호
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    • pp.196-204
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    • 2012
  • Corrosion failure of petrochemical facilities is one of the difficulties in maintenance, since operating conditions of crude oil production, storage, and refinement are very aggressive. UNS N08810, which has been used for crude oil transportation pipes and storage tanks in petrochemical industries, shows good resistance to general corrosion and localized corrosion in several environments. Among its environments, UNS N08810 showed better corrosion resistance in fuel gas containing sulfuric acid and phosphoric acid and sulfur. However, ductility and toughness at high temperature over about $500^{\circ}C$ were greatly reduced due to microstructural change. In general, welding process is the representative method to join the parts in industrial components. Because the alloy by welding can be sensitized and corroded, the manufacturing process should be controlled. In this work, UNS N08810 was used and heat treatment conditions including solution and stabilization treatments were controlled. Oxalic acid etch test by ASTM A262 Practice A was done to evaluate the qualitative sensitization in room temperature. Huey test by ASTM A262 Practice C was done to evaluate the intergranular corrosion rate in boiling 65% $HNO_3$ solution. Also, the microstructure by thermal history was analyzed. Experimental alloy showed high intergranular corrosion rate and its corrosion mechanism was elucidated.

통제이론(統制理論)과 관리회계(管理會計) (Control Theory and Managerial Accouting)

  • 변용환
    • 산학경영연구
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    • 제1권
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    • pp.249-271
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    • 1987
  • Applicability of control theories to the efficient operation of accounting system is studied in this paper. Since managerial accounting has been developed along the progrees of control theory, management control theories are essential to explain important attributes of diverse accounting system. Basic concept of control is studied in depth and control systems are classified on the base of their special characteristics. And then the applicability of those control methods to accounting systems are discussed based on behavioral as well as management science approach. In the management science approach, accounting control models of production management, inventory management and R&D are designed with its unique quantitative characteristics. It, however, is very difficult to implement quantified control standards on the behavioral management side. Since most of variables considered on behavioral approach are non-quantitative, only discussion of the theoratical definition has been a main issue on previous studies. In this paper, practicability of the behavioral approach to the accounting control system is studied analyzing state variables and behavior variables of the control system. Theoratical base of the discussion are provided from control theories developed in organization theory and Economics. Basic objective of accounting control practice is to control qualitative human behavior represented by quantified figures while quantitative methods are prevailing over general accounting practice. Therefore, this paper tried to develope and integrate accounting control systems applicable to the behavioral management area as well as management science control side.

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An assessment of post-harvest fish losses and preservation practices in Siavonga district, Southern Zambia

  • Maulu, Sahya;Hasimuna, Oliver J.;Monde, Concilia;Mweemba, Malawo
    • Fisheries and Aquatic Sciences
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    • 제23권9호
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    • pp.25.1-25.9
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    • 2020
  • Fish is an extremely perishable food product which requires proper handling soon after harvest. The present study was aimed at assessing post-harvest fish losses and preservation practices in Siavonga district, Southern Zambia. Structured and semi-structured questionnaires were used to collect data on post-harvest fish losses and preservation practices from aquaculture producers, artisanal, and commercial fishers. All the fishers who landed on the lakeshore were interviewed, while aquaculture producers were randomly selected based on the information provided by the local department of fisheries. The results of the study revealed that all the fishers experienced post-harvest fish losses at varying degrees with those losing up to 10% of the total catch being in the majority. In contrast, aquaculture producers did not report any post-harvest fish losses. Most aquaculture producers commonly used chilling as preservation practice contrary to artisanal and commercial fishers who commonly used smoking and sun sun-drying respectively. Furthermore, fish product safety and quality control were poorly practiced in the district. Lack of cold storage facilities and fluctuating weather conditions were the major challenges impacting fish post-harvest activities. Therefore, to curb the loss of revenue due to post-harvest fish losses, we propose the introduction of new technology, self-development skills for fishing communities, and enhanced access to refrigeration facilities.

Effects of Task-Specific Obstacle Crossing Training on Functional Gait Capability in Patients with Cerebellar Ataxia: Feasibility Study

  • Park, Jin-Hoon
    • The Journal of Korean Physical Therapy
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    • 제27권2호
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    • pp.112-117
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    • 2015
  • Purpose: The purpose of this study was to examine the effects of a task-specific obstacle crossing rehabilitation program on functional gait ability in patients with cerebellar ataxia. Overall, we sought to provide ataxia-specific locomotor rehabilitation guidelines for use in clinical practice based on quantitative evidence using relevant analysis of gait kinematics including valid clinical tests. Methods: Patients with cerebellar disease (n=13) participated in obstacle crossing training focusing on maintenance of dynamic balance and posture, stable transferring of body weight, and production of coordinated limb movements for 8 weeks, 2 times per week, 90 minutes per session. Throughout the training of body weight transfer, the instructions emphasized conscious perception and control of the center of body stability, trunk and limb alignment, and stepping kinematics during the practice of each walking phase. Results: According to the results, compared with pre-training data, foot clearance, pre-&post-obstacle distance, delay time, and total obstacle crossing time were increased after intervention. In addition, body COM measures indicated that body sway and movement variability, therefore posture stability during obstacle crossing, showed improvement after training. Based on these results, body sway was reduced and stepping pattern became more consistent during obstacle crossing gait after participation in patients with cerebellar ataxia. Conclusion: Findings of this study suggest that task-relevant obstacle crossing training may have a beneficial effect on recovery of functional gait ability in patients with cerebellar disease.

KRR 1&2 제염$\cdot$해체에서 방사성 금속 고체폐기물의 관리 (Management of Metallic Radioactive Waste from Decontamination and Decommissioning of KRR 1&2)

  • 정기정;이동규;정경환;이근우;박진호
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2003년도 가을 학술논문집
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    • pp.645-649
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    • 2003
  • 제염 해체 설계단계에서 예견하였던 것과는 다르게 실제 제염$\cdot$해체 과정에서는 다양한 조건과 상황이 야기됨으로써, 실제 폐기물의 특성과 양이 당초 예상과는 다른 금속성 폐기물도 발생하게 된다. 이러한 금속성 폐기물을 관리하기 위한 관리시스템을 분석하고, 이에 대한 최적 처리방법 및 공정을 선정할 수 있는 단위기술을 고찰하였다. 또한 원자력시설 제염$\cdot$해체 동안 예견되는 상황에서 사용할 수 있는 적절한 기술과 공정관리시스템도 도출하였다.

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조선시대 양반가의 남녀 간 가내노동 분담: 보완적 역할 수행에 관한 연구 (The Complementary Gender Division of Household Work in the Yangban Class of the Choson Period)

  • 이기영;이현아;김성희
    • 가족자원경영과 정책
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    • 제11권4호
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    • pp.115-135
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    • 2007
  • The purpose of this study was to investigate the complementary gender division of housework in the Yangban ruling class of the Choson period. During the Choson period, genders were distinctly divided. It was generally regarded that women had to stay indoors and take care of household matters, while men, on the other hand, did not need to be concerned with housework because of the Confucian practice of "Naeoe". But homes in traditional society were considered as being at the center of production, so the study explores if women and men complemented each other through reviewed literature. As the results indicate, women and men in the Choson period complemented each other in some housework, even in the Yangban ruling class who maintained their authority by following the Confucian practice. From the findings, it can be concluded that the complementary relations between women and men in the Choson period should be emphasized as the origin of shared housework.

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Use of High Zinc Bath Entry Strip Temperature to Solve Coating Problems

  • Sippola, Pertti;Smith, David
    • Corrosion Science and Technology
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    • 제9권5호
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    • pp.175-186
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    • 2010
  • The auto industry is demanding more ductile high-strength steel grades to build lighter and stronger car bodies. The hot-dip galvanizing problems of these new steel grades are creating a demand for an improved method to control zinc wettability. The simplest way to improve zinc wettability on industrial hot-dip galvanizing lines is to increase the strip immersion temperature at zinc bath entry for enhancing the aluminothermic reaction. However, this practice increases the reactivity due to overheating the zinc in the snout which induces the formation of brittle Fe-Zn compounds at the strip/coating interface with the formation of higher amounts of dross in the zinc bath and snout contamination. Thus, this simple practice can only be utilized for short production periods of one to two hours without deteriorating coating quality. This problem has been solved by employing a technique that allows the use of a higher and attuned strip immersion temperature at zinc bath entry while still maintaining a constantly low zinc bath temperature. This has been proven to provide the solution for both the improved wettability and a significant reduction in the amounts of dross in the zinc bath.

Insect natural enemies as bioindicators in rice paddies

  • Ueno, Takatoshi
    • 농업과학연구
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    • 제39권4호
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    • pp.545-553
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    • 2012
  • In Asia, including Japan and Korea, rice paddies occupy the largest cultivated area in agricultural land. Rice paddies provide the habitats for many organisms including endemic species, sustaining high biodiversity. Insect natural enemies inhabiting rice paddies have an important function for rice production as agents of 'ecosystem services' because they play a major role in suppressing rice pests. The diversity and abundance of natural enemies can be a good index reflecting the 'healthiness' of agro-ecosystem services in rice paddies. The present study investigates whether insect natural enemies could be good biological indicators for general arthropod biodiversity and agricultural practice. First, the concept of ideal bio-indicators was summarized. The strategy to explore and select such bio-indicators was then proposed. Lastly, field survey was made to evaluate the abundance and biodiversity of natural enemies in Japanese rice paddies where chemical inputs, i.e., insecticide use, were different. The results showed that reduction of chemical inputs led to an increase in species richness or diversity of natural enemies including parasitoids and predators. Then, the data were analyzed to examine suitable indicator species to assess environmental soundness of agricultural practice and biodiversity in rice paddies. The density of several species of natural enemies did respond both to pesticide use and to general arthropod biodiversity. The analyses thus have indicated that natural enemies can be suitable as bio-indicators. Usefulness of indicator species in rice paddies is discussed in the context of ecologically sound agriculture.

병원약국의 소아약 조제업무 분석 (Analysis of Pediatric Drug Dispensing Practice at Hospital Pharmacies)

  • 정성아;이의경
    • 한국임상약학회지
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    • 제8권1호
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    • pp.47-53
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    • 1998
  • This study intended to investigate the pediatric drug dispensing practice at hospital pharmacies in order to provide the children with proper pharmaceutical care services. According to the study results, the most significant problem in dispensing pediatric drugs was that only a few pediatric drugs were supplied by the pharmaceutical companies in Korea. It was found that pediatric drugs like rifampicin, phenobarbital and theophylline should be produced in the form of syrup or powder, for the children to swallow drugs with ease. The study results also showed that only $35.5\%$ of the hospital pharmacists reviewed all the prescriptions issued by doctors. In most cases $(65.3\%)$ drug information was only provided when the patients asked to the pharmacists. The lack of working time and clinical information on the patients were found as major barriers. Thus in order to provide better pharmaceutical care services for the children, not only the pharmaceutical companies should pay attention to the production of pediatric drugs, but pharmacists should make every efforts on playing patient-oriented roles.

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Re-writing World Literature through Juxtaposition: Decolonizing Comparative Literature in Vietnam

  • Pham, Chi P.;Do, Ninh H.
    • 수완나부미
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    • 제14권1호
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    • pp.9-29
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    • 2022
  • Postcolonial critics have criticized Comparative Literature for exclusively studying literatures from the non-Western world through Western lenses. In other words, postcolonial criticism asserts that theorists and practitioners of comparative literature have traced the "assistance" of the classic "comparison and contrast" approach to an imperialist discourse, which sustains the superiority of Western cultures and economies. As a countermeasure to reading through the comparative lens, literary theories have offered a "juxtapositional model of comparison" that connects texts across cultures, places, and times. This paper examines practices of Comparative Literature in Vietnam, revealing how the engagement with decolonizing processes leads to a knowledge production that is paradoxically colonial. The paper also analyses implementations of this model in reading select Vietnamese works and highlights how conventional comparisons, largely based on historical influences and reception, maintain the colonial mapping of World Literature, centralizing Western, and more particularly, English Literature and in the process marginalizing the others. Therefore, the practice of juxtaposing Vietnamese literary works with canonical works of the World Literature will provoke dialogues and raise awareness of hitherto marginalized works to an international readership. In this process, the paper considers the contemporary interest of Comparative Literature practice in trans- national, trans-regional, trans-historical, and trans-cultural perspectives.