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A Study on the Disputable Issues of the Standard Form of Korea Service Contract - Focusing on Liquidated Damage and Minimum Quantity Commitment - (한국 컨테이너 해상화물 표준장기운송계약서 쟁점에 관한 연구 - 손해배상예정액과 최소약정물량을 중심으로 -)

  • Jae-woong Yoon;Yun-seok Hur
    • Korea Trade Review
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    • v.48 no.2
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    • pp.217-243
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    • 2023
  • This study revealed practical implications by analyzing the clauses and disputable issues of the Korea Service Contract. Korea introduced Servcie Contract in the container part since Hanjin Shipping's bankrupcy and distributed the standard form(2019). After that, the standard form was revised during the supply chain crisis(2022). In the standard form, there are clause that require agreement due to conflicting interests of shipper and carrier. Therefore, the main clauses of the standard form were analyzed to derive the practical meaning to the both parties. In addition, in the process of introducing the standard form, the most disputable issues, liquidated damages and minimum quality commitment, were deeply analyzed to explain how shipper and carriers' benefit and loss differ as the clause changes. In conclusion, both parties must set LD at a very reasonable level so that they do not proceed separately with penalty. In addition, 'evenly' is a much more important than quantity for carrier in the establishment of MQC, so extra box option for shipper even during the peak season is needed to accommodate with service contract.

Ecological Risk Assessment of 4,4'-Methylenedianiline (4,4'-Methylenedianiline의 환경매체별 위해성평가)

  • Hyun Soo Kim;Daeyeop Lee;Kyung Sook Woo;Si-Eun Yoo;Inhye Lee;Kyunghee Ji;Jungkwan Seo;Hun-Je Jo
    • Journal of Environmental Health Sciences
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    • v.49 no.6
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    • pp.334-343
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    • 2023
  • Background: South Korea's Act on Registration and Evaluation, etc. of Chemicals (known as K-REACH) was established to protect public health and the environment from hazardous chemicals. 4,4'-Methylenedianiline (MDA), which is used as a major intermediate in industrial polymer production and as a vulcanizing agent in South Korea, is classified as a toxic substance under the K-REACH act. Although MDA poses potential ecological risks due to industrial emissions and hazards to aquatic ecosystems, no ecological risk assessment has been conducted. Objectives: The aim of this study is to assess the ecological risk of MDA by identifying the actual exposure status based on the K-REACH act. Methods: Various toxicity data were collected to establish predicted no effect concentrations (PNECs) for water, sediment, and soil. Using the SimpleBox Korea v2.0 model with domestic release statistical data and EU emission factors, predicted environmental concentrations (PECs) were derived for ten sites, each referring to an MDA-using company. Hazard quotient (HQ) was calculated by ratio of the PECs and PNECs to characterize the ecological risk posed by MDA. To validate the results of modeling-based assessment, concentration of MDA was measured using in-site freshwater samples (two to three samples per site). Results: PNECs for water, sediment, and soil were 0.000525 mg/L, 4.36 mg/kg dw, and 0.1 mg/kg dw, respectively. HQ for surface water and sediment at several company sites exceeded 1 due to modeling data showing markedly high PEC in each environmental compartment. However, in the results of validation using in-site surface water samples, MDA was not detected. Conclusions: Through an ecological risk assessment conducted in accordance with the K-REACH act, the risk level of MDA emitted into the environmental compartments in South Korea was found to be low.

Explainable Artificial Intelligence (XAI) Surrogate Models for Chemical Process Design and Analysis (화학 공정 설계 및 분석을 위한 설명 가능한 인공지능 대안 모델)

  • Yuna Ko;Jonggeol Na
    • Korean Chemical Engineering Research
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    • v.61 no.4
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    • pp.542-549
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    • 2023
  • Since the growing interest in surrogate modeling, there has been continuous research aimed at simulating nonlinear chemical processes using data-driven machine learning. However, the opaque nature of machine learning models, which limits their interpretability, poses a challenge for their practical application in industry. Therefore, this study aims to analyze chemical processes using Explainable Artificial Intelligence (XAI), a concept that improves interpretability while ensuring model accuracy. While conventional sensitivity analysis of chemical processes has been limited to calculating and ranking the sensitivity indices of variables, we propose a methodology that utilizes XAI to not only perform global and local sensitivity analysis, but also examine the interactions among variables to gain physical insights from the data. For the ammonia synthesis process, which is the target process of the case study, we set the temperature of the preheater leading to the first reactor and the split ratio of the cold shot to the three reactors as process variables. By integrating Matlab and Aspen Plus, we obtained data on ammonia production and the maximum temperatures of the three reactors while systematically varying the process variables. We then trained tree-based models and performed sensitivity analysis using the SHAP technique, one of the XAI methods, on the most accurate model. The global sensitivity analysis showed that the preheater temperature had the greatest effect, and the local sensitivity analysis provided insights for defining the ranges of process variables to improve productivity and prevent overheating. By constructing alternative models for chemical processes and using XAI for sensitivity analysis, this work contributes to providing both quantitative and qualitative feedback for process optimization.

A Study on the Fatigue Strength of the Welded Joints in Steel Structures(II) (강구조물(鋼構造物)의 용접연결부(鎔接連結部)의 피로강도(疲勞强度)에 관한 연구(研究)(II))

  • Park, Je Seon;Chung, Yeong Wha;Chang, Dong Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.6 no.1
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    • pp.1-11
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    • 1986
  • Welded connectors of the cover plates, the transverse stiffeners of the plate girders, and the gusset plates of the plates girders or box girders, were selected as studying objects. A simplified method of drawing the S-N curves in these welded joints by a computer program without the direct fatigue tests was established. The plots on the S-N curve using the values from the practical fatigue tests were compared with the results from the method of the computer programming. The results of these studies are as follows. It appeared that the fatigue life by calculation method was a little less than the practical fatigue life from the actual tests. The latter values included both life $N_c$ of occurrence of initial crack $a_i$ and the life $N_p$ of propagation of critical crack. On the other hand, the former values included only the life $N_p$. Therefore, these results should be considered as justifiable ones. Since the difference between the two results was not significant, the results by calculation method should be in the conservation side when the safety of the structures was considered. Consequently, the results by calculation method should be applicable to the fracture fatigue design of structure. For reference, the same fatigue tests were performed with the specimens of 3 pieces in each case made of the low-strength steel, SS 41. The results went unexpected showing that the fatigue strength was lower in the case of low-strength steel. That is, in the case of the cover plate, the fatigue strength became slowly higher than the case of high-strength steel, SWS 50. That was observed when the maximum testing stress was higher than $14kg/mm^2$. In addition, in the case of the transverse stiffener, the fatique strength became rapidly higher than the case of SWS 50. That was observed when the maximum testing stress was lower than $31kg/mm^2$. It was thought that more such fatigue tests should be performed for more reliable results.

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Effects of Lipopolysaccride-induced Stressor on the Expression of Stress-related Genes in Two Breeds of Chickens (Lipopolysaccride 감염처리가 닭의 품종간 스트레스연관 유전자 발현에 미치는 영향)

  • Jang, In Surk;Sohn, Sea Hwan;Moon, Yang Soo
    • Korean Journal of Poultry Science
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    • v.44 no.1
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    • pp.1-9
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    • 2017
  • The objective of the present study was to determine the expression of genes associated with lipopolysaccharide (LPS)-induced stressor in two breeds of chickens: the Korean native chicken (KNC) and the White Leghorn chicken (WLH). Forty chickens per breed, aged 40 weeks, were randomly allotted to the control (CON, administered the saline vehicle) and LPS-injected stress groups. Samples were collected at 0 and 48 h post-LPS injection, and total RNA was extracted from the chicken livers for RNA microarray and quantitative real-time polymerase chain reaction (qRT-PCR) analyses. In response to LPS, 1,044 and 1,193 genes were upregulated, and 1,000 and 1,072 genes were downregulated in the KNC and WLH, respectively, using a ${\geq}2$-fold cutoff change. A functional network analysis revealed that stress-related genes were downregulated in both KNC and WLH after LPS infection. The results obtained from the qRT-PCR analysis of mRNA expression of heat shock 90 (HSP90), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), activating transcription factor 4 (ATF4), sterol regulatory element-binding protein 1 (SREBP1), and X-box binding protein 1 (XBP1) were confirmed by the results of the microarray analysis. There was a significant difference in the expression of stress-associated genes between the control and LPS-injected KNC and WLH groups. The qRT-PCR analysis revealed that the stress-related $HSP90{\alpha}$ and HMGCR genes were downregulated in both LPS-injected KNC and WLH groups. However, the HSP70 and $HSP90{\beta}$ genes were upregulated only in the LPS-injected KNC group. The results suggest that the mRNA expression of stress-related genes is differentially affected by LPS stimulation, and some of the responses varied with the chicken breed. A better understanding of the LPS-induced infective stressors in chicken using the qRT-PCR and RNA microarray analyses may contribute to improving animal welfare and husbandry practices.

Early Identification of Gifted Young Children and Dynamic assessment (유아 영재의 판별과 역동적 평가)

  • 장영숙
    • Journal of Gifted/Talented Education
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    • v.11 no.3
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    • pp.131-153
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    • 2001
  • The importance of identifying gifted children during early childhood is becoming recognized. Nonetheless, most researchers preferred to study the primary and secondary levels where children are already and more clearly demonstrating what talents they have, and where more reliable predictions of gifted may be made. Comparatively lisle work has been done in this area. When we identify giftedness during early childhood, we have to consider the potential of the young children rather than on actual achievement. Giftedness during early childhood is still developing and less stable than that of older children and this prevents us from making firm and accurate predictions based on children's actual achievement. Dynamic assessment, based on Vygotsky's concept of the zone of proximal development(ZPD), suggests a new idea in the way the gifted young children are identified. In light of dynamic assessment, for identifying the potential giftedness of young children. we need to involve measuring both unassisted and assisted performance. Dynamic assessment usually consists of a test-intervene-retest format that focuses attention on the improvement in child performance when an adult provides mediated assistance on how to master the testing task. The advantages of the dynamic assessment are as follows: First, the dynamic assessment approach can provide a useful means for assessing young gifted child who have not demonstrated high ability on traditional identification method. Second, the dynamic assessment approach can assess the learning process of young children. Third, the dynamic assessment can lead an individualized education by the early identification of young gifted children. Fourth, the dynamic assessment can be a more accurate predictor of potential by linking diagnosis and instruction. Thus, it can make us provide an educational treatment effectively for young gifted children.

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Field Study For The Improvement of Medication System and Method for Inpatients at General Hospital (입원환자의 투약체계와 방법의 개선을 위한 현장연구)

  • Yoo, Hyung-Sook;Kuwan, Young-Mi;Song, Mi-Sook;Kim, Hyung-Ae;Park, Kyung-Sook
    • Journal of Korean Academy of Nursing Administration
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    • v.1 no.1
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    • pp.147-211
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    • 1995
  • Medication is a kind of medical service and a therapeutic nursing function which takes large portion of nursing service and requires complicated procedures. So many different medical personnel should be involved and cooporate each other in order to accomplish medication. Medication is also a vital nursing service, So nurse feels heavy responsibi lity in that she gives medication to the patient finally, so she has much responsibility if medication error is happened. Therefore it seems very important to clarify the problem of medication system and method, and find the subculture of medication situation because it may promote nursing productivity. The study was conducted to 1. Describe and interpret medication situation. 2. Find out the problem of medication system and method and on alternatives. 3. Compare the medication system and method of hospitals which are located in Seoul with object hospital Ethnographic methodology was used to study medication situation by doing participant observation and interview of health care personnel. Ten nurses and three nurse aids were interviewed. Two residents and internists, two phamacists and two accountants were also interviewed. Data was obtained and analized according to Developmental Research Sequence introduced by Spradly. On the basis of this data the results were as follows. 1. The overall flow of medication system was devided into six stage : first, checking doctor's order : second writing doctor's order, : third, transfering slip into the related departments such as account department, pharmacy : fourth, distribution of medication from pharmacy to unit : fifth, identifing medication by nurses : and finally, medicating to the patient. Behaviorors have been under a lot of stress in that they have to do much works, especially paperworks, So too much time were needed. They also have been suffered interpersonal conflicts among health care personnel and role conflicts in the process of doing medication service. 2. In the process of checking order, the problem was that too much time was required for checking order and paperwork. The more the order changes the more the paperwork is. Nurses have been suffering difficulties in calling internist in order to get bill. Even if writing down slip for medication order is doctor's job, Sometimes nurse has been expected to write slip by doctors or nurse would write slip beacuse of two much complexities and efforts for calling doctors. If the slip were incorrect, much time complicated procedures were more required for correcting it. So delay of administering drug would be resulted consequently. Drugs were delivered from pharmacy to units by delivery agent and phamacist. But because drugs were delivered without arranging room number of patient. Nurse should rearrange drugs in order of the room number So it had made waste time and effort, and Even when emergency drugs were needed, Prompt delivery of drug was not easy because of many reasons. For nurses, it took too long in the identification of the right drug. Actually nurses have heavy burden when medication error happens because nurse is the final actor who gives medication to the patient, So every three shift nurse ought to check drugs as soon as every shift begins. That's why it took too much time due to repeated confirming procedure. When nurses had to go patient room in order to give medications, there were difficulties in watching patient until the patient take medicine correctly. So it was impossible to check every patient wheather he took medicine or not especially in hectic situation. 3. There were many hospitals in Seoul which have similar medication system and method as object hospital according to the results of questionaire. This means that many hospitals have been suffering srimilar problems which were identified in object hospital. 4. Recommendations for promoting simplification of medication system and method were the following : Redesigning of slip from two pieces of paper into one : early discharge announcement system, and slip confirming through computer and controlling of period of prescreption from one day to two or three days : designing personal drug storage box for each patient and using it. If nurses follow the recommendations, they will make medication short & simple, and also have enough time of direct nursing care 5. Even though there were many difficulties in medicating patients. Medication itself has been considered as a caring among nurses because it makes rapport between nurse and patient. So nurses had better accept medication as a portion of nusing service not a original portion of phamacist. There are some limits in this research in terms of confining to only one unit of one hospital, and treating it especially in view of nurses' aspects, So further researchs should be continnued from various kmds of viewpoints of doctors, phamacists and so on. ${\cdot\cdot\cdot}$. Especially esthnographic study of computerized medication system and method seems to be followed.

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Perfluoropolymer Membranes of Tetrafluoroethylene and 2,2,4Trifluofo- 5Trifluorometoxy- 1,3Dioxole.

  • Arcella, V.;Colaianna, P.;Brinati, G.;Gordano, A.;Clarizia, G.;Tocci, E.;Drioli, E.
    • Proceedings of the Membrane Society of Korea Conference
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    • 1999.07a
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    • pp.39-42
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    • 1999
  • Perfluoropolymers represent the ultimate resistance to hostile chemical environments and high service temperature, attributed to the presence of fluorine in the polymer backbone, i.e. to the high bond energy of C-F and C-C bonds of fluorocarbons. Copolymers of Tetrafluoroethylene (TEE) and 2, 2, 4Trifluoro-5Trifluorometoxy- 1, 3Dioxole (TTD), commercially known as HYFLON AD, are amorphous perfluoropolymers with glass transition temperature (Tg)higher than room temperature, showing a thermal decomposition temperature exceeding 40$0^{\circ}C$. These polymer systems are highly soluble in fluorinated solvents, with low solution viscosities. This property allows the preparation of self-supported and composite membranes with desired membrane thickness. Symmetric and asymmetric perfluoropolymer membranes, made with HYFLON AD, have been prepared and evaluated. Porous and not porous symmetric membranes have been obtained by solvent evaporation with various processing conditions. Asymmetric membranes have been prepared by th wet phase inversion method. Measure of contact angle to distilled water have been carried out. Figure 1 compares experimental results with those of other commercial membranes. Contact angles of about 120$^{\circ}$for our amorphous perfluoropolymer membranes demonstrate that they posses a high hydrophobic character. Measure of contact angles to hexandecane have been also carried out to evaluate the organophobic character. Rsults are reported in Figure 2. The observed strong organophobicity leads to excellent fouling resistance and inertness. Porous membranes with pore size between 30 and 80 nanometers have shown no permeation to water at pressures as high as 10 bars. However high permeation to gases, such as O2, N2 and CO2, and no selectivities were observed. Considering the porous structure of the membrane, this behavior was expected. In consideration of the above properties, possible useful uses in th field of gas- liquid separations are envisaged for these membranes. A particularly promising application is in the field of membrane contactors, equipments in which membranes are used to improve mass transfer coefficients in respect to traditional extraction and absorption processes. Gas permeation properties have been evaluated for asymmetric membranes and composite symmetric ones. Experimental permselectivity values, obtained at different pressure differences, to various single gases are reported in Tab. 1, 2 and 3. Experimental data have been compared with literature data obtained with membranes made with different amorphous perfluoropolymer systems, such as copolymers of Perfluoro2, 2dimethyl dioxole (PDD) and Tetrafluorethylene, commercialized by the Du Pont Company with the trade name of Teflon AF. An interesting linear relationship between permeability and the glass transition temperature of the polymer constituting the membrane has been observed. Results are descussed in terms of polymer chain structure, which affects the presence of voids at molecular scale and their size distribution. Molecular Dyanmics studies are in progress in order to support the understanding of these results. A modified Theodoru- Suter method provided by the Amorphous Cell module of InsightII/Discover was used to determine the chain packing. A completely amorphous polymer box of about 3.5 nm was considered. Last but not least the use of amorphous perfluoropolymer membranes appears to be ideal when separation processes have to be performed in hostile environments, i.e. high temperatures and aggressive non-aqueous media, such as chemicals and solvents. In these cases Hyflon AD membranes can exploit the outstanding resistance of perfluoropolymers.

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Mediating Effect of Opportunity Recognition Among Entrepreneurial Alertness, Mentoring, & Number of Mentoring on New Ventures' Performance (기업가적 기민성과 멘토링 및 멘토링 횟수와 기업성과 관계에서 기회인지의 매개효과 영향)

  • Park, Mi-Jung;Lee, Seon-Ho;Hwangbo, Yun
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.4
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    • pp.1-24
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    • 2021
  • The Korean government is currently expanding the business startup incubator support program and funds for new ventures with innovative technology in order to spread the second venture boom. However, despite the fact that entrepreneurial education and mentoring that entrepreneurs should have are important parts for the sustainable growth of the startup, some companies selected for government support programs are reluctant to participate in programs such as entrepreneurship education and mentoring for the sole purpose of funding commercialization. This research addressed the effects of entrepreneurial alertness with opportunity awareness as its medium and the small business mentoring service along with the number of times the mentoring has taken place, on the corporate performances. The results of empirical research are as follow: the first one is that scanning-search and evaluation-judgment can influence a company's performance (financial, non-financial) through opportunity recognition, with the exception of association-connection, which is a sub-factor of entrepreneurial alertness. Secondly, it was found to affect a company's financial and non-financial performance through opportunity recognition for financing mentoring, technical support mentoring, and management support mentoring. Thirdly, it was found that the number of mentoring also affects the financial and non-financial performance of a company through opportunity recognition. The implications of this study are that it should be revisited that program managers consider rooms that do not violate the startup founder's strategic decision-making opportunities when designing and operating the program as entrepreneurial alertness sub-factor association-connection does not affect corporate performance through opportunity recognition. This study also emphasizes the need for customized mentoring to meet the outcome goals of each startup, as it has been empirically clarified that the mentoring provided to the startup by the government's support is important. The contribution of this research is that entrepreneurial alertness and opportunity recognition that are treated as important components in research for entrepreneurship, and the factors of mentoring and mentoring frequency that are recognized as important elements in the practical aspect of startup business are clarified theoretically and empirically as an influential factor in corporate performance. And this study also provide a rationale for the startup business support agency supplying mentoring.

Rationalization Processes in the Entertainment Business on the Modern Theatrical Field - Concerning the Financiers and the Agents from 1907 to the early 1920s - (한국 초기 문화산업사에서 흥행의 합리화 과정에 대한 연구-1907~1920년대 초까지 흥행 주체를 중심으로-)

  • Kwon, Do-hee
    • (The) Research of the performance art and culture
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    • no.35
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    • pp.9-59
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    • 2017
  • This article describes the entertainment business system from 1907 to the first half of the 1920's. The entertainment business began at the time of Empire of Korea with the Imperial Theater called Hyeomnyulsa, which was supported by the emperor's authority and national system and run by the imperial court, especially Gungnaebu. However, after closing the imperial theater, many commercial theaters have been born since 1907, the role of the subject who dominate the entertainment business has been subdivided into financialist and agent. The financialist was replaced by civilians and the capacity of the agent has been strengthened after the introduction of Yeongeukgaeryanglon. In this condition the entertainment business had to be rationalized. In addition, before and after 1912, as the businessmen took part in the entertainment business instead of the government officials and social leaders, the role of entertainment business developed and became equipped with a modern system. Financialist who utilized economic capital was subdivided into the proprietor of a theater, investors, and bosses in the process of mobilizing the necessary funds for the construction, renovation, and repair of the theater, and agents who used cultural capital to practice and maintain performances, on the other hand played a role in expanding the diversity of the show in and outside the theater. In the theatre there was Chongmoo, Johapjang, Chwiche, and Jwadang of Gisaengjohaps, Sinpageukdans, Gyeongseonggupabaeujohap and various XXX Ilhaeng were outside the theater. They participated in the their own way. The financialist and agent used to set up cooperative relations and conflicts. The entertainment business was deepened and developed in the process of resolving the conflicts. However, Performance market could not grow as well as the possibility of a system equipped after 1915. This is because the Japanese imperialists limited the growth of the economic capital and cultural capital of the Koreans and even the composition of social capital. For this reason, Chosun's entertainment business system has grown in proportion to the absolute growth of the box office industry, but it has not developed as much as its potential capacity.